Additive Predictive Value of Left Ventricular End-Diastolic Volume Index to the Development of Persistent Atrial Fibrillation in Nonobstructive Hypertrophic Cardiomyopathy

Introduction: The aim of this study was to evaluate the association between left ventricular end-diastolic volume index (LVEDVi) and the risk of persistent or long-standing persistent atrial fibrillation (perAF) in nonobstructive hypertrophic cardiomyopathy (NOHCM) patients. Methods: Forty-nine NOHCM patients with perAF were selected as the case group (NOHCMAF group). A control group comprised 98 NOHCM patients without atrial fibrillation (AF) history. Results: Compared to the control group, patients in the NOHCMAF group were associated with higher CHA₂DS₂-VASc score (3.0 ± 1.7 vs. 2.2 ± 1.1, p = 0.003), higher grade of diastolic dysfunction (II/III) (43.3% vs. 19.4%, p < 0.001). Meanwhile, they were associated with a larger left atrial diameter (LAD) (46.8 ± 4.7 vs. 39.3 ± 4.5 mm, p < 0.001) and a smaller LVEDVi (63.88 ± 15.07 mL/m² vs. 78.86 ± 12.26 mL/m², p < 0.001). Multivariate logistic analysis indicated the independent predictive factor of LVEDVi (odds ratio: 0.908, confidence interval: 0.861–0.957, p < 0.001). The multivariable models revealed the additive discrimination for perAF by the LVEDVi with a higher C-statistic of 0.945 in combination with age at diagnosis and LAD. The LVEDVi cutoff for predicting perAF was 71 mL/m². Conclusions: LVEDVi was independently associated with the occurrence of perAF in NOHCM patients, demonstrating an incremental value compared to conventional LA parameters. Increased cardiac rhythm monitoring is recommended for patients with LVEDVi ≤71 mL/m².