Objectives .– Among patients presenting with chest pain, troponin elevation and non obstructed coronary arteries, diagnosis is important for prognostic stratification and treatment. However, many conditions can lead to this presentation. We sought to assess the diagnostic value of cardiac magnetic resonance (CMR) in this setting.

Patients and methods .– From January 2009 to December 2012, 108 consecutive patients with chest pain, troponin elevation and unobstructed coronary arteries on coronary angiography underwent a CMR study with cine imaging, T2 weighted imaging for detection of inflammation and late gadolinium enhancement imaging for detection of infarction/fibrosis.

Results .– Mean age was 54 ± 17 years and 54 (50%) were men. Mean peak troponin I level was 5.49 ± 7.3 ng/mL (range: 0.1–40). The median interval from presentation of chest pain to CMR was 5 days. CMR lead to a formal diagnosis in 76 (70.3%) patients. The final diagnosis was acute myocarditis in 32 (29.6%) patients, acute myocardial infarction in 24 (22.2%) patients, stress cardiomyopathy in 16 (14.8%) patients, hypertrophic cardiomyopathy in two cases (1.8%) and cardiac amyloidosis in two cases (1.8%). In 25 (23.1%) patients, the CMR was normal. Patients with normal CMR had a lower mean peak level of troponin (1.75 ng/mL) than patients who have abnormal examination (6.69 ng/mL) ( P = 0.001).

Conclusion .– Among patients admitted with chest pain, troponin elevation and non obstructed coronary arteries, CMR establishes a definite diagnosis in more than 2/3 of patients and is useful to discriminate patients who need secondary prevention treatment. Normal CMR seems to be correlated with a smaller myocardial injury.