Implantable Cardioverter Defibrillator
|Original Policy Date
|Last Review Status/Date
Reviewed with literature search/10:2014
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Our medical policies are designed for informational purposes only and are not an authorization, or an explanation of benefits, or a contract. Receipt of benefits is subject to satisfaction of all terms and conditions of the coverage. Medical technology is constantly changing, and we reserve the right to review and update our policies periodically.
Indications for ICD implantation can be broadly subdivided into (1) secondary prevention, ie, their use in patients who have experienced a potentially life-threatening episode of VT (near sudden cardiac death); and (2) primary prevention, ie, their use in patients who are considered at high risk for sudden cardiac death but who have not yet experienced life-threatening VT or ventricular fibrillation (VF).
The standard ICD involves placement of a generator in the subcutaneous tissue of the chest wall. Transvenous leads are attached to the generator and threaded intravenously into the endocardium. The leads sense and transmit information on cardiac rhythm to the generator, which analyzes the rhythm information and produces an electrical shock when a malignant arrhythmia is recognized.
A totally subcutaneous ICD (S-ICD®) has also been developed. This device does not employ transvenous leads and thus avoids the need for venous access and complications associated with the venous leads. Rather, the S-ICD® uses a subcutaneous electrode that is implanted adjacent to the left sternum. The electrodes sense the cardiac rhythm and deliver countershocks through the subcutaneous tissue of the chest wall.
Several automatic ICDs are approved by the U.S. Food and Drug Administration (FDA) through the premarket application approval process. FDA-labeled indications generally include patients who have experienced life-threatening VT associated with cardiac arrest or VT associated with hemodynamic compromise and resistance to pharmacologic treatment. Devices manufactured by Guidant are approved by FDA for use “in patients at high risk of sudden cardiac death due to ventricular arrhythmias and who have experienced at least 1 of the following: an episode of cardiac arrest (manifested by the loss of consciousness) due to a ventricular tachyarrhythmia; recurrent, poorly tolerated sustained ventricular tachycardia (VT); or a prior myocardial infarction (MI) , left ventricular ejection fraction of less than or equal to 35%, and a documented episode of nonsustained VT, with an inducible ventricular tachyarrhythmia.” On July 18, 2002, FDA expanded the approved indications for the Guidant ICD devices to include the prophylactic use of Guidant ICDs for cardiac patients who have had a previous heart attack and have an ejection fraction that is 30% or less. This expanded indication is based on the results of the second Multicenter Automatic Defibrillator Implantation Trial (MADIT II trial), which is discussed here. Medtronic devices are approved “to provide ventricular antitachycardia pacing and ventricular defibrillation for automated treatment of life-threatening ventricular arrhythmias.” Other devices have approval language similar to that of Medtronic.
FDA has approved a large number of ICDs through the PMA process (FDA product code: LWS). A 2014 review of FDA approvals of cardiac implantable devices reported that between 1979 and 2012, FDA approved 19 ICDs (7 pulse generators, 3 leads, 9 combined systems) through new PMA applications.(1) Many originally-approved ICDs have undergone multiple supplemental applications. A summary of some
currently-available ICDs is provided in Table 1 (not an exhaustive list).
Table 1. Implantable Cardioverter Defibrillator With FDA Approval
Ellipse/Fortify Assura Family (originally: Cadence Tiered Therapy Defibrillation System)
St. Jude Medical Inc. (St. Paul, MN)
Current Plus ICD (originally: Cadence Tiered Therapy Defibrillation System)
St. Jude Medical Inc. (St. Paul, MN)
Dynagen, Inogen, Origen, and Teligen Family (originally: Ventak, Vitality, Cofient family)
Boston Scientific Inc. (Marlborough, MA)
Evera Family (originally: Virtuosos/Entrust/Maximo/ Intrisic/ Marquis family)
Medtronic Inc. (Minneapolis, MN)
Subcutaneous Implantable Defibrillator System
Cameron Health Inc. (San Clemente, CA); acquired by Boston Scientific Inc.
FDA: Food and Drug Administration; PMA: premarket application.
NOTE: ICDs may be combined with other pacing devices, such as pacemakers for atrial fibrillation, or biventricular pacemakers designed to treat heart failure. This policy addresses ICDs alone, when used solely to treat patients at risk for ventricular arrhythmias.
The use of the automatic implantable cardioverter defibrillator (ICD) may be considered medically necessary in adults who meet the following criteria:
- ischemic cardiomyopathy with New York Heart Association (NYHA) functional class II or class III symptoms, a history of myocardial infarction at least 40 days before ICD treatment, and left ventricular ejection fraction of 35% or less; or
- ischemic cardiomyopathy with NYHA functional class I symptoms, a history of myocardial infarction at least 40 days before ICD treatment, and left ventricular ejection fraction of 30% or less; or
- nonischemic dilated cardiomyopathy and left ventricular ejection fraction of 35% or less, after reversible causes have been excluded, and the response to optimal medical therapy has been adequately determined; or
- hypertrophic cardiomyopathy (HCM) with 1 or more major risk factors for sudden cardiac death (history of premature HCM-related sudden death in 1 or more first-degree relatives younger than 50 years; left ventricular hypertrophy greater than 30 mm; 1 or more runs of nonsustained ventricular tachycardia at heart rates of 120 beats per minute or greater on 24-hour Holter monitoring; prior unexplained syncope inconsistent with neurocardiogenic origin) and judged to be at high risk for sudden cardiac death by a physician experienced in the care of patients with HCM.
- Patients with a history of a life-threatening clinical event associated with ventricular arrhythmic events such as sustained ventricular tachyarrhythmia, after reversible causes (eg, acute ischemia) have been excluded.
The use of the ICD is considered investigational in primary prevention patients who:
- have had an acute myocardial infarction (ie, less than 40 days before ICD treatment);
- have NYHA class IV congestive heart failure (unless patient is eligible to receive a combination cardiac resynchronization therapy ICD device);
- have had a cardiac revascularization procedure in past 3 months (coronary artery bypass graft [CABG] or percutaneous transluminal coronary angioplasty [PTCA]) or are candidates for a cardiac revascularization procedure; or
- have noncardiac disease that would be associated with life expectancy less than 1 year.
The use of the ICD may be considered medically necessary in children who meet any of the following criteria:
- survivors of cardiac arrest, after reversible causes have been excluded;
- symptomatic, sustained ventricular tachycardia in association with congenital heart disease in patients who have undergone hemodynamic and electrophysiologic evaluation; or
- congenital heart disease with recurrent syncope of undetermined origin in the presence of either ventricular dysfunction or inducible ventricular arrhythmias.
The use of the ICD is considered investigational for all other indications in pediatric patients.
The use of a subcutaneous ICD is considered investigational for all indications in adult and pediatric patients.
This policy addressed the use of ICD devices as stand-alone interventions, not as combination devices to treat heart failure (ie, cardiac resynchronization devices) or in combination with pacemakers. Unless specified, the policy statements and policy rationale are referring to transvenous ICDs.
Indications for pediatric ICD use are based on American College of Cardiology/American Heart Association/Heart Rhythm Society (ACC/AHA/HRS) guidelines published in 2008, which acknowledged the lack of primary research in this field on pediatric patients (see Rationale section). These are derived from nonrandomized studies, extrapolation from adult clinical trials, and expert consensus.
Effective in 2015, the CPT coding for these devices was updated to include insertion of subcutaneous ICD devices (see Code Table)
BlueCard/National Account Issues
State or federal mandates (e.g., FEP) may dictate that all devices approved by the U.S. Food and Drug Administration (FDA) may not be considered investigational, and thus these devices may be assessed only on the basis of their medical necessity.
Medicare has specified a “desire to ensure that defibrillator implantation only occurs in those patients who are most likely to benefit and that the procedures are done only by competent providers in facilities with a history of good outcomes and a quality assessment/improvement program to identify providers with poor outcomes and other areas for improvement.” Medicare noted it is “concerned that the available evidence does not allow providers to target these devices to patients who will clearly derive benefit.” Therefore, Medicare “will require that reimbursement for [implantable cardioverter defibrillator] ICDs for primary prevention of sudden cardiac death occur only if the beneficiary receiving the defibrillator implantation is enrolled in either an FDA-approved category B Investigational Device Exemption clinical trial or a qualifying national database (registry).” (See Rationale section.)
Because of the Medicare reimbursement policy, ICD placement may require out-of-network referral. Plans may decide whether or not to encourage non-Medicare member participation in qualifying registries.
This policy was created in 1996 and updated periodically with literature review. The most recent update with literature review covers the period through September 7, 2014.
