Abstract TP423: Predictors of Elevated P Wave Terminal Force and NT-proBNP Differ in the ARCADIA Trial

Abstract

Background: Elevated P-wave terminal force velocity in ECG lead V1 (PTFV1) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are both associated with an increased risk of ischemic stroke and atrial fibrillation and are thought to be markers of an underlying atrial cardiopathy (AC). These AC markers are being used as entry criteria in the ARCADIA trial, testing standard of care aspirin vs. apixaban for secondary stroke prevention. Methods: We used baseline data from patients with embolic stroke of undetermined source (ESUS) who consented for AC screening in the ARCADIA trial to develope multivariable relative risk regression models separately predicting the dichotomous outcomes of PTFV1 > 5000 μV*ms and NT-proBNP > 250 pg/mL. Age, race and gender were forced into both final models. Results: Overall 924 patients were consented with a mean age of 66 years (SD +/- ) and demographics including 45% women, 78% white and 8% Hispanic. 113 patients met the elevated PTFV1 criteria and 162 patients met the elevated NT-proBNP criteria. Significant predictors in each model are shown in the Table. Black race was a significant predictor of elevated PTFV1 but not NT-proBNP. Increasing hemoglobin showed a differentially significant association with both AC markers, increasing PTFV1 probability but decreasing probability of NT-proBNP. Increasing age was significantly associated with greater risk of elevated NT-proBNP but not for PTFV1. A history of other vascular disease was not associated with either AC marker. Conclusions: Amongst the ESUS patients being screened for AC in the ARCADIA trial, varying demographic and baseline biomarkers are differentially associated with the separate markers of AC. These preliminary findings suggest potential pathophysiologic heterogeneity converging on AC, and underscore the importance of careful subgroup analyses as prespecified in the ARCADIA statistical plan.