Short and long-term outcomes of medical management of patients with a first episode of arrhythmic storm

Abstract Introduction There is few data about long-term outcomes of conservative management (without catheter ablation) of patients with a first episode of arrhythmic storm (AS) in the current context. This study analyzes the short and long-term outcomes of implantable cardioverter defibrillator (ICD) patients with a first episode of AS receiving non-interventional management. Methods Consecutive patients admitted with a first episode of AS between January 2008 and June 2019 receiving medical management without catheter ablation were included. AS was defined as 3 or more appropriate ICD therapies occurring during a 24 h span. Medical management included: correction of triggers, sedation/mechanical ventilation, antiarrhythmic drugs, ICD reprogramming and neuraxial modulation. Baseline clinical characteristics and follow-up data were recorded. All patients were followed every 6 months at the ICD office. The primary end-point was all-cause mortality. Results 60 patients (81% male, 62.8±16.2 years, 43% ischaemic, LVEF 35.4±14%) with a first episode of AS treated conservatively were included. Thirty-day survival was 96.5% and 1-year survival was 82%. During a median (interquartilic range) follow-up of 31 (6–69) months, 31 (51.7%) patients died (51.6% due to cardiovascular aetiology) and 35 (58.3%) patients were readmitted (48.5% due to recurrent arrhythmic events and 45.7% due to heart failure). Age [HR 1.05 (95% confidence interval: 1.01–1.08)] and end-diastolic diameter [HR 1.05 (95% confidence interval: 1–2)] were the strongest independent predictors of all-cause mortality. Conclusion Despite the severity of this entity, medical management (without catheter ablation) of a first episode of AS is reasonable given its good 30-day and 1-year survival. However, a high rate of AS recurrence and readmissions are observed during long-term follow-up. Efforts are needed in order to identify those patients with a first episode of AS that could benefit from an early catheter ablation strategy. Funding Acknowledgement Type of funding source: None