Clinical Electrophysiology -> Atrial Fibrillation & Atrial Flutter: -> Physiology D-PO03 - Poster Session III (ID 48) Poster

D-PO03-224 - Left Atrial Appendage Size And Emptying Velocity Predict Brain Natriuretic Peptide Elevations In Atrial Fibrillation (ID 370)

 J. Cook: Nothing relevant to disclose.


Background: Atrial fibrillation (AF) is a major cause of ischemic strokes worldwide with thrombus formation in the left atrial appendage (LAA) being a major mechanism. While elevations in brain natriuretic peptide (BNP) are associated with AF and stroke risk, the mechanism for BNP elevations in AF is poorly understood.
Objective: Understand the mechanism for BNP elevations in atrial fibrillation.
Methods: BNP and left atrial pressure (LAP) were measured at the time of LAA occlusion in 132 sequential patients at Vanderbilt University Medical Center. Factors known to impact the BNP (LAA-emptying velocity, left ventricular ejection fraction, renal function, BMI), structural features of the LAA (morphology, depth, ostial diameter), and LAP were considered as covariates. We fit proportional odds model to evaluate the association between BNP and risk factors, adjusting for covariates. Continuous variables were used except for appendage morphology and rhythm at time of procedure.
Results: Patients had a median age of 75 years, BMI of 28.3 kg/m2, and LVEF of 55%. The median eGFR was 57 mL/min/1.73m2 with a CHADS2-VASC score of 4. A history of cerebral vascular accident was present in 26% and OSA in 22%. In regression analysis, LAA emptying velocity had the strongest impact association with BNP levels (OR 0.19 [0.1, 0.38], p<0.001). Appendage size (ostial diameter and depth), but not morphology, also demonstrated association with BNP. See “Table 1.”
Conclusion: Larger LAA size and lower LAA emptying velocity are associated with increased BNP levels. BNP elevations in patients with AF may indicate increased LAA size or LAA dysfunction potentially predicting a higher risk for stroke.