Latent transforming growth factor-β binding protein 4 as a biomarker of arrhythmia-induced cardiomyopathy in atrial fibrillation: insights from a high-throughput proteomic analysis

Abstract

The validation cohort included 16 AF patients with LVEF <50% undergoing CA. Pulmonary vein isolation and additional ablation procedures were performed using standard radiofrequency techniques. Blood sampling was performed during CA, and proteomic profiling used SomaScan Version 4.1. At 3 months after CA, AIC classification was performed in patients maintaining SR, defined as an absolute LVEF increase >20 percentage points or normalization to ≥ 50%; others were classified as non-AIC. 4 Rhythm status was confirmed by scheduled 12-lead electrocardiograms and 24 h Holter monitoring. Protein levels were compared using the Wilcoxon rank-sum test. Odds ratios per 1-SD increase in log10-transformed protein concentrations were estimated using Firth’s penalized logistic regression. Because different SomaScan assay versions were used, protein concentrations were not directly compared between cohorts. Each cohort was analysed independently using version-specific normalized data.