Overview and Summary of TEC Assessments
Automatic implantable cardiac defibrillators (ICDs) were first used in survivors of near sudden cardiac death. There has been ongoing interest in using ICDs as primary preventive therapy in patients with risk factors for sudden cardiac death. The first ICD TEC Assessment, published in 2002, addressed this indication.(2) The Assessment focused on the Multicenter Automatic Defibrillator Implantation Trials (known as MADIT I and MADIT II) that compared the use of an ICD with conventional therapy among patients with coronary artery disease with a prior history of myocardial infarction (MI) and a current history of a reduced ejection fraction. The key difference in the 2 trials was the patient selection criteria. In the MADIT I trial, patients were required to have a left ventricular ejection fraction (LVEF) of less than 35% but also ventricular tachyarrhythmia (VT), as evidenced on an electrophysiologic study. In the subsequent, MADIT II, trial, patients were required to have a lower ejection fraction, less than 30%, but no electrophysiologic study was required. Therefore, the patient selection criteria of the MADIT II trial potentially identify a much larger number of candidates for ICD implantation.
The 2002 TEC Assessment concluded, “For patients who have coronary artery disease with prior MI and reduced LVEF and who are similar to those selected in MADIT I and MADIT II, the available evidence demonstrates an improvement in overall mortality associated with ICD treatment compared with conventional therapy.”
In October 2004, TEC reassessed ICDs.(3) The 2004 TEC Assessment focused on the results of the 5 randomized controlled trials (RCTs) included in the 2002 Assessment (including the Multicenter Unsustained Tachycardia Trial [MUSTT], MADIT I, MADIT II, Coronary Artery Bypass Graft [CABG] Patch Trial, and the Cardiomyopathy Trial [CAT]) and 5 additional RCTs:
- Defibrillator in Acute Myocardial Infarction Trial (DINAMIT);
- Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT)
- Comparison of Medical Therapy, Pacing, and Defibrillation in Heart Failure (COMPANION);
- Defibrillators in Non-Ischemic Cardiomyopathy Treatment Evaluation (DEFINITE); and
- Amiodarone versus Implantable Defibrillator Randomized Trial (AMIOVIRT).
The 2004 TEC Assessment made the following conclusions about the use of ICD devices.
The use of ICD devices meets the TEC criteria in the prevention of sudden death from VT in patients who have:
- Symptomatic (defined as the presence of dyspnea on exertion, angina, palpitations, or fatigue) ischemic dilated cardiomyopathy with a history of MI at least 40 days before ICD treatment and LVEF of 35% or less; or
- Symptomatic (defined as the presence of dyspnea on exertion, angina, palpitations, or fatigue) nonischemic dilated cardiomyopathy for more than 9 months’ duration and LVEF of 35% or less.
The use of ICD devices does not meet the TEC criteria in the prevention of sudden death from ventricular tachyarrhythmia in patients who
- have had an acute MI (ie, less than 40 days before ICD treatment);
- have New York Heart Association (NYHA) class IV congestive heart failure (unless patient is eligible to receive a combination cardiac resynchronization therapy ICD device);
- have had cardiac revascularization procedure in past 3 months ( CABG or percutaneous transluminal coronary angioplasty [PTCA]) or are candidates for a cardiac revascularization procedure; or
- have noncardiac disease that would be associated with life expectancy less than 1 year.
Further analysis of existing trial data using patient-level meta-analysis may further delineate which subgroups of patients are likely to benefit from ICD placement and those unlikely to benefit who can be spared the morbidity of ICD placement.
The 2004 TEC Assessment based its conclusions on the following indication-specific evidence.
Patients Who Have Prior MI and Reduced LVEF
The 2002 Assessment concluded that the evidence was sufficient to demonstrate that ICD therapy improves net health outcome in patients with prior MI and reduced LVEF. Both new studies (SCD-HeFT, COMPANION) and the reanalysis of MUSTT findings provide additional supportive evidence of improved outcomes in patients with prior MI. The hazard ratio (HR) for all-cause mortality in the ischemic subgroup of SCD-HeFT was 0.79 (95% confidence interval [CI], 0.60 to 1.04), which is close to that observed in MADIT II (HR=0.69; 95% CI, 0.51 to 0.93), and these findings provide additional supportive evidence that ICD therapy reduces mortality. There may be slight but not statistically significantly increased rates of adverse effects (AEs) associated with ICD therapy; however, serious device-related events are not common. On balance, the significant reductions in mortality associated with ICD therapy outweigh the harms associated with ICD therapy in comparison with conventional treatment. Thus, the available evidence again demonstrates that ICD therapy improves health outcomes in patients with coronary artery disease and prior MI and reduced LVEF.
Patients Who Have Acute MI and Reduced LVEF
The evidence reviewed in the 2004 TEC Assessment was insufficient to permit conclusions regarding the effect of ICD therapy on net health outcome for this indication.
Patients Who Have No Prior MI and Reduced LVEF (eg, Nonischemic Dilated Cardiomyopathy)
Results from subjects with nonischemic dilated cardiomyopathy (NIDCM) included in SCD-HeFT and DEFINITE suggest a mortality benefit from ICD therapy, although statistical significance that was not achieved in these studies was likely related to insufficient power. A meta-analysis(4) of 5 trials including nonischemic subjects reports a statistically significant reduction in mortality associated with ICD therapy. Furthermore, when the body of evidence for ICD therapy in both ischemic and nonischemic populations is considered together, the preponderance of evidence suggests that ICD therapy improves health outcomes compared with medical management alone with a relative risk reduction in all-cause mortality between 21% and 35%. While the risk of AEs is not well-reported in studies of patients without prior MI, it seems reasonable to expect similar low rates of device-related AEs as seen in studies of patients with prior MI.
Device-related AEs were inconsistently reported in the available trials, although serious AEs appear to be uncommon. What is known about device-related AEs does not outweigh the significant mortality benefits demonstrated in various studies.
Subsequent Evidence and Guidelines for the Use of ICDs in Adults
Relevant evidence and most current guidelines identified through Medline published following the 2004 TEC Assessment through October 2014 relates to the following subjects:
- Identification of predictors of better/worse outcomes after ICD placement.
- Use of ICD after acute MI: Reports of BEST-ICD (Beta-blocker Strategy + ICD), and IRIS trials
- Use of ICD in nonischemic dilated cardiomyopathy, with focus on implantation timing
- Use of ICD in hypertrophic cardiomyopathy
The BEST-ICD (Beta-blocker Strategy + ICD) trial randomized 143 patients 5 to 30 days after acute MI to evaluate whether electrophysiology studies were useful to guide ICD placement and improve outcomes in patients at high risk of sudden death.(5) Entry criteria included an LVEF of 35% or less along with 1 or more noninvasive risk factors (eg, premature ventricular contractions, heart rate variability, signal-averaged
electrocardiography [SAECG]-positive) and be given maximal tolerated β-blockers (metoprolol) therapy. The authors concluded that using electrophysiology studies to guide ICD placement within 5 to 30 days after MI did not significantly improve outcomes and survival. This is consistent with the conclusions that ICD placement after early MI does not improve outcomes. The authors also noted that the study screened
more than 15,000 patients but ended after randomizing only 12% of the targeted study population, largely because there were far fewer patients with LVEF less than 35% than expected based on experience reported in the literature.
The Immediate Risk Stratification Improves Survival (IRIS) trial evaluated ICD implantation early after MI.(6) Eligible patients were required to have an LVEF 40% or less and either: (1) a heart rate 90 or more beats per minute on initial electrocardiogram or (2) nonsustained VT during Holter monitoring, or both. From 92 centers and 62,944 patients post-MI, 898 were randomized 5 to 31 days following the MI to ICD implantation or medical therapy. Seventy-seven percent had experienced ST elevation MI, 72% of whom underwent PTCA. During a mean 37-month follow-up, overall mortality was similar in the 2 arms (ICD vs medical therapy, HR=1.04; 95% CI, 0.81 to 1.35). However, the risk of sudden cardiac death was lower following ICD (HR=0.52; 95% CI, 0.35 to 0.78), but nonsudden cardiac death risk was greater (HR=1.8;
95% CI, 1.0 to 3.2). These results are consistent with guidelines and previous trials.
