[Assessment of myocardial viability and recovery of the left ventricular function in postmyocardial infarction patients].

AIM: To evaluate prognostic significance of myocardial viability (MV) depending on treatment policy in postmyocardial infarction (PMI) patients.

MATERIAL AND METHODS: The study included 196 patients (172 males, 24 females, age 30-75, mean age 53 +/- 8.6 years). Standard stress dobutamine echocardiography was made 14 +/- 6 days (8-21 days) after macrofocal MI. Reperfusion therapy was made in 138 (70%) patients. X-ray contrast coronary angiography was performed in all the patients as the criterion of the immediate effect of reperfusion was achievement of residual stenosis of MI-related coronary artery < 50%. Late after MI (18 +/- 7 months after MI) a comparative analysis of the left ventricular function was made in three groups of patients depending on the clinical response to the treatment. MV criterion was based on a fall in the index of infarction zone wall movement (IZWM) under low-dose dobutamine stress test reflecting contractile reserve of the infarction zone (CR). Left ventricular function recovery was judged by a decrease in initial IZWM index 18 months later vs the initial IZWM 14 days later. Thus contractile reversibility of the infarction zone (CRIZ) was determined. LV function was also assessed by the index of left ventricular end diastolic volume (LVEDV), by the index of left ventricular end systolic volume (LVESV), left ventricular ejection fraction (LVEF).

RESULTS: 18 months after MI, CRIZ was higher in group 1 (after effective reperfusion) and group 3 (after myocardial revascularization) compared to group 2 (medication only): 0.33 +/- 0.01, 0.39 +/- 0.02 and 0.23 +/- 0.01, respectively. LVEDV and LVESV in group 1 and 3 diminished while LVEF increased. LVEDV in group 2 remained elevated though EF rose considerably.

CONCLUSION: Recovery of LV contractile function depends much on reestablishment of adequate myocardial perfusion by reperfusion therapy or myocardial revascularization. Chronic myocardial hypoperfusion leads to LV remodeling. CRIZ proved a significant prognostic criterion of the IZWM index 18 months after MI only in patients given effective reperfusion therapy.