End Of Wearable Cardioverter-defibrillator Use Research Articles

Real-world single center experience with the wearable cardioverter defibrillator: sex differences in risk stratification for sudden cardiac death

Abstract Background Wearable cardioverter defibrillator (WCD) demonstrated an important role for prevention of sudden cardiac death in patients with advanced heart failure and reduced left ventricular ejection fraction. Although in randomized trial there are no gender difference in WCD use and defibrillator (ICD) implantation rate, real world data in female patients is lacking. Purposes: We aimed to describe the sex differences in WCD use, the rate of cardiac events detected with WCD and the rate of ICD implantation after WCD use in women in a real-world single center experience. nd reduced left ventricular ejection fraction or prior ventricular tachyarrhythmia. Methods and results According with the current guidelines indications, between August 2017 and June 2023 ninety-six consecutive patients (mean age 66.0±11.1 years) received a WCD at Piacenza Hospitals and were retrospectively included in this analysis. There were no differences in clinical characteristics between female (18 patients, 18,8%) and male: in particular baseline left ventricular ejection fraction (LV EF) were similar between the two groups (29.5±5.2 vs 27.9±7.9, p=0.23) and no differences were found in the rate of ischaemic cardiopathy (66,6% vs 69,2% p=0.51). After 3-months follow up with WCD use, a similar rate of ventricular arrhythmias were found in the two groups (5.5% vs 3.8%, p=0.48) and no ventricular fibrillation was detected. The WCD usage period and median daily wear time were not different between female and male (55.2±50.6 vs 56.2±34.8 days p=0.53, 21.0±6.4 vs 23.1±1.5 hours p=0.48, respectively). However women presented a better LV EF improvement (12.2±9.7 vs 7.2±6.8, p=0.01), with a significant lower ICD implantation rate at the end of WCD use (55.5% vs 43.8%; p< 0.01) Conclusions In this real word analysis women presented a nice compliance using WCD. In spite of a similar burden of ventricular arrhythmic events, women presented a better LV EF improvement with a significant lower ICD implantation rate.

REAL–WORLD SINGLE CENTER EXPERIENCE WITH THE WEARABLE CARDIOVERTER DEFIBRILLATOR: SEX DIFFERENCES IN RISK STRATIFICATION FOR SUDDEN CARDIAC DEATH

Abstract Background Wearable cardioverter defibrillator (WCD) demonstrated an important role for prevention of sudden cardiac death in patients with advanced heart failure and reduced left ventricular ejection fraction. Although in randomized trial there are no gender difference in WCD use and defibrillator (ICD) implantation rate, real world data in female patients is lacking. Purposes: We aimed to describe the sex differences in WCD use, the rate of cardiac events detected with WCD and the rate of ICD implantation after WCD use in women in a real–world single center experience with reduced left ventricular ejection fraction or prior ventricular tachyarrhythmia. Methods and Results According with the current guidelines indications, between August 2017 and June 2023 ninety–six consecutive patients (mean age 66.0±11.1 years) received a WCD at Piacenza Hospitals and were retrospectively included in this analysis. There were no differences in clinical characteristics between female (18 patients, 18,8%) and male: in particular baseline left ventricular ejection fraction (LV EF) were similar between the two groups (29.5±5.2 vs 27.9±7.9, p=0.23) and no differences were found in the rate of ischaemic cardiopathy (66,6% vs 69,2% p=0.51). After 3–months follow up with WCD use, a similar rate of ventricular arrhythmias were found in the two groups (5.5% vs 3.8%, p=0.48) and no ventricular fibrillation was detected. The WCD usage period and median daily wear time were not different between female and male (55.2±50.6 vs 56.2±34.8 days p=0.53, 21.0±6.4 vs 23.1±1.5 hours p=0.48, respectively). However women presented a better LV EF improvement (12.2±9.7 vs 7.2±6.8, p=0.01), with a significant lower ICD implantation rate at the end of WCD use (55.5% vs 43.8%; p< 0.01). Conclusions In this real word analysis women presented a nice compliance using WCD. In spite of a similar burden of ventricular arrhythmic events, women presented a better LV EF improvement with a significant lower ICD implantation rate.

