Abstract 16854: Arterial Determinants of Time-varying Myocardial Stress in Humans

Background: Myocardial and arterial load are time-varying phenomena. Despite its importance in myocardial biology and function, the arterial properties that determine time-resolved myocardial wall stress have not been directly investigated. Methods: We studied 1215 adults enrolled in the population-based Asklepios study. Time-resolved central pressure and flow were measured with carotid tonometry and Doppler echocardiography. Time-resolved short- and long-axis LV geometry was measured with speckle tracking echocardiography. Using custom-designed software, we computed arterial load, circumferential (CWS) and longitudinal (LWS) wall stress (Regen method) using time-resolved measurements. Results: For any given end-diastolic LV cavity size and wall thickness and any given cardiac output, peak CWS correlated directly with systemic vascular resistance (SVR; Beta weight=1.07; P Conclusions: Different arterial properties have selective effects on time-resolved myocardial wall stress which are not apparent from single-time-point measurements. Women appear to demonstrate less efficient myocardial-ventricular-arterial coupling (higher time-varying stress for a given output) independently of various arterial properties and end-diastolic LV geometry. These observations could provide insight into the well known differential susceptibility of women to heart failure with preserved ejection fraction.