National Medical Policy

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1 National Medical Policy Subject: Policy Number: Cardiac Defibrillators - External, Automatic NMP269 Effective Date*: May 2006 Updated: May 2017 This National Medical Policy is subject to the terms in the IMPORTANT NOTICE at the end of this document For Medicaid Plans: Please refer to the appropriate State's Medicaid manual(s), publication(s), citations(s) and documented guidance for coverage criteria and benefit guidelines prior to applying Health Net Medical Policies The Centers for Medicare & Medicaid Services (CMS) For Medicare Advantage members please refer to the following for coverage guidelines first: Use Source Reference/Website Link National Coverage Determination (NCD) National Coverage Manual Citation X Local Coverage Determination (LCD)* Automatic External Defibrillators: X Article (Local)* Automatic External Defibrillators: Other None Use Health Net Policy Instructions Medicare NCDs and National Coverage Manuals apply to ALL Medicare members in ALL regions. Medicare LCDs and Articles apply to members in specific regions. To access your specific region, select the link provided under Reference/Website and follow the search instructions. Enter the topic and your specific state to find the coverage determinations for your region. *Note: Health Net must follow local coverage determinations (LCDs) of Medicare Administration Contractors (MACs) located Automatic External Cardiac Defibrillators May 17 1

2 outside their service area when those MACs have exclusive coverage of an item or service. (CMS Manual Chapter 4 Section 90.2) If more than one source is checked, you need to access all sources as, on occasion, an LCD or article contains additional coverage information than contained in the NCD or National Coverage Manual. If there is no NCD, National Coverage Manual or region specific LCD/Article, follow the Health Net Hierarchy of Medical Resources for guidance. Current Policy Statement Health Net, Inc. considers wearable cardioverter defibrillators (e.g., LifeVest) medically necessary when any of the following criteria is met: 1. There is a clear indication for an implanted/permanent device accompanied by a transient contraindication or interruption in ICD care such as infection; or 2. As a bridge to more definitive therapy such as cardiac transplantation; or 3. As bridging therapy in situations associated with increased risk of death in which ICDs have been shown to reduce SCD, but not overall survival such as within 40 days of MI; or 4. When there is concern about a heightened risk of SCD that may resolve over time or treatment of left ventricular dysfunction, for example, in ischemic heart disease with recent revascularization, newly diagnosed nonischemic dilated cardiomyopathy in a patient starting guideline-directed medical therapy, or secondary cardiomyopathy (tachycardia mediated, thyroid mediated,etc.) in which the underlying cause is potentially treatable. Note: This device is FDA approved for use in both adults and children. Individuals under the age of 18 must have a chest circumference of 26 inches and weigh at least 18.75kg (approximately 43 pounds, the average size of an 8 year old). Note: Please refer to the Health Net National Medical Policy on Cardiac Defibrillators, Automatic Implantable for additional information Not Medically Necessary Health Net, Inc. considers an automatic external defibrillator (AED) for use in the home, not medically necessary. There is a lack of prospective clinical trials in the published medical literature to determine the safety, efficacy or improved outcomes of the use of AEDs for use in the home by laypersons. An AED kept in the home is primarily considered a safety device or a precautionary measure to address a possible acute event, rather than a device for active treatment. Health Net, Inc. considers external defibrillators of any type, not medically necessary when any of the following contraindications exist: Irreversible brain damage from preexisting cerebral disease Any disease, other than cardiac disease (e.g., cancer, uremia, liver failure), associated with a likelihood of survival less than one year Unexplained syncope in the absence of structural heart disease or inducible ventricular tachycardia or ventricular fibrillation Incessant documented ventricular tachycardia or ventricular fibrillation Automatic External Cardiac Defibrillators May 17 2

3 Ventricular tachycardia or ventricular fibrillation due to a completely correctable cause Irreversible NYHA class IV congestive heart failure without option of cardiac transplantation Wearable Defibrillators such as the LifeVest (i.e., Zoll LifeVest, etc.) are not recommended for use in the following individuals: Those with vision or hearing problems that may make it difficult to perceive the alarms or messages from the WCD Those taking medications that may interfere with responding to the alarms of messages Those unwilling to wear the device continuously except when bathing Women who are pregnant or breastfeeding or attempting pregnancy Those exposed to high levels of electromagnetic interference that may prevent the WCD from operating Those who already have an implanted defibrillator NONWEARABLE AED (E0617) A device that automatically analyzes the heart rhythm and, if it detects a problem that may respond to an electrical shock, it permits a shock to be delivered to restore a normal heart rhythm. These devices have been installed in many settings, such as schools and airports. Codes Related To This Policy NOTE: The codes listed in this policy are for reference purposes only. Listing of a code in this policy does not imply that the service described by this code is a covered or noncovered health service. Coverage is determined by the benefit documents and medical necessity criteria. This list of codes may not be all inclusive. On October 1, 2015, the ICD-9 code sets used to report medical diagnoses and inpatient procedures have been replaced by ICD-10 code sets. ICD-9 Codes Acute myocardial infarction of anterolateral wall episode of care unspecified - acute myocardial infarction of unspecified site subsequent episode of care Endomyocardial fibrosis - secondary cardiomyopathy unspecified Hypertrophic obstructive cardiomyopathy Paroxysmal ventricular tachycardia Ventricular fibrillation Ventricular flutter Cardiac arrest Mechanical complication of automatic implantable cardiac defibrillator - infection and inflammatory reaction due to cardiac device implant and graft ICD-10 Codes I21.01-I21.09 ST elevation (STEMI) myocardial infarction of anterior wall I21.11-I21.19 ST elevation (STEMI) myocardial infarction of inferior wall I21.21-I21.29 ST elevation (STEMI) myocardial infarction of other sites I21.3 ST elevation (STEMI) myocardial infarction of unspecified sites Automatic External Cardiac Defibrillators May 17 3

