Association between Chinese herbal medicine and the composite outcome of repeat revascularization and in-stent restenosis in patients with chronic coronary syndrome undergoing percutaneous coronary intervention: a prospective cohort study

To evaluate the association between adjunctive Chinese herbal medicine (CHM) and post-percutaneous coronary intervention (PCI) adverse cardiovascular events in patients with chronic coronary syndrome (CCS), and to identify subgroups that may derive greater benefit from integrative therapy.

This study included 2274 patients with CCS after PCI: 1155 patients in the guideline-directed medical treatment (GDMT) group and 1119 patients in the integrative Chinese and Western medicine (ICWM) group. Exposure was defined as cumulative CHM treatment for > 6 months per year. The primary endpoint was a composite of repeat revascularization and in-stent restenosis (ISR). Kaplan-Meier survival analysis and multivariable Cox regression models were used to assess associations between treatment strategy and study outcomes.

A total of 1054 patients experienced the primary endpoint, including 575 patients (49.80%) in the GDMT group and 479 patients (42.80%) in the ICWM group. Compared with the GDMT group, the ICWM group had lower cumulative incidences of the primary endpoint, repeat revascularization, and ISR (log-rank P < 0.001, P = 0.0018, and P = 0.023, respectively). After full adjustment, ICWM was associated with lower risks of the primary endpoint (adjusted HR = 0.741, 95% CI: 0.654–0.841, P < 0.001), repeat revascularization (adjusted HR = 0.781, 95% CI: 0.686–0.889, P < 0.001), and ISR (adjusted HR = 0.825, 95% CI: 0.686–0.993, P = 0.042). Subgroup analyses suggested a more pronounced association in patients with prior PCI (adjusted HR = 0.59, 95% CI: 0.48–0.73, P < 0.001) and those without multivessel coronary artery disease (adjusted HR = 0.46, 95% CI: 0.32–0.68, P < 0.001).

In this prospective cohort study, adjunctive CHM was associated with lower risks of the composite endpoint of repeat revascularization and ISR, as well as its individual components, in patients with CCS after PCI. The observed association appeared more pronounced in patients with prior PCI and those without multivessel coronary artery disease.