Abstract
BACKGROUND: Diastolic dysfunction can be caused by hypertension or diabetes mellitus, and it is also often found with increasing age. In a given patient, the cause of diastolic dysfunction is therefore not always obvious. We sought to study the interplay of these risk factors for diastolic dysfunction in an outpatient population with a low likelihood of ischemic heart disease. METHODS: Consecutive patients referred for stress echocardiography were included retrospectively. Exclusion criteria included pathological stress response, atrial arrhythmia, left ventricular ejection fraction < 55%, and more than mild valvular disease. Standard diastolic parameters were recorded in all patients. In a subset of patients, mechanistic analysis of early filling was performed using the parameterized diastolic filling (PDF) method. RESULTS: We included 726 patients (median [interquartile range] age 56 (44-65) years, 57% male). The prevalence of diabetes and hypertension was 43 and 49%, respectively. In multiple linear regression modeling, the presence of diabetes, hypertension, sex and increasing age explained a moderate amount of the variance in e' velocities, E/A ratio and E/e' (R(2) = 0.31-0.48, p < 0.001), and a low amount of the variance in left atrial volume index (LAVI) and the PDF parameters (n = 446, R(2) = 0.05-0.17, p < 0.001). Sex was only related to LAVI and E/e' for the conventional parameters (beta - 0.94, p = 0.04, and beta - 0.91, p < 0.001, respectively). CONCLUSIONS: Diabetes, hypertension, increasing age, and to a lesser extent sex, explain a moderate amount of the variance in conventional diastolic parameters related to myocardial tissue velocities and E/A ratio in a healthy outpatient population. The effect of these risk factors was substantially less pronounced on left atrial volume index and the PDF parameters.