Percutaneous coronary intervention for poor coronary microcirculation reperfusion of patients with stable angina pectoris.

Percutaneous coronary intervention (PCI) has been extensively applied to repair the forward flow of diseased coronary artery and can achieve significant curative results. However, some patients with acute myocardial infarction (AMI) develop non-perfusion or poor perfusion of cardiac muscle tissue after PCI, which increases the incidence of cardiovascular events and the death rate. PCI can dredge narrowed or infarct-related artery (IRA) and thus induce full reperfusion of ischemic myocardium. It is found in practice that some cases of AMI still have no perfusion or poor perfusion in myocardial tissue even though coronary angiography suggests opened coronary artery after PCI, which increases the incidence of vascular events and mortality. Therefore, to explore the detailed mechanism of PCI in treating coronary microcirculation of patients with stable angina pectoris, we selected 140 patients with stable angina pectoris for PCI, observing the index of microcirculatory resistance (IMR) of descending branch and changes of myocardial injury markers and left ventricular systolic function, and made a subgroup analysis based on the correlation between clinical indexes, IMR and other variables of diabetic and non-diabetic patients, PCI-related and non-PCI-related myocardial infarction patients. The results suggest that IMR of anterior descending branch after PCI was higher compared to that before PCI, and the difference was significant (P less than 0.05); creatine kinase-MB (CK-MB), myohemoglobin and high sensitive troponin T were all increased after PCI, and the difference was also significant (P less than 0.05); brain natriuretic peptide (BNP) level became higher after PCI, with significant difference (P less than 0.05); left ventricular ejection fraction (LVEF) declined after PCI, and the difference before and after PCI was statistically significant (P less than 0.05). Moreover, subgroup analysis results of the three groups all demonstrated statistically significant differences. PCI can effectively increase microcirculatory resistance of patients with stable angina pectoris, especially those who develop both stable angina pectoris and diabetes. Patients with higher microcirculatory resistance before PCI are more likely to develop PCI-related myocardial infarction after PCI.