LifeVest Sven Reek, Aarau Conflict of interest: none
WCD (LifeVest, ZOLL, Pittsburg,PA) Technical aspects Wearable garment with 4 dry ECG electrodes (detection) 3 defibrillation pads External defibrillator with patient interface unit Up to 5 biphasic shocks (150J) ECG monitoring/event recording No pacing
Alarm Sequence 1. Arrhythmia detected, activating vibration alert (continues throughout sequence). 2. Siren alerts begin (continues throughout sequence). 3. Siren alerts get louder. 4. Patient audible prompt: Electrical shock possible. 5. Gel release. 6. Bystander audible prompt: "Do not touch patient. 7. Treatment shock.
VF nsvt * ** ** *
Clinical Experience WEARIT Wearable Cardioverter Defibrillator Investigational Trial - Heart Failure NYHA II-IV, LVEF < 30% BIROAD Bridge to ICD in Patients at Risk of Sudden Arrhythmic Death - complicated MI or CABG
Results WEARIT/BIROAD 285 pts, age 59 y, EF 30%, time of use 3.1 months Time of use according to indication: 3.4 months, 19 h/day (WEARIT); 2.6 months, 21 h/day (BIROAD) 8 VT/VF episodes in 6 pts 6 successful defibrillations (first shock success) 12 pts died (6 non-scd, 5 SCD w/o WCD, 1 SCD while wearing the device) 6 inappropriate shocks Feldmann AM, PACE 2004
US Experience 8/2002-12/2006 Analysis based on ZOLL registry (post market release) Event electrograms reviewed by authors 3569 pts (143 643 patient days) 2723 pts with baseline data Age 59±15 y (12-93 y) Male 74% Chung MK, JACC 2010
Indications Traditional Non-Traditional ICD explantation Postponed implantation with classic indication Congenital anomalies Cardiomyopathy EF.35 Post-MI EF.35 Post-CABG EF.35 Newly diagnosed cardiomyopathy EF.35 Post-MI EF >.35 Chung MK, JACC 2010
Events Mortality: 0.78% in 53 days Survival: 89.5% of all ventricular tachyarrhythmias 73.6% of all events Chung MK, JACC 2010
Events by indication 1.4% 5.2% 0.8% 0.7% 2.9% Chung MK, JACC 2010
Experience in Germany 2000-2008 354 pts (43 centers) Age 57.5 y (29% > 70 y) Male 82% Time of use: 106 days (12 days 7 years) Daily use: 21.3 h/d, (72% 22 h, 85% 20 h) Klein et al, PACE, 2010
Klein et al, PACE, 2010 Indications
Results 27 pts with tachycardias (7.6%) 228 VT/VF, 8 nsvt, 8 SVT, (2 asystole) 21 VT/VF episodes in 11 pts treated 20/21 first shock success 3 inappropriate shocks Klein et al, PACE, 2010
Summary LifeVest is able to bridge a period with a high risk for SCD effectively temporarily in pts with established high risk in pts with temporarily increased risk or when risk can not be determined yet The LifeVest detects and terminates ventricular tachyarrhythmias with high efficacy. Patient compliance is high - even under clinical conditions. Rate of inappropriate shocks is low. About 40% of pts received an ICD. Patient selection, training, and compliance are essential.
Representation in Guidelines ACC/AHA/ESC 2006 Guidelines for management of patients with ventricular arrhythmias and prevention of sudden cardiac death 2006 International Society for Heart and Lung Transplantation guidelines for the care of cardiac transplant candidates 2006 Heart Rhythm considerations in heart transplant candidates and considerations for venrtricular assist devices 2009 Transvenous lead extraction: Heart Rhythm Society expert consensus on facilities, training, indications, and patient management 2014 Konsensuspapier der Deutschen Gesellschaft für Pneumologie und Beatmungsmedizin 2014 EHRA/HRS/APHRS Expert consensus on ventricular arrhythmias 2014 HRS/ACC/AHA Expert consensus statement on the use of ICD therapy in patients who are not included or not well represented in clinical trials 2014 AHA/ACC Guideline for the management of patients with non-st elevation acute coronary syndromes 2015 DGK Stellungnahme zum Einsatz des tragbaren Kardioverter/Defibrillators
Possible Indications Established ICD Indication - postponed Impl - Infection/Expl Severe Heart Failure - awaiting transplantation Bridging a temporarily increased risk - post complicated MI - post revascularisation low EF - myocarditis/newly diagnosed CM - SCD suvivors with reversible cause
DINAMIT study: 674 pts, MI 6-40 d, LVEF 35%, autonomic imbalance (HRV) Rate of sudden death or cardiac arrest with resuscitation according to time after myocardial infarction. Hohnloser NEJM 2004 IRIS study, 898 pts, LVEF <40%, <31d post MI Sarah Zaman, and Pramesh Kovoor Circulation. 2014;129:2426-2435 Copyright American Heart Association, Inc. All rights reserved Steinbeck, NEJM 2009
DINAMIT study: 674 pts, MI 6-40 d, LVEF 35%, autonomic imbalance (HRV) Rate of sudden death or cardiac arrest with resuscitation according to time after myocardial infarction. Hohnloser NEJM 2004 IRIS study, 898 pts, LVEF <40%, <31d post MI Sarah Zaman, and Pramesh Kovoor Circulation. 2014;129:2426-2435 Copyright American Heart Association, Inc. All rights reserved Steinbeck, NEJM 2009
8453 MI pts, 63y, 73% male PCI 309 apropriate shocks in 133 pts (1.6%) EF <30% n=106 EF 30-35% n=17 EF >30% n=8 12 pts died 3 pts VT not detected 34 pts brady/asystole 121 survivors (1.4%) CABG Epstein, JACC 2013 Zishiri, Circ Arrhythm Electrphysiol 2013
HOWEVER: There is no randomized study!