Objective The aim of the study was to explore the influencing factors of exercise tolerance in patients with myocardial infarction (MI) after percutaneous coronary intervention (PCI) revascularization in acute state. Methods A total of 112 patients with first MI undergoing PCI revascularization in acute state and completing cardiopulmonary exercise testing (CPET) were enrolled. Exercise capacity was evaluated by peak oxygen consumption percentage (VO2 peak%) in CPET. Patients were divided into normal exercise capacity (NEC) group (n=40) and abnormal (AEC) group (n=72) according to VO2 peak% value. Clinical manifestations, histories of hypertension and diabetes, medications, coronary arterial angiography and echocardiography findings of patients were compared. The onsets of diabetes and blood glucose levels during the period of CPET were evaluated in the MI patients with diabetes. The patients were followed up for major adverse cardiovascular events (MACE) (admission due to chest pain, re?revascularization, re?infarction and all?cause death) within 24 months after PCI. Multivariate logistic regression analyses were conducted to examine influencing factors for exercise tolerance. Results The ratio of diabetes, type C lesions in the AEC group were higher than those in the NEC group (diabetes: 37.5% vs. 17.5%; type C lesions: 69.4% vs. 42.5%, respectively, all P<0.05). The left ventricular ejection fraction (LVEF) in patients in the AEC group was lower than that in the NEC group [(60.6±10.0) % vs. (65.0±8.2) %, P=0.019]. Multivariate logistic regression analyses showed that history of diabetes and history of type C lesions were the independent risk factors for the declined exercise capacity in the MI patients after PCI revascularization ( OR=3.14, 95%CI 1.167-8.362, P=0.023; OR=3.32, 95%CI 1.444-7.621, P<0.01). Among the MI patients with diabetes, the duration of diabetes in the AEC group was significantly longer than that in the NEC group[ (7.7 ± 3.6)years vs. (5.0 ± 2.4)years] and the proportions of subjects reaching target levels of fasting plasma glucose (40.7% vs. 57.1%) and glycosylated hemoglobin A1c(HbA1c) (55.6% vs. 71.4%) in this group were significantly lower than those in the NEC group (all P<0.05). A multivariate logistic regression analysis showed that reaching HbA1c target was an independent predictor of improved exercise tolerance in MI patients with diabetes who received PCI ( OR=2.518, 95%CI 1.395-7.022, P=0.021). No significant differences were observed in incidence of admission due to chest pain, re?revascularization and re?infarction between the two groups within 24 months after PCI between the groups. Conclusions Diabetes and type C lesions are independent risk factors of declined exercise capacity in patients with first myocardial infarction who received revascularization in acute state. Reaching target HbA1c is independent factor of improved exercise capacity in patients with myocardial infarction and diabetes.

Objective: The aim of the study was to explore the influencing factors of exercise tolerance in patients with myocardial infarction (MI) after percutaneous coronary intervention (PCI) revascularization in acute state. Methods: A total of 112 patients with first MI undergoing PCI revascularization in acute state and completing cardiopulmonary exercise testing (CPET) were enrolled. Exercise capacity was evaluated by peak oxygen consumption percentage (VO_{2 peak}%) in CPET. Patients were divided into normal exercise capacity (NEC) group (n=40) and abnormal (AEC) group (n=72) according to VO_{2 peak}% value. Clinical manifestations, histories of hypertension and diabetes, medications, coronary arterial angiography and echocardiography findings of patients were compared. The onsets of diabetes and blood glucose levels during the period of CPET were evaluated in the MI patients with diabetes. The patients were followed up for major adverse cardiovascular events (MACE) (admission due to chest pain, re-revascularization, re-infarction and all-cause death) within 24 months after PCI. Multivariate logistic regression analyses were conducted to examine influencing factors for exercise tolerance. Results: The ratio of diabetes, type C lesions in the AEC group were higher than those in the NEC group (diabetes: 37.5% vs. 17.5%; type C lesions: 69.4% vs. 42.5%, respectively, all P<0.05). The left ventricular ejection fraction (LVEF) in patients in the AEC group was lower than that in the NEC group [(60.6±10.0)% vs. (65.0±8.2)%, P=0.019]. Multivariate logistic regression analyses showed that history of diabetes and history of type C lesions were the independent risk factors for the declined exercise capacity in the MI patients after PCI revascularization (OR=3.14, 95%CI 1.167-8.362, P=0.023; OR=3.32, 95%CI 1.444-7.621, P<0.01). Among the MI patients with diabetes, the duration of diabetes in the AEC group was significantly longer than that in the NEC group[(7.7±3.6)years vs. (5.0±2.4)years] and the proportions of subjects reaching target levels of fasting plasma glucose (40.7% vs. 57.1%) and glycosylated hemoglobin A1c(HbA1c) (55.6% vs. 71.4%) in this group were significantly lower than those in the NEC group (all P<0.05). A multivariate logistic regression analysis showed that reaching HbA1c target was an independent predictor of improved exercise tolerance in MI patients with diabetes who received PCI (OR=2.518, 95%CI 1.395-7.022, P=0.021). No significant differences were observed in incidence of admission due to chest pain, re-revascularization and re-infarction between the two groups within 24 months after PCI between the groups. Conclusions Diabetes and type C lesions are independent risk factors of declined exercise capacity in patients with first myocardial infarction who received revascularization in acute state. Reaching target HbA1c is independent factor of improved exercise capacity in patients with myocardial infarction and diabetes.