4 I21.4 Non-ST elevation (NSTEMI) myocardial infarction I22.0-I22.9 Subsequent ST elevation (STEMI) and non-st elevation (NSTEMI) myocardial infarction I42.0-I42.9 Cardiomyopathy I46.2-I46.9 Cardiac Arrest I47.0-I47.9 Paroxysmal tachycardia I49.01-I49.02 Ventricular fibrillation and flutter T82.89-T Other specified complication of cardiac and vascular prosthetic devices, implants, and grafts CPT Codes Initial set-up and programming by a physician or other qualified health care professional of wearable cardioverter-defibrillator includes initial programming of system, establishing baseline electronic ECG, transmission of data to data repository, patient instruction in wearing system and patient reporting of problems or events HCPCS Codes A9999 E0617 K0606 K0607 K0608 K0609 Miscellaneous DME supply or accessory, not otherwise specified External defibrillator with integrated electrocardiogram analysis Automatic external defibrillator, with integrated elctrocardiogram analysis, garment type Replacement battery for automated external defibrillator, garment type only, each Replacement garment for use with automated external defibrillator, each Replacement electrodes for use with automated external defibrillator, garment type only, each Scientific Rationale Update May 2016 Per the American Heart Association (AHA) Science Advisory on wearable cardioverter-defibrillator (WCD) therapy (2016), Implantable cardioverter-defibrillators (ICDs) reduce mortality by 20-30% when implanted in patients who have received optimal medical therapy for 40 days (postacute myocardial infarction [AMI] or revascularization) or 90 days in nonischemic cardiomyopathy. Benefit from a primary prevention ICD is not time dependent either in nonischemic cardiomyopathy or after AMI, and a comparable risk for lifethreatening arrhythmias exists at virtually all windows of time after index event or diagnosis. Although early implantation of an ICD appears to decrease sudden cardiac death (SCD), the overall survival benefit from an ICD early after an MI or a new diagnosis of cardiomyopathy has not been observed. Nonetheless, there are high-risk patients who may derive survival benefit from early protection against SCD. WCD offers a bridge from diagnosis to a point in time when further improvement in left ventricular ejection fraction is unlikely. Additionally, WCD may be employed in patients with transient contraindications to ICD implantation such as ongoing infection. The detection algorithm used by the WCD has a sensitivity of % and a specificity of 98-99%. Inappropriate shock rates in early studies were approximately 1-2%. Once an arrhythmia has met the detection criteria, the patient receives vibratory, audible, and visual alerts and is able to abort the shock if he or she remains conscious. If no patient response is recorded, a shock is delivered. WCD Automatic External Cardiac Defibrillators May 17 4

5 shock energies range between 75 and 150 J biphasic. The response time (detection to shock) takes seconds. Shock efficacy rates are between 69% and 99%. WCD has no pacing capability. There are no completed randomized trials of WCD therapy. No definitive data are available on comparative efficacy versus alternative (or no) treatment. In the largest observational series to date, daily use was >90% in >50% of the cohort, and the device discontinuation rate was 14%. The AHA Advisory Panel make the following recommendations: WCDs may be appropriate as bridging therapy in situations associated with increased risk of death in which ICDs have been shown to reduce SCD, but not overall survival such as within 40 days of MI (Class IIb; Level of Evidence C). Use of wearable defibrillators is reasonable when there is a clear indication for an implanted/permanent device accompanied by a transient contraindication or interruption in ICD care such as infection (Class IIa; Level of Evidence C). Use of WCDs may be reasonable when there is concern about a heightened risk of SCD that may resolve over time or treatment of left ventricular dysfunction, for example, in ischemic heart disease with recent revascularization, newly diagnosed nonischemic dilated cardiomyopathy in a patient starting guidelinedirected medical therapy, or secondary cardiomyopathy (tachycardia mediated, thyroid mediated, etc) in which the underlying cause is potentially treatable (Class IIb; Level of Evidence C). Use of WCDs is reasonable as a bridge to more definitive therapy such as cardiac transplantation (Class IIa; Level of Evidence C). WCDs should not be used when nonarrhythmic risk is expected to significantly exceed arrhythmic risk, particularly in patients who are not expected to survive >6 months (Class III; Level of Evidence C). IIa-level of evidence C (Recommendation in favor of treatment or procedurebeing useful/effective. Only diverging expert opinion, case studies, or standard of care) IIB- level of evidence C (Recommendation s usefulness/efficacy less well established Only diverging expert opinion, case studies or standard of care). III, C: Recommendation that procedure or treatment is not useful/effective and may be harmful. Only expert opinion, case studies or standard of care. Per the 2015 ESC Guidelines on the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death, "In patients with transient impaired LVEF, the WCD may be used until LV function has recovered sufficiently, following insults such as MI, post-partum cardiomyopathy, myocarditis or interventions such as revascularization associated with transient LV dysfunction. Similarly, patients with a history or at risk of life- threatening VAs or who are scheduled for cardiac transplantation may be temporarily protected with the WCD." The guideline makes the following recommendation: The WCD may be considered for adult patients with poor LV systolic function who are at risk of sudden arrhythmic death for a limited period, but are not candidates for an implantable defibrillator (e.g. bridge to transplant, bridge to transvenous implant, Automatic External Cardiac Defibrillators May 17 5

