ECMO for drug‐refractory electrical storm without a reversible trigger: a retrospective multicentric observational study

Abstract

AimsDrug‐refractory electrical storm (ES) is a life‐threatening medical emergency. We describe the use of venoarterial extracorporeal membrane oxygenation (VA‐ECMO) in drug‐refractory ES without a reversible trigger, for which specific guideline recommendations are still lacking.Methods and resultsRetrospective observational study in four Iberian centres on the indications, treatment, complications, and outcome of drug‐refractory ES not associated with acute coronary syndromes, decompensated heart failure, drug toxicity, electrolyte disturbances, endocrine emergencies, concomitant acute illness with fever, or poor compliance with anti‐arrhythmic drugs, requiring VA‐ECMO for circulatory support. Thirty‐four (6%) out of 552 patients with VA‐ECMO for cardiogenic shock were included [71% men; 57 (44–62) years], 65% underwent cardiopulmonary resuscitation before VA‐ECMO implantation, and 26% during cannulation. Left ventricular unloading during VA‐ECMO was used in 8 (24%) patients: 3 (9%) with intraaortic balloon pump, 3 (9%) with LV vent, and 2 (6%) with Impella. Thirty (88%) had structural heart disease and 8 (24%) had an implantable cardioverter‐defibrillator. The drug‐refractory ES was mostly due to monomorphic ventricular tachycardia (VT) and ventricular fibrillation (VF) (59%), isolated monomorphic VT (26%), polymorphic VT (9%), or VF (6%). Thirty‐one (91%) required deep sedation, 44% overdrive pacing, 36% catheter ablation, and 26% acute autonomic modulation. The main complications were nosocomial infection (47%), bleeding (24%), and limb ischaemia (21%). Eighteen (53%) were weaned from VA‐ECMO, and 29% had heart transplantation. Twenty‐seven (79%) survived to hospital discharge (48 (33–82) days). Non‐survivors were older [62 (58–67) vs. 54 (43–58); P < 0.01] and had a higher first rhythm disorder‐to‐ECMO interval [0 (0–2) vs. 2 (1‐11) days; P = 0.02]. Seven (20%) had rehospitalization during follow‐up [29 (12–48) months], with ES recurrence in 6%.ConclusionsVA‐ECMO bridged drug‐refractory ES without a reversible trigger with a high success rate. This required prolonged hospital stays and coordination between the ECMO centre, the electrophysiology laboratory, and the heart transplant programme.