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

•The Tongxin formula significantly reduces the incidence of major adverse cardiovascular events in patients with acute coronary syndromes after coronary stenting, demonstrating a notable improvement in patient outcomes when added to optimal medical therapy.•Patients receiving the Tongxin formula exhibit less lumen loss within stented segments and at both proximal and distal ends, indicating its efficacy in preventing restenosis post-percutaneous coronary intervention over a 6-month period.•The study highlights the Tongxin formula's ability to improve clinical symptoms and quality of life, as evidenced by higher Seattle angina scores, without adversely affecting liver and renal function or coagulation indexes, underscoring its safety and therapeutic potential in post-PCI management. 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. 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. 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-co