6 peripartum cardiomyopathy, active myocarditis and arrhythmias in the early postmyocardial infarction phase). Class IIb recommendation, Level of evidence-c. (Usefulness/efficacy is less well established by evidence/opinion may be considered; Level of evidence C Consensus of opinion of the experts and/or small studies, retrospective studies, registries.) In December 2015, the U.S. Food and Drug Administration approved a new indication for the LifeVest wearable cardioverter defibrillator. The LifeVest is approved for certain children who are at risk for sudden cardiac arrest, but are not candidates for an implantable defibrillator due to certain medical conditions or lack of parental consent. The device is intended only for children that weigh at least 41 pounds and have a chest size of 26 inches or more, about the size of an average 8 year old. The approval was based on published studies and a company registery containing clinical information from 248 patients, ages 3 to 17, at risk for sudden cardiac arrest. No additional safety concerns were identified, and four patients who experienced sudden cardiac arrest received a shock that successfully restored a life-sustaining heartbeat. Salehi et al (2016) reported the wearable cardioverter defibrillator (WCD) is often used in patients at risk of sudden cardiac death (SCD) who are not yet candidates for an implantable cardioverter defibrillator (ICD). Newly diagnosed cardiomyopathy may be reversible, and a WCD may protect patients during the initial period of risk. The authors sought to evaluate the benefit and compliance of the WCD in patients with nonischemic cardiomyopathy (NICM). The authors reviewed a national database of patients with NICM who used WCDs and who self-reported a history of excess alcohol use, although other causes of cardiomyopathy could not be excluded. The database contained demographic data, initial ejection fraction (EF), reason for WCD prescription, compliance and use data, any detected arrhythmias, therapies, and reason for discontinuing WCD. Statistical analyses were performed using SAS, version 9.3 (SAS Institute, Cary, NC). Of the 127 patients, 88% were men with a mean age of 52.6 ± 11.0 years. The mean initial EF was 19.9% ± 7.4%. Patients wore the WCD for a median of 51 days and a median daily use of 18.0 hours per day. The most common reasons for discontinuing the WCD were improvement in EF (33%) or ICD implantation (23.6%). Seven patients (5.5%) had 9 sustained ventricular arrhythmia events, which were successfully treated with 100% conversion. There were 11 deaths (8.6%) during 100 days of follow-up. No deaths resulted from WCD shock failure or undersensing. The reviewers concluded NICM may have a significant risk of ventricular arrhythmias and death in the first few months. The WCD delivered appropriate therapy in 5.5% of patients. This study suggests that a WCD may be effective temporary prophylaxis for prevention of SCD in patients with newly diagnosed NICM. Singh et al (2015) reported the WCD has emerged as a means of protecting patients with newly diagnosed NICM or ischemic cardiomyopathy (ICM) against sudden cardiac death while awaiting re-evaluation of cardiac function. The study sought to characterize the risk of appropriate WCD therapy in newly diagnosed NICM and ICM patients according to cardiomyopathy etiology in an independent study. Medical records of all patients prescribed a WCD between June 2004 and May 2015 at the authors institution (n = 639) were analyzed, focusing on 254 patients with newly diagnosed NICM and 271 patients with newly diagnosed ICM. Patients with a prior implantable cardioverter-defibrillator or sustained ventricular arrhythmias were Automatic External Cardiac Defibrillators May 17 6

