Prior authorization is recommended for wearable cardioverter defibrillators. Prior authorization is NOT recommended for IMPLANTABLE cardioverter defribrillators. To authorize, call Blue Cross and Blue Shield of Montana (BCBSMT) Customer Service at 1-800-447-7828 or fax your request to the Medical Review Department at 406-437-7863. A retrospective review is performed if services are not prior authorized.
BCBSMT may consider the use of wearable cardioverter-defibrillators for the prevention of sudden cardiac death medically necessary as interim treatment for those who:
- meet the criteria for an implantable cardioverter-defibrillator; and
- have a temporary contraindication to receiving an ICD, such as a systemic infection, at the current time; and
- have been scheduled for an ICD placement or who had an ICD removed and have been rescheduled for placement of another ICD once the contraindication is treated.
BCBSMT considers the use of wearable cardioverter-defibrillators for the prevention of sudden cardiac death investigational for all other indications, including use immediately (i.e., less than 40 days) following an acute myocardial infarction.
Federal mandate prohibits denial of any drug, device, or biological product fully approved by the FDA as investigational for the Federal Employee Program (FEP). In these instances coverage of these FDA-approved technologies are reviewed on the basis of medical necessity alone. Call the BCBSMT FEP Customer Service Department at 1-800-634-3569 for benefit information.
It is uncommon for patients to have a temporary contraindication to ICD placement. The most common reason will be a systemic infection that requires treatment before the ICD can be implanted. The wearable cardioverter-defibrillator should only be used short-term while the temporary contraindication (e.g., systemic infection) is being clinically managed. Once treatment is completed, the permanent ICD should be implanted.
In July 2003, HCPCS codes became effective that are specific to this device:
The following CPT code describes the professional services involved in the initial set-up and programming of this device: 93745
In 2009, a new CPT code was introduced to describe interrogation of a wearable cardioverter-defibrillator device: 93292
Code 93292 cannot be reported with code 93745.
The purpose of medical policy is to guide coverage decisions and is not intended to influence treatment decisions. Providers are expected to make treatment decisions based on their medical judgment. BCBSMT recognizes the rapidly changing nature of technological development and welcomes provider feedback on all medical policies.
When using this policy to determine whether a service, supply or device will be covered, please note that member contract language will take precedence over medical policy when there is a conflict.
This policy was created in 2008 and updated with periodic literature reviews, the most recent covering the period between August 2011 and August 2012.
The available evidence on the wearable cardioverter-defibrillator (WCD) consists of case series describing outcomes from patients using the device. There are no randomized controlled trials (RCTs) of WCD compared to standard care or alternative treatments. Randomized controlled trials of patients undergoing permanent ICD implantation can provide indirect evidence on the efficacy of the WCD if the indications for a permanent ICD are similar to the potential indications for WCD and if the performance of the WCD has been shown to approximate that of a permanent ICD.
FDA-labeled indications for the device are adult patients who are at risk for sudden cardiac arrest (SCA) and either are not candidates for or refuse an implantable cardioverter-defibrillator (ICD). (1) Some experts (2) have suggested that the indications for a WCD should be broadened to include other populations at high risk for SCA. These potential indications include:
- Bridge to transplantation (i.e., the WEARIT population)
- Bridge to implantable device or clinical improvement (i.e., the BIROAD population)
- Postbypass with ejection fraction less than 30%
- Postbypass with ventricular arrhythmias or syncope within 48 hours of surgery
- Postmyocardial infarction with ejection fraction less than 30%
- Postmyocardial infarction with ventricular arrhythmias within 48 hours
- Drug-related arrhythmias (during drug washout or after, during evaluation of long-term risk)
- Patients awaiting revascularization
- Patients too ill to undergo device implantation
- Patients who refuse device therapy
Is the WCD effective in detecting and terminating ventricular arrhythmias for high-risk patients, compared to an implantable device?
