Characterization of patients with acute chest pain using cardiac magnetic resonance imaging.

AIMS: The purpose of this study was to evaluate whether CMRI provides characteristic findings in patients with acute chest pain suffering from ST-elevation-myocardial infarction (STEMI), non-ST-elevation myocardial infarction (NSTEMI), acute myocarditis or Tako-tsubo cardiomyopathy. PATIENTS AND METHODS: 230 consecutive patients with acute chest pain underwent cardiac catheterization followed by CMRI within median 5 days. Patients were classified to suffer from STEMI (n = 102), NSTEMI (n = 89), acute myocarditis (n = 27), or Tako-tsubo cardiomyopathy (n = 12) on the synopsis of all clinical data. Wall motion abnormalities, late enhancement (LE), persistent microvascular obstruction as well ventricular volumes and functions were assessed by CMRI.
RESULTS: Right and left ventricular volumes were significantly different between the groups and values were highest in patients with acute myocarditis. Wall motion abnormalities were observed in 100% of STEMI, 75% of NSTEMI, 67% of acute myocarditis and 100% of Tako-tsubo patients. There was a characteristic pattern of abnormal wall motion focused on midventricular-apical segments in patients with Tako-tsubo cardiomyopathy, depending on the culprit vessel in patients with STEMI/NSTEMI and with a random distribution in patients with acute myocarditis. LE was mainly subendocardial or transmural in patients with STEMI (93.2%) or NSTEMI (62.9%). LE was diffuse, intramural or subepicardial in patients with acute myocarditis. No LE was observed in patients with Tako-tsubo cardiomyopathy. Persistent microvascular obstruction was only visualized in patients with STEMI (33%) or NSTEMI (6%).
CONCLUSIONS: Cardiac magnetic resonance imaging provides characteristic patterns of LE, persistent microvascular obstruction and wall motion abnormalities that allow a differentiation between patients with acute chest pain from coronary and non-coronary origin.