An observational study in Sudden Cardiac Death, Sudden Cardiac Arrest and Heart Failure, sponsored by Zoll Medical Corporation. Completed at 67 sites in 4 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-03-24.
Sponsored by Zoll Medical Corporation · Observational
This study is designed as a multi-center prospective observational study of newly diagnosed Heart Failure (HF) patients to test the hypothesis that additional Ejection Fraction (EF) recovery occurs between 90 and 180 days as Guideline Directed Medical Therapy (GDMT) is achieved. Although the study doesn't start until day 90, all eligible, consenting patients will be entered into a registry at the start of wearable cardioverter defibrillator (WCD) use. The pre-study registry will allow us to collect early (90 day) outcomes and data in those patients who are likely to be eligible for the study at day 90, or are eligible, but refuse the study at day 90.
This study will be conducted at thirty to sixty sites, initially in US and Europe. It will be used to observe the rate of recovery of ventricular function (EF>35%) between 90 and 180 days in newly diagnosed HF patients who were prescribed the WCD ≤ 10 days post-discharge after hospitalization for a primary reason of new onset HF (≤30 days since first HF hospitalization), with ischemic or non-ischemic cardiomyopathy, and have already used a WCD for 90 ± 14 days. For the first 90 days of WCD use, patients will be enrolled in a pre-study registry. The FDA-approved WCD will be prescribed for up to 6 months of use after hospital discharge, with the option for longer use under physician discretion. Approximately 870 subjects will enroll into the pre-study registry and 750 subjects into the study.
5,701 studies on the registry are indexed under Heart Failure; 1,220 are open to participants now.
This study's enrollment of 602 is above the median of 200 across 1,679 observational studies indexed under Heart Failure.
Browse Heart Failure studies →Zoll Medical Corporation is the lead sponsor of 34 studies on the registry; 5 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Patients (≥18 years old) who used a WCD for 90 days after hospitalization for a primary reason of new onset HF with ischemic or nonischemic cardiomyopathy.
Inclusion Criteria:
Phase 1 (Registry phase)
Phase 2 (Study phase)
Exclusion Criteria (both phases):
Exclusion criteria (Phase 2)
Patients improved to LVEF \>35% within the first 90 days following GDMT. These patients are expected to end WCD use and not receive an implantable cardioverter defibrillator (ICD) according to current guidelines.
Patients improved LVEF from start of WCD use (a positive change of at least 5% in LVEF) or have borderline LVEF of 30-35% at day 90. These patients were expected, but not required to continue to use the WCD for an additional 90 days.
Device: Wearable Cardioverter Defibrillator
Patients show no change, worsening of LVEF or LVEF \<30%. Those on GDMT are expected to be evaluated for an ICD. Those not yet on GDMT were expected, but not required, to continue the WCD for an additional 90 days.
Device: Wearable Cardioverter Defibrillator
LifeVest is the brand of Wearable Cardioverter Defibrillator used in this study.
Also known as: LifeVest
Percentage of Patients With LVEF Recovery at Day 90 and 180
The percentage of patients reaching the goal of LVEF\>35% will be compared at 90 days and 180 days. Echocardiographic assessment of LVEF was used.
Time frame: 180 days
Percentage of Study Subjects Reaching Target Doses of Guideline Directed Medical Therapy (GDMT)
Descriptive statistics will be used to assess the percentage of study subjects reaching target doses of GDMT at 90 and 180 days. All eligible study subjects with LVEF data at all three timepoints were used for this analysis.