Sex differences in achieving guideline-recommended heart rate control among a large sample of patients at risk for sudden cardiac arrest

BackgroundDespite known clinical benefits, guideline-recommended HR control is not achieved for a significant proportion of patients with HF and reduced ejection fraction. The Wearable Cardioverter Defibrillator (WCD) provides continuous heart rate (HR) monitoring and alerts that could aid medication titration. ObjectiveThis study sought to evaluate sex differences in achieving guideline-recommended HR control during a period of WCD use. MethodsData from patients fitted with a WCD from 2015 to 2018 were obtained from the manufacturer´s database (ZOLL, Pittsburgh, PA). The proportion of patients with adequate nighttime resting HR control at the beginning of WCD use (BOU) and at the end of WCD use (EOU) were compared by sex. Adequate HR control was defined as having a nighttime median HR <70 bpm. ResultsA total of 21,440 women and a comparative sample of 17,328 men (median 90 days of WCD wear, IQR 59-116) were included in the final dataset. Among patients who did not receive a shock, over half had insufficient HR control at BOU (59% of women, 53% of men). Although the proportion of patients with resting HR ≥70 improved by EOU, 43% of women and 36% of men did not achieve guideline-recommended HR control. ConclusionsA significant proportion of women and men did not achieve adequate HR control during a period of medical therapy optimization. Compared to men, a greater proportion of women receiving WCD shocks had insufficiently controlled HR in the week preceding VT/VF and 43% of non-shocked women, compared to 36% of men, did not reach adequate HR control during the study period. The WCD can be utilized as a remote monitoring tool to record HR and inform adequate up-titration of BB, with particular focus on reducing the treatment gap in women.

Incidence of sustained ventricular tachyarrhythmias in patients with non-ischemic cardiomyopathy in a multicenter multinational WCD cohort

Abstract Background Defibrillator use in patients with non-ischemic cardiomyopathy (NICM) and HFrEF remains controversial after the DANISH study. The new ESC guidelines recommend individualized risk stratification in these patients. The wearable cardioverter-defibrillator (WCD) seems to be appropriate to both protect and screen patients with HFrEF at risk for sudden cardiac death (SCD). Puropose: To evaluate the rate of ventricular tachyarrhythmias (VT/VF) in NICM vs. ICM patients receiving a WCD for temporary SCD protection. Methods 1157 patients were included in a multicenter registry from eight European centers. Among these patients, 602 patients received a WCD due to ischemic cardiomyopathy (ICM) and 555 patients for non-ischemic cardiomyopathy (NICM). Incidence of VT/VF and/or appropriate WCD shock discharge during WCD use were evaluated. The mean follow-up (FU) time of the whole cohort was 620.2±607.8 days. Results NICM patients were younger (mean 56.5±14.8a vs 63.9±11.6a; p&amp;lt;0.001) and less often male (75% vs. 87.2%; p&amp;lt;0.001) compared to ICM patients. Heart failure medication at hospital discharge did not differ between the two groups except for a higher prescription rate of aldosterone-antagonists in NICM compared to ICM patients (73.8% vs. 66.7%; p=0.02). The index left ventricular ejection fraction (LVEF) was significantly lower in NICM compared to ICM patients (mean 26.1±9.1% versus 29.5±9.2%; p&amp;lt;0.001). A larger extent of LVEF recovery was detected in NICM patients compared to ICM patients up to the end of WCD use (mean LVEF post WCD: 45.7±35.4% vs. 40.2±11.8%; p=0.02). Average daily WCD wear-time was significantly lower in NICM patients compared to ICM patients (mean 20.7±4.9h vs. 21.6±3.7h; p=0.01). NICM patients had a significantly lower incidence of sustained ventricular tachyarrhythmia (VT/VF) compared to ICM patients (3.4% vs. 6.6%; p=0.02). Consistently, rate of appropriate WCD shock was significantly lower in NICM vs. ICM patients (0.7% vs. 3.7%; p&amp;lt; 0.001), as was rate of re-hospitalization (30.2% vs. 46.1%; p&amp;lt;0.001). Both groups showed a similar mortality rate during FU. Conclusions Patients at risk for SCD with NICM showed a more pronounced LVEF recovery, significantly lower incidence of VT/VF with concomitant shocks and hospitalization, while overall mortality was unchanged compared to ICM patients. These results indicate that WCD use might facilitate individual SCD risk stratification in NICM patients.

