Background and aim: Recently published studies suggest that percutaneous coronary inetrvention (PCI) is superior to fibrinolysis in terms of early and late mortality in patients with acute myocardial infarction (MI) with ST-elevation. The aim of this study was to evaluate the influence of treatment strategy in the acute phase of MI on postinfarction functional capacity.
Patients and methods: This prospective study included 128 consecutive patients with MI, with ST-elevation over 12 weeks from the disease onset. There were 92 (72%) male and 36 (28%) female patients, mean age 59 +/- 10 years. Inclusion criteria were age under 70, first MI with ST-elevation, and sinus rhythm. Exclusion criteria were previous MI, non ST-elevation MI, acute heart failure, atrial fibrillation, unstable angina pectoris, re-IM or necessity for coronarography and PCI during rehabilitation, and other acute disease. Patients were divided into three groups according to treatment modality: group 1, 38 (30%) patients treated with primary PCI; group 2, 46 (36%) patients treated with fibrinolysis; and group 3, 44 (34%) conservatively treated patients. There were no significant between-group differences according to age, sex, risk factors for coronary artery disease, infarct site, and frequency of complications in the acute phase of MI. The functional capacity of patients was evaluated by symptom-limited exercise test. Echocardiographic examinations were also done in each patient. Statistical analysis was performed by using the commercial software package, Microsoft SPSS for Windows, Version 8.0. Results were expressed as a mean standard deviation. Differences between the groups were tested by analysis of variance (ANOVA) and post hoc Tuckey test. The value of p < 0.05 was considered statistically significant.
Results: At the end of rehabilitation, the mean values of exercise capacity in groups 1, 2 and 3 were 6.1 +/- 1.3, 5.5 +/- 1.2, and 4.8 +/- 1.3 METs, respectively (group 1 vs. 2, p = 0.03; group 1 vs. 3, p < 0.001; group 2 vs. 3, p = 0.01). The mean values of ejection fraction in groups 1, 2 and 3 were 56 +/- 10, 53 +/- 9 and 47 +/- 11, respectively (group 1 vs. 2, p = 0.03; group 1 vs. 3, p < 0.001: group 2 vs. 3, p = 0.009). Four (3%) patients were excluded from the study because of complications during rehabilitation treatment.
Conclusion: Postinfarction functional capacity in patients with MI depends on treatment strategy in the acute phase of disease. Patients who underwent PCI in the acute phase of MI had a higher functional capacity and better preserved systolic function of the left ventricle in comparison with patients who received fibrinolysis or those who were treated conservatively.