Time frame: 180 days
All Subjects With Sustained Ventricular Tachycardia (VT)/Ventricular Fibrillation (VF) Arrhythmias During WCD Use
Observe the percentage of patients having sustained VT/VF arrhythmias during WCD use. As this was a secondary outcome to describe events during all WCD use, all eligible registry subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
Time frame: 360 days
All Sustained Ventricular Tachycardia (VT)/Ventricular Fibrillation (VF) Arrhythmias Events During WCD Use
Observe the occurrence of all sustained VT/VF arrhythmias during WCD use by event. As this was a secondary outcome to describe events during all WCD use, all eligible registry subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
Time frame: 360 days
Percentage of All Patients Having Other Arrhythmias
Observe the percentage of patients having other arrhythmias during WCD use, such as asystole and supra-ventricular arrhythmias that are recorded by the device. As this was a secondary outcome to describe events during all WCD use, all eligible registry subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
Time frame: 180 days
Efficacy in Treating Ventricular Arrhythmias
Observe the effectiveness of the wearable cardioverter defibrillator worn by this population in treating ventricular arrhythmias. As this was a secondary outcome to describe events during all WCD use, all eligible registry subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
Time frame: 180 days
Mortality Analysis
Evaluate the effect of wearable defibrillators on 180, 270, and 360-day mortality following discharge in HF patients. Cumulative assessment of survival will be made at these time points for those entered into the study (e.g. up to 180, 270, 360 days, or \>360 days (up to 14 months)). A mortality review will be conducted by independent adjudicators to group all deaths as cardiac or non-cardiac, and sudden or non-sudden. All eligible study subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes. Data collected on deaths after the prespecified final timepoint (n=3) will be labeled \>360 days (up to 14 months). 1 subject completed the study immediately prior to the reported death, hence the different number from the participant flow.
Time frame: 0 to180, 0 to 270, and 0 to 360 days, or >360 days (up to 14 months)
Healthcare utilization_type
Healthcare utilization (emergency room visits, hospitalizations, doctor visits etc.) on all patients during the period of the study. All eligible study subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
Time frame: 360 days
Healthcare utilization_length of Use
Length of stay for any hospitalization, observation, skilled nursing facility stays. All eligible study subjects reporting one of these stays were used for this analysis, and grouped by type of stay. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
Time frame: 360 days
Complications From Extended Use
The safety objectives will be to compare complications from extended use of the WCD with those of the ICD during the study phase timeframe. All eligible study subjects were used for this safety analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
Time frame: 360 days
| Milestone | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) |
|---|---|---|---|---|
| Started | 279 | 214 | 90 | 19 |
| Completed | 243 | 183 | 77 | 9 |
| Not completed | 36 | 31 | 13 | 10 |
| Withdrew: Death | 5 | 4 | 5 | 1 |
| Withdrew: Lost to follow-up | 23 | 17 | 4 | 2 |
| Withdrew: Withdrawal by subject | 6 | 6 | 2 | 2 |
| Withdrew: Other/unknown | 2 | 4 | 2 | 1 |
| Withdrew: Protocol violation | 0 | 0 | 0 | 4 |
The percentage of patients reaching the goal of LVEF\>35% will be compared at 90 days and 180 days. Echocardiographic assessment of LVEF was used.
| Participants | Early Recovery | Improvement | Non-improvement |
|---|---|---|---|
| Day 90 LVEF — Day 90 LVEF >35% | 222 | 0 | 0 |
| Day 90 LVEF — Day 90 LVEF <=35% | 0 | 186 | 79 |
| Day 180 LVEF — Day 90 LVEF >35% | 208 | 97 | 25 |
| Day 180 LVEF — Day 90 LVEF <=35% | 14 | 89 | 54 |
Descriptive statistics will be used to assess the percentage of study subjects reaching target doses of GDMT at 90 and 180 days. All eligible study subjects with LVEF data at all three timepoints were used for this analysis.
