Cardiovascular rehabilitation with a WCD

Previous studies established arole for the wearable cardioverter defibrillator (WCD) to effectively and safely bridge temporary risk for sudden cardiac death (SCD) in patients with advanced heart failure. The prognostic relevance of the WCD remains controversial. The authors investigated adherence to, as well as the safety and effectiveness of, WCD use in areal-world cohort of patients at high risk for SCD. All consecutive patients (n = 83) receiving aWCD at aGerman tertiary care hospital between April 2012 and December 2019 were retrospectively included in this analysis. Patient characteristics were collected at the time of the index hospitalization. Using the Zoll® lifeVest® (ZOLL Medical Corporation, Chelmsford, MA, USA) network database, two separate investigators evaluated adherence to the WCD as well as arrhythmic events during WCD wear time. During 3680 wearing days (mean WCD wear time, 44days) with amedian daily wear time of 23.1 h, three arrhythmic events of relevance (sustained ventricular tachycardia, VT) occurred, one of which was sufficiently terminated by WCD shock. Another patient died from sudden cardiac death while pausing his WCD. Right bundle branch block correlated significantly with sustained VT occurrence (r = 0.3315; 95% CI -0.1265 to 0.3014; p = 0.0022). In 30patients (36.1%) acardioverter/defibrillator was implanted. In areal-life clinical setting, the use of WCD in patients at high risk for sudden cardiac death is effective and safe and adherence to the device is high. The event rate for VA was lower than in comparable patient cohorts. Adherence remains acrucial issue as one patient in the present series died while not wearing the device.

Background: The wearable cardioverter-defibrillator (WCD) is available for patients at high risk for sudden cardiac death (SCD) when immediate implantable cardioverter-defibrillator (ICD) implantation is not possible or indicated. Patient selection remains challenging especially in primary prevention. Long-term data on these patients is still lacking. Methods: 153 patients were included in this study. They were prescribed the WCD between April 2012 and March 2019 at the University Medical Center, Mannheim, Germany. The mean follow-up period was 36.2 ± 15.6 months. Outcome data, including all-cause mortality, were analyzed by disease etiology and ICD implantation following WCD use. Results: We analyzed 56 patients with ischemic cardiomyopathy, 70 patients with non-ischemic cardiomyopathy, 16 patients with prior need for ICD/CRT-D (device for cardiac resynchronization therapy with defibrillator) explanation, 8 patients with acute myocarditis and 3 patients with congenital diseases. 58% of the patients did not need ICD/CRT-D implantation after WCD use. 4% of all patients suffered from appropriate WCD shocks. 2 of these patients (33%) experienced appropriate ICD shocks after implantation due to ventricular tachyarrhythmias. Long-term follow-up shows a good overall survival. All-cause mortality was 10%. There was no significant difference between patients with or without subsequent ICD implantation (p = 0.48). Patients with ischemic cardiomyopathy numerically showed a higher long-term mortality than patients with non-ischemic cardiomyopathy (14% vs. 6%, p = 0.13) and received significantly more ICD shocks after implantation (10% of ischemic cardiomyopathy (ICM) patients versus 3% of non-ischemic cardiomyopathy (NICM) patients, p = 0.04). All patients with ventricular tachyarrhythmias during WCD use or after ICD implantation survived the follow-up period. Conclusion: Following WCD use, ICD implantation could be avoided in 58% of patients. Long-term follow-up shows good overall survival. The majority of all patients did not suffer from WCD shocks nor did receive ICD shocks after subsequent implantation. Patient selection regarding predictive conditions on long-term risk of ventricular tachyarrhythmias needs further risk stratification.

The WEARIT-II Registry demonstrated efficacy and safety of the wearable cardioverter defibrillator (WCD) for at-risk cardiac patients. However, 1-year outcomes in this population have not been reported. The WEARIT-II Registry enrolled 2,000 U.S. patients prescribed the WCD. One-year mortality data from start of WCD use were prospectively collected for 1,846 patients (93%). Outcome data were analyzed by disease etiology and implantable cardioverter defibrillator (ICD) implantation following WCD use. During 12 months of follow-up, 73 patients died (4%). Kaplan-Meier survival analysis showed differences in all-cause mortality from WCD prescription between patients with ischemic versus nonischemic cardiomyopathy versus congenital/inherited heart disease (4%vs 3%vs 7%, P=0.013). Patients with ventricular arrhythmia events during WCD use had a higher 1-year mortality (10%vs 3%, P=0.042). Renal disease, increasing age, prior syncope, and nonbeta-blocker use predicted mortality. One-year mortality was similar in patients who did versus did not receive an ICD following WCD use in ischemic (3%vs 4%, P=0.470) and nonischemic cardiomyopathy (3%vs 3%, P=0.892). Patients with congenital/inherited heart disease with no implanted ICD had a trend toward a higher rate of mortality than those who received an ICD (8%vs 3%, P=0.082). Multivariate models confirmed these findings. One-year follow-up from the WEARIT-II Registry shows an overall good survival in patients prescribed the WCD. Short-term use of WCD allows appropriate risk stratification for decision on an ICD implantation in at-risk ischemic and nonischemic cardiomyopathy patients. Congenital/inherited heart disease patients had a higher risk of 1-year mortality even without an implanted ICD post-WCD.

