William Jeremy, Muthana Haider, Hogarty Joseph, Taylor Andrew, Hare James L, Mariani Justin, Patel Hitesh, Wong Geoff, Stub Dion, Kaye David M, Prabhu Sandeep, Kistler Peter M, Voskoboinik Aleksandr
The Alfred Hospital Melbourne Australia.
Monash University Melbourne Australia.
J Arrhythm. 2025 Jul 6;41(4):eJOA370109. doi: 10.1002/joa3.70109. eCollection 2025 Aug.
Conduction system disease may represent an early manifestation of underlying structural heart disease, including infiltrative disorders. Timely diagnosis of underlying cardiomyopathy has significant implications for clinical management, guiding both disease-modifying medical therapy and decisions around device implantation.
We sought to investigate the utility of cardiac magnetic resonance imaging (CMR) in patients with conduction system disease and preserved LV function on echocardiography.
We evaluated all patients undergoing CMR between 2005 and 2023 at our institution for the investigation of advanced conduction system disease (complete heart block, Mobitz II block, or bifascicular block). We excluded patients with known systolic heart failure (LVEF<50%) prior to CMR. We evaluated the prevalence of CMR-detected myocardial fibrosis and infiltrative cardiomyopathy in this cohort.
One hundred nineteen patients were identified (mean age 49 ± 15 years, 52% male). Complete heart block was the most common indication (50%), followed by bifascicular block (27%) and Mobitz II block (23%). Mean LVEF on echocardiography prior to CMR was 60.0 ± 3.1%. CMR-detected late gadolinium enhancement (LGE) was present in 32/119 patients (26.9%). Cardiac sarcoid was the most common final diagnosis ( = 19, 16%), of whom only five (26%) had known extracardiac sarcoid prior to CMR. Cardiac fibrosis was observed in a similar proportion of patients across the three subtypes of conduction disease studied ( = 0.47).
Cardiac fibrosis is present in a substantial proportion of patients undergoing CMR for the investigation of conduction disease, even when LV function appears preserved on echocardiography. Cardiac MRI may be an important adjunctive tool for the investigation of conduction disease, particularly in younger patients.
传导系统疾病可能是潜在结构性心脏病的早期表现，包括浸润性疾病。及时诊断潜在的心肌病对临床管理具有重要意义，可为改变疾病进程的药物治疗和设备植入决策提供指导。
我们旨在研究心脏磁共振成像（CMR）在传导系统疾病且超声心动图显示左心室功能正常的患者中的应用价值。
我们评估了2005年至2023年间在我院接受CMR检查以诊断晚期传导系统疾病（完全性心脏传导阻滞、莫氏Ⅱ型阻滞或双分支阻滞）的所有患者。我们排除了CMR检查前已知有收缩性心力衰竭（左心室射血分数<50%）的患者。我们评估了该队列中CMR检测到的心肌纤维化和浸润性心肌病的患病率。
共纳入119例患者（平均年龄49±15岁，52%为男性）。完全性心脏传导阻滞是最常见的适应证（50%），其次是双分支阻滞（27%）和莫氏Ⅱ型阻滞（23%）。CMR检查前超声心动图测得的平均左心室射血分数为60.0±3.1%。119例患者中有32例（26.9%）CMR检测到晚期钆增强（LGE）。心脏结节病是最常见的最终诊断（=19，16%），其中只有5例（26%）在CMR检查前已知有心脏外结节病。在所研究的三种传导疾病亚型中，观察到心脏纤维化的患者比例相似（=0.47）。
即使超声心动图显示左心室功能正常，在接受CMR检查以诊断传导疾病的患者中，相当一部分存在心脏纤维化。心脏磁共振成像可能是诊断传导疾病的重要辅助工具，尤其是在年轻患者中。
