This report describes the clinical characteristics of 8 consecutive patients with transient left ventricular apical ballooning identified among 389 patients (2%) admitted to a tertiary referral hospital with suspected acute coronary syndromes over a 1-year period. Among these patients, 2 cases appeared to be caused by acute myocarditis and 1 case by head trauma with intracranial bleeding. In the remaining 5 cases, no apparent cause was found. All patients but 1 were postmenopausal women (mean age 60 +/- 13.5 years). Preceding strong emotional or physical stress was present in 6 patients. The presenting symptom in 7 patients was chest pain. Four patients had significant ST-segment elevation, and the remaining 4 had T-wave inversions on their admission electrocardiograms. Mean peak troponin I was moderately elevated (3.7 +/- 4.5 ng/dl). The mean echocardiographic left ventricular ejection fraction was 40 +/- 10% on admission and increased significantly to 63 +/- 4% at 1-month follow-up (p <0.0001). All patients but 1 had abnormal corrected Thrombolysis In Myocardial Infarction frame counts (>27 frames) in >or=1 major epicardial coronary artery. All patients were alive and without major adverse cardiac events at 6-month follow-up. In conclusion, transient left ventricular apical ballooning should be considered in the differential diagnosis of patients presenting with suspected acute coronary syndromes, because it may account for approximately 2% of hospital admissions.