Apical ballooning syndrome or aborted acute myocardial infarction? Insights from cardiovascular magnetic resonance imaging.

INTRODUCTION: Apical Ballooning Syndrome (ABS) is a novel acute cardiac syndrome that mimics acute myocardial infarction (AMI). This study evaluates the diagnostic utility of cardiac magnetic resonance imaging (CMR) in patients with suspected ABS. METHODS AND MATERIALS: Contrast-enhanced CMR was performed in 13 consecutive patients with suspected ABS on the basis of their initial clinical presentation and cardiac catheterization results.
RESULTS: Ten patients (all female, mean age 71 +/- 8 years) had an eventual diagnosis of ABS. CMR demonstrated left ventricle regional wall motion abnormalities (RWMA) involving the apex and mid-ventricle. Six also had right ventricular apical akinesis. There was no myocardial delayed enhancement (MDE) in these patients. The remaining three patients had initial features suggestive of ABS but were eventually determined to have AMI. Left ventriculography showed typical apical ballooning that was not explained by coronary angiography results. Two had MDE and persistent RWMA consistent with anterior AMI. One had RWMA on CMR consistent with a single vascular territory, and subsequent intravascular ultrasound showed obstructive plaque in the left anterior descending (LAD) artery. The final diagnosis in these patients was AMI with clot lysis prior to coronary angiography.
CONCLUSION: While ABS mimics AMI, AMI with spontaneous clot lysis may also mimic ABS, and at least in some patients, be mistaken for ABS. ABS is characterized by the absence of MDE and complete myocardial viability on CMR. The diagnosis of ABS can be excluded if CMR demonstrates MDE consistent with myocardial necrosis in a pattern and distribution consistent with AMI.