Prospective data on the safety and efficacy of the wearable cardioverter defibrillator (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 2014. 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 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.

Background Data on the use of the wearable cardioverter-defibrillator (WCD) among patients with myocarditis remain sparse. Consequently, evidence for guideline recommendations in this patient population is lacking. Methods and Results In total, 1596 consecutive patients were included in a multicenter registry from 8 European centers, with 124 patients (8%) having received the WCD due to myocarditis and reduced left ventricular ejection fraction or prior ventricular tachyarrhythmia. The mean age was 51.6±16.3 years, with 74% being male. Patients were discharged after index hospitalization on heart failure medication: Angiotensin-converting enzyme inhibitors (62.5%), angiotensin-receptor-neprilysin inhibitor (22.9%), aldosterone-antagonists (51%), or beta blockers (91.4%). The initial median left ventricular ejection fraction was 30% (22%-45%) and increased to 48% (39%-55%) over long-term follow-up (P<0.001). The median BNP (brain natriuretic peptide) level at baseline was 1702 pg/mL (565-3748) and decreased to 188 pg/mL (26-348) over long-term follow-up (P=0.022). The mean wear time was 79.7±52.1 days and 21.0±4.9 hours per day. Arrhythmic event rates documented by the WCD were 9.7% for nonsustained ventricular tachycardia, 6.5% for sustained ventricular tachycardia, and 0% for ventricular fibrillation. Subsequently, 2.4% of patients experienced an appropriate WCD shock. The rate of inappropriate WCD shocks was 0.8%. All 3 patients with appropriate WCD shock had experienced ventricular tachycardia/ventricular fibrillation before WCD prescription, with only 1 patient showing a left ventricular ejection fraction <35%. Conclusions Patients with myocarditis and risk for occurrence of ventricular tachyarrhythmia may benefit from WCD use. Prior ventricular arrhythmia might appear as a better risk predictor than a reduced left ventricular ejection fraction <35% in this population.

BackgroundThe wearable cardioverter-defibrillator (WCD) has emerged as a valuable tool to temporarily protect patients at risk for sudden cardiac death (SCD). The aim of this study was to determine the value of the WCD for therapy optimization of heart failure patients.MethodsOne hundred five consecutive patients that received WCD between 4/2012 and 9/2016 were included in the study. All patients were followed for clinical outcome and echocardiographic parameters during WCD therapy and had continued follow-up after WCD therapy, irrespective of subsequent implantable cardioverter-defibrillator (ICD) implantation.ResultsThe most common indication for WCD were newly diagnosed ischemic (ICM) or non-ischemic cardiomyopathy (NICM) with left ventricular ejection fraction (LVEF) ≤35%. Mean WCD wear time was 68.8 ± 50.4 days with a mean daily use of 21.5 ± 3.5 h. Five patients (4.8%) received a total of five appropriate WCD shocks.During WCD wear, patients with ICM and NICM showed significant improvement in LVEF, reducing the proportion of patients with a need for primary preventive ICD implantation to 54.8% (ICM) and 48.8% (NICM). An ICD was finally implanted in 51.4% of the study patients (24 trans-venous ICDs, 30 subcutaneous ICDs).After discontinuation of WCD therapy, all patients were followed for a mean of 18.6 ± 12.3 months. 5.6% of patients with implanted ICDs received appropriate therapies. No patient with subcutaneous ICD needed change to a trans-venous device. None of the patients without an implanted ICD suffered from ventricular tachyarrhythmias and no patient died suddenly.In patients with NICM a significant LVEF improvement was observed during long-term follow-up (from 34.8 ± 11.1% to 41.0 ± 10.2%).ConclusionsWCD therapy successfully bridged all patients to either LVEF recovery or ICD implantation. Following WCD, ICD implantation could be avoided in almost half of the patients. In selected patients, prolongation of WCD therapy beyond 3 months might further prevent unnecessary ICD implantation. The WCD as an external monitoring system contributed important information to optimize device selection in patients that needed ICD implantation.

