Abstract T P180: Diastolic Dysfunction and Left Atrial Volume Mediates Embolic Stroke in Patients with Atrial Fibrillation
Background: Several risk predictors for stroke in AF patients, specifically the CHADS2 criteria, have been implicated in left ventricular (LV) diastolic dysfunction (DD). It is plausible that DD and subsequent elevation in left ventricular filling pressure (LVFP) mediate stasis within the left atrium leading to thrombus formation and embolic stroke in AF patients. Left atrial volume index (LAVI) is known to correlate with LVFP and AF chronicity. We sought to assess whether LAVI can predict ischemic stroke in patients with AF, independent of clinical risk predictors.
Hypothesis: In AF patients, LAVI is associated with ischemic stroke independent of clinical covariates.
Methods: We conducted a retrospective case-control study with 203 patients. The case group (n=33) was derived from our institution’s stroke database which was used to identify strokes attributed to an embolic mechanism related to AF as adjudicated by expert neurologist. The control group (n=79) was generated of consecutive AF patients without previous history of stroke. The left atrial dimensions were measured and the left atrial volume (LAVI) was calculated. Binary logistic regression analysis was used to explore whether LAVI predicted stroke independently from CHADS2 score.
Results: The mean LAVI in the stroke group was 50.74 s 23.83 in the non-stroke group (p<0.001). Binary logistic regression analysis demonstrated that LAVI was significant as an independent risk factor in addition to the CHADS2 score (OR 1.12, CI: 1.0-1.185 per cc/m2 of volume increment, p<0.001). Subsequently, we developed a novel risk score in which 1 additional point was added to the CHADS2 score for every 5cc increment in the LAVI. The receiver operator characteristics curve analysis showed that the AUC for the novel risk score (LAVI +CHADS2) as a predictor for ischemic stroke to be 0.87 vs 0.74 for the clinical factors alone (p<0.05)
Conclusion: Our preliminary data demonstrates that LAVI is an independent risk predictor for embolic stroke in patients with AF. Integrating LAVI with clinical predictors (CHADS2 score) may enhance our ability in predicting stroke and to allow us to better select patients for anticoagulation therapy.
Author Disclosures: M. Alhaji: None. M. Raju: None. F. Al Darazi: None. A. Kakkar: None. R. Olstein: None. S. Prabhakaran: None. R. Doukky: None.
- © 2014 by American Heart Association, Inc.