Predictive value of cardiopulmonary exercise test parameters for atrial fibrillation risk in hypertrophic cardiomyopathy patients

Objective: To investigate the relationship between cardiopulmonary exercise test (CPET) parameters and the occurrence of atrial fibrillation (AF) in patients with hypertrophic cardiomyopathy (HCM).Methods: A retrospective study was conducted on 160 HCM patients hospitalized at Quanzhou First Hospital Affiliated to Fujian Medical University from June 2020 to December 2023.Patients were divided into AF (n=62) and non-AF (n=98) groups.Univariate analysis and logistic regression were used to compare demographic and CPET parameters between groups.A nomogram model was developed to predict AF risk.Results: AF prevalence was 38.75%.Peak Oxygen Uptake per kilogram (Peak VO 2 /kg), Metabolic Equivalent of Task (METs), and Oxygen Uptake at Anaerobic threshold per kilogram (VO 2 /kg AT) were lower in the AF group compared to the non-AF group, while Ventilation to Carbon Dioxide Production Slope (VE/VCO 2 slope) was higher (all P<0.05).Pearson correlation analysis showed a significant negative correlation between Peak VO 2 /kg and New York Heart Association (NYHA) classification (r=-0.231,P=0.003).Logistic regression identified NYHA classification, smoking history, and VE/VCO 2 slope as risk factors for AF, while Peak VO 2 /kg, METs, and VO 2 /kg AT were protective factors (P<0.05).The nomogram model had an area under curve (AUC) of 0.867 (0.808-0.925), demonstrating good calibration and clinical utility.Conclusion: CPET parameters, combined with clinical indicators, can effectively predict AF risk in HCM patients.The nomogram model provides a valuable tool for clinical risk assessment.