[Hemodynamics of massive obesity].
Congestive heart failure is a frequent complication of massive obesity and a major cause of death. Prior to the cardiac decompensation stage, infraclinical haemodynamic disturbances can be observed in obese subjects with normal blood pressure: the cardiac output and cardiac index increase, due to a rise in systolic ejection volume, the total peripheral resistance falls and the intravascular volume augments. Cardiac adjustment takes place in the form of excentric left ventricular hypertrophy. Ventricular extrasystoles, often associated with this hypertrophy, might be the cause of sudden death in some obese patients. Arterial hypertension is about 3 times more frequent in obese subjects than in subjects of normal weight, and even more frequent in those with massive obesity. To the high preload due to obesity hypertension adds an increased after-load. This results in augmentation of the mass and work of the left ventricle with progressive alteration of its function. The incidence of coronary disease is increased in obese subjects, notably those with abnormal adiposity. Finally, the return circulation is very often perturbed, notably in gynecoid obesity: there is venous insufficiency with a higher risk for thromboembolism, and lymphatic insufficiency or capillary permeability disorders. A low-calorie diet and a physical rehabilitation of sedentary obese subjects facilitate weight reduction and at the same time tend to correct the associated metabolic disturbances; they reduce blood pressure and also seem to reduce the left ventricular hypertrophy.
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Hôpital Jean Verdier, service d'endocrinologie-diabétologie-nutrition, Bondy.
D002318:Cardiovascular Diseases / Q000209:etiology*; D006439:Hemodynamics; D006801:Humans; D009767:Obesity, Morbid / Q000503:physiopathology*
Hémodynamique de l'obésité massive.