Efficacy and safety of Tongxin formula after stent implantation for acute coronary syndrome: a multicenter, double-blind, placebo-controlled randomized trial

Objective The aim of this study is to comprehensively evaluate both the efficacy and safety profile of integrating the Tongxin formula with optimal medical therapy (OMT) for patients experiencing acute coronary syndromes subsequent to coronary stenting, over the course of one year. Methods We enrolled 150 patients diagnosed with acute coronary syndromes who had received stent placement within one month and exhibited a TCM syndrome characterized by Qi deficiency and blood stasis. This group comprised patients with unstable angina, non-ST-segment elevation myocardial infarction, and ST-segment elevation myocardial infarction. The participants were divided equally, allocating 75 to the Tongxin formula group and 75 to a placebo-controlled group. After undergoing percutaneous coronary intervention (PCI) surgery, both groups received conventional Western medical care, including dual antiplatelet therapy and lipid-lowering medications. The placebo-controlled group received a placebo, while the Tongxin formula group were administered Tongxin formula granules orally. Both study cohorts were monitored for a duration of 6 months. The primary endpoints included the occurrence of major adverse cardiovascular events and the rate of lumen diameter reduction post-treatment in both groups, with the Seattle Angina Scale serving as a secondary assessment tool. Safety evaluations encompassed the measurement of liver and kidney function, coagulation parameters, and other relevant indicators. Results The rate of adverse cardiovascular events in the placebo-controlled group was 42.46% within a year of surgery, whereas it was 16.90% in the Tongxin formula group (P < 0.05). Comparing the Tongxin formula group to the placebo-controlled group, there was a decrease in the frequency of unstable angina and readmission due to cardiovascular events (P < 0.05). Coronary angiography performed 6 months after surgery revealed that the Tongxin formula group had considerably less lumen loss than the placebo-controlled group in a number of segments, including the entire segment, within the stent, at the proximal end, and at the distal end (P < 0.05). Six months after surgery, the Seattle angina score was higher in the Tongxin formula group than in the placebo-controlled group (P < 0.05). There were no significant changes in indicators such as liver and renal function as well as coagulation indexes in both groups within the first 12 months after surgery (P > 0.05). Conclusion Tongxin formula has been shown to lower the occurrence of major adverse cardiovascular events, minimize narrowing of blood vessel lumen, enhance clinical symptoms, and enhance the quality of life of patients following PCI surgery, all while maintaining a good safety profile.