title: Radionuclide angiographic evaluation of left ventricular performance at rest and during exercise in patients with aortic regurgitation.
abstract: Radionuclide angiographic evaluation of LV performance at rest and during exercise in patients with AR have shown that an abnormal EF response to exercise may be observed in asymptomatic patients with normal resting LV function. The EF response to exercise has been correlated with a number of clinical and exercise measurements; important among these are the slope of the systolic pressure-to-end-systolic volume, end-systolic volume, cardiac index, pulmonary capillary wedge pressure, and wall stress. The changes in the regurgitant fraction, EF, and LV volume have shown considerable individual variability; they have also allowed a better understanding of the circulatory responses during exercise. Radionuclide angiography provides a reliable and reproducible method of measuring the rest LVEF that is important in the timing and the outcome of valve replacement. The value of the EF response to exercise in patient management is not yet clear; it is possible that other radionuclide-derived measurements at rest or during exercise, such as the systolic pressure-to-end-systolic volume relationship, and the end-systolic volume may provide complementary information to that provided by the EF.
mesh_terms: D001021:Aortic Valve / Q000601:surgery; D001022:Aortic Valve Insufficiency / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery; D003327:Coronary Disease / Q000150:complications / Q000000981:diagnostic imaging; D006350:Heart Valve Prosthesis; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D005082:Physical Exertion; D011868:Radioisotopes; D011877:Radionuclide Imaging; D012146:Rest; D013318:Stroke Volume; D013793:Thallium; D013997:Time Factors
chemical_list: D011868:Radioisotopes; D013793:Thallium