P262 PREDICTORS OF ICD IMPLANTATION: THE ROLE OF THE WEARABLE CARDIOVERTER DEFIBRILLATOR

Abstract Background Previous studies established a role for the wearable cardioverter defibrillator (WCD) In patients with transient risk of sudden cardiac death ( SCD) . In clinical trials, nearly 40% of patients received implantable cardioverter–defibrillator (ICD) implantation at the end of WCD use. It’ unknown if WCD can be usefull in final ICD implantation indication. Objectives We aimed to describe the clinical predictors of ICD implantation rate at the end of WCD use in a real–world single center experience. Methods and results Between August 2017 and June 2022, 60 consecutive patients receiving a WCD at Piacenza Hospitals were retrospectively included in this analysis: : mean age 66.9±11.9 years, 56.6% with ischaemic cardiomyopathy, 38.3% with dilated cardiomyopathy, 5% after implantable cardioverter–defibrillator explant. A total of 34 participants (56.6%) received implantable cardioverter–defibrillator (ICD) implantation at the end of WCD use. We evaluated clinical features related to ICD implantation rate with Chi Square test and Student’s t test. Female sex was related with no ICD implantation ( ICD 5,9% vs no ICD 23,1%, p= 0,03), whilst Low ejection fraction at beginning of evaluation was related with ICD implantation ( ICD 27.1±9.3 vs no ICD 33.1±11.9, p=0,03). Although in our population there weren’t shock of WCD, the strongest clinical predictor was arrhythmic event recordered at WCD monitoring both non sustained ventricular tachicardia, sustained ventricular tachicardia and supraventricular tachicardia ( ICD 20 vs no ICD 0, p &amp;lt; 0,01). Age ( ICD 66.6±11.9 vs NO ICD 67.4±11.9, p=0,7) and etiology of cardiopathy both ischemic and non ischemic ( ICD 52% vs no ICD 53,8%, P=0.5) were not factors associated with ICD implantation. Conclusion In our study the rate of ICD implantation after wearing time of WCD is consistent but slightly major to European registries. Arrhythmic Event recordered at WCD monitoring is related with ICD implantation, so WCD, when it is used, may be a further help in final ICD implantation.

P265 REAL–WORLD SINGLE CENTER EXPERIENCE WITH THE WEARABLE CARDIOVERTER DEFIBRILLATOR: SEX DIFFERENCES IN RISK STRATIFICATION FOR SUDDEN CARDIAC DEATH

Abstract Background Previous studies established a role for the wearable cardioverter defibrillator (WCD) in patients with transient risk os sudden cardiac death ( SCD) . The WEARIT–II Registry highlighted an higher burden of ventricular and atrial arrhythmic events in women than in men, in spite of a similar ICD implantation rates. Objectives We aimed to describe the sex differences in WCD use and compliance. Moreover we reviewed the rate of cardiac events detected with WCD and the rate of ICD implantation in women in a real–world single center experience. Methods and results Between August 2017 and June 2022, 60 consecutive patients receiving a WCD at Piacenza Hospitals were retrospectively included in this analysis: mean age 66.9±11.9 years, 56.6% with ischaemic cardiomyopathy, 38.3% with dilated cardiomyopathy, 5% after implantable cardioverter–defibrillator explant. 8 patients were women (13.3%). Women and men presented similar clinical characteristics. Median WCD usage period and median daily wear time were not different between women and men (49.6±25.3 vs 51.8±32.8 days, 23.6±0.3 vs 23.1±1.7 hours, respectively). No ventricular fibrillation was detected in the monitoring period. Non–sustained ventricular tachycardia and atrial arrhythmias were similar between women and men. However, ICD implantation rate at the end of WCD use was significantly lower in women than and men (25% vs 61.5%; p&amp;lt; 0.01). Conclusions In this real word analysis WCD was underused in women despite a nice compliance. A similar burden of ventricular and atrial arrhythmic events were detected, with a lower ICD implantation rate at the end of WCD use in women than in men.