| Participants | Early Recovery | Improvement | Non-improvement |
|---|---|---|---|
| Reached target dose beta-blocker at Day 90 — Target dose reached | 57 | 36 | 16 |
| Reached target dose beta-blocker at Day 90 — Target dose not reached | 164 | 149 | 63 |
| Reached target dose beta-blocker at Day 90 — Dose not available | 1 | 1 | 0 |
| Reached target dose RAS antagonist at Day 90 — Target dose reached | 86 | 59 | 16 |
| Reached target dose RAS antagonist at Day 90 — Target dose not reached | 136 | 125 | 63 |
| Reached target dose RAS antagonist at Day 90 — Dose not available | 0 | 2 | 0 |
| Reached target dose mineralocorticoid receptor antagonist at Day 90 — Target dose reached | 114 | 77 | 30 |
| Reached target dose mineralocorticoid receptor antagonist at Day 90 — Target dose not reached | 108 | 109 | 49 |
| Reached target dose mineralocorticoid receptor antagonist at Day 90 — Dose not available | 0 | 0 | 0 |
| Reached target dose beta-blocker at Day 180 — Target dose reached | 56 | 47 | 19 |
| Reached target dose beta-blocker at Day 180 — Target dose not reached | 166 | 139 | 60 |
| Reached target dose beta-blocker at Day 180 — Dose not available | 0 | 0 | 0 |
| Reached target dose RAS antagonist at Day 180 — Target dose reached | 92 | 84 | 22 |
| Reached target dose RAS antagonist at Day 180 — Target dose not reached | 130 | 101 | 56 |
| Reached target dose RAS antagonist at Day 180 — Dose not available | 0 | 1 | 1 |
| Reached target dose mineralocorticoid receptor antagonist at Day 180 — Target dose reached | 103 | 84 | 30 |
| Reached target dose mineralocorticoid receptor antagonist at Day 180 — Target dose not reached | 119 | 102 | 49 |
| Reached target dose mineralocorticoid receptor antagonist at Day 180 — Dose not available | 0 | 0 | 0 |
Observe the percentage of patients having sustained VT/VF arrhythmias during WCD use. As this was a secondary outcome to describe events during all WCD use, all eligible registry subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
| Participants | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) |
|---|---|---|---|---|
| All Subjects With Sustained Ventricular Tachycardia (VT)/Ventricular Fibrillation (VF) Arrhythmias During WCD Use | 4 | 1 | 0 | 0 |
Observe the occurrence of all sustained VT/VF arrhythmias during WCD use by event. As this was a secondary outcome to describe events during all WCD use, all eligible registry subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
| events | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) |
|---|---|---|---|---|
| All Sustained Ventricular Tachycardia (VT)/Ventricular Fibrillation (VF) Arrhythmias Events During WCD Use | 5 | 1 | 0 | 0 |
Observe the percentage of patients having other arrhythmias during WCD use, such as asystole and supra-ventricular arrhythmias that are recorded by the device. As this was a secondary outcome to describe events during all WCD use, all eligible registry subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
| Participants | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) |
|---|---|---|---|---|
| Asystole | 0 | 1 | 0 | 0 |
| Non-sustained ventricular tachycardia | 0 | 1 | 2 | 0 |
| Supraventricular tachycardia | 13 | 20 | 4 | 1 |
| Sinus tachycardia | 1 | 0 | 0 | 0 |
Observe the effectiveness of the wearable cardioverter defibrillator worn by this population in treating ventricular arrhythmias. As this was a secondary outcome to describe events during all WCD use, all eligible registry subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
| Participants | All Registry Subjects With Appropriate Shock for VT/VF |
|---|---|
| Successfully cardioverted by the wearable cardioverter defibrillator | 7 |
| Not successfully cardioverted by the wearable cardioverter defibrillator | 0 |
Evaluate the effect of wearable defibrillators on 180, 270, and 360-day mortality following discharge in HF patients. Cumulative assessment of survival will be made at these time points for those entered into the study (e.g. up to 180, 270, 360 days, or \>360 days (up to 14 months)). A mortality review will be conducted by independent adjudicators to group all deaths as cardiac or non-cardiac, and sudden or non-sudden. All eligible study subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes. Data collected on deaths after the prespecified final timepoint (n=3) will be labeled \>360 days (up to 14 months). 1 subject completed the study immediately prior to the reported death, hence the different number from the participant flow.
