Abstract
BACKGROUND: Acute ST-segment elevation myocardial infarction (STEMI) is characterized by a rapid inflammatory response, with mast cells (MCs) playing a significant role. However, the relationship between MC activation and the adverse outcomes remains unclear. This study investigated the association between the MC activation biomarker, tryptase, and major adverse cardiovascular events (MACE). METHODS: This prospective study included patients with STEMI who underwent primary percutaneous coronary intervention (PPCI) at Peking University Third Hospital between July 2020 and July 2023. Tryptase levels were detected from plasma samples collected 6 hours post-PPCI and using ELISA method. All patients were followed up every 6 months, with MACE as the primary endpoint. RESULTS: The study enrolled 514 patients with STEMI who underwent PPCI (mean age: 59.27 ± 13.26 years, 16.93% female). The median follow-up time was 13.28 (10.47-37.61) months, during which 85 patients (16.54%) experienced MACE. Patients in the higher tryptase group had a higher risk of MACE (HR 2.60 [1.68-4.01], P < 0.001). Tryptase was an independent risk factor of MACE (HR 1.56 [1.29-1.88] per 1-unit increase, P < 0.001). Subgroup analysis revealed the prognostic value of tryptase among different age groups, left ventricular ejection levels, and patients with hypertension, hyperlipidemia, smoking and diabetes. The addition of tryptase to the basic model had an incremental effect on the predictive value for MACE (AUC: 0.763 vs 0.702, P = 0.002). CONCLUSION: In this study, elevated tryptase levels, a biomarker of MC activation, were identified as a significant predictor of MACE in STEMI patients undergoing PPCI. TRIAL REGISTRATION: (ClinicalTrials.gov NCT05802667).