Sudden cardiac arrest due to atrioventricular block: A diagnostic challenge.

Sudden cardiac arrest survivors continue to be a challenge for cardiologists. An appropriate initial diagnostic approach is crucial for planning a successful therapeutic strategy. We report the case of a 62-year-old woman who suffered an out-of-hospital cardiac arrest due to third-degree atrioventricular (AV) block. Despite suspected acute coronary syndrome, the coronary angiogram proved inconclusive, while cardiac magnetic resonance imaging ruled out other differential diagnoses such as acute myocarditis. The reversible nature of the AV block rendered permanent pacing unnecessary.