Early Risk of Mortality After Coronary Artery Revascularization in Patients With Left Ventricular Dysfunction and Potential Role of the Wearable Cardioverter Defibrillator

Abstract

Background Implantable cardioverter defibrillator (ICD) implantation for prevention of sudden cardiac death is typically deferred for 90 days after coronary revascularization, but mortality may be highest early after cardiac procedures in patients with ventricular dysfunction. We determined mortality risk in post-revascularization patients with left ventricular ejection fraction (LVEF) ≤35% and compared survival to those discharged with a wearable cardioverter defibrillator (WCD). Methods and Results Hospital survivors after surgical (CABG) or percutaneous (PCI) revascularization with LVEF≤35% were included from Cleveland Clinic and national WCD registries. Kaplan-Meier, Cox proportional hazards, propensity score-matched survival and hazard function analyses were performed. Early mortality hazard was higher among 4149 patients discharged without a defibrillator compared to 809 with WCDs (90-day mortality post-CABG 7% vs. 3%, p=0.03; post-PCI 10% vs. 2%, p<0.0001). WCD use was associated with adjusted lower risks of long-term mortality in the total cohort (39%, p<0.0001) and both post-CABG (38%, p=0.048) and post-PCI (57%, p<0.0001) cohorts (mean follow-up 3.2 years). In propensity-matched analyses, WCD use remained associated with lower mortality (58% post-CABG, p=0.002; 67% post-PCI, p<0.0001). Mortality differences were not attributable solely to therapies for ventricular arrhythmia. Only 1.3% of the WCD group had a documented appropriate therapy. Conclusions Patients with LVEF≤35% have higher early compared to late mortality after coronary revascularization, particularly after PCI. As early hazard appeared less marked in WCD users, prospective studies in this high risk population are indicated to confirm whether WCD use as a bridge to LVEF improvement or ICD implantation can improve outcomes after coronary revascularization.

2016 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure

“…U pacjentów z wysokim ryzykiem wystąpienia migotania komór można w takiej sytuacji rozważyć zastosowanie kamizelki defibrylującej. Nie ma jednak dowodów z badań randomizowanych potwierdzających skuteczność takiego postępowania [239][240][241].…”

“…chorzy z niską LVEF w pierwszym okresie po AMI i możliwością powrotu funkcji skurczowej lub chorzy oczekujący na przeszczepienie serca), można na pewien czas rozważyć zastosowanie kamizelki defibrylującej (zewnętrzny defibrylator z elektrodami przytwierdzanymi do zakładanej kamizelki), która jest urządze-niem rozpoznającym i przerywającym VT/migotanie komór [239][240][241]260]. Takie urządzenia nie zostały jednak jeszcze przebadane w RCT.…”

Wearable Cardioverter-Defibrillator Therapy for the Prevention of Sudden Cardiac Death

“…Consistent with prior data, however, only 1.3% of those treated with a WCD received appropriate therapy for VT/VF. 54 WCD therapy may also be a reasonable treatment option in appropriate pediatric patients at high risk of SCD. 44,50 Although there is an accumulating series of observational data of WCD use in clinical practice, questions about device efficacy will ultimately require randomized studies.…”

“…Given the presumed risk of SCD for these individuals during the waiting period, the WCD may provide a bridge of protection in patients within 90 days of CABG or PCI. 48,52,54 …”

Sudden Cardiac Death in Heart Failure

“…Recent studies show a benefit in the early post-myocardial infarction period or after revascularization, with about 1.5% of patients having an appropriate defibrillation. 70 Because it has been shown that as many as 28% of patients can improve their function significantly using appropriate neurohormonal antagonists, 71 it is reasonable to use this strategy as SCD protection while giving the chance for myocardial recovery. A summary of pharmacologic and electrical treatment strategies for SCD prevention in patients with heart failure is listed in Table 3.…”