High-Risk Hypertrophic Cardiomyopathy
Maron et al7 reported appropriate ICD discharge rates (terminating either VT or fibrillation [VF]) from an international registry of high-risk hypertrophic cardiomyopathy (HCM) patients enrolled at 42 referral and nonreferral institutions. Between 1986 and 2003, ICDs were implanted in 506 patients with HCM—383 for primary prevention and 123 for secondary prevention. The mean age of patients was 42 years (SD=17),
and 28% were 30 years of age or younger; 36% were female; mean follow-up was 3.7 years (SD=2.8). Criteria considered in the study placing patients at high risk and, therefore, candidates for primary prevention included: (1) history of premature HCM-related sudden death in 1 or more first-degree relatives younger than 50 years of age; (2) left ventricular hypertrophy greater than 30 mm; (3) 1 or more runs of nonsustained VT at heart rates of 120 beats per minute or greater on 24-hour Holter monitoring; and (4) prior unexplained syncope inconsistent with neurocardiogenic origin. Abnormal exercise blood pressure was not reported. In the primary prevention group, appropriate discharges occurred at an annual rate of 3.6% (95% CI, 2.7% to 4.8%), in the secondary prevention group 10.6% (95% CI, 7.9% to 13.9%);
respective 5-year cumulative probabilities of first appropriate discharge were 17% and 39%. If each appropriate discharge was life-saving, 5-year numbers needed to benefit (NNTBs) could be as low as 5.9 and 2.6 for primary and secondary prevention, respectively, when considering only the first appropriate discharge.
However, when analyzed in NIDCM, Ellenbogen et al(8) concluded that approximately one-half of arrhythmias terminated by appropriate ICD discharges are not life-threatening. The NNTBs calculated, therefore, represent lower bounds or greatest potential benefit, and the true benefit is likely less (only 6.3% of primary prevention patients had >1 appropriate discharge). AE rates included 1 or more inappropriate discharges (27%); infections (3.8%); hemorrhage or thrombosis (1.6%); lead fractures, dislodgement, and oversensing (6.7%). While the number of risk factors present was not associated with cumulative probability to first appropriate discharge for primary prevention, patient selection for ICD implantation was performed by experienced clinicians. These results, obtained outside the setting of a clinical trial, apply under such conditions.
Al-Khatib and Curtis(9) published an analysis of whether ICD implantations in the U.S. followed evidencebased guidelines using a Medicare ICD registry. There were a total of 111,707 patients who received an ICD between January 2006 and June 2009. Of these, 25,145 (22.5%) did not meet the evidence-based criteria according to ACC/AHA/HRS guidelines.(10) Patients who did not meet evidence-based ICD criteria had a higher mortality than patients who did meet criteria (0.57% vs 0.18%, respectively; p<0.001) and also had a higher rate of procedural complications (3.2% vs 2.4%, respectively; p<0.001). Electrophysiologists had a lower rate of nonevidence-based ICD use compared with
nonelectrophysiologists (20.8% vs 24.8%, respectively; p<0.001).
Nonischemic Dilated Cardiomyopathy
For patients with nonischemic cardiomyopathy (NICM), the optimal timing of ICD implantation remains uncertain. A substantial percent of patients diagnosed with NICM will improve following initial diagnosis, even when a reversible cause of NICM cannot be identified. Given the current available evidence, it is not possible to predict which patients with idiopathic NICM will improve, nor is it possible to accurately estimate the time course for improvement. The specification of a 9-month waiting period before ICD implantation arises from the selection criteria of the CAT trial,(11) which restricted enrollment to patients with onset of NICM within 9 months. While the results of this trial did not show a benefit for patients with recent onset of NICM, the trial was stopped early due to an unexpectedly low rate of events and was thus underpowered to detect a difference in mortality between groups.
Kadish and Subacius(11) performed a post hoc analysis of the DEFINITE trial data to examine whether the time from diagnosis of NIDCM was associated with the magnitude of benefit from ICD implantation. Survival benefit was found only for those diagnosed less than 9 months before implantation (n=216); no benefit was apparent when NIDCM was diagnosed more than 9 months before (n=242). However, there was a significant discrepancy between arms in the time from diagnosis to randomization—standard therapy patients were randomized a median of 20 months after diagnosis, while those in the ICD arm had a median of 8 months. The trial was neither designed nor powered to examine a time effect, and the analyses conflict with findings of the smaller (n=104) Cardiomyopathy (CAT) trial(12) reviewed in the 2002 TEC Assessment. Further evidence is necessary to define when in the natural history of the disease ICD implantation is appropriate.
The Definite trial enrolled NICM patients without regard to time since onset, and a post hoc analysis revealed that the benefit was found mainly in patients with onset of NICM for less than 9 months. Neither of these pieces of evidence represents strong data to support a specific time interval before implanting an ICD in patients with NICM.
Zecchin et al(13) performed a cohort study on 503 consecutive patients diagnosed with idiopathic NICM to determine the extent to which indications for an ICD evolved over the several months following an initial NICM diagnosis. At initial diagnosis, 245 met SCD-HeFT criteria for an ICD, based on an ejection fraction less than 35% and class II-III heart failure, and 258 did not meet criteria for an ICD. At a mean follow-up of 5.4 months, during which patients were treated with angiotensin-converting enzyme inhibitors and β-blockers, there were consistent improvements in ejection fraction and symptoms, such that less than one third of evaluable patients (31%) still had indications for ICD. Of patients who initially did not have an indication for an ICD, a total of 10% developed indications for an ICD at follow-up. This study highlights the fact that a decision for ICD implantation should not be made before optimal treatment and stabilization of patients with newly diagnosed NICM, because the indications for ICD are not stable over time and will change in a substantial numbers of patients following treatment.
A prospective registry sponsored by the National Heart, Lung, and Blood Institute enrolled 373 patients with recent-onset NICM, and compared mortality in patients receiving an early ICD with those receiving the device at a later time.(14) Forty-three patients received an ICD within 1 month of diagnosis, with a 1-year survival for this group of 97%. Three hundred thirty patients received an ICD between 1 and 6 months, with a 1-year survival of 98%. Seventy-three patients received an ICD at a time period longer than 6 months, with a 1-year survival. Survival at 2 and 3 years was also similar between groups, with no significant differences.
Some experts consider patients with recently diagnosed NICM and either sustained VT or unexplained syncope to be candidates for earlier ICD implantation due to their higher risk of lethal arrhythmias. However, evidence on this specific population is lacking, and the natural history of patients in this category is not well-characterized. The most recent ACC/AHA guidelines(10,15) do not specifically address the optimal waiting period before implantation of an ICD for patients with newly diagnosed NICM.
Perrson et al published a systematic review and meta-analysis of AEs following ICD implantation.(16) The authors included data from 35 cohort studies, reported in 53 articles. In-hospital serious AE rates ranged from 1.2% to 1.4%, most frequently pneumothorax (0.4%-0.5%) and cardiac arrest (0.3%). Posthospitalization complication rates were variable: device-related complications occurred in 0.1% to 6.4%; lead-related complications in 0.1% to 3.9%; infection in 0.2% to 3.7%; thrombosis in 0.2% to 2.9%; and inappropriate shock in 3% to 21%.
The failure of ICD leads in several specific ICD devices has lead the U.S. Food and Drug Administration (FDA) to require St. Jude Medical to conduct 3-year postmarket surveillance studies to address concerns related to premature insulation failure and to address important questions related to follow-up of affected patients.(17)
Ricci et al(18) evaluated the incidence of lead failure in a cohort study of 414 patients implanted with an ICD with Sprint-Fidelis leads. Patients were followed for a median of 35 months. Lead failures occurred in 9.7% (40/414) of patients, for an annual rate of 3.2% per patient-year. Most of the lead failures (87.5%) were due to lead fracture. The median time until recognition of lead failure, or until an AE, was 2.2 days.
A total of 22 patients (5.3%) received an inappropriate shock due to lead failure.
Cheng et al(19) examined the rate of lead dislodgements in patients enrolled in a national cardiovascular registry. Of 226,764 patients treated with an ICD between April 2006 and September 2008, lead dislodgement occurred in 2628 (1.2%). Factors associated with lead dislodgement were NYHA class IV heart failure, AF/flutter, a combined ICD-CRT device, and having the procedure performed by a nonelectrophysiologist. Lead dislodgement was associated with an increased risk for other cardiac adverse events and death.
