CE-454610-1 VENTRICULAR FIBRILLATION REQUIRING EXTRACORPOREAL RESUSCITATION DURING RADIOFREQUENCY ABLATION IN THE CORONARY SINUS

Abstract

Coronary vasospasm is a rarely reported but potentially catastrophic complication of radiofrequency ablation (RFA). The mechanism is not fully understood but may be related to thermal energy transfer, inflammatory markers released during ablation, and/or alterations in autonomic tone from stimulation of epicardial ganglionated plexi. While most vasospasm occurrences appear subclinical and self-limited, there are exceptions. To highlight an exceptional, life-threatening case of RFA-induced coronary vasospasm. N/A A 62-year-old man with persistent AF and five prior ablations (including one at our institution) presented for ablation of atypical atrial flutter. Termination of the flutter occurred with RFA (7 lesions) at the left atrial roof. There was also a breakthrough of conduction through a prior posterior mitral isthmus line, so coronary sinus (CS) lesions were placed to re-attain mitral block. Two irrigated RF lesions (#1 - 59 seconds, max 26 Watts; #2 - 40 seconds, max 33 Watts) were placed, but 7 seconds into the 3rd lesion (max 27 Watts), ventricular fibrillation (VF) occurred, initially refractory to multiple external shocks. ACLS/CPR commenced. Arterial access was rapidly achieved, and initial coronary angiography simply revealed diffusely slow/no flow related to ongoing VF. Emergent veno-arterial extracorporeal membrane oxygenation (VA ECMO) cannulation was initiated, following which the VF was successfully defibrillated, converting to sinus rhythm. Repeat coronary angiography revealed (known) minimal non-obstructive coronary disease as well as a focal, severe spasm of a dominant left circumflex artery adjacent to the location of CS ablation. Intracoronary nitroglycerin resulted in minimal initial angiographic improvement, so balloon angioplasty and deployment of a drug eluting stent was performed (post: TIMI III flow). The patient made a full recovery and was discharged home on post-procedure day 6 without long-term sequelae. This case underscores a life-threatening complication of RFA within the CS leading to coronary vasospasm and refractory VF. Expedient intervention with extracorporeal resuscitation and support can stabilize patients to allow time to manage arrhythmias and resolve spasm either pharmacologically or procedurally.