| Participants | All Study Phase Subjects Who Died |
|---|---|
| 180 Day cumulative mortality — Cardiovascular death_Sudden | 2 |
| 180 Day cumulative mortality — Cardiovascular death_Non sudden | 1 |
| 180 Day cumulative mortality — Non-cardiovascular death_Sudden | 1 |
| 180 Day cumulative mortality — Non-cardiovascular death_Non Sudden | 0 |
| 180 Day cumulative mortality — Unknown death_Sudden | 1 |
| 180 Day cumulative mortality — Unknown death_Non Sudden | 0 |
| 270 Day cumulative mortality — Cardiovascular death_Sudden | 2 |
| 270 Day cumulative mortality — Cardiovascular death_Non sudden | 2 |
| 270 Day cumulative mortality — Non-cardiovascular death_Sudden | 1 |
| 270 Day cumulative mortality — Non-cardiovascular death_Non Sudden | 3 |
| 270 Day cumulative mortality — Unknown death_Sudden | 1 |
| 270 Day cumulative mortality — Unknown death_Non Sudden | 0 |
| 360 Day cumulative mortality — Cardiovascular death_Sudden | 3 |
| 360 Day cumulative mortality — Cardiovascular death_Non sudden | 2 |
| 360 Day cumulative mortality — Non-cardiovascular death_Sudden | 1 |
| 360 Day cumulative mortality — Non-cardiovascular death_Non Sudden | 6 |
| 360 Day cumulative mortality — Unknown death_Sudden | 1 |
| 360 Day cumulative mortality — Unknown death_Non Sudden | 0 |
| >360 Day cumulative mortality (up to 14 months) — Cardiovascular death_Sudden | 3 |
| >360 Day cumulative mortality (up to 14 months) — Cardiovascular death_Non sudden | 2 |
| >360 Day cumulative mortality (up to 14 months) — Non-cardiovascular death_Sudden | 1 |
| >360 Day cumulative mortality (up to 14 months) — Non-cardiovascular death_Non Sudden | 9 |
| >360 Day cumulative mortality (up to 14 months) — Unknown death_Sudden | 1 |
| >360 Day cumulative mortality (up to 14 months) — Unknown death_Non Sudden | 0 |
Healthcare utilization (emergency room visits, hospitalizations, doctor visits etc.) on all patients during the period of the study. All eligible study subjects were used for this analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
| Heathcare Utilization Events | All Eligible Study Subjects |
|---|---|
| Doctor visits | 2640 |
| Hospitalizations | 247 |
| Emergency room visits | 125 |
| UrgiCare visits | 21 |
| Skilled nursing facility/rehabilitation | 16 |
| Observational stay | 81 |
Length of stay for any hospitalization, observation, skilled nursing facility stays. All eligible study subjects reporting one of these stays were used for this analysis, and grouped by type of stay. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
| days | Hospital Stays | Observation Stays | Skilled Nursing Facility Stays |
|---|---|---|---|
| Healthcare utilization_length of Use | 3 (0 to 49) | 1 (0 to 15) | 2 (1 to 22) |
The safety objectives will be to compare complications from extended use of the WCD with those of the ICD during the study phase timeframe. All eligible study subjects were used for this safety analysis. Participants were not split into groups for secondary analyses, only for reporting results of left ventricular ejection fraction (LVEF) recovery in the primary outcomes.
