P1580Left atrial volume index predicts improvement in renal function after catheter ablation of atrial fibrillation

Abstract

Abstract Background Atrial fibrillation (AF) increased the risk of development of kidney disease. The elimination of AF by catheter ablation is associated with improvement in renal function. However, the mechanism of cardio-renal interaction in AF has not been fully elucidated. Purpose We tested the hypothesis that left atrial volume index (LAVI), which is a marker of left atrial mechanical reserve, predicts improvement in renal function after restoring sinus rhythm with catheter ablation of AF. Methods We analyzed consecutive patients who underwent catheter ablation of AF from January 2012 to October 2018 and had completed follow-up more than 3 months after catheter ablation. Exclusion criteria were need for hemodialysis and acute hospitalization. Estimated glomerular filtration rate (eGFR) was assessed on admission and at the end of follow-up periods after catheter ablation and the difference was defined as ΔeGFR. Left atrial volume index was derived using the biplane area-length method. Results A total of 159 AF patients (paroxysmal 112 [70%], persistent 47 [30%]) were included in this study. The mean age was 65±11 years and 74% were male. During the mean follow-up period of 7.9±3.2 months, 105 patients (66%) were free from atrial tachyarrhythmias and 54 (34%) experienced the recurrence. Baseline eGFR and LAVI were not significantly different between the non-recurrence group and the recurrence group (71.0±17.4 and 75.1±22.8 mL/min/1.73m2; p=0.24, 35.7±12.5 and 37.9±15.0 ml/m2; p=0.34). ΔeGFR in the non-recurrence group was significantly greater compared with the recurrence group (+1.5±1.0 versus −4.3±1.4 mL/min/1.73m2; p=0.001). Baseline LAVI was negatively correlated with ΔeGFR in the non-recurrence group (r=−0.3; p=0.002; Figure), but not in the recurrence group (p=0.1). Multiple regression analysis in the non-recurrence group identified baseline LAVI (β=−0.35, p<0.001), baseline age (β=−0.31, p<0.001) and baseline eGFR (β=−0.59, p<0.001) as independent predictors for eGFR improvement after catheter ablation. In the patients with LAVI <34 ml/m2, age <70 years and eGFR <90 mL/min/1.73m2, the mean ΔeGFR was +6.3±1.9 mL/min/1.73m2. Figure 1 Conclusions LAVI, a marker of left atrial mechanical reserve, was an independent predictor of improvement in renal function after restoring sinus rhythm with catheter ablation of AF. This observation suggests that AF-related deterioration of renal function is due at least in part to impaired atrial mechanical function.