7 excluded (n = 114). The primary endpoint was appropriate WCD therapy. Median WCD wear time was 61 days (interquartile range [IQR]: 25 to 102 days) per patient and 22 h/day (IQR: 17 to 23 h/day). During 56.7 patient-years, 0 NICM patients received an appropriate WCD shock, whereas 3 (1.2%) received an inappropriate shock. During 46.7 patient-years, 6 (2.2%) ICM patients received an appropriate shock; 5 survived the episode, and 4 survived to hospital discharge. All 6 patients with an appropriate shock were male with QRS duration >120 ms. Two (0.7%) ICM patients received an inappropriate shock. The authors concluded in this independent, retrospective study, the risk of appropriate WCD therapies in patients with newly diagnosed NICM was minimal. Routine use of the WCD in this population should be prospectively evaluated. The risk of appropriate therapies in newly diagnosed ICM was comparable to that observed in prior observational studies. Kondo et al (2015) reported the effectiveness of the WCD therapy in early postmyocardial infarction (MI) patients remains uncertain. The authors analyzed the characteristics and outcomes of patients who received a WCD in the early post-mi phase. Twenty-four patients were followed-up for 8 months (range, 4-16 months). Two patients (8.3%) received appropriate shocks. Left ventricular ejection fraction improved after the WCD therapy (P<0.01). Fourteen patients (58%) received an implantable cardioverter defibrillator at the end of the follow-up period. The authors concluded early post-mi patients at high risk of sudden cardiac death may benefit from WCD therapy. Kutyifa et al (2015) reported prospective data on the safety and efficacy of the WCD in a real-world setting are lacking. The Prospective Registry of Patients Using the Wearable Defibrillator (WEARIT-II) Registry was designed to provide real-world data on the WCD as a strategy during a period of risk stratification. The WEARIT-II Registry enrolled 2000 patients with ischemic (n=805, 40%), or nonischemic cardiomyopathy (n=927, 46%), or congenital/inherited heart disease (n=268) prescribed WCD between August 2011 and February Clinical data, arrhythmia events, implantable cardioverter defibrillator implantation, and improvement in ejection fraction were captured. The median age was 62 years; the median ejection fraction was 25%. The median WCD wear time was 90 days, with median daily use of 22.5 hours. There was a total of 120 sustained ventricular tachyarrhythmias in 41 patients, of whom 54% received appropriate WCD shock. Only 10 patients (0.5%) received inappropriate WCD therapy. The rate of sustained ventricular tachyarrhythmias by 3 months was 3% among patients with ischemic cardiomyopathy and congenital/inherited heart disease, and 1% among nonischemic patients (P=0.02). At the end of WCD use, 840 patients (42%) were implanted with an implantable cardioverter defibrillator. The most frequent reason not to implant an implantable cardioverter defibrillator following WCD use was improvement in ejection fraction. The authors concluded the WEARIT-II Registry demonstrates a high rate of sustained ventricular tachyarrhythmias at 3 months in at-risk patients who are not eligible for an implantable cardioverter defibrillator, and suggests that the WCD can be safely used to protect patients during this period of risk assessment. Opreanu et al (2015) reported life-threatening ventricular arrhythmias (VAs) and SCD are common in patients awaiting heart transplantation (HT), and the ICD is often used for primary prevention in this setting. Use of ICDs in these patients is not without risks and is sometimes contraindicated. The WCD may be a reasonable alternative to bridge the period of risk leading up to HT. A convenience sample of patients prescribed an WCD as a bridge therapy to HT was obtained. The available data consisted of demographics, cardiac transplantation status, associated Automatic External Cardiac Defibrillators May 17 7

8 comorbidities, device use, device-stored electrocardiogram (ECG) and reason for discontinuing the WCD. Statistical analyses were performed using SPSS version 17 and GraphPad PRISM 5. The registry included 121 patients consisting of 83 (69%) men and 38 (31%) women. The mean age was 44 ± 18 years. Mean ejection fraction was 25 ± 15%. Non-ischemic cardiomyopathy (CMP) was the underlying diagnosis in 67 (55%) patients, whereas 21 (17%) patients had ischemic CMP and 33 (27%) had a mixed or uncharacterized CMP. New York Heart Association Class III heart failure was present in 32% and 34% were in Class IV. Eighty-eight patients (73%) were being evaluated for HT or were on an HT waiting list, and 33 patients (27%) had had a prior HT, experienced rejection, and were awaiting re-transplantation. The patients wore the WCD for an average of 127 ± 392 days (median 39 days) with average daily use of 17 ± 7 hours (median 20 hours). Seven patients (6%) received appropriate WCD shocks. Fifty-one patients (42%) ended use after ICD implantation and 13 patients (11%) after HT. There were 11 deaths (9%). The authors concluded a significant proportion of patients on the HT waiting list will have VA. WCD use in our study showed high compliance and efficacy and a low complication rate, suggesting that the WCD is a reasonable bridge therapy for preventing SCD in patients awaiting HT. Several clinical trials are currently recruiting participants to evaluate WCD for various indications and can be found at clinicaltrial.gov. Scientific Rationale Update May 2015 Wan et al. (2014) A study was completed in which all hemodialysis (HD) patients who were prescribed a wearable cardioverter defibrillator (WCD) between 2004 and 2011 and experienced at least one SCA event were included in this study. Demographics, clinical background, characteristics of sudden cardiac arrest (SCA) events were identified from the manufacturer's database. An SCA event was defined as all sustained ventricular tachycardia/fibrillation (VT/VF) or asystole occurring within 24 hours of the index arrhythmia episode. The social security death index was used to determine mortality after WCD use. A total of 75 HD patients (mean age = 62.9 ± 11.7 years, female = 37.3%) experienced 84 SCA events (119 arrhythmia episodes) while wearing the WCD. Sixty six (78.6%) SCA events were due to VT/VF and 18 (21.4%) were due to asystole. Most SCA episodes occurred between 09:00 and 10:00 (RR = 2.82, 95% CI [1.05, 7.62], P < ), followed by the 13:00-14:00 time interval (RR = 2.22, 95% CI [0.79, 6.21], P = 0.006). Acute 24-hour survival was 70.7% for all SCA events; 30-day and 1-year survival were 50.7% and 31.4%, respectively. Women had a better post-sca survival than men (HR = 2.41, 95% CI [1.09, 5.36], P = 0.03). The use of WCD in HD patients was associated with improved post-sca survival when compared to historical data. Uyei et al. (2014) completed a systematic literature review with the objectives to identify all published literature on wearable defibrillators, assess the wearable defibrillator's efficacy and effectiveness in general and among specific patient groups, including post-myocardial infarction, post coronary artery bypass grafting or percutaneous coronary intervention, non-ischemic cardiomyopathy, and ischemic cardiomyopathy, and to evaluate the quality of evidence. The search and synthesis was informed by the Preferred Reporting Items for Systematic Reviews and Meta- Analyses statement, and the quality of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation and the Newcastle Ottawa Scale. A total of thirty-six articles and conference abstracts from thirty-three studies were included in the review. It appears that wearable defibrillator use compared with no defibrillator use reduces the chance of ventricular tachycardia and Automatic External Cardiac Defibrillators May 17 8

