Abstract MP59: The Association Between Acute Mental Stress and Abnormal P-wave Axis

Abstract

Background: Exposure to psychological stress has been associated with the development of sustained arrhythmias. Acute changes in atrial electrophysiology may serve as intermediate phenotypes for stress-induced arrhythmia. The relationship between atrial electrical changes and stress related changes in heart rate and myocardial ischemia is unknown. We sought to study the effect of altered atrial electrophysiology and stress related rise in HR and myocardial ischemia in females and males. Methods: We examined if acute mental stress was associated with abnormal P-wave axis development in 359 patients (mean age=56 ± 9.9 years; 62% men; 43% white) with stable coronary heart disease and normal baseline P-wave axis (between 0° and 75°) who underwent mental stress testing (speech task). We computed the percentage of patients who had abnormal P-wave axis during stress and recovery. Sex-stratified analyses were performed. A multivariable logistic regression model was used to determine if mental stress ischemia independent predictors of abnormal P-wave axis development. Results: A total of 46 (13%) patients developed abnormal P-wave axis during either stress or recovery (stress: n=43, 12%; recovery: n=12, 3%). A rise in heart rate during mental stress was associated with an increased risk of abnormal P-wave axis development (per 5-unit increase: OR=1.37, 95%CI=1.03, 1.30). Mental stress-induced myocardial ischemia was associated with increased risk of abnormal P-wave axis in women (OR=5.2, 95%CI=1.7, 15.6) and not in men (OR=0.1, 95%CI=0.01, 1.01), p-interaction=0.004). Interactions were not detected for other characteristics. Conclusion: Acute mental stress results in the development of abnormal P-wave axis, and this phenomenon is related to increases in heart rate and, among women, mental stress-induced ischemia. Our data suggest that acute psychological stress can promote adverse transient electrical changes in the atria.