Clinical Impact and Prediction of Early Electrical Storm in Patients With Left Ventricular Assist Device

Although ventricular arrhythmias (VAs) are common after left ventricular assist device (LVAD) implantation, the features of early electrical storm (ES) remain poorly characterized.

This study aimed to evaluate the incidence and clinical impact of early ES in LVAD recipients.

This international, multicenter, retrospective study included 1,309 recipients of LVADs implanted between 2006 and 2019. Early ES was defined as ≥3 sustained VA episodes within 24 hours during the first 30 days' postimplantation. The primary outcome was 3-month all-cause mortality. Secondary endpoints included 3-month cardiac mortality and early (≤30 days) right ventricular (RV) failure.

Early ES occurred in 56 patients (4.3%), with a median onset at 5 days' postimplantation. Patients with early ES experienced higher 3-month all-cause mortality (adjusted HR [aHR]: 3.09; 95% CI: 1.91-5.01; P < 0.01) and increased early RV failure (aHR: 2.05; 95% CI: 1.10-3.92; P = 0.03). Notably, early VA without ES showed no prognostic impact. Multivariable analysis identified 4 independent predictors of early ES: pre-LVAD RV S' wave ≤9.5 cm/s (aHR: 2.25; 95% CI: 1.23-4.14), heart failure duration of ≥5 years (aHR: 2.41; 95% CI: 1.10-5.28), history of VAs (aHR: 4.43; 95% CI: 2.21-8.87), and prior mechanical circulatory support (aHR: 6.40; 95% CI: 2.12-19.33). The EarlyES-LVAD score, based on these variables, showed good discrimination (C-statistic 0.75) and stratified patients into low-risk (score 0-1), intermediate-risk (score 2-3), and high-risk (score 4-6) groups, with corresponding early ES rates of 1.1%, 3.9%, and 12.4%.

Early ES, but not isolated early VAs, is associated with substantially worse outcomes in LVAD recipients. The EarlyES-LVAD score enables practical risk stratification, facilitating targeted therapeutic interventions in high-risk patients.