Esteve-Ruiz Irene, Moraleda-Salas Maria Teresa, Amigo-Otero Emilio, Moreno Javier, Morina-Vazquez Pablo
Arrhythmia Unit, Department of Cardiology, Hospital Juan Ramon Jimenez, Ronda Norte S/N, Huelva 21005, Spain.
Cardiology Department, Hospital Ramón y Cajal, M-607, Km. 9, 100, Fuencarral-El Pardo, Madrid 28034, Spain.
Eur Heart J Case Rep. 2025 Aug 21;9(9):ytaf406. doi: 10.1093/ehjcr/ytaf406. eCollection 2025 Sep.
Becker muscular dystrophy (BMD) is frequently associated with cardiac involvement. The underlying pathoanatomical substrate includes replacement of cardiomyocytes by fibrous tissue, leading to extensive myocardial fibrosis of the posterolateral wall of the left ventricular (LV) epicardium. Cardiac arrhythmias, including ventricular tachycardia (VT), are common in this condition, particularly when LV ejection fraction (LVEF) declines.
A 45-year-old male with dilated cardiomyopathy due to BMD presented for routine follow-up of his implantable cardioverter defibrillator (ICD). Device interrogation revealed multiple episodes of sustained VT, some terminated by antitachycardia pacing. Echocardiogram showed a mildly dilated LV with LVEF of 30%. In April 2024, he experienced an appropriate ICD shock for sustained VT, and substrate ablation was scheduled. Relying on predominant epicardial fibrosis known to BMD, a direct epicardial approach was performed and electroanatomical mapping (EAM) of the posterobasal LV revealed a large area of delayed, fractionated, and low-voltage electrograms (EGMs). Extensive ablation was performed with meticulous application near the atrioventricular annulus and left phrenic nerve region. Repeat EAM showed near-complete abolition of delayed potentials. No endocardial ablation was performed. Ventricular tachycardia remained non-inducible, and no sustained episodes or ICD shocks have been recorded during the 9-month follow-up.
Direct epicardial access may be the preferred ablation strategy for some cardiomyopathies such as BMD, where the arrhythmic substrate is epicardial. Detailed EAM with annotation of abnormal EGMs is crucial before ablation, and special care must be taken to avoid injury to critical structures such as the phrenic nerve or coronary arteries.
贝克肌肉营养不良症（BMD）常伴有心脏受累。潜在的病理解剖学基础包括心肌细胞被纤维组织替代，导致左心室（LV）心外膜后外侧壁广泛心肌纤维化。心律失常，包括室性心动过速（VT），在这种情况下很常见，尤其是当左心室射血分数（LVEF）下降时。
一名45岁男性因BMD导致扩张型心肌病，前来对其植入式心律转复除颤器（ICD）进行常规随访。设备问询显示多次持续性室性心动过速发作，部分发作通过抗心动过速起搏终止。超声心动图显示左心室轻度扩张，左心室射血分数为30%。2024年4月，他因持续性室性心动过速接受了适当的ICD电击，计划进行基质消融。鉴于已知BMD主要存在心外膜纤维化，采用直接心外膜入路，对左心室后基底进行电解剖标测（EAM），发现大面积延迟、碎裂和低电压心电图（EGM）。在房室环和左膈神经区域附近进行了细致的广泛消融。重复EAM显示延迟电位几乎完全消失。未进行心内膜消融。室性心动过速仍不可诱发，在9个月的随访期间未记录到持续性发作或ICD电击。
对于某些心肌病，如BMD，心律失常基质位于心外膜，直接心外膜入路可能是首选的消融策略。在消融前，对异常EGM进行标注的详细EAM至关重要，必须特别小心避免损伤膈神经或冠状动脉等关键结构。