Several publications have reported on infection rates in patients receiving an ICD. Smit and Schonheyder(20) published a retrospective, descriptive analysis of the types and distribution of infections associated with ICDs over a 10-year period in Denmark. Of 91 total infections identified, 39 (42.8%) were localized pocket infections, 26 (28.6%) were endocarditis, 17 (18.7%) were ICD-associated bacteremic infections, and 9 (9.9%) were acute postsurgical infections. Nery and Nair(21) reported the rate of ICD-associated infections among consecutive patients treated with an ICD at a tertiary referral center. There were a total of 24 infections among 2417 patients for a rate of 1.0%. Twenty-two of 24 patients with infections (91.7%) required device replacement. Factors associated with infection were device replacement (vs de novo implantation) and use of a complex device (eg, combined ICD-CRT or dual/triple chamber devices). Sohail et al22 performed a case-control study evaluating the risk factors for infection in 68 patients with an ICD infection and 136 matched controls. On multivariate analysis, the presence of epicardial leads (odds ratio [OR], 9.7; p=0.03) and postoperative complications at the insertion site (OR=27.2, p<0.001) were significant risk factors for early infection. For late-onset infections, prolonged hospitalization for more than 3 days (OR=33.1, p<0.001 for 2 days vs 1 day) and chronic obstructive pulmonary disease (OR=9.8, p=0.02) were significant risk factors.
Tan et al conducted a systematic review to identify outcomes and AEs associated with ICDs that have built-in therapy reduction programming.(23) Six randomized trials and 2 nonrandomized cohort studies were included, including 7687 patients (3598 with conventional ICDs and 4089 therapy reduction programming). A total of 267 patients received inappropriate ICD shocks (4.9%); 99 (3.4%) in the therapy reduction and 168 (6.9%) in the conventional programming group (relative risk [RR], 50%; 95% CI, 37% to 61%; p<0.001). Therapy reduction programming was associated with a significantly lower risk of death compared with conventional programming (RR=30%; 95% CI, 16% to 41%; p<0.001.)
Lee et al(24) evaluated the rate of early complications among patients enrolled in a prospective, multicenter population-based registry of all newly implanted ICDs in Ontario, Canada from February 2007 through May 2009. Of 3340 patients receiving an ICD, major complications (lead dislodgement requiring intervention, myocardial perforation, tamponade, pneumothorax, infection, skin erosion, hematoma requiring intervention) within 45 days of implantation occurred in 4.1% of new implants. Major complications were more common in women, in patients who received a combined ICD-CRT (cardiac resynchronization therapy) device, and in patients with a left ventricular end-systolic size of larger than 45 mm. Direct implant-related complications were associated with a major increase in early death (HR=24.9, p<0.01).
Use of Automatic ICDs in the Pediatric Population
There is limited direct scientific evidence on the efficacy of ICDs in the pediatric population. Most published studies in this area are retrospective analyses of small case series. A review of some of the representative publications of this type is summarized next.
The largest published series was a combined series of pediatric patients and patients with congenital heart disease from 4 clinical centers.(25) The median age of this population was 16 years, although some adults were included up to the age of 54 years. A total of 443 patients were included. The most common diagnoses were tetralogy of Fallot and HCM. ICD implantation was performed for primary prevention in 52% of patients and for secondary prevention in 48%. Over a 2-year period of follow-up, appropriate shocks occurred in 26% of patients and inappropriate shocks occurred in 21%.
Silka et al(26) compiled a database of 125 pediatric patients treated with an ICD, through query of the manufacturers of commercially available devices. Indications for ICD placement were survivors of cardiac arrest in 95 patients (76%), drug-refractory VT in 13 patients (10%), and syncope with heart disease plus inducible VT in 13 patients (10%). During a mean follow-up of 31 +/- 23 months, 73 patients (59%)
received at least 1 appropriate shock and 25 patients (20%) received at least 1 inappropriate shock. The actuarial rates of sudden-death-free survival were 97% at 1 year, 95% at 2 years, and 90% at 5 years.
Alexander et al(27) reported on 90 ICD procedures in 76 young patients with a mean age of 16 years (range, 1-30). Indications for placement were 27 patients (36%) with cardiac arrest or sustained VT, 40 patients (53%) with syncope, 17 patients (22%) with palpitations, 40 patients (53%) with spontaneous ventricular arrhythmias, and 36 patients (47%) with inducible VT. Numerous patients had more than 1 indication for ICD in this study. Over a median of 2-year follow-up, 28% of patients received an appropriate shock, and 25% of patients received an inappropriate shock. Lewandowski et al(28) reported on long-term follow-up of 63 patients between the ages of 6 to 21 years who were treated with an ICD device. After a 10-year follow-up, there were 13 (21%) patients with surgical infections. Fourteen patients (22%) experienced at least 1 appropriate shock and 17 patients (27%) had at least 1 inappropriate shock. Serious psychological sequelae developed in 27 patients (43%).
The subcutaneous ICD is intended for patients who do have standard indications for an ICD, but who do not require pacing for bradycardia, or antitachycardia overdrive pacing for VT. There were no RCTs identified that compared the performance of a subcutaneous ICD (S-ICD) with transvenous ICDs. Two nonrandomized, comparative studies were identified that compared the efficacy of the 2 different types of ICDs, and numerous single-arm studies report on outcomes of the S-ICD.
Nonrandomized Comparative Studies
Kobe et al compared the efficacy of the S-ICD and the transvenous ICD in terminating laboratory-induced VF.(29) Sixty-nine patients from 3 centers in Germany treated with an S-ICD were matched for age and gender with 69 patients treated with a transvenous ICD. One patient in the transvenous ICD group developed a pericardial effusion requiring pericardiocentesis. Termination of induced VF was successful in 89.5% of the patients in the S-ICD group, compared with 90.8% of patients with a transvenous ICD (p=0.815). Patients in both groups were followed for a mean of 217 days. One patient in the S-ICD group had the device explanted at 8 weeks due to local infection, and a second patient had the S-ICD changed to a transvenous ICD because of the need for antitachycardia overdrive pacing due to frequent episodes of VT. There were 3 patients in the S-ICD group who received appropriate shocks for ventricular arrhythmias compared with 9 patients in the transvenous group (p=0.05). Inappropriate shocks occurred in 5 patients in the S-ICD group and 3 patients in the transvenous ICD group (p=0.75).
The Subcutaneous versus Transvenous Arrhythmia Recognition Testing (START) study compared the performance of a subcutaneous ICD with a transvenous ICD for detecting arrhythmias in the electrophysiology lab.(30) The patient population included 64 patients who were scheduled for ICD implantation. All patients had a transvenous ICD placed, as well as subcutaneous electrodes attached to an S-ICD. Arrhythmias were induced and the sensitivity and specificity of detection by each device was compared. For ventricular arrhythmias, sensitivity of detection was 100% for the S-ICD and 99% for the transvenous ICD. Specificity was 98.0% for the S-ICD device compared with 76.7% for the transvenous device (p<0.001).
A number of single-arm studies have been published that report on outcomes of patients treated with an S-ICD. The largest such study was reported by Lambiase et al who described patients in the EFFORTLESS-ICD registry, a multicenter European registry to report outcomes for patients treated with S-ICD.(31) At the time of analysis, the registry included 472 patients, 241 of whom (51%) were enrolled prospectively, at a median follow-up time of 498 days. Nine patients (2%) died during the reported period, none of the deaths which were known to occur in the perioperative period, although the cause of death was unknown for 1 patient. A total of 317 spontaneous episodes in 85 patients were recorded during the follow-up, of which 169 episodes received therapy in 59 patients. Of the 145 classified untreated episodes, 93 were adjudicated as inappropriate sensing, 37 were nonsustained VT/VF, 12 were nonsustained SVT above discrimination zone, and 3 were unclassified. Of the VT/VF episodes, the first shock conversion efficacy was 88%, with 100% overall successful clinical conversion after a maximum of 5 shocks. A total of 73 inappropriate shocks were recorded in 32 patients over an average follow-up of 18 months (360 day inappropriate shock rate of 7%).
A second large series was a multicenter study 330 patients from several countries, the S-ICD System Clinical Investigation (S-ICD IDE Study).(32) The S-ICD was successfully implanted in 314 of 330 patients (95.1%). Laboratory-induced VF was successfully terminated in more than 90% of patients, which was one of the primary outcomes of the study. The second primary outcome, greater than 99% freedom from complications at 180 days, was also met. Patients were followed for a mean duration of 11 months. There were 38 spontaneous episodes of VT in 21 patients (6.7%), and all were successfully terminated. Inappropriate shocks were received by 41 patients (13.1%).
