Background: Antiarrhythmic drug (AAD) therapy is a cornerstone of the complex management of patients with an electrical storm (ES). Data on the safety and efficacy of AADs besides beta-blockers and amiodarone are limited.
Objective: This retrospective observational study aimed at assessing the potential role of ajmaline in patients with ES refractory to guideline-recommended care.
Methods: Adult patients admitted to the ICU at our tertiary centre between March 2013 and December 2023 who received ajmaline for therapy-refractory ES were retrospectively analysed.
Results: 46 out of 332 patients with recurrent VT/VF (mean age 64±11 years; 93% male; mean LVEF 33±12%; n=78% with implanted ICD) were treated with ajmaline due to ES that was refractory to guideline-recommended therapy. All but one patient (98%) had known structural heart disease. (n=29 ischaemic cardiomyopathy, n=16 non-ischaemic cardiomyopathy). Most patients (n=37, 80%) had sustained monomorphic VT whereas recurrent polymorphic VT and ventricular fibrillation (VF) occurred in 5 (11%) patients, in 4 patients (9%) both sustained monomorphic and polymorphic VT or VF occurred. After an initial i.v. bolus (n=16; 35%), ajmaline was administered continuously in nearly all patients (n=45; 98%). Serious adverse events requiring discontinuation of ajmaline therapy 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 slowing of VT in 5 (11%). In 5 patients (11%), ajmaline showed no effect. During hospitalization, 5 patients (11%) died; 2 (4%) due to multi-organ failure and 3 (7%) of a combined septic and cardiogenic shock despite complete or partial arrhythmia suppression by ajmaline. 28 patients (61%) underwent an electrophysiologic study aiming at VT 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.
Conclusion: In selected patients with refractory ES, ajmaline treatment was associated with a reduction in VAs and a favourable safety profile. Ajmaline may serve as a valuable bridge to definitive treatment in life-threatening ES.
