5.14 Obesity-Related Adjunctive Systo-Diastolic Ventricular Dysfunction in Patients with Hypertension: Echocardiographic Evaluation with Tissue Velocity and Strain Imaging

Abstract

Introduction. Obesity is an independent risk factor for the development of heart failure, even after accounting for other co-morbid conditions that cluster with it, such as above all hypertension. In this context, application of innovative echocardiographic techniques like tissue Doppler imaging (TDI) and strain imaging (SI) has been largely extended, in order to improve the assessment of systodiastolic ventricular function. Aim. To evaluate left ventricular morphologic and functional parameters with traditional echocardiography, TDI and SI in patients with hypertension compared to patients with hypertension and obesity. Methods. We evaluated 190 patients, mean age 56±11 years, 94 males, affected by treated essential hypertension and divided according to their body mass index (BMI) in Group 1 (BMI <30, n=96 hypertensive patients without obesity) and Group 2 (BMI ≥30, n=94 hypertensive patients with obesity). The 2 groups were matched in age, sex, heart rate, systo-diastolic blood pressure, antihypertensive drug therapy; apart from familiar history of cardiovascular disease, no other risk factors nor systemic diseases were represented in the study population. All patients were evaluated with traditional echocardiography, TDI and SI: for all patients mean values of peak systolic, early diastolic and late diastolic velocities of the septal, lateral, inferior and anterior region of the mitral annulus were calculated; peak strain values of basal interventricular septum were also obtained. Results. BMI was 26.9±4.6 in Group 1 and 35.7±5.2 in Group 2 (p<0.001). Traditional echocardiographic parameters showed no significant differences between the 2 groups, with the only exception of left ventricular mass; however, left ventricular mass index was similar in both groups. About TDI parameters, mean values of peak systolic and early diastolic velocities were significantly decreased in Group 2 (respectively 5.55±.4 cm/s vs. 6.46 ±1.3 cm/s, p<0.01; 5.69 ±1.5 cm/s vs. 6.42±1.4 cm/s, p<0.05); mean values of peak late diastolic velocities were increased without reaching statistical significance in Group 2 (7.2 4±1.9 cm/s vs. 6.80 ±2.3 cm/s, p=0.08). About SI parameters, peak strain values of basal interventricular septum were also significantly decreased in Group 2 (18.24±3.2 vs. 21.1 2±2.9, p<0.01). Conclusions. In hypertensive patients obesity is related to a higher level of systo-diastolic left ventricular dysfunction. In our study, TDI and SI revealed and highlighted that even if obesity tends to cluster with hypertension, its presence is related to a significant worsening of the left ventricular dysfunction observed in hypertensive patients.