Prognostic Impact of Recurrences in Patients with Electrical Storm.

OBJECTIVES: The study sought to assess the prognostic impact of recurrences of electrical storm (ES-R) on mortality, rehospitalization and major adverse cardiac events (MACE).

BACKGROUND: Data on the prognostic impact of ES-R is rare.

METHODS: All consecutive ES patients with implantable cardioverter defibrillator (ICD) were included retrospectively from 2002 to 2016. Patients with ES-R were compared to patients without ES-R. The primary prognostic endpoint was all-cause mortality, secondary endpoints were in-hospital mortality, rehospitalization rates and MACE.

RESULTS: A total of 87 ES patients with ICD were included, of which 26% presented ES-R at 2.5 years of follow-up. ES-R patients revealed lower LVEF compared to no ES-R patients (91% vs. 61%; p = 0.081). There was a higher rate of the primary prognostic endpoint all-cause mortality at 2.5 years (50% vs. 32%; log-rank p = 0.137). Furthermore, ES-R was associated with increasing rates of rehospitalization (64% vs. 37%; p = 0.031; HR 1.985; 95% CI 1.025-3.845; log-rank p = 0.042), especially of acute heart failure (32% vs. 12%; p = 0.001; HR 3.262; 95% CI 1.180-9.023; log rank p = 0.023). MACE were higher in ES-R patients (55% vs. 35%; p = 0.113; log rank p = 0.141). ES patients with LVEF ≤35% were 12.4 times more likely to develop ES-R (HR 12.417; 95% CI 1.329-115.997; p = 0.027).

CONCLUSION: At long-term follow-up of 2.5 years, ES-R was associated with numerically higher long-term all-cause mortality and with significantly increasing rates of re-hospitalization due to acute heart failure. LVEF ≤35% was associated with increased risk of ES-R.