Efficacy and safety of Tongxin formula in the treatment of coronary microvascular disease: A randomized, double-blind, placebo-controlled clinical trial study

Objective: The objective of this study was to evaluate the efficacy and safety of Tongxin Formula in the treatment of coronary microvascular disease.

Methods: We conducted a randomized, double-blind, placebo-controlled study simultaneously in two hospitals, consisting of 80 participants. Using a random number table, we assigned patients to the treatment and control groups. Patients in both groups received conventional Western medicine for coronary microvascular disease. In addition, those in the treatment group received Tongxin formula granules, while those in the control group received a placebo. The treatment course for both groups was three months, and the follow-up duration was six months. The primary efficacy indicators were coronary blood flow reserve and cardiovascular adverse events; the secondary efficacy indicators were the traditional Chinese medicine (TCM) syndrome score, the angina symptom score, the Seattle Angina Questionnaire (SAQ) score, left ventricular function, and adverse reactions.

Results: After treatment, patients in the treatment group showed significantly higher variation in the coronary flow reserve (CFR) levels (CFR >2) and improvement of diastolic function (peak filling rate, or PFR >2.5) than those in the control group (P < 0.05). After 6 months of follow-up, the incidence of cardiovascular events in the treatment group was significantly lower than that in the control group (P < 0.05). After 3 months of treatment and 6 months of follow-up, the total effective rates of TCM symptoms and angina symptoms, as well as the total SAQ standard scores, in the treatment group were higher than those in the control group (P < 0.05). There were no serious adverse reactions in either group before or after treatment, and there was no significant change (P > 0.05).

Conclusion: We found that Tongxin Formula combined with conventional Western medicine can significantly improved the level of coronary blood flow reserve, reduced the occurrence of cardiovascular adverse events, improved the clinical symptoms of patients, and enhanced the quality of life of patients with coronary microvascular disease with favorable safety.