9 ventricular fibrillation (VT/VF) associated deaths by an absolute risk reduction of approximately 1 percent, achieved by averting approximately 4/5th of all VT/VF associated deaths. The quality of evidence was low to very low quality, such that our confidence in the reported estimates is weak. To validate beneficial results, further investigation using robust study designs conducted by independent researchers is warranted. There is a Clinical Trial on Vest Prevention of Early Sudden Death Trial and VEST Registry, which is currently recruiting participants. The Clincialtrials.gov identifier is NCT , and it was last updated April 7, This purpose of the study is to explore the hypothesis that wearable defibrillators can impact mortality by reducing sudden death during the first three months after a heart attack in persons with high risk for life-threatening arrhythmias. The Sponsor is the University of California, San Francisco, and the Collaborator is Zoll Medical Corporation, the manufacturer of the device. The estimated primary completion date is September Per UpToDate (2015) Definitive treatment of out-of-hospital sudden cardiac sudden cardiac arrest (SCA) with early defibrillation was limited by the small number of qualified rescuers who could interpret cardiac rhythms. Since automatic external defibrillators (AEDs) analyze cardiac rhythms and directly inform rescuers whether a shock is indicated, their advent has allowed lay rescuers to provide early defibrillation. Scientific Rationale Update May 2013 The LifeVest is a wearable cardioverter defibrillator (WCD) developed by Lifecor Inc., Later acquired by Zoll Medical Corp and more recently (2012) acquired by Asahi Kasei Corp. Zishiri et al (2013) reported implantation of implantable cardioverter defibrillator for prevention of sudden cardiac death is deferred for 90 days after coronary revascularization, but mortality may be highest early after cardiac procedures in patients with ventricular dysfunction. They determined mortality risk in post revascularization patients with left ventricular ejection fraction 35% and compared survival with those discharged with a wearable cardioverter defibrillator (WCD). Hospital survivors after surgical (coronary artery bypass graft surgery) or percutaneous (percutaneous coronary intervention [PCI]) revascularization with left ventricular ejection fraction 35% were included from Cleveland Clinic and national WCD registries. Kaplan-Meier, Cox proportional hazards, propensity score-matched survival, and hazard function analyses were performed. Early mortality hazard was higher among 4149 patients discharged without a defibrillator compared with 809 with WCDs (90-day mortality post-coronary artery bypass graft surgery 7% versus 3%, P=0.03; post-pci 10% versus 2%, P<0.0001). WCD use was associated with adjusted lower risks of long-term mortality in the total cohort (39%, P<0.0001) and both post-coronary artery bypass graft surgery (38%, P=0.048) and post-pci (57%, P<0.0001) cohorts (mean follow-up, 3.2 years). In propensity-matched analyses, WCD use remained associated with lower mortality (58% post-coronary artery bypass graft surgery, P=0.002; 67% post-pci, P<0.0001). Mortality differences were not attributable solely to therapies for ventricular arrhythmia. Only 1.3% of the WCD group had a documented appropriate therapy. Investigators concluded patients with left ventricular ejection fraction 35% have higher early compared to late mortality after coronary revascularization, particularly after PCI. As early hazard seemed less marked in WCD users, prospective studies in this high-risk population are indicated to confirm whether WCD use as a bridge to left ventricular ejection fraction Automatic External Cardiac Defibrillators May 17 9

10 improvement or implantable cardioverter defibrillator implantation can improve outcomes after coronary revascularization. Kao et al (2012) reported heart failure (HF) patients have a high risk of death, and implantable cardioverter defibrillators (ICDs) are effective in preventing sudden cardiac death (SCD). However, a certain percentage of patients may not be immediate candidates for ICDs, particularly those having a short duration of risk or an uncertain amount of risk. This includes the newly diagnosed patients, as well as those on the cardiac transplant list or NYHA class IV heart failure patients who do not already have an ICD. In these patients, a wearable cardioverter defibrillator (WCD) may be used until long term risk of SCD is defined. The purpose of this study was to determine the incidence of SCD in this population, and the efficacy of early defibrillation by a WCD. Ten enrolling centers identified 89 eligible HF patients who were either listed for cardiac transplantation, diagnosed with dilated cardiomyopathy, or receiving inotropic medications. Data collected included medical history, device records, and outcomes (including 90 day mortality). Out of 89 patients, final data on 82 patients has been collected. Patients wore the device for 75±58 days. Mean age was 56.8±13.2, and 72% were male. Most patients (98.8%) were diagnosed with dilated cardiomyopathy with a low ejection fraction (<40%) and twelve were listed for cardiac transplantation. Four patients were on inotropes. There were no sudden cardiac arrests or deaths during the study. Interestingly, 41.5% of patients were much improved after WCD use, while 34.1% went on to receive an ICD. Investigators concluded the WCD monitored HF patients until further assessment of risk. The leading reasons for end of WCD use were improvement in left ventricular ejection fraction (LVEF) or ICD implantation if there was no significant improvement in LVEF. Several clinical trials of the LifeVest are currently recruiting participants. Scientific Rationale Update May 2012 There is a Clinical Trial currently recruiting participants on the Study of the Wearable Defibrillator in Heart Failure Patients (SWIFT). The study is sponsored by the Zoll Medical Corporation with the identifier of NCT The purpose of the study is to evaluate the safety and efficacy of wearable defibrillator use in patients with left ventricular dysfunction or advanced heart failure symptoms, who have a high-risk for sudden cardiac death but are either not eligible for an implantable defibrillator under current guidelines or are not able to receive the device due to their condition. The estimated study completion date is September Scientific Rationale Update January 2010 Chung et al (2010) investigated patient compliance and effectiveness of antiarrhythmic treatment by the wearable cardioverter-defibrillator (WCD). Effectiveness of the WCD for prevention of sudden death is dependent on event type, patient compliance, and appropriate management of ventricular tachycardia/ventricular fibrillation (VT/VF). Compliance and events were recorded in a nationwide registry of post-market release WCDs. Survival, using the Social Security Death Index, was compared with survival in implantable cardioverterdefibrillator (ICD) patients. Of 3,569 patients wearing the WCD (age 59.3+/-14.7 years, duration 52.6+/-69.9 days), daily use was 19.9+/-4.7 h (>90% of the day) in 52% of patients. More days of use correlated with higher daily use (p<0.001). Eighty sustained VT/VF events occurred in 59 patients (1.7%). First-shock success was 76 of 76 (100%) for unconscious VT/VF and 79 of 80 (99%) for all VT/VF. Eight patients Automatic External Cardiac Defibrillators May 17 10

