Amino-terminal B-natriuretic peptide levels and postablation recurrence in hypertensive patients with paroxysmal atrial fibrillation.

BACKGROUND: Amino-terminal B-type natriuretic peptide (NT-proBNP) has been shown to predict postablation recurrences of atrial fibrillation (AF); however, given the associations of natriuretic peptides with various cardiovascular parameters potentially related to AF, whether the observed association with recurrence is truly an independent one is not clear. OBJECTIVE: The purpose of this analysis was to assess the association of NT-proBNP levels with AF recurrence after radiofrequency ablation. METHODS: This was a post hoc analysis of a prospective study of 296 hypertensive patients with symptomatic paroxysmal AF and no history of heart failure who were scheduled to undergo pulmonary vein isolation. NT-proBNP was measured at baseline, and patients were followed for a median of 13.7 months. RESULTS: NT-proBNP levels at baseline were higher in patients with recurrence (269 pg/mL [199-361 pg/mL]) vs those who remained arrhythmia-free (188 pg/mL [146-320 pg/mL], P<.001). In a univariate Cox regression model, each higher quartile of NT-proBNP corresponded to a 47% (95% confidence interval 21.5%-77.9%) increase in the risk of recurrence. However, when baseline clinical AF burden, in terms of the number of clinical AF episodes in the previous year, was added to the model, the association of NT-proBNP lost its significance (adjusted hazard ratio 1.22, 95% confidence interval 0.94-1.57). CONCLUSION: This is the largest series to date showing that NT-proBNP is a univariate predictor of postablation AF recurrence. However, it seems that adjustment for other covariates, including the number of AF episodes within the previous year, renders this association nonsignificant.