P10 REAL–WORLD SINGLE CENTER EXPERIENCE WITH THE WEARABLE CARDIOVERTER DEFIBRILLATOR: SEX DIFFERENCES IN RISK STRATIFICATION FOR SUDDEN CARDIAC DEATH

Abstract Background Previous studies established a role for the wearable cardioverter defibrillator (WCD) in patients with transient risk os sudden cardiac death (SCD). The WEARIT–II Registry highlighted an higher burden of ventricular and atrial arrhythmic events in women than in men, in spite of a similar ICD implantation rates. Objectives We aimed to describe the sex differences in WCD use and compliance. Moreover we reviewed the rate of cardiac events detected with WCD and the rate of ICD implantation in women in a real–world single center experience. Methods and results Between August 2017 and June 2022, 60 consecutive patients receiving a WCD at Piacenza Hospitals were retrospectively included in this analysis: mean age 66.9±11.9 years, 56.6% with ischaemic cardiomyopathy, 38.3% with dilated cardiomyopathy, 5% after implantable cardioverter–defibrillator explant. 8 patients were women (13.3%). Women and men presented similar clinical characteristics. Median WCD usage period and median daily wear time were not different between women and men (49.6±25.3 vs 51.8±32.8 days, 23.6±0.3 vs 23.1±1.7 hours, respectively). No ventricular fibrillation was detected in the monitoring period. Non–sustained ventricular tachycardia and atrial arrhythmias were similar between women and men. However, ICD implantation rate at the end of WCD use was significantly lower in women than and men (25% vs 61.5%; p&amp;lt; 0.01). Conclusions In this real word analysis WCD was underused in women despite a nice compliance. A similar burden of ventricular and atrial arrhythmic events were detected, with a lower ICD implantation rate at the end of WCD use in women than in men.

Wearable cardioverter defibrillator after cardiac surgery: Analysis of real-life data from patients at transient risk of sudden cardiac death.

Especially in the first 3months after cardiac surgery, patients are at transient risk of sudden cardiac death (SCD). To close the gap between hospital discharge and the final implantable cardioverter-defibrillator (ICD) decision, guidelines recommend temporarily using a wearable cardioverter-defibrillator (WCD) to protect these patients from SCD. We investigated real-life data on the safety, effectiveness, and compliance of the WCD in this population. Data for analysis were collected via the Zoll Patient Management Network (ZPM) from patients who underwent cardiac surgery and who were discharged with a WCD between 2018 and 2021 at the Cardiac Surgery Center of the University of Erlangen in Germany. The majority of the 55 patients were male (90.9%) and underwent a coronary artery bypass graft (80.0%). The number of patients with left ventricular ejection fraction (LVEF) >35% increased from 9.1% at the beginning of WCD use to 58.2% at the end of WCD use. Six ventricular tachycardia (VT) episodes occurred in four patients. The WCD appropriately defibrillated two patients with VT episodes. There were no inadequate shocks and no fatalities during the observation time. WCD wearing compliance was high, with a median wear time of 23.3h/day. This retrospective analysis in a single cardiac surgery center confirms prior data on the safety and effectiveness of the WCD in patients in post-surgery care in a real-life setting. The WCD successfully protected patients from SCD during life-threatening VT episodes. WCD wearing compliance was high.