11 died after successful conversion of unconscious VT/VF (89.5% survival of VT/VF events). Asystole occurred in 23 (17 died), pulseless electrical activity in 2, and respiratory arrest in 1 (3 died), representing 24.5% of sudden cardiac arrests. During WCD use, 3,541 of 3,569 patients (99.2%) survived overall. Survival occurred in 72 of 80 (90%) VT/VF events and 78 of 106 (73.6%) for all events. Long-term mortality was not significantly different from first ICD implant patients but highest among patients with traditional ICD indications. The investigators concluded compliance was satisfactory with 90% wear time in >50% of patients and low sudden death mortality during use. Survival was comparable to that of ICD patients. However, asystole was an important cause of mortality in sudden cardiac arrest events. Collins et al (2010) investigated the use of a wearable defibrillator in the pediatric population in a retrospectivey clinical database review, comparing a wearable defibrillator in patients 18 years of age to those aged years. There were 81 patients 18 years of age (median age = 16.5 years [9-18] and 52% male). There were 103 patients aged years (median age = 20 years [19-21] and 47% male). There was no difference between groups in average hours/day or in total number of days the patients wore the defibrillator. In patients 18 years of age, there was one inappropriate therapy and one withholding of therapy due to a devicedevice interaction. In patients aged years, there were five appropriate discharges in two patients and one inappropriate discharge in a single patient. The investigator concluded it is reasonable to consider the wearable automated external defibrillator as a therapy for pediatric patients who are at high risk of sudden cardiac arrest but who have contraindications to or would like to defer placement of a permanent ICD, however, as there were no appropriate shocks in our patients 18 years of age, the study cannot address efficacy of the therapy. Everitt and Saarel (2010) also investigated the use of a wearable cardiac defibrillator (WCD) in 4 children < 18 at a single center. Patient information regarding diagnosis, clinical history, electrocardiograms, rhythm reports, and outcome at last follow-up was reviewed. Information regarding the WCD was obtained including indication for use, patient compliance, and accuracy of rhythm determination, inappropriate and appropriate shock events, and other complications. None of the patients had an inappropriate shock. Two patients had documented noncompliance with wear, which resulted in failure to detect and treat a life-threatening arrhythmia in one. Two patients required downsizing of the WCD during use in order to improve electrode contact and rhythm detection. The reviewers concluded the WCD is an option for children of appropriate size who are at increased risk for sudden cardiac death, but in whom the risk of ICD implantation outweighs the benefit. Careful patient selection and education is important to ensure safety, as noncompliance with wear was common in this series of children. In August 2009, the FDA approved next generation of wearable defibrillators designed to be smaller, lighter, and more user-friendly. The device, as modified, will be marketed under the trade name Lifevest Wearable Defibrillator and is indicated for adult patients who are at risk for sudden cardiac arrest and are not candidates for or refuse an implantable defibrillator. Scientific Rationale Update October 2009 Sudden cardiac death (SCD) is typically defined as unanticipated death due to cardiac causes that occurs within 1 hour of the onset of acute symptoms. The American Heart Association estimates that 325,000 die each year from heart disease Automatic External Cardiac Defibrillators May 17 11

