Investigation of Myocardial Contractile Reserve by Dobutamine Stress Transesophageal Echocardiography in Aortic and Mitral Regurgitation

Date de début de l'étude : 1 mai 1992

18 - 65 years of age. Patients with severe aortic regurgitation and patients with severe mitral regurgitation. Patients will discontinue medications 48 hours prior to the study. Women must not be pregnant. Patients must not have an associated valvular heart disease (i.e., patients with aortic regurgitation will be excluded if there is coexistent mitral valve disease; patients with mitral regurgitation will be excluded if there is coexistent aortic valve disease). Patients must not have any form of cardiomyopathy. Patients must not have coronary artery disease. Patients must not have ventricular ectopy during baseline conditions (i.e., couplets, frequent PVc's [greater than 6/min], early coupling ["R-on-T" phenomenon], ventricular bigeminy) that might potentially predispose the patient for the development of dangerous dysrhythmia during dobutamine infusion. Patients must not have a history of cardiac arrest or ventricular tachycardia. Patients must not have a history of congestive heart failure. Patients must not have hypotension (i.e., systolic blood pressure less than 100 mmHg). Patients must not have a systolic blood pressure greater than 200 mmHg. Patients must not have a left atrial size of greater than 100 mm. Patients must not have atrial fibrillation. Patients must not have sinus tachycardia greater than or equal to 100 beats/min. Patients must not have esophageal disease. Patients must not have any other medical condition that , at the discretion of the physician in charge, may increase the risk of the procedure.