Abstract 13825: Clinical and Echocardiographic Outcomes Associated With Early Initiation of Beta Blockers Use Among Patients With Recently Diagnosed Non-Ischemic Cardiomyopathy Treated With a Wearable Cardioverter Defibrillator

Introduction: Beta-blocker (BB) therapy was shown to improve clinical outcomes among heart failure patients with reduced ejection fraction. However, there are limited data on the efficacy of BB use among patients with recently diagnosed non-ischemic heart cardiomyopathy (NICM) who are treated with the wearable cardioverter defibrillator (WCD) until a decision on the need for an ICD is made. Aim: Determine if BB use is associated with improved outcomes in patients with NICM treated with the WCD. Methods: The study population comprised 1195 patients with recently diagnosed NICM enrolled in the prospective WEARIT-II Registry. Clinical data, arrhythmia events, ICD implantation, and improvement in left ventricular ejection fraction (LVEF) were captured. Multivariate logistic regression was used to estimate the odds ratio (OR) of LVEF improvement to &gt;35% by BB usage. The risk of death at 1-year by BB use was assessed using a multivariate cox-proportional hazards modeling. Results: Patients treated with BBs at baseline were more likely to experience an improvement in LVEF to &gt;35% that patients who did not receive treatment with BB (43% vs 29%, respectively; adjusted OR=1.67 95% CI [1.15-2.41] p=0.007; Figure: panel A and were less likely to receive an ICD at the end of the WCD use (37% vs 47%; adjusted OR=0.64 95% CI [0.46-0.90] p=0.024; Figure: panel B). At 12 months of follow-up the probability of death was significantly lower among patients who received BB therapy during WCD use vs. those who did not.,(p=0.007 Figure: panel C), corresponding to a significant 59% lower risk of death at one year associated with early BB use (adjusted HR=0.41 95% CI [0.21-0.80] p&lt;0.01). Conclusions: Among patients newly diagnosed NICM who are treated with a WCD until a decision on the need for an ICD is made, early initiation of BB is independently associated with a greater likelihood of improvement in EF, a lower probability of needing an ICD at end of WCD use, and a lower risk of death at 1-year.

High Resting Heart Rates Are Associated with Early Posthospitalization Mortality in Low Ejection Fraction Patients.

Guideline-directed medical therapy (GDMT) is crucial in reducing mortality in patients with heart failure with heart rate lowering by a beta blocker (BB) being an important therapeutic concept. We aimed to assess the usefulness of a wearable cardioverter/defibrillator (WCD) to provide detailed information about heart rate for managing patients with reduced left ventricular ejection fraction (LVEF) and symptoms of heart failure and to correlate mortality with the mean heart rate. A total of 4509 consecutive patients (mean age: 59 + 13 years, 88% male) were analyzed retrospectively. All patients had reduced LVEF and were prescribed a WCD for protection from sudden cardiac death (SCD) during GDMT uptitration awaiting LVEF recovery. The device continuously measured nighttime and daytime HR at the beginning and end of WCD use. Patients who died during wear time had significantly higher HRs compared with survivors: daytime beginning of use (BOU), 80 ± 15 bpm vs. 76 ± 13, p < 0.01; nighttime BOU, 76 ± 14 vs. 69 ± 13, p < 0.0001; daytime end of use (EOU), 84 ± 20 vs. 73 ± 13, p < 0.0001; nighttime EOU, 80 ± 20 vs. 65 ± 12, p < 0.0001). In conclusion, HR monitoring with a WCD yields important prognostic information and may assist in optimal usage of BB in patients with low LVEF.

Sex differences in arrhythmic burden with the wearable cardioverter-defibrillator

Data on the arrhythmic burden of women at risk for sudden cardiac death are limited, especially in patients using the wearable cardioverter-defibrillator (WCD). We aimed to characterize WCD compliance, atrial and ventricular arrhythmic burden, and WCD outcomes by sex in patients enrolled in the Prospective Registry of Patients Using the Wearable Cardioverter Defibrillator (WEARIT-II U.S. Registry). In the WEARIT-II Registry, we stratified 2000 patients by sex into women (n = 598) and men (n = 1402). WCD wear time, ventricular and atrial arrhythmic events during WCD use, and implantable cardioverter-defibrillator (ICD) implantation rates at the end of WCD use were evaluated. The mean WCD wear time was similar in women and men (94 days vs 90 days; P = .145), with longer daily use in women (21.4 h/d vs 20.7 h/d; P = .001). Burden of ventricular tachycardia or ventricular fibrillation was higher in women, with 30 events per 100 patient-years compared with 18 events per 100 patient-years in men (P = .017), with similar findings for treated and non-treated ventricular tachycardia/ventricular fibrillation. Recurrent atrial arrhythmias/sustained ventricular tachycardia was also more frequent in women than in men (167 events per 100 patient-years vs 73 events per 100 patient-years; P=.042). However, ICD implantation rate at the end of WCD use was similar in both women and men (41% vs 39%; P = .448). In the WEARIT-II Registry, we have shown a higher burden of ventricular and atrial arrhythmic events in women than in men. ICD implantation rates at the end of WCD use were similar. Our findings warrant monitoring women at risk for sudden cardiac death who have a high burden of atrial and ventricular arrhythmias while using the WCD.