12 and SCD outside of a hospital setting. Most of these are sudden deaths caused by cardiac arrest related to ventricular fibrillation. Early defibrillation through drug treatment or through electrical shocks delivered by an implanted or external device is instrumental in surviving an episode of ventricular fibrillation. Of those who receive defibrillation during the first minute, 97% survive, but the survival rate drops to 15% to 40% for defibrillation in minutes 4 to 5, and to only 5% survival for interventions given 10 minutes or more after the incident. (Hayes, 2008) Implantable Cardiac Defibrillators have been extensively studied and the efficacy is well documented throughout the medical literature. Some patients who are at risk for SCD, however, do not meet established criteria for implantation of an ICD or may require only short-term protection (such as patients awaiting subsequent ICD insertion or cardiac transplantation). In such settings, a wearable cardioverterdefibrillator may be preferable to either ICD insertion or layperson resuscitation. The efficacy of the wearable cardioverter-defibrillator has been evaluated in a twocomponent clinical trial. One component (the WEARIT study) enrolled 177 patients with NYHA class III or IV heart failure and an ejection fraction <30 percent. The other component (the BIROAD study) enrolled 112 patients with a recent myocardial infarction or recent coronary artery bypass grafting who were considered to be at high risk of SCD but did not meet criteria for an ICD or who met criteria for an ICD but had refused implantation. The reported results indicated that 7 SDCs occurred while the vest was worn. All 7 were correctly diagnosed but only 5 were successfully treated as 2 patients had reversed the electrodes. During the studies, 12 patients died. Six deaths were not sudden, 5 deaths occurring when the patients were not wearing the vests and one patient died because the electrodes were reversed. Six inappropriate shock episodes occurred during 901 months of patient use (0.67% unnecessary shocks per month). Of the 289 subjects, 65 (22 percent) stopped using the device because of discomfort or inconvenience; 17 patients reported skin rash or itching. A 48 center clinical trial entitled Evaluating the Effectiveness of the LifeVest Defibrillator and Improving Methods for Determining the Use of Implantable Cardioverter Defibrillators (The VEST/PREDICTS Study NCT ) began in The trial is sponsored by the National Heart Lung and Blood Institute and the manufactures of various cardioverter/defibrillator devices, and is scheduled end in This two-part study will evaluate the effectiveness of the LifeVest in preventing death caused by an arrhythmia in the 2 months after an MI (VEST) and the second follows participants for several years after receiving and ICD. The study will also develop methods to determine who may benefit the most from receiving an ICD (PREDICTS). Subjects (4500 in total) with recent MI are randomly assigned to two groups: One group will have Life vest for 2 3 months and the second group will have the usual care post MI. The primary outcome of the VEST study is all-cause mortality. The primary outcome of the PREDICTS study is the occurrence of ventricular arrhythmias (30 beats of ventricular tachycardia/ventricular fibrillation). Secondaruy outcomes include: cardiovascular and other cause specific mortality; non fatal cardiovascular events; ventricular arrhythmias; adverse events; compliance; quality of life; resource utilization and cost. Automatic External Cardiac Defibrillators May 17 12

13 Scientific Rationale Update June 2009 The use of automated external defibrillators (AEDs) by trained lay responders in community-based public-access defibrillation programs has been shown to increase survival after sudden cardiac arrest. However, what effect the use of the device has on overall mortality for the community at risk is unknown. The purpose of the Home Automated External Defibrillator Trial (HAT), sponsored by the National Heart, Lung, and Blood Institute was to test whether an AED in the home of patients at intermediate risk of sudden cardiac arrest could improve survival. The Home Automated External Defibrillator Trial [Bardy et al (2008)] randomly assigned 7001 patients with previous anterior-wall myocardial infarction who were not candidates for an implantable cardioverter-defibrillator to receive one of two responses to sudden cardiac arrest occurring at home: either the control response [calling emergency medical services and performing cardiopulmonary resuscitation (CPR)] or the use of an AED, followed by calling emergency medical services and performing CPR. The primary outcome was death from any cause. The median age of the patients was 62 years; 17% were women. The median follow-up was 37.3 months. Overall, 450 patients died: 228 of 3506 patients (6.5%) in the control group and 222 of 3495 patients (6.4%) in the AED group. Mortality did not differ significantly in major prespecified subgroups. Only 160 deaths (35.6%) were considered to be from sudden cardiac arrest from tachyarrhythmia. Of these deaths, 117 occurred at home; 58 at-home events were witnessed. AEDs were used in 32 patients. Of these patients, 14 received an appropriate shock, and 4 survived to hospital discharge. There were no documented inappropriate shocks. The investigators concluded that for survivors of anterior-wall myocardial infarction who were not candidates for implantation of a cardioverter-defibrillator, access to a home AED did not significantly improve overall survival, as compared with reliance on conventional resuscitation methods Scientific Rationale Update June 2007 The LiveVest (WCD3000S) wearable defibrillator is an external cardiac defibrillator, which received FDA premarket approval on May 3, The most recent supplemental approval (P S007) was issued on November 1, This device was modified from the previous WCD 2000 noted in this policy; it is indicated for adult patients who are at risk for sudden cardiac arrest and are not candidates for or refuse an implantable defibrillator. The LifeVest (WCD3000S) is a combination of two different devices, a cardioverter and a defibrillator, similar to the WCD2000 system. It is the defibrillatory functionality of the device that is most critical because of mortality associated with fibrillation. If a life-threatening arrhythmia is detected, the nonadhesive therapeutic electrodes release a conductive gel and deliver a shock. Alarms sound prior to shock delivery, and if the patient is conscious the device may be disarmed. The potential patient population consists of adults who are at high risk for sudden cardiac arrest (SCA) and sudden cardiac death (SCD), but who are not suitable candidates for or who refuse an ICD. A cardiologist or other licensed physician prescribes the LifeVest, and monitors the patient, and a technician trains the patient on use of the vest and its associated equipment. A study was performed to examine the safety and efficacy of the LifeVest WCD system; this involved two smaller populations that consisted of patients waiting for a Automatic External Cardiac Defibrillators May 17 13

