Abstract
BACKGROUND: Timely percutaneous coronary intervention (PCI) is crucial for restoring myocardial blood supply in ST-segment elevation myocardial infarction (STEMI) patients, with the first 72 h being a critical period for early ventricular remodelling. The association between heart rate trajectories within this period and after hospital discharge outcomes in STEMI patients post-PCI remains unclear. METHODS: We conducted a retrospective study involving STEMI patients who underwent successful PCI at three tertiary hospitals in Zhejiang Province, China. Heart rate data were collected every 8 h post-PCI through nursing records, along with intraoperative findings and biochemical markers. Using trajectory modelling, we identified heart rate patterns at 24, 48 and 72 h post-PCI, determined the optimal number of trajectory groups using Akaike information criterion (AIC) and Bayesian information criterion (BIC) criteria, and performed a minimum 3-month follow-up. Cox regression analysed the association between early heart rate trajectories and major adverse cardiovascular events (MACEs) post-discharge. The prognostic value of trajectory models was assessed using the area under the curve (AUC). RESULTS: A total of 1257 patients were included, with an average follow-up duration of 28.72 ± 21.14 months and a mean age of 60.42 ± 14.19 years; 1013 (80.59%) were male. Growth mixture modelling identified four distinct heart rate trajectory groups at 24, 48 and 72 h post-PCI. Higher heart rate trajectories with rates greater than 80 bpm were strongly associated with MACEs, and the 72-hour heart rate trajectory showed a predictive value for MACEs (AUC = 0.745, 95% CI: 0.709-0.781). CONCLUSIONS: Elevated heart rate trajectories exceeding 80 bpm within 72 h after PCI are associated with an increased risk of MACEs post-discharge. Heart rate management should be further emphasized in post-PCI STEMI patients.