A group of normotensive obese subjects (group A), a group of hypertensive obese subjects (group B) and a group of control subjects (group C) were submitted to radionuclide ventriculography using 99mTc to investigate cardiac function and haemodynamic situation in the presence of an increased preload (group A), preload and afterload (group B). Results show a significant reduction in ejection fraction and systolic blood pressure/end systolic volume in group A. Group B shows better cardiac function probably for the presence of cardiac concentric hypertrophy. Left ventricle work either in a minute and for each beat is greatest in patients of group B. Thus the simultaneous presence of obesity and hypertension can cause a worse prognosis in such patients for cardiac ischaemia and/or sudden death.