Abstract
OBJECTIVE: To investigate the characteristics of reperfusion arrhythmia during direct percutaneous coronary intervention (PCI) in elderly patients with acute coronary syndrome (ACS) and its impact on prognosis. METHODS: A total of 286 elderly ACS patients admitted to Kweichow Moutai Hospital from January 2019 to February 2023 were included in this retrospective study, with 200 patients used for model development and 86 for validation. Patients were selected based on predefined inclusion and exclusion criteria applied to existing medical records. Data were retrospectively collected, including demographics (age, gender, BMI), clinical history (smoking, alcohol use, hypertension, diabetes), laboratory results (white blood cell count [WBC], hemoglobin [Hb], high-sensitivity C-reactive protein [hs-CRP]), imaging parameters (left atrial diameter [LA], left ventricular end-systolic diameter [LVESD], left ventricular end-diastolic diameter [LVEDD], and left ventricular ejection fraction [LVEF]), and PCI-specific details (time from symptom onset to PCI, pre-infarction angina, and TIMI grade). Statistical analysis was performed to identify risk factors for reperfusion arrhythmia during PCI in elderly ACS patients, and a prediction model was constructed and evaluated for its accuracy. RESULTS: The prevalence of reperfusion arrhythmia in the model group was 74%. Risk factors for post-PCI reperfusion arrhythmia included multivessel disease, presence of pre-infarction angina, preprocedural TIMI grade 0 flow, and shorter time from onset to PCI. A predictive model was developed using the number of vascular lesions, presence of pre-infarction angina, TIMI grade, and time from onset to PCI, and visualized with a nomogram, showing a C-index of 0.841. The calibration curves indicated good agreement between observed and predicted outcomes, while Decision Curve Analysis (DCA) demonstrated a standardized net benefit for risk thresholds above 0.05. Validation with an independent dataset yielded an ROC AUC of 0.837, a Hosmer-Lemeshow goodness-of-fit test χ(2) value of 4.280 (P = 0.747), with a specificity of 90.62% and a sensitivity of 68.18%. CONCLUSION: Elderly ACS patients with multivessel disease, pre-infarction angina, preprocedural TIMI grade 0 flow, and shorter time from symptom onset to PCI are at higher risk of reperfusion arrhythmia during PCI. Early identification and preventive strategies should be implemented to improve patient prognosis.