Wearable cardioverter-defibrillator as a bridge to cardiac transplantation: A national database analysis

Article, see p 635 The wearable cardioverter-defibrillator (WCD) was approved by the US Food and Drug Administration in 2001. Since then, use of the WCD has grown steadily, and the device is now also available in Australia, Europe, Israel, Japan, and Singapore. Earlier this year, the American Heart Association published a science advisory that rated the use of the WCD as it is reasonable (Class IIa) or may be considered (Class IIb) in several specific patient categories.1 At this point, many clinicians worldwide wonder if the WCD has become standard of care. Are we delivering inadequate care if we do not offer the WCD to our patients? The WCD received US Food and Drug Administration approval (as durable medical equipment) primarily on the basis of the demonstration of shock efficacy in controlled laboratory settings. The first systematic clinical evaluation was the WEARIT/BIROAD study (Wearable Defibrillator Investigative Trial and Bridge to ICD in Patients at Risk of Arrhythmic Death), a nonrandomized, noncontrolled series published in 2004.2 It followed up 289 patients at high risk for sudden cardiac death (SCD) who were given the WCD. In this population, 6 of 8 (75%) defibrillation attempts were successful. The 6 sudden deaths all occurred in patients not wearing the WCD as instructed. This was the first study to demonstrate the feasibility and reasonable efficacy of the WCD. Since the WEARIT/BIROAD study, there has been a steady stream of observational research supporting the use of the WCD in a variety of clinical settings. It has been studied specifically in patients with recent myocardial infarction (MI), newly diagnosed cardiomyopathy, recent revascularization, peripartum cardiomyopathy, nonischemic cardiomyopathy, congenital structural heart disease, and inherited arrhythmias.3–8 Aggregate US nationwide data from the manufacturer (ZOLL, Pittsburg, PA) registry have also been reported.9 These data showed …

Post-Shock Asystole in Patients Dying Out of Hospital While Wearing a Cardioverter Defibrillator

Cardiac arrest is a vexing public health problem. Fortunately, implantable cardioverter-defibrillators (ICDs) have been proven to decrease overall mortality in several populations at high risk for cardiac arrest. However, it is still unclear how to treat patients who have an elevated risk of cardiac arrest but are not in one of the identified high-risk groups proven to benefit from an ICD. It also is uncertain how to manage high-risk patients who have an accepted indication for an ICD but are unable or unwilling to have an ICD. In these clinical situations, the wearable defibrillator and automatic external defibrillator are options that should be considered. Both devices have been shown in small series to be highly effective at restoring sinus rhythm in patients with a ventricular tachyarrhythmia. However, there is still a lack of large-scale trials proving that these devices should be employed routinely in specific high-risk patient populations.

Aims We aimed to provide contemporary real-world data on wearable cardioverter-defibrillator (WCD) use, not only in terms of effectiveness and safety but also compliance and acceptability.Methods and results Across 88 French centres, the WEARIT-France study enrolled retrospectively patients who used the WCD between May 2014 and December 2016, and prospectively all patients equipped for WCD therapy between January 2017 and March 2018. All patients received systematic education session through a standardized programme across France at the time of initiation of WCD therapy and were systematically enrolled in the LifeVest Network remote services. Overall, 1157 patients were included (mean age 60 ± 12 years, 16% women; 46% prospectively): 82.1% with ischaemic cardiomyopathy, 10.3% after implantable cardioverter-defibrillator explant, and 7.6% before heart transplantation. Median WCD usage period was 62 (37–97) days. Median daily wear time of WCD was 23.4 (22.2–23.8) h. In multivariate analysis, younger age was associated with lower compliance [adjusted odds ratio (OR) 0.97, 95% confidence interval (CI) 0.95–0.99, P < 0.01]. A total of 18 participants (1.6%) received at least one appropriate shock, giving an incidence of appropriate therapy of 7.2 per 100 patient-years. Patient-response button allowed the shock to be aborted in 35.7% of well-tolerated sustained ventricular arrhythmias and in 95.4% of inappropriate ventricular arrhythmia detection, finally resulting in an inappropriate therapy in eight patients (0.7%).ConclusionOur real-life findings reinforce previous studies on the efficacy and safety of the WCD in the setting of transient high-risk group in selected patients. Moreover, they emphasize the fact that when prescribed appropriately, in concert with adequate patient education and dedicated follow-up using specific remote monitoring system, compliance with WCD is high and the device well-tolerated by the patient.

