Broken heart during treadmill exercise testing: an unusual cause of ST-segment elevation.

Treadmill exercise testing is a commonly used diagnostic test for the assessment of chest discomfort and exercise-induced arrhythmias. The presence of ST-segment elevation during exercise is considered a marker of severe ischaemia, usually secondary to a critical lesion in a proximal coronary artery. We present a novel cause of ST-segment elevation during exercise testing: "broken heart syndrome", also known as transient left ventricular apical ballooning syndrome, or takotsubo cardiomyopathy. Takotsubo cardiomyopathy is a rare, yet well-described, reversible cardiomyopathy triggered by profound psychological or physical stress. The exact aetiology of takotsubo cardiomyopathy is still unknown. However, the occurrence of takotsubo cardiomyopathy during exercise in this case report is in keeping with the sudden catecholamine surge secondary to treadmill exercise testing, which leads to abnormal ventricular contraction and contributes to wall motion abnormalities. Further studies are needed to elucidate the pathogenesis of the disease and consequently determine specific preventive therapies.