The impact of wearable cardioverter-defibrillator use on long-term decision for implantation of a cardioverter-defibrillator in a semirural acute care hospital

PurposeLarge-scale multi-center studies have reported on efficacy of the wearable cardioverter-defibrillator (WCD). However, outcomes focused on WCD patients treated at community-based acute care centers are lacking.MethodsPatients with cardiomyopathy were included when left ventricular ejection fraction (LVEF) at baseline was ≤ 35%. There were 120 patients meeting the criteria who also had LVEF measured at baseline and after 90 days of WCD use.ResultsAfter 90 days of WCD use, there were 44 (37%) patients in whom LVEF improved to > 35%. Comparison of patients, by whether LVEF improved or not, indicated that median days of WCD wear and hours of daily use were similar as well as characteristics, such as gender, age, and starting LVEF; and diagnoses leading to WCD prescription were similar between groups as were symptom-based prescription of medications. At the end of WCD use, improved LVEF > 35% correlated with fewer implantable cardioverter-defibrillator (ICD) implants. There were 4 (3%) episodes of new atrial fibrillation detected during WCD use. The WCD appropriately delivered a shock to 3 (2.5%) patients with VT/VF being terminated by the first shock. All shocked patients survived for at least 24 h post-shock.ConclusionsDuring WCD use, ischemic and non-ischemic cardiomyopathy patients manifest improved LVEF by 90 days. Long-term care decisions, such as implantation of an ICD, were influenced by LVEF improvement and occurrence of spontaneous VT/VF. The WCD protected patients from sudden cardiac death (SCD) until patient response to guideline-directed medical therapy could be determined.

P3517Failure to achieve adequate heart rate control in women during therapy optimization

Abstract Background Previous studies highlighted the importance of adequate heart rate control in heart failure patients, and suggested under-treatment with beta-blockers especially in women. However, data on women achieving effective heart rate control during beta-blocker therapy optimization are lacking. Methods The wearable cardioverter defibrillator (WCD) allows continuous monitoring of heart rate (HR) trends during WCD use. In the current study, we assessed resting HR trends (nighttime: midnight-7am) in women, both at the beginning of WCD use and at the end of WCD use to assess the adequacy of beta-blockade following a typical 3 months of therapy optimization with beta-blockers. An adequate heart rate control was defined as having a nighttime HR &lt;70 bpm at the end of the 3 months. Results There were a total of 21,453 women with at least 30 days of WCD use (&gt;140 hours WCD use on the first and last week). The mean age was 67 years (IQR 58–75). The mean nighttime heart rate was 72 bpm (IQR 65–81) at the beginning of WCD use, that decreased to 68 bpm (IQR 61–76) at the end of WCD use with therapy optimization. Women had an insufficient heart rate control with resting heart rate ≥70 bpm in 59% at the beginning of WCD use that decreased to 44% at the end of WCD use, but still remained surprisingly high. Interestingly, there were 21% of the women starting with HR ≥70 bpm at the beginning of use (BOU) who achieved adequate heart rate control by the end of use (EOU). Interestingly, 6% of women with adequate heart rate control at the start of therapy optimization ended up having higher heart rates &gt;70 bpm at the end of the therapy optimization time period (Figure). Figure 1 Conclusions A significant proportion of women with heart failure and low ejection fraction do not reach an adequate heart rate control during the time of beta blocker initiation/titration. The wearble cardioverter defibrillator is a monitoring device that has been demonstrated in this study to appropriately identify patients with inadequate heart rate control at the end of the therapy optimization period. The WCD could be utilized to improve management of beta-blocker therapy in women and improve the achievement of adequate heart rate control in women.

