Functional studies of left atrium and BNP in patients with paroxysmal atrial fibrillation and the prediction of recurrence after CPVA.

Objective This study was aimed to observe the significance of the left atrium (LA) functional index combined with B-type natriuretic peptide (BNP) level in predicting recurrence in patients with paroxysmal atrial fibrillation (PAF) after circumferential pulmonary vein ablation (CPVA). Real-time three-dimensional echocardiography (RT-3DE) was used to observe the structural and functional changes of LA in patients with PAF after CPVA. BNP is a hemodynamic indicator of myocardial stretching increase in atrial fibrillation (AF) patients. Patients and methods 243 patients with PAF who intended to undergo CPVA were selected in the study, and the following clinical data of the patients were collected. Firstly, the blood BNP levels measured before CPVA. Secondly, the measurements of routine echocardiography before CPVA. RT-3DE was used to obtain the time-volume curve of LA. Then, multivariate logistic regression analysis was used to analyze the factors affecting PAF recurrence after CPVA. Finally, we obtained the receiver operating characteristic (ROC) curve of PAF recurrence predicted by the independent risk factors. Results A total of 233 AF patients with an average age of 63.1 ± 9.3 years (range, 39-75 years; male: female =195: 38) underwent CPVA. 42 patients had AF recurrence (18.0%) during 3-6months follow-up after an operation blanking period of 3 months, BNP in the Recurrence Group was higher than that in Sinus Rhythm Group (p≤0.001). The preoperative left minimum volume index (LAVImin), left atrial volume index before contraction (LAVIpre-a) were higher in Recurrence Group than in Sinus Rhythm Group (p≤0.001). Expansion index, Diastolic emptying index (DEI), Passive emptying index (PEI), Active emptying index (AEI) were lower in the Recurrence Group than in the Sinus Rhythm Group (p≤0.001). Logistic regression analyses showed that BNP and DEI were independent predictors for PAF recurrence (OR=1.004, 95% CI: 1.01-1.07, p=0.001; OR=0.655, 95% CI: 0.57-0.75, p=0.001). The AUC of BNP, DEI and combined index for recurrence of CPVA were higher than LAVImax (p range: 0.001-0.013). Conclusions In patients with PAF treated with CPVA, the impaired DEI of LA reservoir function and increased BNP may be useful predictors of PAF recurrence.