There are very few peer-reviewed published studies that report on clinical outcomes of WCDs and no studies that evaluate the efficacy of WCD in reducing mortality compared to alternatives. Despite the small amount of evidence, a TEC Assessment completed in 2010 (3) concluded that the evidence is sufficient to conclude that the WCD can successfully terminate malignant ventricular arrhythmias. First, there is strong physiologic rationale for the device. It is known that sensor leads placed on the skin can successfully detect and characterize arrhythmias. It is also established that a successful counter shock can be delivered externally. The use of external defibrillators is extensive, ranging from in-hospital use to public placement and use at home. The novelty of this device is in the way that it is packaged and utilized.
Second, there is a small amount of evidence that supports that the device successfully terminates arrhythmias. Two uncontrolled studies were identified that directly tested the efficacy of the WCD. The first (4) was a small case series of 15 patients who were survivors of SCA and scheduled to receive an ICD. During the procedure to implant a permanent ICD, or to test a previously inserted ICD, patients wore the WCD while clinicians attempted to induce ventricular arrhythmias. Of the 15 patients, 10 developed ventricular tachycardia (VT) or ventricular fibrillation (VF). The WCD correctly detected the arrhythmia in 9 of 10 cases and successfully terminated the arrhythmia in all 9 cases.
The WEARIT/BIROAD study (5) was a prospective cohort study that evaluated 289 patients at high risk for sudden cardiac death (SCD) but who did not meet criteria for an ICD or who could not receive an ICD for several months. A total of 289 patients were enrolled and followed for a mean of 3.1 months. During this time, there were 8 documented episodes of arrhythmia requiring shock in 6 separate patients. Six of the 8 episodes were successfully resuscitated by the WCD. By group sequential analysis, the estimate of percent successful resuscitations was 69%. There was 99% confidence that the true rate of success was greater than 25% and 90% confidence that the true rate was greater than 44%. In the 2 cases of unsuccessful defibrillation, the authors reported that the WCD was placed incorrectly, with the therapy electrodes reversed and not directed to the skin.
The WEARIT/BIROAD results underscore the difficulty in proper use and compliance with the device. Six patients suffered SCA that was likely due to wearing the device improperly or not wearing the device at all. This implied that a relatively high rate of nonadherence may be the main factor limiting the effectiveness of the WCD. Also, there was a fairly high rate of dropout (22%) over the approximately 3 months of follow-up. These results suggest that the WCD is likely to be inferior to an ICD, due to suboptimal adherence and difficulty with correct placement of the device. Therefore, these data corroborate the assumption that the WCD should not be used as a replacement for an ICD but only considered in those situations in which the patient does not meet criteria for a permanent ICD.
Conclusions. There are no studies that directly compare the performance of a WCD with a permanent ICD. One small study in the electrophysiology lab demonstrated that the WCD can correctly identify and terminate most induced ventricular arrhythmias. A cohort study of WCD use estimated that the percent of successful resuscitations was approximately 70%. In that study, there was a high rate of non-adherence and dropouts, and failures to successfully resuscitate were largely attributed to incorrect use of the device and/or non-adherence. This evidence indicates that the WCD can successfully detect and terminate arrhythmias in at least some patients but that the overall performance in clinical care is likely to be inferior to a permanent ICD.
Does the WCD improve outcomes when used as a bridge to permanent ICD placement or clinical improvement in the following situations, compared to usual care?
- Temporary contraindications to implantable cardioverter-defibrillator
- Immediate post-MI period
- High-risk patients post-CABG [coronary artery bypass graft] surgery
- High-risk patients awaiting heart transplantation
- Newly diagnosed non-ischemic cardiomyopathy
- Peripartum cardiomyopathy
Temporary contraindications to implantable cardioverter-defibrillator
Contraindications to an ICD are few. According to the American College of Cardiology/American Heart Association/ (ACC/AHA) guidelines on ICD use, the device is contraindicated in patients with terminal illness, with drug-refractory class IV heart failure, who are not candidates for transplantation, and in patients with a history of psychiatric disorders that interfere with the necessary care and follow-up postimplantation. (6) It is not known how many patients refuse an ICD after it has been recommended for them.
There is a small number of patients who meet established criteria for an ICD (see policy No. 7.01.44) but have a transient (i.e., short-term) contraindication for an implantable device. The most common contraindication is an infectious process that precludes insertion or when an ICD is removed due to infection, and there must be a delay before reinsertion to treat the infection. The WCD may have benefit in this group, if the device is able to successfully detect and abort ventricular arrhythmias in this population.
