Abstract
During transcatheter mitral valve repair (TMVR), atrial arrhythmias, such as atrial fibrillation with tachycardia, can be restored to sinus rhythm with electrical cardioversion (EC) to facilitate the procedure. However, it is difficult to determine the safety of performing EC in cases of atrial functional mitral regurgitation (AFMR), especially in serious cases with severe tachycardia. Our patient was a woman in her 80s with atrial flutter, a heart rate of 140 bpm, and detached mitral valve leaflets. At the time of TMVR, EC restored her sinus rhythm to 80 bpm, but the mitral valve leaflets became more detached and she experienced circulatory collapse. A cardiac pacing (CP) rate of 120 bpm reduced the separation of the mitral valve leaflets and restored circulation. The rapid decrease in heart rate due to EC caused an excessive increase in left atrial and left ventricular filling, and the combination of atrial and ventricular mechanisms may have contributed to the further separation of the mitral valve leaflets. The recovery of left atrial contraction and the increase in heart rate after CP may have contributed to the reduction in mitral valve leaflet separation. When planning rate control or return to sinus rhythm in serious AFMR with atrial arrhythmias presenting as severe tachycardia, it is important to fully consider the indications for EC, and to be prepared for rapid heart rate control with CP considering the risk of circulatory collapse when performing EC.
