High left atrial pressures are associated with advanced electroanatomical remodeling of left atrium and independent predictors for clinical recurrence of atrial fibrillation after catheter ablation.

BACKGROUND: The clinical significance of left atrial pressure (LAP) has not yet been clearly elucidated in patients with atrial fibrillation (AF).

OBJECTIVE: To explore the effects of elevated LAP on pathophysiology and clinical outcome after radiofrequency catheter ablation in patients with AF.

METHODS: We measured LAP during both sinus rhythm (SR) and AF in 454 patients 348 (76.7%) men; mean age 58 ± 11 years; 326(71.8%) paroxysmal AF) who underwent radiofrequency catheter ablation and compared LAP at v wave (LAPpeak) and LAP at y descent (LAPnadir) by using imaging (echocardiography and computed tomography), electrophysiologic mapping (NavX), and clinical data. In 280 (61.7%) patients, pulmonary vein (PV) diastolic flow velocity was measured during SR by transesophageal echocardiography.

RESULTS: Patients with LAPpeak(SR) ≥19 mm Hg had greater left atrial (LA) dimension (P < .001), LA volume index (P = .003), and E/Em (mitral annular septal area [peak diastolic velocity]; P = .001) but reduced LA voltage (P < .001) and mitral annular septal area (peak systolic velocity; P = .006) compared with patients with LAPpeak(SR) <19 mm Hg. High LAPpeak(SR) was independently associated with anterior LA volume (linear regression coefficient [B] = 0.381; 95% confidence interval [CI] 0.169-0.593; P < .001) and low LA voltage (B = -0.022; 95% CI -0.030 to -0.013; P < .001). PV diastolic flow velocity (B = 0.161; 95% CI 0.083-0.239; P < .001) and E/Em (B = 0.430; 95% CI 0.096-0.763; P = .012) were independent, noninvasive parameters associated with high LApeak(SR). During 13.1 ± 6.0 months of follow-up, high LAPpeak(SR) was an independent predictor for clinical recurrence of AF (hazard ratio 1.887; 95% CI 1.063-3.350; P = .028).

CONCLUSION: Elevated LAP was closely associated with electroanatomical remodeling of the LA and was an independent predictor for recurrence after AF ablation. PV diastolic flow velocity and E/Em can be used as a noninvasive parameter predicting high LAPpeak(SR) in patients with AF.