Troponin I in atrial fibrillation with no coronary atherosclerosis

A number of reports have raised the possibility that myocardial strain could be associated to increased plasma levels of troponin I. A 69-year-old, male, Caucasian, patient was admitted with prolonged chest pain and dyspnoea. The electrocardiogram showed atrial fibrillation with a ventricular rate of about 120 to 150/minute. After treatment with digoxin and amiodarone, the patient returned to sinus rhythm. An elevation in the plasma levels of troponin I was noted, with a maximum value of 0.66 ng/ml. Coronary angiography showed absence of coronary artery atherosclerotic lesions. Atrial fibrillation of recent onset and with a relatively high heart rate may be yet another situation in which acute myocardial strain could be the cause of the abnormal release of cardiac troponin I.