14 heart transplant, or those waiting for ICD implantation. Patients used the LifeVest WCD for approximately 94 days and a mean daily wear time of 19.1 hours. There were 7 SCA events when the LifeVest was being worn and all 7 were correctly diagnosed, but only 5 were successfully treated; 2 patients had assembled the system with reversion of the defibrillating electrodes. These results suggest that the true resuscitation rate was between 43% and 90%, based on a ventricular tachyarrhythmia detection rate of 85% to 95% and a defibrillation success rate of 50% to 95%. In this pivotal study, the inappropriate defibrillation shock rate was 0.69% per patient month, but no arrhythmias were induced because of these inappropriate shocks. The available data suggest that the LifeVest WCD might be a safe and effective defibrillator for resolving ventricular tachyarrhythmia in appropriate patients; however, a second large confirmatory study of the LifeVest WCD system is needed before definitive conclusions can be drawn regarding its safety and effectiveness in the general population. Evidence in the published medical literature on the safety and efficacy of wearable cardiac defibrillators (WCDs) is limited. These devices should therefore be limited to the small subset of patients at high risk for SCD who meet criteria for ICD placement but in whom the procedure is currently not indicated, such as those awaiting heart transplantation, awaiting ICD reimplantation following infection-related explantation, or patients with a systemic infectious process or other temporary condition that precludes implantation. The WCD may also be appropriate as a bridge to ICD risk stratification and possible implantation for patients in the immediate post-mi period who have either a history of ventricular tachycardia or ventricular fibrillation at least 48 hours after the acute MI, or a left ventricular ejection fraction 40%. Scientific Rationale - Initial Automatic external defibrillators (AEDs) are external devices that can monitor and assess cardiac rhythms, detect dysrhythmias, and deliver an automatic shock to the heart when appropriate. Their function is similar to implantable cardiac defibrillators without the patient having to undergo any invasive procedures. The U.S. Food and Drug Administration (FDA) approved the Lifecor WCD 2000 system via premarket application approval in December 2001 for "adult patients who are at risk for cardiac arrest and are either not candidates for or refuse an implantable defibrillator." Wearable The WCD 2000 System is a microprocessor-based and programmable patient-worn device that is designed to sense cardiac function and automatically deliver electrical therapy to treat ventricular arrhythmias. It consists of a vest that is to be worn continuously under the patients clothing to monitor the patient for potentially life threatening arrhythmias such as ventricular tachycardia (VT) or fibrillation (VF). If the device detects VT or VF above a programmable pre-set rate, it is capable of delivering a defibrillating pulse to the heart through the electrodes in an attempt to restore an effective rhythm. The wearable components include a monitor, battery pack, alarm module, electrode belt, garment and holster. The non-wearable components include a batter charger, modem, mode cable, computer cable, diagnostic tester, and the WCDNET. The WCDNET is a web-based data storage and retrieval system that allows physicians to access patient data using a web browser and Internet connection. An authorized physician or operator can view and print electrocardiogram events and generate reports related to patient wear-time and overall WCD 2000 monitoring performance. Automatic External Cardiac Defibrillators May 17 14

15 The WCD 2000 System communicates with the patient through voice and display messages, tones, or alarms and vibration against the skin. When an arrhythmia is detected, the device communicates with the patient verbally and with a series of alarms to stop the impending shock by pressing a response button to avoid receiving a shock while conscious. The device is deigned to deliver an electrical shock therapy pulse within 60 seconds of the onset of VT or VF unless a conscious patient presses the response button. FDA approval was based of the Lifecor WCD 2000 system was based on clinical data submitted to the FDA by the manufacturer, which has subsequently been published in the peer-reviewed literature, and referred to as the BIROAD and WEARIT studies. The trials consisted of prospective non-randomized studies, which compared the outcomes of the WCD with historical controls of patients suffering sudden cardiac arrest who called 911 emergency services. The study concluded that the WCD could detect arrhythmias and appropriately deliver a counter shock, however, its efficacy depends on the patient wearing the device appropriately at all times. The study concluded that an implantable cardiac defibrillator (ICD) is considered the gold standard. The WCD would be considered an alternative to an ICD only in the small subset of patients who have co-morbidities or other contraindications for an ICD. Nonwearable The nonwearable automatic external defibrillator (AED) is a compact, portable device that is used to deliver an electrical shock to a victim of SCA. AED units use a microprocessor inside a portable defibrillator to interpret a victim's heart rhythm through adhesive electrodes. The computer recognizes ventricular fibrillation (VF) or ventricular tachycardia (VT) and either advises the operator that electrical defibrillation is needed or automatically delivers a countershock. In 2004, the FDA granted marketing clearance for the over-the-counter sale of the HeartStart Home Defibrillator, which was previously available for home use with a prescription. The FDA based its decision on a review of data submitted by the manufacturer that demonstrated the AED could be used by lay people without medical supervision. Mortality data was not collected. In 2005, the Canadian Coordinating Office for Health Technology Assessment published an assessment of AEDs in the home setting, including the HeartStart Home Defibrillator, and concluded, No prospective studies demonstrate that the use of AEDs in the home by untrained persons improves health outcomes. Further investigation is needed to determine the benefit and harm of AEDs in the home. Review History May 2006 June 2007 June 2009 October 2009 January 2011 September 2011 Medical Advisory Council Initial Approval Added the LifeVest (WCD3000S) wearable defibrillator as medically necessary in select patients, who meet criteria noted under Wearable guidelines Updated - no revision Updated no revision Added Medicare table and link to LCD. No change to policy for commercial members. Update. Added Revised Medicare Table. No Revisions. Automatic External Cardiac Defibrillators May 17 15