The effectiveness and safety of Chinese Patent Medicines based on syndrome differentiation in patients following percutaneous coronary intervention due to acute coronary syndrome (CPM trial): A nationwide Cohort Study

Background: The incidence of cardiovascular events remains not unusual in patients following percutaneous coronary intervention (PCI) due to acute coronary syndrome (ACS). Chinese patent medicine (CPM) therapy based on syndrome differentiation in addition to conventional medicine (CM) had been expected to further reduce the risk of cardiovascular events. Purpose: To assess the effectiveness and safety of CPM based on syndrome differentiation in patients following PCI due to ACS. Study design: Nationwide prospective cohort study. Methods: CPM study was conducted in 40 centers in mainland China. Patients following PCI due to ACS entered to syndrome differentiation-based CPM (SDCPM) or CM group according to whether they received CPM or not. The CPM comprised Guanxin Danshen dripping pills, Qishen Yiqi dripping pills, or Danlou tablets, and was used correspondingly with the syndrome differentiation of traditional Chinese medicine. The follow-up time was 36 months. The primary endpoint was composed of cardiac death, non-fatal myocardial infarction and urgent revascularization. The secondary endpoint included rehospitalization due to ACS, heart failure, stroke, other thrombotic events. Seattle Angina Questionnaire (SAQ) was used to evaluate quality of life. Results: Between February 2012 and December 2018, ascertainment of the primary endpoint was completed in 2,724 patients of follow-up. 1,380 patients were in SDCPM group. At a median follow-up of 541 (interquartile range 513 - 564) days, the primary endpoint occurred in 126 (8.61%) patients in SDCPM group and 167 (11.62%) patients in CM group (adjusted hazard ratio [HR] = 0.70; [95% confidence interval [CI] 0.55 - 0.89]; p = 0.003). The secondary endpoint occurred in 144 (9.84%) patients in SDCPM group and 197 (13.71%) patients in CM group (adjusted HR = 0.66; [95% CI 0.53 - 0.82]; p < 0.001). The SAQ score in SDCPM group was higher than CM group (366.78 +/- 70.19 vs 356.43 +/- 73.80, p < 0.001). There were no significant differences of adverse events between two groups. Conclusion: In patients following PCI due to ACS, SDCPM in addition to CM treatment reduced the primary and secondary endpoints, as well as improved the quality of life without adverse events.