BackgroundThis study aimed to investigate the rate of early improvement in ejection fraction (EF) within 21 - 60 days among patients with cardiomyopathy who were provided with a wearable cardioverter defibrillator (WCD).MethodsThis was a retrospective study of patients who received a WCD at our institution to determine the rate of improvement in left ventricular EF (LVEF) to ≥ 35-40%. Among 990 patients who received a WCD during the study period, 101 had an echocardiogram performed during the subsequent 21 - 60 days. Patients were stratified according to their initial EF, as well as age, gender, number of heart failure medications, and ischemic vs. nonischemic cardiomyopathy. Multivariate logistic regression analysis was performed to assess the influence of these variables on the subsequent improvement in EF.ResultsThere were 39 patients who had improvement in their EF to ≥ 35-40%. The only significant predictor of EF recovery was the initial EF. There was a direct correlation between initial EF category and the likelihood of improvement in EF. For every unit increase in initial EF category, the odds of improvement increased 1.73 times (95% confidence interval (CI): 1.22 - 2.45). Age (P = 0.20), gender (P = 0.10), ischemic cardiomyopathy (P = 0.40), and number of heart failure medications at the time of WCD placement (P = 0.26) were not significant predictors of improved LVEF.ConclusionsThis study showed a rate of improvement in EF to ≥ 35-40% of 39% within 21 - 60 days of placement of a WCD among patients with both ischemic and nonischemic cardiomyopathy. The only significant clinical predictor of EF improvement was initial EF.

A specific analysis of patients from the STICH trial (Surgical Treatment of Ischaemic Heart Failure) revealed that the risk of sudden cardiac death (SCD) in coronary artery bypass graft surgery patients with severely impaired left ventricular (LV) function is highest between the first and third month postoperatively [1]. According to current guidelines, the indication for permanent implantable cardioverter defibrillator (ICD) therapy should be evaluated 90 days post-revascularization and bridging this time period with a wearable cardioverter defibrillator (WCD) may be reasonable [2]. The reported study results of Kuehn et al. [3] in this issue of the journal support the importance of early postoperative WCD bridging in cardiac surgical patients with severely impaired LV function to reduce or eliminate the risk of SCD. In total, 9.1% of 1168 patients had at least one episode of ventricular arrhythmia while wearing the WCD and 1.5% received an adequate and effective shock. No ineffective therapy occurred and the inadequate shock rate was low at 0.7%.

While the implantable cardioverter-defibrillator (ICD) has been proven to be the best choice for patients with long-term risk for sudden cardiac arrest/sudden cardiac death (SCA/SCD), the question is how to manage patients with only temporary risk, e.g., during the guidelines-recommended waiting period until the decision for an ICD can be made. These patient groups should be monitored around the clock to guarantee a lifesaving shock within a few minutes, if necessary.These conditions can be accomplished by the wearable cardioverter-defibrillator (WCD) in the outpatient sector. The WCD is worn on the skin and consists of four nonadhesive ECG electrodes as well as three defibrillation electrodes-two at the back and one at the front-embedded in a garment. The defibrillation unit is connected via a cord and can be worn over the shoulder or on a belt. Cardiac events can be recorded and retrospectively analyzed by the treating physician.The WCD is a safe and effective measure to terminate potentially lethal ventricular tachycardia and ventricular fibrillation. It may be used early after myocardial infarction with reduced left ventricular ejection fraction (LVEF), as well as for patients with acute heart failure in nonischemic cardiomyopathy with uncertain cause and prognosis. In addition, it may be used for patients waiting for heart transplantation, for patients who cannot be implanted an ICD due to comorbidities, and for patients after explantation of their ICD, e.g., because of infection until reimplantation.One may expect that risk stratification of patients with the WCD will lead to even better selection for ICD use.

The implantable cardiac defibrillator (ICD) has been an effective tool for prevention of sudden cardiac death (SCD) in populations at high risk for life-threatening sustained ventricular tachycardia (VT) and ventricular fibrillation (VF). However, ICD implantation is dependent on defining ventricular substrate, evaluating the future risk of SCD and estimation of the patient’s overall survival. The ability to predict risk of SCD is often difficult. If ventricular dysfunction (a surrogate marker for the risk of SCD) improves, ICD therapy may not be indicated. The wearable cardiac defibrillator (WCD) provides an option for protection during this vulnerable period when the risk of SCD is unclear. It combines an electrocardiogram-monitoring system with an external automatic defibrillator. The WCD can be a safe and effective tool for prevention of VT/VF related SCD events and is used in a variety of clinical situations where the risk of SCD is changing. Such situations include the early phase after acute myocardial infarction with poor left ventricular function (≤35%), after acute coronary revascularization procedures and reduced left ventricular ejection fraction (≤35%), acute heart failure and non-ischemic cardiomyopathy of uncertain duration and prior to medical therapy initiation. The WCD also has a role in patients waiting for heart transplantation or who need a ventricular-assist device and those who have an acute contra-indication to implantation such as active infection. This review discusses the technical aspects of the WCD, its potential clinical application and summarizes the currently available data on the WCD in different populations and future directions.