The WCD avoids potential complications associated with ICD implantation, but complication rates with current techniques for ICD placement are low. In 1 large trial of ICD versus antiarrhythmic drug therapy, (7) complications of ICD implantation in 507 patients included hematomas in 13 (2.6%), bleeding requiring transfusion or reoperation in 6 (1.2%), infection in 10 (2.0%), pneumothorax in 8 (1.6%), and cardiac perforation in 1 (0.2%). Early mortality (within 30 days of procedure) was not higher for the ICD group (2.4%), compared to the medication group (3.5%).
Immediate post-MI period
The evidence on the use of a WCD as a bridge to permanent ICD placement was reviewed in a 2010 TEC Assessment. (3) The most common of these indications is for patients who are in the immediate post- myocardial infarction (MI) period. For these patients, indications for a permanent ICD cannot be reliably assessed immediately post-MI, since it is not possible to determine the final ejection fraction until at least 30 days after the event. Since the first 30 days following an acute MI represent a high-risk period for lethal ventricular arrhythmias, there is a potential to improve mortality by using other treatments to prevent SCS.
Despite the rationale for this potential indication, the TEC Assessment concluded that the available evidence does not support the contention that any cardioverter-defibrillator improves mortality in patients in the immediate post-MI period. One post-hoc analysis of an RCT and 2 prospective RCTs were reviewed that led to this conclusion.
Secondary analysis of data from the MADIT-II trial evaluated whether an ICD improves mortality in the early post-MI period. (8) MADIT-II randomly assigned 1,159 patients with prior MI and an ejection fraction of less than 30% to an ICD or control and showed an overall mortality benefit for patients treated with an ICD. The secondary analysis examined the benefit of ICD according to length of time from the original MI and showed that the benefit of ICD was dependent on the length of time since the original MI. Within the first 18 months post-MI, there was no benefit found for ICD implantation (hazard ratio [HR]: 0.97; 95% confidence interval [CI]: 0.51-1.81, p=0.92). In contrast, there was a significant mortality benefit when the length of time since MI was greater than 18 months (HR: 0.55; 95% CI: 0.39-0.78, p=0.001).
Two RCTs were specifically designed to address the question of early ICD use post-MI. The DINAMIT study (9) evaluated the utility of an automatic ICD (AICD) for this patient population. This trial randomly assigned 342 patients with an acute MI and an ejection fraction of 35% or less. The primary outcome was death from any cause, and a predefined secondary outcome was death from an arrhythmia. After a mean follow-up of 30 months, there was no difference in overall survival for the ICD group compared to control (HR: 1.08; 95% CI: 0.76-1.55, p=0.66). There was a significant difference for the ICD group in the secondary outcome of death from arrhythmia (HR: 0.42; 95% CI: 0.22-0.83, p=0.009). The decrease in deaths from arrhythmias for the ICD group was offset by a corresponding increase in deaths due to nonarrhythmic, cardiac causes. The authors suggest that the discrepancy in these outcomes may arise from the fact that patients in whom the ICD successfully aborted an arrhythmia may have eventually died from other cardiac causes, such as progressive heart failure.
The IRIS trial (10) was similar in design to the DINAMIT trial. This study included 998 patients who were 5 to 31 days post-MI and had at least 1 other high-risk factor, either nonsustained ventricular tachycardia or a resting pulse greater than 90. Patients were followed for a mean of 37 months. Results of the IRIS trial were similar to DINAMIT, with no difference in overall mortality between the ICD and control groups (26.1% vs. 25, respectively.8%, p=0.76). The ICD group had a decreased rate of SCD (6.1% vs. 13.2%, respectively, p=0.049), which was offset by a higher rate of nonsudden cardiac death (15.3% vs. 8.6%, respectively, p=0.001). This study also reported noncardiac death, which was similar for the ICD and control groups (4.7% vs. 4.0%, respectively, p=0.51).