Gold et al published a subanalysis of patients in the S-ICD IDE study to evaluate a discrimination algorithm to reduce inappropriate shocks.(33) Patients in the study could receive 1 of 2 shock detection algorithms, a single- or double-zone configuration. In the single-zone configuration, shocks are delivered for detected heart rates above the programmed rate threshold. In the dual-zone configuration, arrhythmia
discrimination algorithms are active in a lower rate zone up to a shockable heart rate threshold. At hospital discharge, dual-zone programming was used in 226 subjects (72%) and single-zone programming was used in the remaining 88 subjects (28%). Inappropriate shocks occurred on 23 of 226 (10.2%) subjects with dual-zone programming and 23 of 88 (26.1%; p<0.001) subjects with single-zone programming. Freedom from appropriate shocks did not differ between groups.
Bardy et al described the development and testing of the device, including empiric evidence for the optimal placement of the subcutaneous electrode, in 2010.(34) A total of 55 patients were tested in the electrophysiology lab for termination of induced arrhythmias and subsequently followed for a mean of 10.1 months for successful termination of detected arrhythmias and clinical outcomes. In the electrophysiology lab study, intraoperative VF was induced in 53 of 55. All episodes were correctly detected by the S-ICD. In 52 of 53 patients, 2 consecutive episodes of ventricular arrhythmia were successfully terminated. In the final patient, the arrhythmia was terminated on 1 occasion but not on the other. In the cohort portion of this study, 54 of 55 patients were alive at last follow-up. The 1 death was due to renal failure, and this patient requested removal of the S-ICD before death. An infection at the generator site occurred in 2 patients, necessitating a revision procedure. Another 3 patients had lead dislodgement requiring repositioning. There were a total of 12 episodes of VT that were detected by the S-ICD; all 12 episodes were successfully terminated by countershock.
A series of 118 patients from 4 centers in the Netherlands was published in 2013.(35) Patients were followed for a mean of 18±7 months. Device-related complications occurred in 14% of patients, including infection (5.9%), dislodgement of the device or leads (3.3%), skin erosion (1.7%), and battery failure (1.7%). In 1 patient, the S-ICD was replaced with a transvenous ICD because of the need for antitachycardia pacing. Over the entire follow-up period, 8 patients experienced 45 appropriate shocks, with a first-shock conversion efficacy of 98%. Fifteen patients (13%) received a total of 33 inappropriate shocks. Two patients died, 1 due to cancer and 1 to progressive heart failure.
S-ICD Safety: Inappropriate Shocks
Although Kobe et al reported no differences between inappropriate shock rates in patients treated transvenous ICD or S-ICD, noncomparative studies have reported relatively high rates of inappropriate shocks with S-ICD. Inappropriate shocks from S-ICDs often result from T-wave oversensing. Because the sensing algorithm and the discrimination algorithm for arrhythmia detection is fixed in the S-ICD, management to reduce inappropriate shocks for an S-ICD differs from that for a transvenous ICD. Kooiman et al reported inappropriate shock rates among 69 patients treated at a single center with an S- ICD between February 2009 and July 2012 who were not enrolled in 1 of 2 other concurrent trials.(35) Over a total follow-up of 1316 months (median per patient, 21 months), the annual incidence of inappropriate shocks was 10.8%. In 8 patients, inappropriate shocks were related to T wave oversensing. After patients underwent adjustment of the sensing vector, no further inappropriate shocks occurred in 87.5% of patients with T wave oversensing.
Groh et al evaluated an electrocardiographic (ECG) screening test to determine patients who are potential S-ICD candidates who are at risk for T wave oversensing.(36) One hundred patients who had previously undergone transvenous ICD implantation and who were not receiving bradycardia pacing and did not have an indication for pacing were included. ECGs were obtained with lead placement to mimic the sensing vectors available on the S-ICD, and a patient was considered to qualify for S-ICD if the screening ECG template passed in any same lead supine and standing, at any gain, and without significant morphologic changes in QRS complexes. Of the included subjects who were potentially eligible for S-ICD, 8% were considered to fail based the ECG screening. The authors conclude that “More work is needed in S-ICD sensing algorithms to increase patient eligibility for the S-ICD.”
Ongoing and Unpublished Clinical Trials
An online search of ClinicalTrials.gov in September 2015 found several ongoing randomized trials of ICD therapy:
- A PRospective, rAndomizEd Comparison of subcuTaneOous and tRansvenous ImplANtable Cardioverter Defibrillator Therapy (PRAETORIAN) (NCT01296022): PRAETORIAN is a randomized, open-label trial to compare S-ICD placement with transvenous ICD placement in patients with a class I or IIa indication for ICD therapy. The primary outcome is the number of patients with ICD-related AEs. Enrollment is planned for 850 subjects; the estimated study completion date is June 2018.
- Efficacy of Implantable Defibrillator Therapy After a Myocardial Infarction (REFINE-ICD) (NCT00673842): REFINE-ICD is a randomized, open-label trial to compare prophylactic ICD placement with usual care in patients with a history of MI and better-preserved LV function. The primary outcome is mortality. Enrollment is planned for 1400 subjects; the estimated study completion date is December 2019.
- Efficacy and Safety of ICD Implantation in the Elderly (NCT02121158): This is a randomized, open-label trial to evaluate the safety and efficacy of ICD in preventing SCD in elderly patients with an indication for ICD for primary prevention. The primary outcome is all-cause mortality. Enrollment is planned for 85 subjects; the estimated study completion date is November 2015.
Clinical Input Received From Physician Specialty Societies and Academic Medical Centers
In response to requests, input was received from no physician specialty societies and 6 academic medical centers while this policy was under review in 2011. While the various physician specialty societies and academic medical centers may collaborate with and make recommendations during this process through the provision of appropriate reviewers, input received does not represent an endorsement or position statement by the physician specialty societies or academic medical centers, unless otherwise noted.
For most policy indications, including pediatric indications, there was agreement from those providing input. On the question of timing of ICD implantation, input was mixed, with some commenting about the potential role of early implantation in selected patients. Reviewers indicated that a waiting period of 9 months for patients with NICM was not supported by the available evidence or consistent with the prevailing practice patterns in academic medical centers. Specialty society input emphasized the difficulty of prescribing strict timeframes given the uncertainty of establishing the onset of cardiomyopathy and the inability to risk stratify patients based on time since onset of cardiomyopathy.
Summary of Evidence
There is an extensive literature base on the use of implantable cardioverter defibrillators (ICDs) in patients with prior arrhythmogenic events and ischemic cardiomyopathy. Earlier trials first demonstrated a benefit in overall mortality for survivors of cardiac arrest and patients with potentially lethal cardiac arrhythmias. Multiple, well-done, randomized controlled trials (RCTs) have also demonstrated a benefit in overall mortality for patients with ischemic cardiomyopathy and reduced ejection fraction. The indications for ICDs in these groups of patients parallel the inclusion criteria for the major trials and the recommendations from major specialty society guidelines. RCTs of early ICD implantation following acute myocardial infarction (MI) do not support a benefit for immediate ICD implantation versus delayed implantation for at least 40 days.
For nonischemic cardiomyopathy (NICM), there is less clinical trial evidence available, but the available evidence from a limited number of RCTs enrolling patients with NICM, and from subgroup analysis of RCTs with mixed populations, supports a survival benefit for this group. There is not high-quality evidence available to determine whether early versus delayed implantation improves outcomes for patients with NICM, and it is not possible to determine the optimal waiting period for ICD implantation following onset of NICM. At least 1 cohort study reports that most patients who meet criteria for an ICD at the time of initial NICM diagnosis will no longer meet the criteria for an ICD several months after initiation of treatment.
For pediatric patients, there is no direct evidence on the benefit of ICD implantation from high-quality clinical trials. Indications for pediatric patients are based on specialty society guidelines and from specialty society clinical input, both of which extrapolate findings from adult populations to the pediatric population.
A subcutaneous ICD (S-ICD®) has been developed that does not employ transvenous leads, with the goal of reducing lead-related complications. Evidence from nonrandomized controlled studies report success rates in terminating laboratory-induced ventricular fibrillation that are similar to transvenous ICD. However, there is scant evidence on comparative clinical outcomes of both types of ICD over longer periods of time. Case series report high rates of detection and successful conversion of ventricular tachycardia, and inappropriate shock rates that are in the range reported for transvenous ICD. This evidence is not sufficient to determine whether there are small differences in efficacy between the 2 types of devices, which may be clinically important due to the nature to the disorder being treated. Also, the adverse event rate is uncertain, with variable rates of adverse events reported in the available studies. At least 1 RCT is currently underway to compare the S-ICD with the transvenous ICD. Because of the uncertainties around whether the S-ICD is as effective as transvenous ICD and uncertainties around the adverse event rates, the use of the S-ICD is considered investigational.
