Clinical Outcomes of Concurrent Ventricular Electrical Storm and Infection

Electrical storm (ES) is a cluster of sustained ventricular arrhythmias that may be caused by various triggers on the arrhythmic substrate. The association between infection and ES is unknown.

This study sought to investigate the clinical profile and prognosis of concurrent ES and infection.

Study investigators retrospectively studied patients with ES between May 2004 and March 2022. Participants were divided into 2 groups: those with infection (infection group) and those without concurrent infection (noninfection group). The study compared clinical outcomes and prognoses.

A total of 309 patients with ES were included; 68 had concurrent infection, and 28 of these patients had bacteremia. Among those with bacteremia, methicillin-resistant Staphylococcus aureus was the most common pathogen, with 9 patients (32.1%), and lead extraction was performed in 13 (46.4%). Among the patients who clearly did not have preceding infection, 15 (5.3%) developed bacteremia after ES. During the 2-year follow-up period, the infection group had significantly higher mortality than the noninfection group (log-rank P < 0.001). Multivariate logistic regression analysis identified bacteremia (OR: 5.23; 95% CI 1.91-15.02; P = 0.001) and decreased left ventricular ejection fraction (LVEF) (each 1% increase, OR: 0.95; 95% CI: 0.93-0.98; P = 0.002) as independent predictors of mortality.

Among patients with ES, those with concurrent infection have increased mortality. Of patients presenting without infection, >5% developed bacteremia after ES, thereby raising the possibility of iatrogenic infection during prolonged hospitalization. Bacteremia and decreased LVEF are independent predictors of mortality.