2403Experience with the wearable cardioverter-defibrillator by disease etiology: results from the wearit-II registry

Abstract Background The use of the wearable cardioverter-defibrillator (WCD) in patients with non-ischemic cardiomyopathy has been less characterized. Objective We aimed to characterize WCD use and outcomes for patients with ischemic or non-ischemic cardiomyopathy, enrolled in the WEARIT-II Registry. Methods In WEARIT-II, we stratified 1,732 patients into ischemic (n=805) and non-ischemic etiology (n=927). WCD wear time, arrhythmia events during WCD use, and implantable cardioverter-defibrillator (ICD) implantation rates, or ejection fraction (EF) improvement at the end of WCD were evaluated for etiology subgroups. Results The WCD median wear time was higher in patients with non-ischemic cardiomyopathy (93 vs. 87 days, p=0.003), however daily use was similar (22.4 vs. 22.6 hours, p=0.07). There were 24 ischemic patients (3%) with sustained VT/VF events compared to 10 patients (1%) with non-ischemic cardiomyopathy (p=0.013). About 2/3 of these events were treated with WCD shock in ischemic patients, half of them in the non-ischemic group (1.9% vs. 0.4%). Atrial arrhythmias were frequent in both groups (3.1% vs. 3.1%, p=0.06). At the end of WCD use, 36% of the non-ischemic patients were implanted with an ICD compared to 42% in ischemic (p=0.01), likely due to the lower rate of sustained ventricular arrhythmias (Figure). Figure 1 Conclusions In WEARIT-II, patients with non-ischemic cardiomyopathy had longer WCD use than ischemic patients with good compliance. The rate of sustained ventricular arrhythmia events was lower in non-ischemic patients avoiding the need for an ICD implantation in more patients compared to ischemic, following a time period of risk stratification. Acknowledgement/Funding WEARIT-II was funded by an unrestricted research grant from ZOLL Inc.

Failure to Achieve Adequate Heart Rate Control in Women during Therapy Optimization

Background Previous studies highlighted the importance of adequate heart rate control in heart failure patients, and suggested under-treatment with beta-blockers especially in women. However, data on women achieving effective heart rate control during beta-blocker therapy optimization are lacking. Methods The wearable cardioverter defibrillator (WCD) allows continuous monitoring of heart rate (HR) trends during WCD use. In the current study, we assessed resting HR trends (nighttime: midnight-7am) in women, both at the beginning of WCD use and at the end of WCD use to assess the adequacy of beta-blockade following a typical 3 months of therapy optimization with beta-blockers. An adequate heart rate control was defined as having a nighttime HR Results There were a total of 21,453 women with at least 30 days of WCD use (>140 hours WCD use on the first and last week). The mean age was 67 years (IQR 58-75). The mean nighttime heart rate was 72 bpm (IQR 65-81) at the beginning of WCD use that decreased to 68 bpm (IQR 61-76) at the end of WCD use with therapy optimization. Women had an insufficient heart rate control with resting heart rate ≥ 70 bpm in 59% at the beginning of WCD use that decreased to 44% at the end of WCD use, but still remained surprisingly high. Interestingly, there were 21% of the women starting with HR ≥ 70 bpm at the beginning of use (BOU) who achieved adequate heart rate control by the end of use (EOU). Interestingly, 6% of women with adequate heart rate control at the start of therapy optimization ended up having higher heart rates >70 bpm at the end of the therapy optimization time period (Figure). Conclusions A significant proportion of women with heart failure and low ejection fraction do not reach an adequate heart rate control during the time of beta blocker initiation/titration. The wearble cardioverter defibrillator is a monitoring device that has been demonstrated in this study to appropriately identify patients with inadequate heart rate control at the end of the therapy optimization period. The WCD could be utilized to improve management of beta-blocker therapy in women and improve the achievement of adequate heart rate control in women.

