Abstract 19087: Left Atrial Appendage Thrombus is not an Independent Predictor of Mortality in Patients With Atrial Fibrillation
Background: Atrial fibrillation (AF) is an independent predictor of mortality. It is hypothesized that an increase in mortality in patients with AF is due to the presence of a thrombus in the left atrial appendage (LAA). However, data supporting this is limited. The purpose of this study was to determine if the presence of a LAA thrombus in patients with AF is associated with an increase in all cause mortality and whether or not it is an independent predictor of mortality.
Methods: A total of 2918 patients with AF underwent trans-esophageal echocardiography (TEE) prior to cardioversion at a tertiary care hospital from 1999 to 2012. Subjects with history of a LAA ligation or resection, rheumatic heart disease, cardiac transplant, watchman device, and prosthetic valve were excluded. Patients who had multiple TEE studies, only the first TEE study was included. Subjects were then classified based on presence or absence of a LAA thrombus and followed for all cause mortality.
Results: Of the 1900 patients included, 146 (7.7%) were found to have a LAA thrombus. Kaplan Meier mortality analysis showed a significantly higher all cause mortality rate in patients with a LAA thrombus (n=67, 45.9%) compared to those without a LAA thrombus (n=458, 26.1%) (p<0.0001). Multivariate analysis confirmed that a LAA thrombus is not predictive of independent mortality (hazard ratio (HR), 1.079; 95% confidence interval (CI), 0.823-1.415; p=0.58). The greater mortality is attributable to age (p<0.001), congestive heart failure (p<0.001), stroke (p<0.001), diabetes mellitus (p=0.0015), vascular disease (p=0.0119), ischemic cardiomyopathy (p=0.0218), pulmonary disease (p<0.001), dyslipidemia (p=0.0178), and chronic kidney disease (p<0.001). Data was reassessed considering the possibility that thrombus size was the cause of this increase in mortality; however, that was also shown not to be an independent predictor of mortality (HR, 1.085; 95% CI, 0.9-1.308; p=0.393).
Conclusion: In a large cohort of patients with AF undergoing TEE prior to cardioversion, we concluded that the presence of a thrombus in the LAA was associated with a higher degree of mortality. However, after adjusting for coexisting conditions it was found not to be an independent predictor of mortality.
Author Disclosures: G.S. Johal: None. A.H. Qazi: None. P. Reddy: None. J.A. House: None. M.L. Main: None.
- © 2015 by American Heart Association, Inc.