Abstract
BACKGROUND AND AIMS: Arrhythmias and major adverse cardiac events remain significant complications following ST-segment elevation myocardial infarction (STEMI). Shenfu injection, a traditional Chinese medicine formulation, has shown cardioprotective effects in preclinical studies. This trial is aimed at investigating whether Shenfu injection as an adjunctive therapy to standard treatment could reduce arrhythmias and improve clinical outcomes in patients with STEMI undergoing percutaneous coronary intervention (PCI). METHODS: A single-center, prospective, randomized, controlled trial was conducted at Shanghai Ninth People's Hospital among 245 patients with STEMI undergoing PCI. Participants were randomized to receive either standard therapy plus Shenfu injection (50 mL, administered intravenously twice daily for five consecutive days) (n = 123) or standard therapy alone (n = 122). The primary endpoint was the incidence of in-hospital arrhythmias. Secondary endpoints included major adverse cardiac events (MACEs) during the 12-month follow-up period and cardiac magnetic resonance imaging parameters. RESULTS: A total of 245 patients underwent randomization (123 assigned to Shenfu injection group and 122 assigned to control group). During hospitalization, patients assigned to Shenfu injection had a significantly lower incidence of arrhythmias compared with the control group (24.4% vs. 38.5%, p = 0.017), with the most pronounced effect on frequent ventricular premature contractions (7.3% vs. 15.5%, p = 0.042). After adjustment for key baseline covariates including age, coronary artery disease extent, myocardial injury markers (CK-MB max and TNI max), left ventricular ejection fraction, B-type natriuretic peptide, door-to-balloon time, hypertension, and diabetes mellitus, Shenfu injection remained independently associated with reduced risk of in-hospital arrhythmias (adjusted OR 0.454, 95% CI: 0.249-0.827, p = 0.010). Cardiac magnetic resonance imaging performed in 174 patients revealed significantly smaller infarct size (16.1 ± 9.1 vs. 20.8 ± 13.1 g, p = 0.007) and lower incidence of microvascular obstruction (45.0% vs. 65.0%, p = 0.008) in the Shenfu group, with both parameters showing significant positive correlations with arrhythmia occurrence. During the 12-month follow-up, patients receiving Shenfu injection had a higher event-free rate from MACEs compared with the control group (12-month Kaplan-Meier event-free rate estimates, 84.6% vs. 73.0%, respectively; p = 0.028). CONCLUSIONS: Treatment with Shenfu injection as an adjunctive therapy to standard treatment in patients with STEMI undergoing PCI significantly reduced in-hospital arrhythmias, infarct size, microvascular obstruction, and major adverse cardiac events during a 12-month follow-up period. The independent effect on arrhythmias after comprehensive statistical adjustment and the demonstrated correlation between reduced myocardial damage and arrhythmia prevention suggest the potential therapeutic value of Shenfu injection in improving both short-term and long-term outcomes in STEMI patients. TRIAL REGISTRATION: Chinese Clinical Trial Registry Identifier: ChiCTR2200066918.