Practice Guidelines and Position Statements
American College of Cardiology/American Heart Association Heart Failure Management Guidelines
In 2013, the American College of Cardiology (ACC) and American Heart Association (AHA) issued practice guidelines on the management of heart failure which made the following recommendations about the use of ICD devices as primary prevention(37):
- For patients with stage B heart failure, an ICD is reasonable in patients with asymptomatic ischemic cardiomyopathy who are at least 40 d post-MI, have an LVEF ≤30%, and on guidelinedirected medical therapy (GDMT). (class of recommendation: IIa; level of evidence: B).
- For patients with stage C heart failure:
- ICD therapy is recommended for primary prevention of sudden cardiac death (SCD) in selected patients with heart failure with reduced ejection fraction (HFrEF) at least 40 d postmyocardial infarction (MI) with left ventricular ejection fraction (LVEF) ≤35% and NYHA class II or III symptoms on chronic GDMT, who are expected to live at least 1 year. (Class of recommendation: I; level of evidence: A).
- ICD therapy is recommended for primary prevention of SCD in selected patients with HFrEF at least 40 d post-MI with LVEF ≤330% and NYHA class I symptoms while receiving GDMT, who are expected to live at least 1 year. (Class of recommendation: I; level of evidence: B).
- An ICD is of uncertain benefit to prolong meaningful survival in patients with a high risk of nonsudden death such as frequent hospitalizations, frailty, or severe comorbidities. (Class of recommendation: IIb; level of evidence: B).
ACC/AHA Device-Based Therapy for Cardiac Rhythm Abnormalities Guidelines
In 2012, ACC and AHA, together with the Heart Rhythm Society (HRS), the American Association of Thoracic Surgeons, and the Society of Thoracic Surgeons, issued a focused update to 2008 guidelines for device-based therapy of cardiac rhythm abnormalities.(38) The guidelines make the following recommendations related to ICD therapy in adults, all of which are based on the expectation that patients are receiving optimal medical therapy and have a reasonable expectation of survival with a good functional status for more than a year:
- Class I recommendations:
- ICD therapy is indicated in patients who are survivors of cardiac arrest due to ventricular fibrillation (VF) or hemodynamically unstable sustained ventricular tachycardia (VT) after evaluation to define the cause of the event and to exclude any completely reversible causes.
(Level of Evidence: A).
- ICD therapy is indicated in patients with structural heart disease and spontaneous sustained VT, whether hemodynamically stable or unstable. (Level of Evidence: B)
- ICD therapy is indicated in patients with syncope of undetermined origin with clinically relevant, hemodynamically significant sustained VT or VF induced at electrophysiological study. (Level of Evidence: B)
- ICD therapy is indicated in patients with LVEF less than or equal to 35% due to prior MI who are at least 40 days post-MI and are in NYHA functional Class II or III. (Level of Evidence: A)
- ICD therapy is indicated in patients with nonischemic dilated cardiomyopathy (DCM) who have an LVEF less than or equal to 35% and who are in NYHA functional Class II or III. (Level of Evidence: B)
- ICD therapy is indicated in patients with LV dysfunction due to prior MI who are at least 40 days post-MI, have an LVEF less than or equal to 30%, and are in NYHA functional Class I. (Level of Evidence: A)
- ICD therapy is indicated in patients with nonsustained VT due to prior MI, LVEF less than or equal to 40%, and inducible VF or sustained VT at electrophysiological study. (Level of Evidence: B)
- ICD therapy is indicated in patients who are survivors of cardiac arrest due to ventricular fibrillation (VF) or hemodynamically unstable sustained ventricular tachycardia (VT) after evaluation to define the cause of the event and to exclude any completely reversible causes.
- Class IIa recommendations:
- ICD implantation is reasonable for patients with unexplained syncope, significant LV dysfunction, and nonischemic DCM. (Level of Evidence: C)
- ICD implantation is reasonable for patients with sustained VT and normal or near-normal ventricular function. (Level of Evidence: C)
- ICD implantation is reasonable for patients with HCM who have 1 or more major† risk factors for sudden cardiac death (SCD). (Level of Evidence: C)
- ICD implantation is reasonable for the prevention of SCD in patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy who have 1 or more risk factors for SCD. (Level of Evidence: C)
- ICD implantation is reasonable to reduce SCD in patients with long-QT syndrome who are experiencing syncope and/or VT while receiving beta blockers. (Level of Evidence: B)
- ICD implantation is reasonable for nonhospitalized patients awaiting transplantation. (Level of Evidence: C)
- ICD implantation is reasonable for patients with Brugada syndrome who have had syncope. (Level of Evidence: C)
- ICD implantation is reasonable for patients with Brugada syndrome who have documented VT that has not resulted in cardiac arrest. (Level of Evidence: C)
- ICD implantation is reasonable for patients with catecholaminergic polymorphic VT who have syncope and/or documented sustained VT while receiving beta blockers. (Level of Evidence: C)
- ICD implantation is reasonable for patients with cardiac sarcoidosis, giant cell myocarditis, or Chagas disease. (Level of Evidence: C)
- Class IIb recommendations:
- ICD therapy may be considered in patients with nonischemic heart disease who have an LVEF of less than or equal to 35% and who are in NYHA functional Class I. (Level of Evidence: C)
- ICD therapy may be considered for patients with long-QT syndrome and risk factors for SCD. (Level of Evidence: B)
- ICD therapy may be considered in patients with syncope and advanced structural heart disease in whom thorough invasive and noninvasive investigations have failed to define a cause. (Level of Evidence: C)
- ICD therapy may be considered in patients with a familial cardiomyopathy associated with sudden death. (Level of Evidence: C)
- ICD therapy may be considered in patients with LV noncompaction. (Level of Evidence: C)
- Class III recommendations (not recommended):
- ICD therapy is not indicated for patients who do not have a reasonable expectation of survival with an acceptable functional status for at least 1 year, even if they meet ICD implantation criteria specified in the Class I, IIa, and IIb recommendations above. (Level of Evidence: C)
- ICD therapy is not indicated for patients with incessant VT or VF. (Level of Evidence: C)
- ICD therapy is not indicated in patients with significant psychiatric illnesses that may be aggravated by device implantation or that may preclude systematic follow-up. (Level of Evidence: C)
- ICD therapy is not indicated for NYHA Class IV patients with drug-refractory congestive heart failure who are not candidates for cardiac transplantation or cardiac resynchronization/defibrillator. (Level of Evidence: C)
- ICD therapy is not indicated for syncope of undetermined cause in a patient without inducible ventricular tachyarrhythmias and without structural heart disease. (Level of Evidence: C)
- ICD therapy is not indicated when VF or VT is amenable to surgical or catheter ablation (e.g., atrial arrhythmias associated with the Wolff-Parkinson-White syndrome, RV or LV outflow tract VT, idiopathic VT, or fascicular VT in the absence of structural heart disease). (Level of
- ICD therapy is not indicated for patients with ventricular tachyarrhythmias due to a completely reversible disorder in the absence of structural heart disease (e.g., electrolyte imbalance, drugs, or trauma). (Level of Evidence: B)
The 2012 guidelines make the following recommendations related to ICD therapy in children:
- Class I recommendations:
- ICD implantation is indicated in the survivor of cardiac arrest after evaluation to define the cause of the event and to exclude any reversible causes. (Level of Evidence: B)
- ICD implantation is indicated for patients with symptomatic sustained VT in association with congenital heart disease who have undergone hemodynamic and electrophysiological evaluation. Catheter ablation or surgical repair may offer possible alternatives in carefully selected patients. (Level of Evidence: C)
- Class IIa recommendations: ICD implantation is reasonable for patients with congenital heart disease with recurrent syncope of undetermined origin in the presence of either ventricular dysfunction or inducible ventricular arrhythmias at electrophysiological study. (Level of Evidence:
- Class IIb recommendations: ICD implantation may be considered for patients with recurrent syncope associated with complex congenital heart disease and advanced systemic ventricular dysfunction when thorough invasive and noninvasive investigations have failed to define a cause.
