Cardiac magnetic resonance imaging as a tool to link cardiac conduction disease to myocarditis with minimal left ventricular impairment.

Myocarditis is an injury of the myocardium caused by a variety of agents. Conduction disturbances such as complete atrioventricular block (AV block) may occur as an infrequent but serious complication of myocarditis. Early detection and accurate diagnosis of myocarditis are still unresolved challenges. We present 2 cases of otherwise mild myocarditis complicated by high-degree AV block in combination with isolated delayed uptake of contrast at the septal regions in the cardiac magnetic resonance imaging. Because the AV block was persistent in both cases, permanent pacemaker implantation was necessary. Delayed enhancement in the septal area in myocarditis might be predictive of infra-Hisian AV block.