High-risk patients post-CABG surgery
One randomized controlled trial (CABG PATCH) (11) evaluated early ICD placement in high-risk postcoronary artery bypass graft surgery (CABG) patients, selected by a low left ventricular ejection fraction (LVEF) and abnormalities on signal-averaged electrocardiogram (EKG). The trial followed patients for a mean of 32 months and reported on overall mortality. Results of this trial indicated no difference in overall mortality between the ICD and control groups (HR: 1.07; 95% CI: 0.81–1.42). There were no other mortality outcomes reported. There was a higher rate of infections in the ICD group, both deep sternal infections (2.7 vs. 0.4%, respectively, p<0.05) and superficial wound infections (12.3 vs. 5.9%, respectively, p<0.05). The cumulative incidence of inappropriate shocks was 50% at 1 year and 57% at 2 years.
High-risk patients awaiting heart transplantation
There are no studies that are specifically address this population of patients, but some patients awaiting transplantation have been included in studies with mixed populations. The WEARIT/BIROAD study, discussed previously, was a prospective cohort study that included patients awaiting transplant, but it also included other high-risk patients and did not report separately on the population of patients awaiting transplant. (5) Rao et al. (12) published a case series of 162 patients with either congenital structural heart disease or inherited arrhythmias treated with WCD. Approximately one-third of these patients had a permanent ICD, which was explanted due to infection or malfunction. The remaining patients used the WCD either as a bridge to heart transplantation, during an ongoing cardiac evaluation, or in the setting of surgical or invasive procedures that increased the risk of arrhythmias. There were 4 patient deaths during a mean duration WCD treatment of approximately 1 month, but none of these were related to cardiac causes. Two patients received a total of 3 appropriate shocks for ventricular tachycardia (VT)/ventricular fibrillation (VF), and 4 patients received a total of 7 inappropriate shocks. The results of this study suggest that the WCD can be worn safely and can detect arrhythmias in this population, but the rate of inappropriate shocks is relatively high.
Newly diagnosed non-ischemic cardiomyopathy
Another potential indication for the WCD is in patients with newly diagnosed nonischemic cardiomyopathy. Similar to acute MI, in these patients the final ejection fraction is uncertain, since some patients who are newly diagnosed with nonischemic cardiomyopathy show an improvement in ejection fraction over the ensuing several months. A post-hoc analysis of the DEFINITE trial, (13) which evaluated the use of an ICD in nonischemic dilated cardiomyopathy, examined the benefit of ICD use by time since diagnosis. This trial excluded patients with a clinical picture consistent with a reversible cause of cardiomyopathy and thus may differ from the population considered for a WCD. For the overall DEFINITE trial, there was a 35% reduction in overall mortality, but this difference did not meet statistical significance. In the re-analysis, patients were divided into recent diagnosis of cardiomyopathy (less than 3 months) and remote diagnosis (greater than 9 months). The difference in survival was of borderline significance for the ICD group compared to controls, both for the recently diagnosed subgroup (HR 0.38; 95% CI: 0.14–1.00, p=0.05), and the remotely diagnosed subgroup (HR 0.43; 95% CI: 0.22–0.99, p=0.046).
One study of WCD use in peripartum cardiomyopathy was published in 2012. (14) This study included 107 women with peripartum cardiomyopathy treated with a WCD device during the period of 2003 through 2009. Patients were identified from a registry of WCD use maintained by the manufacturer of the device. The average length of time that the WCD was used was 124+123 days. During this time, there were no shocks delivered, either appropriate shocks or inappropriate shocks. There were also no patient deaths during the time of WCD treatment. Following discontinuation of the WCD, there were 3 deaths over a mean follow-up of 3.0+1.2 years. In a matched group of 159 women with non-ischemic cardiomyopathy who wore the WCD for 96+83 days, there were 2 appropriate shocks and 11 deaths.
Conclusions. For patients with indications for an ICD but temporary contraindications, the use of a WCD for a temporary period of time is likely to improve outcomes. These patients are expected to benefit from an ICD, and the use of a WCD is a reasonable alternative as there are no other options for automatic detection and termination of ventricular arrhythmias.
