الفهرس | Only 14 pages are availabe for public view |
Abstract SUMMARY Obesity is a chronic medical problem, with dramatically rising trends in its prevalence worldwide, to an extent that it is now recognized as a global epidemic. It is associated with multiple metabolic disturbances leading to increased morbidity and mortality for cardiovascular diseases. Diabetes mellitus, hypertension and hyperlipidemia are among the major causes of obesity-related cardiac disease. Conventional noninvasive imaging modalities are often suboptimal for detailed evaluation of cardiac structures and for detection of subtle functional changes associated with obesity. Newer echocardiographic techniques such as tissue Doppler imaging (TDI) and TDI-derived techniques; strain imaging/strain rate imaging (SRI), could better characterize these possible cardiac abnormalities associated with obesity. In particular, SRI is relatively load independent, and this characteristic is very relevant in the obese population, in which a cardiac volume overload exists. The study was conducted on 45 selected obese patients with obesity defined as BMI ≥ 30, presented to Obesity outpatient clinic in Menoufia University Hospital from September 2012 to February 2013 and 20 age and sex comparable healthy control group with BMI < 30. Patients were enrolled in the study after their informed consent, and approval of ethics committee of Menoufia University Hospitals was obtained. Subjects with congestive heart failure, history of coronary artery disease, cardiomyopathies (hypertrophic, dilated & restrictive), pericardial diseases, hypertension, diabetes mellitus, chest disease (COPD, IPF), thyroid disease, renal diseases, hepatic diseases, pregnancy in females, significant valvular lesion and poor image quality on echocardiography were excluded from the study. All patients were subjected to: 1. Full history taking. 2. Thorough physical examination. 3. 12-lead resting electrocardiogram. 4. Each subject’s height was determined while subject standing without shoes and weight was determined by using a mechanical scale. 5. The body mass index (BMI) was calculated as weight in kilograms divided by the square of height in meters. 6. The waist circumference was measured at the part of the trunk located midway between the lower costal margin, and the iliac crest at the end of expiration while the person is standing with feet about 25–30 cm apart. 7. Standard transthoracic echocardiogram (TTE). 8. Left ventricular longitudinal strain and strain rate imaging. Data collected from the study population were statistically studied showing that obese subjects had significantly increased left atrial diameter, aortic diameter, septal wall thickness, left ventricular posterior wall thickness and LV mass. On the contrary, there was no significant difference between obese patients and control subjects regarding left ventricular diameter in diastole and systole, ejection fraction, fractional shortening, left ventricular mass index and mitral inflow velocity indices (E, A and E/A ratio). Analysis of Left ventricular two dimensional longitudinal strain and strain rate parameters of different LV walls shows significant decrease in global LV longitudinal strain in almost all walls of the LV in obese patients with more significant decrease in class III obesity. The early diastolic wave (E) measured by strain rate was significantly lower in almost all walls of LV in obese patients with more significant decrease in class III obesity, conversely the peak systolic wave (S) measured by strain rate was decreased only in the lateral wall of the LV of obese patients. The late diastolic wave (A) measured by strain rate wasn’t affected in any class of obesity and its values was similar in obese and control subjects. |