Myocardial perfusion scintigraphy in myocardial infarction — impact of ST-segment elevation and of Diabetes mellitus

Myocardial perfusion scintigraphy (MPS) is frequently used in the evaluation of patients with coronary artery disease, either stable or with the prior remote acute coronary syndrome. The goal of the present work was to evaluate changes in MPS according to the nature of the infarction (ST-elevation vs non-ST elevation status) as well as according to the presence or absence of Diabetes mellitus. A prospective study of 124 consecutive patients with myocardial infarction (MI) was carried out using MPS. Patients with ST-segment elevation MI (STEMI) had significantly larger values both for percentage and absolute areas of perfusion defects, both at rest and in a stress situation, when compared to patients without ST-segment elevation (NSTEMI). These patients had significantly lower values for left ventricular ejection fractions (EF), in a similar comparison. The values for perfusion defects at rest for STEMI patients were more than double the values for NSTEMI patients (17.1 ± 14.6% vs 6.5 ± 7.8%, P< .001). Concerning resting left ventricular EF, STEMI patients had a mean value of 47.6 ± 13.6% and NSTEMI patients had a mean value of 53.2 ± 12.4% (P.026). Regarding the comparison between patients with and without Diabetes mellitus, none of the parameters under study showed significant differences. Linear regression analysis, taking the percentage of perfusion defect, as the dependent variable, yielded an overall significant result, however, only ST-segment elevation was shown to have an individually significant result. We conclude that the presence of ST-segment elevation but not the presence of Diabetes mellitus is associated with different patterns of MPS in patients with MI.