Two RCTs of implantable cardioverter-defibrillator use in the early post-acute MI period concluded that mortality was not improved compared to usual care. In both these trials, sudden cardiac death was reduced in the ICD group, but non-sudden cardiac death was increased, resulting in no difference in overall mortality. One trial of high-risk post-CABG patients also reported no benefit from implantation of a permanent ICD. Since a permanent ICD does not appear to be beneficial in these situations, a WCD would also not be beneficial for these patient populations.
For other indications, evidence is lacking concerning the impact of a WCD on outcomes. Case series for these conditions are not sufficient to determine whether a WCD improves outcomes compared to usual care.
External automatic cardiac defibrillators
Home use of an automatic external cardiac defibrillator is another potential alternative to either an ICD or a wearable defibrillator. However, there are no clinical trials that establish the efficacy of automatic external defibrillators for high-risk patients. Bardy et al. (15) randomly assigned 7,001 patients with anterior wall MI, who were not candidates for ICD implantation, to home external defibrillator or usual care. After a median follow-up of 37.3 months, there was no difference in mortality between groups (HR 0.97, 95% CI: 0.81-1.17). Therefore, home external defibrillators may not be a good alternative to ICD or WCD in high-risk patients.
A search of online site www.ClinicalTrials.gov using the terms wearable cardioverter-defibrillator returned a total of 3 ongoing trials. Two of these are RCTs, which are described further below.
- VEST/PREDICTS (NCT00628966). This is an open-label RCT comparing WCD treatment to usual care in patients with recent acute MI and LV ejection fraction <35%. The primary outcome measure is mortality due to sudden death, and secondary outcomes are all-cause mortality, cardiovascular mortality, and other cause-specific mortality. The estimated enrollment is 2,400 patients, and study completion date is listed as December 2011.
- Vest Prevention of Sudden Death Trial (NCT01446965). This is an unblinded RCT comparing WCD treatment to usual care in patients with recent MI and LV ejection fraction <35%. The primary outcome measure is mortality due to sudden death. Secondary outcomes are all-cause mortality, cardiovascular mortality, other cause-specific mortality, incidence of ventricular arrhythmias, adverse events due to the WCD, and compliance with the device. Estimated study enrollment is 1,900 patients, and study completion date is listed as September 2015.
Clinical Input Received through Physician Specialty Societies and Academic Medical Centers
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.
In response to the request for input through Physician Specialty Societies and Academic Medical Centers, no input was received while this policy was under review for the April 2008 update.
In response to requests, input was received from no physician specialty societies and 4 academic medical centers while this policy was under review in 2010. Most, but not all, of those providing input suggested that the wearable defibrillator may have a role in selected high-risk patients following acute myocardial infarction or in newly diagnosed cardiomyopathy.
The available data establish that the WCD device can detect lethal arrhythmias and can successfully deliver a counter shock in most cases. There are a small number of patients who meet established criteria for an ICD but have a transient contraindication for an implantable device, most commonly an infectious process. In these patients who are scheduled for ICD placement, the WCD may be considered medically necessary as an interim treatment. The evidence shows that
- these patients benefit from a cardioverter-defibrillator in general; and
- the WCD can detect and treat lethal arrhythmias in these patients.
For other bridging indications, particularly for the immediate post-MI period, the evidence does not support the conclusion that the WCD improves outcomes. Two randomized controlled trials have reported that overall survival is not improved following treatment with a permanent ICD. While these two trials both reported a decrease in SCD, there was a corresponding increase in non-SCD, resulting in no net benefit in survival. Similarly, for high-risk post-CABG patients, one randomized controlled trial reported no difference in overall survival associated with early ICD placement. Thus, given the lack of evidence that a permanent ICD improves outcomes for these indications, a WCD is not expected to improve outcomes and is therefore considered investigational.
For other potential indications, there are only case series or no relevant published evidence. Therefore it is not possible to conclude from the available evidence that net health outcome will be improved. These other indications, including bridge to transplantation, newly diagnosed non-ischemic cardiomyopathy, and peripartum cardiomyopathy, are also considered investigational.
Clinical Practice Guidelines and Position Statements
Guidelines from the major cardiology specialty societies do not make specific recommendations for the use of WCD. For example, the most recent ACC/AHA guidelines on the treatment of patients with ventricular arrhythmias (16) includes the following statement on WCD but does not include a formal recommendation:
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