OBJECTIVES The aim of this study was to determine the safety of dobutamine stress myocardial perfusion imaging (MPI) obtained by real-time contrast echocardiography (RTCE) and intravenous ultrasound contrast in a large cohort of patients with suspected coronary artery disease (CAD). BACKGROUND Despite the increasing number of studies showing the potential clinical utility of myocardial contra...

BACKGROUND In a correlative functional/histopathologic study, we investigated the regional deformation characteristics of both chronic nontransmural and transmural infarctions before and after a dobutamine challenge. METHODS AND RESULTS After stenosing copper-coated stent implantation to produce circumflex artery endothelial proliferation, 18 pigs were followed up for 5 weeks. Posteuthanasia ...

BACKGROUND The synthetic catecholamine dobutamine increases stroke volume in normal subjects and in patients with congestive heart failure. In addition to its direct influence on myocardial contractility, dobutamine may significantly modulate vascular tone because of its alpha- and beta-adrenergic agonist activity. METHODS AND RESULTS To test the hypothesis that such vasoactive properties sig...

BACKGROUND Both radionuclide perfusion tracers and contractile response to dobutamine have been used to identify hibernating myocardium. The aim was to compare 201Tl (thallium) single photon emission CT (SPECT), 99mTc-tetrofosmin (tetrofosmin) SPECT, and dobutamine cine MRI for identifying regions of reversible myocardial dysfunction. METHODS AND RESULTS Thirty patients with 3-vessel coronary...

BACKGROUND To study the effects of Beta-blockers during Dobutamine Stress Echocardiography (DSE) comparing the hemodynamic benefits of an early administration of atropine in patients taking or not Beta-blockers. METHODS One hundred and twenty-one patients were submitted to dobutamine stress echocardiography for the investigation of myocardial ischemia. The administration of atropine was rando...

STUDY OBJECTIVE To prospectively address the question whether the assessment of valvular hemodynamics and myocardial function during low-dose dobutamine infusion can guide decision making in patients with aortic stenosis and left ventricular (LV) dysfunction. PATIENTS AND MEASUREMENTS Twenty-four patients with aortic stenosis and LV dysfunction (mean ejection fraction, 28%; New York Heart Ass...

Aged individuals have impaired diastolic relaxation– lusitropic function. Dobutamine, a selective 1-adrenergic agonist, is used to augment systolic cardiac function at the termination of cardiopulmonary bypass (CPB). However, our question is whether dobutamine will also enhance the lusitropic function in the aged individual. The myocyte mechanism for the rate of ventricular relaxation is depend...

We studied the conditioning effects of chronic infusion of dobutamine and exercise training in three groups of chronically instrumented dogs. One group was infused with normal saline, a second group was infused with dobutamine (40 mug/kg per min), and the third group was exercised on a treadmill at 4 mph, up a 10 degrees incline. Each group was either infused or exercised for 2 h a day, 5 d a w...

OBJECTIVE To investigate the functional significance of chronotropic incompetence during dobutamine stress echocardiography. PATIENTS AND METHODS The functional significance of chronotropic incompetence was evaluated during dobutamine stress echocardiography in 512 patients without beta blocker treatment who underwent dobutamine stress echocardiography (up to 40 microg/kg/min) and completed t...

We report a case of cardiac asystole during dobutamine stress echocardiography in a 59 year-old woman presenting with chest pain and a positive treadmill test for ischemia. Cardiac asystole was not associated with myocardial ischaemia and was probably related to a powerful cardioinhibitory reflex caused by dobutamine stimulation.