Achieving Guideline-Directed Heart Rate ControlEarly Posthospitalization

Guidelines for the treatment of heart failure (HF) recommend the titration of β blockers (BB) to a target dosage shown to be effective in clinical trials. The benefit of BBs is associated with heart rate (HR) control, with a target resting HR <70 bpm which in clinical trials have been associated with improved clinical outcomes. The primary purpose of this study was to gauge the ability to achieve guideline-directed medical therapy HR control in the early posthospitalization period for HF patients with the wearable cardioverter defibrillator (WCD), assessing whether the WCD could be used to evaluate HR both at rest and during activity to determine if targets were being met and to adequately direct clinical decision making. The WCD platform allows continuous recording of HR. To assess the guideline-directed therapy goals for reduction of resting HR, HR was evaluated both at rest (nighttime: midnight-7 a.m.; daytime: 7 a.m. midnight), and during activity of daily living. HR data during activity of daily living (ADL) and rest were collected from patients with HF that wore the WCD for ≥5 weeks (n = 1,353) between 2015 and 2017. First, 643,891 activity episodes from 1,353 patients were analyzed. Daytime and nighttime resting HRs significantly dropped from beginning to end of WCD use (day: 72.5 bpm vs 69.0 bpm, p <0.0001; night: 68.1 vs 64.3, p <0.0001). However, 43% of patients still had an average daytime resting HR ≥70 bpm during the last week of WCD use. When comparing a patient's peak activity HR during the first week of WCD use to the last week, there was no difference (93.6 bpm vs 94.1 bpm, p = 0.23). During ADL, 31% of patients had a HR ≥100 bpm, 14% of patients had a HR ≥110 bpm, and 6% had a HR ≥120 bpm. In conclusion, months after hospital discharge, 43% of patients did not meet guideline-directed resting target HR control, indicating they may not have been effectively managed with BB. HR during ADL may have also been higher than preferred. Remote HR monitoring may help physicians to adequately titrate guideline-directed medical therapy, thus improving clinical outcomes in HF patients.

Experience with the wearable cardioverter-defibrillator in older patients: Results from the Prospective Registry of Patients Using the Wearable Cardioverter-Defibrillator

Use of the wearable cardioverter-defibrillator (WCD) in older patients has not been described previously. The purpose of this study was to assess WCD wear time, risk of arrhythmic events during WCD use, and implantable cardioverter-defibrillator (ICD) implantation rates after the end of WCD use in patients with age ≥65 years vs <65 years. We stratified 1732 patients with ischemic and nonischemic cardiomyopathy from the Prospective Registry of Patients Using the Wearable Defibrillator Registry into 2 subgroups by age: those with age ≥65 years and those with age <65 years. Wear time, arrhythmic events, and end-of-use decisions, specifically ICD implantation or improvement in ejection fraction, were evaluated for each age group. There were 722 patients with age ≥65 years (41.7%) and 1010 patients with age <65 years (58.3%). Daily WCD wear time was longer in the older population (median 22.8 h/d (IQR 21.5 - 23.2) vs 22.3 h/d (IQR 19.5 - 23.0); P < .001). Patients with age ≥65 years experienced higher eventrates, per 100 patient-years, for any sustained ventricular tachycardia/ventricular fibrillation (31.95 vs 9.82; P = .027) and ventricular tachycardia/ventricular fibrillation treated with WCD shock (6.92 vs 2.37; P = .034), particularly with ischemic cardiomyopathy. Younger patients experienced a trend toward a higher event rate for atrial arrhythmias with nonischemic cardiomyopathy (150.07 vs 74.86; P = .055). At the end of WCD use, ICD implantation was more frequent in older patients (41.8% vs 36.5%; P=.034). Older patients had good compliance with the WCD, presented with more frequent ventricular arrhythmias, and were more likely to receive an ICD at the end of WCD use. The WCD may play a role in risk stratification of the older population.

Use of the wearable cardioverter defibrillator in high-risk cardiac patients: data from the Prospective Registry of Patients Using the Wearable Cardioverter Defibrillator (WEARIT-II Registry).

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.

Wearable defibrillator use in heart failure (WIF): results of a prospective registry

BackgroundHeart 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.MethodsTen 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).ResultsOut 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.ConclusionsIn conclusion, 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.