[Myocardial infarction with ST segment elevation and angiographically normal coronary arteries: epidemiology and mid-term follow-up].

BACKGROUND AND OBJECTIVE: The myocardial infarction (MI) with ST elevation and angiographically normal coronary arteries isn't frequent. The aim of this study is to describe clinical characteristic and mid-term follow-up of those patients.

PATIENTS AND METHOD: Between January 1997 and December 2004 we identified 75 patients with MI and normal coronary arteries in a coronary angiography performed within one month of the AMI. All had criteria of MI and their coronary arteries were smooth and without obstructive lesions.

RESULTS: The incidence was 3%, and mean age (standard deviation): 49 (11) years; 63% of patients were males and 47% were smokers, 33% had hypertension, 24% dislipemia and 9% diabetes. No patient had previous angina. MI location was anterior in 43%, inferior in 40% and lateral in 17%. The peak of creatine phosphokinase was 700 U/dl (range: 431-1,115) and the ejection fraction was 65% (14%). After a medium follow up of 30 months (range: 12-84) the events were: one death and 2 new MI.

CONCLUSIONS: MI with normal coronary arteries is rare, is associated with a relative low rate of coronary risk factors, and with a good initial outcome, low rate of recurrent events and preservation of left ventricular function.