Efficacy and safety of ajmaline in patients with electrical storm

Antiarrhythmic drug therapy is a cornerstone in managing electrical storm (ES). Data on the safety and efficacy of antiarrhythmic drugs besides beta-blockers and amiodarone are limited.

This retrospective observational study aimed to assess the potential role of ajmaline in patients with ES refractory to guideline-recommended care.

Adult patients admitted to the intensive care unit owing to ES between 2013 and 2023 who received ajmaline for therapy-refractory ES were retrospectively analyzed.

46 of 332 patients with recurrent ventricular tachycardia/ventricular fibrillation (mean age 64 ± 11 years; 93% male; mean left ventricular ejection fraction 33% ± 12%; 78% with implanted implantable cardioverter-defibrillator) were treated with intravenous ajmaline. Most patients (98%) had known structural heart disease. Serious adverse events requiring discontinuation were not observed. Minor adverse events occurred in 3 patients (7%). Complete arrhythmia suppression was achieved in 34 patients (74%), partial suppression in 2 (4%), and ventricular tachycardia slowing in 5 (11%). In 5 patients (11%), ajmaline showed no effect. During hospitalization, 5 patients (11%) died: 2 (4%) because of multiorgan failure and 3 (7%) because of a combined septic and cardiogenic shock despite complete or partial arrhythmia suppression by ajmaline. 28 patients (61%) underwent catheter ablation, and 41 patients (89%) were discharged in stable rhythm. After a 6-month follow-up, 15 patients were lost to follow-up and 24 of the 26 remaining patients were still alive.

In selected patients with refractory ES, intravenous ajmaline treatment was associated with a reduction in ventricular arrhythmias and a favorable safety profile. Ajmaline may serve as a valuable bridge to definitive treatment in life-threatening ES.