(Level of Evidence: C)
- Class III recommendations: All Class III recommendations found in Section 3, “Indications for Implantable Cardioverter-Defibrillator Therapy,” apply to pediatric patients and patients with congenital heart disease, and ICD implantation is not indicated in these patient populations. (Level of Evidence: C)
ACC/AHA Expert Consensus Statement on ICD Therapy in Patients Not Well Represented in Clinical Trials
In 2014, HRS, ACC, and AHA published an expert consensus statement on the use of ICD therapy in patients who were not included or poorly represented in ICD clinical trials, which made a number of consensus-based guidelines on the use of ICDs in selected patient populations.(39)
ACC/AHA Guidelines for Hypertrophic Cardiomyopathy
In 2011, ACCF/AHA guidelines were published on the management of patients with hypertrophic cardiomyopathy.(40) These guidelines contained the following statements about the use of ICD in patients with HCM:
Class I Recommendations
- The decision to place an ICD in patients with HCM should include application of individual clinical judgment, as well as a thorough discussion of the strength of evidence, benefits, and risks to allow the informed patient’s active participation in decision making. (Level of Evidence: C)
- ICD placement is recommended for patients with HCM with prior documented cardiac arrest, ventricular fibrillation, or hemodynamically significant VT. (Level of Evidence: B)
Class IIa Recommendations
- It is reasonable to recommend an ICD for patients with HCM with:
- Sudden death presumably caused by HCM in 1 or more first-degree relatives. (Level of Evidence: C)
- A maximum LV wall thickness greater than or equal to 30 mm. (Level of Evidence: C)
- One or more recent, unexplained syncopal episodes. (Level of Evidence: C)
- An ICD can be useful in select patients with NSVT [nonsustained VT] (particularly those <30 years of age) in the presence of other SCD risk factors or modifiers. (Level of Evidence: C)
- An ICD can be useful in select patients with HCM with an abnormal blood pressure response with exercise in the presence of other SCD risk factors or modifiers. (Level of Evidence: C)
It is reasonable to recommend an ICD for high-risk children with HCM, based on unexplained syncope, massive LV hypertrophy, or family history of SCD, after taking into account the relatively high complication rate of long-term ICD implantation. (Level of Evidence: C).
Class IIb Recommendations
- The usefulness of an ICD is uncertain in patients with HCM with isolated bursts of NSVT when in the absence of any other SCD risk factors or modifiers. (Level of Evidence: C)
- The usefulness of an ICD is uncertain in patients with HCM with an abnormal blood pressure response with exercise when in the absence of any other SCD risk factors or modifiers, particularly in the presence of significant outflow obstruction. (Level of Evidence: C)
Class III Recommendations: Harm
- ICD placement as a routine strategy in patients with HCM without an indication of increased risk is potentially harmful. (Level of Evidence: C)
- ICD placement as a strategy to permit patients with HCM to participate in competitive athletics is potentially harmful. (Level of Evidence: C)
- ICD placement in patients who have an identified HCM genotype in the absence of clinical manifestations of HCM is potentially harmful. (Level of Evidence: C)
U.S. Preventive Services Task Force Recommendations
Use of implantable cardioverter defibrillators is not a preventive service.
Medicare National Coverage
In January 2005, Medicare issued the following revised national coverage guideline for the use of ICDs.(41)
The Centers for Medicare and Medicaid Services (CMS) determined that the evidence is adequate to conclude that an ICD is reasonable and necessary for the following:
- Patients with ischemic dilated cardiomyopathy (IDCM), documented prior MI, NYHA class II and III heart failure, and measured LVEF of 35% or less;
- Patients with nonischemic dilated cardiomyopathy (NIDCM) >9 months, NYHA class II and III heart failure, and measured LVEF of 35% or less;
- Patients who meet all current CMS coverage requirements for a cardiac resynchronization therapy (CRT) device and have NYHA class IV heart failure;
For each of these groups, patients must not have:
- Cardiogenic shock or symptomatic hypotension while in a stable baseline rhythm;
- Had a coronary artery bypass graft (CABG) or PTCA within the past 3 months;
- Had an acute MI within the past 40 days;
- Clinical symptoms or findings that would make them a candidate for coronary revascularization;
- Irreversible brain damage from preexisting cerebral disease;
- Any disease, other than cardiac disease (eg, cancer, uremia, liver failure), associated with a likelihood of survival less than 1 year;
In addition, CMS specifies that the beneficiary receiving the ICD implantation for primary prevention must be enrolled in either an FDA-approved category B Investigational Device Exemption clinical trial (42 CFR §405.201), a trial under the CMS Clinical Trial Policy (NCD Manual §310.1), or a qualifying data collection system including approved clinical trials and registries.
The Medicare policy for ischemic and nonischemic dilated cardiomyopathy is consistent with this policy.
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- Gold MR, Theuns DA, Knight BP, et al. Head-to-head comparison of arrhythmia discrimination performance of subcutaneous and transvenous ICD arrhythmia detection algorithms: the START study. J Cardiovasc Electrophysiol. Apr 2012;23(4):359-366. PMID 22035049
- Lambiase PD, Barr C, Theuns DA, et al. Worldwide experience with a totally subcutaneous implantable defibrillator: early results from the EFFORTLESS S-ICD Registry. Eur Heart J. Jul 1 2014;35(25):1657-1665. PMID 24670710
- Weiss R, Knight BP, Gold MR, et al. Safety and Efficacy of a Totally Subcutaneous Implantable-Cardioverter Defibrillator. Circulation. Aug 27 2013;128(9):944-953. PMID 23979626
- Gold MR, Weiss R, Theuns DA, et al. Use of a discrimination algorithm to reduce inappropriate shocks with a subcutaneous implantable cardioverter-defibrillator. Heart Rhythm. Aug 2014;11(8):1352-1358. PMID 24732366
- Bardy GH, Smith WM, Hood MA, et al. An entirely subcutaneous implantable cardioverter-defibrillator. N Engl J Med. Jul 1 2010;363(1):36-44. PMID 20463331
- Kooiman KM, Knops RE, Olde Nordkamp L, et al. Inappropriate subcutaneous implantable cardioverterdefibrillator shocks due to T-wave oversensing can be prevented: Implications for management. Heart Rhythm. 2014;11(3):426-434. PMID
- Groh CA, Sharma S, Pelchovitz DJ, et al. Use of an electrocardiographic screening tool to determine candidacy for a subcutaneous implantable cardioverter-defibrillator. Heart Rhythm. Aug 2014;11(8):1361-1366. PMID 24755323
- Yancy CW, Jessup M, et al. 2013 ACCF/AHA Guideline for the Management of Heart Failure: A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. AHA Journal 2013(June 2013). PMID
- Tracy CM, Epstein AE, Darbar D, et al. 2012 ACCF/AHA/HRS Focused Update Incorporated Into the ACCF/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm AbnormalitiesA Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines and the Heart Rhythm Society. J Am Coll Cardiol. 2013;61(3):e6-e75. PMID
- Kusumoto FM, Calkins H, Boehmer J, et al. HRS/ACC/AHA Expert Consensus Statement on the Use of Implantable Cardioverter-Defibrillator Therapy in Patients Who Are Not Included or Not Well Represented in Clinical Trials. J Am Coll Cardiol. 2014;64(11):1143-1177. PMID
- Gersh BJ, Maron BJ, Bonow RO, et al. 2011 ACCF/AHA guideline for the diagnosis and treatment of hypertrophic cardiomyopathy: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. Dec 13 2011;124(24):e783-831. PMID 22068434
- Centers for Medicare and Medicaid Services. Medicare policy. http://www.cms.gov/Research-Statistics-Data-and-Systems/Files-for-Order/NonIdentifiableDataFiles/ICDImplantationData.html. Accessed August 2014.
