A TCM mixture improves the prognosis of heart attacks? If it sounds too good to be true, it probably is!

This study investigated whether Tongxinluo,a traditional Chinese medicine compound that has shown promise in in vitro, animal, and small human studies for myocardial infarction, could improve clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI). The randomized, double-blind, placebo-controlled clinical trial was conducted among patients with STEMI within 24 hours of symptom onset from 124 hospitals in China. Patients were enrolled from May 2019 to December 2020; the last date of follow-up was December 15, 2021.

Patients were randomized 1:1 to receive either Tongxinluo or placebo orally for 12 months. A loading dose of 2.08 g was given after randomization, followed by the maintenance dose of 1.04 g, 3 times a day, in addition to STEMI guideline-directed treatments. The primary end point was 30-day major adverse cardiac and cerebrovascular events (MACCEs), a composite of cardiac death, myocardial reinfarction, emergent coronary revascularization, and stroke. Follow-up for MACCEs occurred every 3 months to 1 year.

Among 3797 patients who were randomized, 3777 (Tongxinluo: 1889 and placebo: 1888; mean age, 61 years; 76.9% male) were included in the primary analysis. Thirty-day MACCEs occurred in 64 patients (3.4%) in the Tongxinluo group vs 99 patients (5.2%) in the control group. Individual components of 30-day MACCEs, including cardiac death, were also significantly lower in the Tongxinluo group than the placebo group. By 1 year, the Tongxinluo group continued to have lower rates of MACCEs and cardiac death. There were no significant differences in other secondary end points including 30-day stroke; major bleeding at 30 days and 1 year; 1-year all-cause mortality; and in-stent thrombosis. More adverse drug reactions occurred in the Tongxinluo group than the placebo group, mainly driven by gastrointestinal symptoms.

The authors concluded that in patients with STEMI, the Chinese patent medicine Tongxinluo, as an adjunctive therapy in addition to STEMI guideline-directed treatments, significantly improved both 30-day and 1-year clinical outcomes. Further research is needed to determine the mechanism of action of Tongxinluo in STEMI.

Tongxinluo is mixture of various active ingredients, including

• ginseng,
• leech,
• scorpion,
• Paeonia lactiflora,
• cicada slough,
• woodlouse bug,
• centipede,
• sandalwood.

With chaotic mixtures of this type, it is impossible to name all the potentially active ingredients, list their actions, or identify the ones that are truly relevant. According to the thinking of TCM proponents, this would also be the wrong way to go about it – such mixtures work as a whole, they would insist.

Tongxinluo is by no means a mixture that has not been studied before.

A previous systematic review of 12 studies found that Tongxinluo capsule is superior to conventional treatment in improving clinical overall response rate and hemorheological indexes and is relatively safe. Due to the deficiencies of the existing studies, more high-quality studies with rigorous design are required for further verification.

A 2022 meta-analysis indicated that the mixture had beneficial effects on the prevention of cardiovascular adverse events, especially in TVR or ISR after coronary revascularization and may possibly lower the incidence of first or recurrent MI and HF within 12 months in patients with CHD, while insufficient sample size implied that these results lacked certain stability. And the effects of TXLC on cardiovascular mortality, cerebrovascular events, and unscheduled readmission for CVDs could not be confirmed due to insufficient cases. Clinical trials with large-sample sizes and extended follow-up time are of interest in the future researches.

A further meta-analysis suggested beneficial effects on reducing the adverse cardiovascular events without compromising safety for CHD patients after PCI on the 6-month course.

Finally, a systematic review of 10 studies found that the remedy is an effective and safe therapy for CHD patients after percutaneous coronary interventions.

So, should we believe the new study with its remarkable findings? On the one hand, the trial seems rigorous and is reported in much detail. On the other hand, the study (as all previous trials of this mixture) originates from China. We know how important TCM is for that country as an export item, and we know how notoriously unreliable Chinese research sadly has become. In view of this, I would like to see an independent replication of this study by an established research group outside China before I recommend Tongxinluo to anyone.

Let’s not forget:

if it sound too good to be true, it probably is!