| Participants | All Eligible Study Subjects |
|---|---|
| Inappropriate shock from WCD during study phase (extended use >104 days) | 1 |
| Inappropriate shock from ICD during study phase | 0 |
| No reported inappropriate shock during study phase | 597 |
Collected over All-cause mortality was assessed up to 14 months; serious and other (not including serious) adverse events were assessed for up to 1 year.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Early Recovery | 5/279 (1.8%) | 0/279 (0%) | 8/279 (2.9%) |
| Improvement | 4/214 (1.9%) | 1/214 (0.5%) | 14/214 (6.5%) |
| Non-improvement | 6/90 (6.7%) | 0/90 (0%) | 3/90 (3.3%) |
| Unassigned Based on Left Ventricular Ejection Fraction (LVEF) | 1/19 (5.3%) | 0/19 (0%) | 0/19 (0%) |
| Event | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) |
|---|---|---|---|---|
| Asystole with Inappropriate shockCardiac disorders | 0/279 | 1/214 | 0/90 | 0/19 |
| Event | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) |
|---|---|---|---|---|
| Skin irritationSkin and subcutaneous tissue disorders | 7/279 | 12/214 | 2/90 | 0/19 |
| Inappropriate shockProduct Issues | 0/279 | 1/214 | 1/90 | 0/19 |
| DiscomfortProduct Issues | 1/279 | 1/214 | 0/90 | 0/19 |
| FrustrationProduct Issues | 0/279 | 1/214 | 0/90 | 0/19 |
Subjects consented and enrolled into the study phase at Day 90.
| Age, Continuous(years) | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) | Total |
|---|---|---|---|---|---|
| Mean | 59 ± 13 | 57 ± 14 | 60 ± 13 | 58 ± 11 | 59 ± 13 |
| Sex: Female, Male(Participants) | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) | Total |
|---|---|---|---|---|---|
| Female | 88 | 49 | 25 | 2 | 164 |
| Male | 191 | 165 | 65 | 17 | 438 |
| Race/Ethnicity, Customized(Participants) | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) | Total |
|---|---|---|---|---|---|
| Race/Ethnicity — American Indian or Alaskan native | 2 | 1 | 0 | 1 | 4 |
| Race/Ethnicity — Asian | 0 | 2 | 1 | 0 | 3 |
| Race/Ethnicity — Caucasian | 231 | 173 | 65 | 15 | 484 |
| Race/Ethnicity — Hispanic or Latin | 4 | 3 | 5 | 0 | 12 |
| Race/Ethnicity — Black or African American | 31 | 27 | 15 | 2 | 75 |
| Race/Ethnicity — Other | 0 | 0 | 1 | 0 | 1 |
| Race/Ethnicity — No response | 7 | 8 | 3 | 1 | 19 |
| Race/Ethnicity — Multiple races selected | 4 | 0 | 0 | 0 | 4 |
| Region of Enrollment(participants) | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) | Total |
|---|---|---|---|---|---|
| Austria | 10 | 1 | 1 | 4 | 16 |
| United States | 151 | 115 | 57 | 8 | 331 |
| France | 3 | 6 | 2 | 4 | 15 |
| Germany | 115 | 92 | 30 | 3 | 240 |
| Body Mass Index (BMI)(kg/m^2) | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) | Total |
|---|---|---|---|---|---|
| Mean | 30.0 ± 7.4 | 29.0 ± 6.4 | 29.8 ± 7.2 | 28.7 ± 6.2 | 29.6 ± 7.0 |
| Systolic blood pressure(mmHg) | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) | Total |
|---|---|---|---|---|---|
| Mean | 124 ± 22 | 116 ± 19 | 118 ± 15 | 124 ± 20 | 120 ± 20 |
| History of hypertension (HTN)(Participants) | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) | Total |
|---|---|---|---|---|---|
| Count of participants | 196 | 122 | 54 | 14 | 386 |
| History of diabetes(Participants) | Early Recovery | Improvement | Non-improvement | Unassigned Based on Left Ventricular Ejection Fraction (LVEF) | Total |
|---|---|---|---|---|---|
| Count of participants | 69 | 61 | 27 | 7 | 164 |
15 further baseline measures are reported on the registry.
Documents are hosted by the registry — open the source record to download them.
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Zoll Medical Corporation