|33216||Insertion of transvenous electrode; single chamber (one electrode) permanent pacemaker or single chamber pacing cardioverter-defibrillator|
|33217||dual chamber (two electrodes) permanent pacemaker or dual chamber pacing cardioverter-defibrillator|
|33218||Repair of single transvenous electrode, permanent pacemaker or pacing cardioverter-defibrillator|
|33220||Repair of 2 transvenous electrodes for permanent pacemaker or pacing cardioverter-defibrillator|
|33223||Revision of skin pocket for cardioverter-defibrillator|
|33230||Insertion of pacing cardioverter-defibrillator pulse generator only; with existing dual leads|
|33231||Insertion of pacing cardioverter-defibrillator pulse generator only; with existing multiple leads|
Insertion of single or dual chamber pacing cardioverter-defibrillator pulse generator
Subcutaneous removal of single or dual chamber pacing cardioverter-defibrillator pulse generator
Removal of single or dual chamber pacing cardioverter-defibrillator electrode(s); by thoracotomy
by transvenous extraction
Insertion of epicardial single or dual chamber pacing cardioverter-defibrillator electrodes by thoracotomy;
with insertion of pulse generator
Insertion or repositioning of electrode lead(s) for single or dual chamber pacing cardioverter-defibrillator and insertion of pulse generator
|33262||Removal of pacing cardioverter-defibrillator pulse generator with replacement of pacing cardioverter-defibrillator pulse generator; single lead system|
|33263||Removal of pacing cardioverter-defibrillator pulse generator with replacement of pacing cardioverter-defibrillator pulse generator; dual lead system|
|33264||Removal of pacing cardioverter-defibrillator pulse generator with replacement of pacing cardioverter-defibrillator pulse generator; multiple lead system|
|33270||Insertion or replacement of permanent subcutaneous implantable defibrillator system, with subcutaneous electrode, including defibrillation threshold evaluation, induction of arrhythmia, evaluation of sensing for arrhythmia termination, and programming or reprogramming of sensing or therapeutic parameters, when performed (new code 1/1/15)|
|33271||Insertion of subcutaneous implantable defibrillator electrode (new code 1/1/15)|
|33272||Removal of subcutaneous implantable defibrillator electrode (new code 1/1/15)|
|33273||Repositioning of previously implanted subcutaneous implantable defibrillator electrode (new code 1/1/15)|
|93282, 93283, 93284; 93260||Programming device evaluation (in person) with iterative adjustment of the implantable device to test the function
of the device and select optimal permanent programmed values with analysis, review and report by a physician or other qualified health care professional, codes specific to the type of device
|93289;93261||Interrogation device evaluation (in person) with analysis, review and report by a physician or other qualified health care professional, includes connection, recording and disconnection per patient encounter; codes specific to the type of device|
|93640,93641, 93642, 93644||Electrophysiologic evaluation; codes specific to the type of device|
|0319T||Insertion or replacement of subcutaneous implantable defibrillator system with subcutaneous electrode (code deleted 12/31/14)|
|0320T||Insertion of subcutaneous defibrillator electrode (code deleted 12/31/14)|
|0321T||Insertion of subcutaneous implantable defibrillator pulse generator only with existing subcutaneous electrode (code deleted 12/31/14)|
|0322T||Removal of subcutaneous implantable defibrillator pulse generator only (code deleted 12/31/14)|
|0323T||Removal of subcutaneous implantable defibrillator pulse generator with replacement of subcutaneous implantable defibrillator pulse generator only (code deleted 12/31/14)|
|0324T||Removal of subcutaneous defibrillator electrode (code deleted 12/31/14)|
|0325T||Repositioning of subcutaneous implantable defibrillator electrode and/or pulse generator (code deleted 12/31/14)|
|0326T||Electrophysiologic evaluation of subcutaneous implantable defibrillator (includes defibrillation threshold evaluation, induction of arrhythmia, evaluation of sensing for arrhythmia termination, and programming or reprogramming of sensing or therapeutic parameters) (code deleted 12/31/14)|
|0327T||Interrogration device evaluation (in person) with analysis, review and report, includes connection, recording and disconnection per patient encounter; implantable subcutaneous lead defibrillator system (code deleted 12/31/14)|
|0328T||Programming device evaluation (in person) with iterative adjustment of the implantable device to test the function of the device and select optimal permanent programmed values with analysis; implantable subcutaneous lead defibrillator system (code deleted 12/31/14)|
Implantation or replacement of automatic cardioverter/defibrillator, total system (AICD), code includes pocket formation, thoracotomy;
Implantation, AICD leads only
Implantation, AICD pulse generator only
Replacement, AICD leads only
Replacement, AICD pulse generator only
|425.1;425.4||Hypertrophic cardiomyopathy codes|
Paroxysmal ventricular tachycardia
Cardiac dysrhythmia, unspecified (ventricular arrhythmia code)
|745.0-745.9||Bulbus cordis anomalies and anomalies of cardiac septal closure code range|
|746.0-746.9||Other congenital anomalies of heart code range|
Cardioverter-defibrillator, dual chamber (implantable)
|C1722||Cardioverter-defibrillator, singel chamber (implantable)|
|C1882||Cardioverter-defibrillator, other than single or dual chamber (implantable)|
|ICD-10-CM (effective 10/1/15)||I42.1-I42.2||Hypertrophic cardiomyopathy code range|
|I46.2, I46.8, I46.9||Cardiac arrest code range|
|I49.9||Cardiac arrhythmia, unspecified|
|Q20.0-Q20.9||Congenital malformations of cardiac chambers and connections code range|
|Q21.0-Q21.9||Congenital malformations of cardiac septa code range|
|Q22.0-Q22.9||Congenital malformations of pulmonary and tricuspid valves code range|
|Q23.0-Q23.9||Congenital malformations of aortic and mitral valves code range|
|Q24.0-Q24.9||Other congenital malformations of heart code range|
|ICD-10-PCS (effective 10/1/15)||ICD-10-PCS codes are only used for inpatient services.|
|02H40ME, 02H43ME, 02H44ME, 02H60ME, 02H63ME, 02H64ME, 02H70ME, 02H73ME, 02H74ME, 02HK0ME, 02HK3ME, 02HK4ME, 02HL0ME, 02HL3ME, 02HL4ME, 02HN0ME, 02HL3ME, 02HL4ME, 02HN0ME, 02HN3ME, 02HN4ME||Surgical, heart & great vessels, insertion, defibrillator lead, code by body part and approach|
|0JH60P4, 0JH63P4, 0JH80P4, 0JH83P4||Surgical, subcutaneous tissue & fascia, insertion, defibrillator generator, code by body part and approach|
|02PA0MZ, 02PA3MZ, 02PA4MZ, 02PAXMZ,||Surgical, heart & great vessels, removal, cardiac lead, code by approach|
|0JPT0PZ, 0JPT3PZ||Surgical, subcutaneous tissue & fascia, removal, cardiac rhythm related device, trunk, code by approach|
Type of Service
Place of Service
Automatic Implantable Cardioverter Defibrillator
Cardioverter Defibrillator, Automatic Implantable
Defibrillator, Automatic Implantable Cardioverter
Implantable Cardioverter Defibrillator, Automatic
|03/31/96||Add to Surgery section||New policy|
|08/18/00||Replace policy||Archived policy|
|07/12/02||Replace policy||Revision of existing policy based on 2002 TEC Assessment|
|12/17/03||Replace policy||Literature review update; revised ACC guidelines and Medicare coverage policy added; policy statement unchanged|
|11/9/04||Replace policy||Policy updated with October 2004 TEC Assessment findings (embargoed pending publication of SCD-HeFT); policy statement changed to reflect TEC findings. Revised Medicare policy added|
|04/01/05||Policy updated further with October 2004 TEC Assessment after publication of SCD-HeFT and DINAMIT; policy statement changed to reflect TEC findings. Revised Medicare policy added|
|04/25/06||Replace policy||Literature review update for the period of February 2005 through February 2006; reference numbers 4 and 6 added. Policy statement unchanged|
|12/13/07||Replace policy||Policy updated with literature review through November 2007. Policy statement revised to indicate that use of ICD in certain high-risk patients with hypertrophic cardiomyopathy may be considered medically necessary. References 7-10 added.|
|11/13/08||Replcae policy||Policy updated with literature review; reference numbers 6 and 9 added; other references renumbered from prior version. Policy statements unchanged.|
|12/03/09||Replace policy||Policy updated with literature review; reference numbers 5 and 11 added/updated. Policy statements unchanged|
|09/08/10||coding update only||added HCPCS codes|
|5/12/11||Replace policy||Policy updated with literature review through January 2011; reference numbers 13 through 21 added, clinical input reviewed. Policy statements specific to ICD indications in pediatric patients added to policy statements and rationale. Policy statement regarding adult patients unchanged.|
|7/14/11||Replace policy||Policy statement revised to clarify the indications in ischemic cardiomyopathy with separate indications for class II/III and class I patients. Policy statement with waiting time in nonischemic cardiomyopathy was revised based on additional clinical input.|
|09/13/12||Replace policy||Policy statement added on the use of subcutaneous ICD, considered investigational for all indications. References 12, 14, 19, 24-26 added, including ACCF/AHA guidelines on management of patients with HCM.|
|11/8/12||Replace policy- correction only||Information about FDA approval of the subcutaneous ICD added to the regulatory section and references to lack of FDA approval for subcutaneous ICD devices removed.|
|10/10/13||Replace policy||Policy updated with literature review through August 31, 2013. References 13, 25, 27, and 29 added. No change to policy statements.|
|3/13/14||Replace policy||Revision to policy statement made for clarity through August 2013. A clause “…after reversible causes (eg, acute ischemia) have been excluded” added to current statement on secondary prevention in adults.|
|10/09/14||Replace policy||Policy updated with literature review through September 7, 2014. References 1, 16-17, 23, 31, 33, and 35-39 added. Rationale section reorganized. Policy statements unchanged.|