Treatment with captopril has proved effective in some patients with resistant heart failure. Since cardiac output responses to captopril treatment are generally small, we infused the positive inotropic agent dobutamine in six patients already receiving captopril to determine whether cardiac output could be augmented without concomitantly increasing myocardial oxygen demands. At low infusion rat...

OBJECTIVES We hypothesized that, although the effects of dipyridamole and dobutamine on myocardial blood volume (MBV) and mean microbubble velocity (VEL) are different, the magnitude of perfusion deficit during both forms of stress is the same because both drugs unmask abnormal myocardial blood flow (MBF) reserve. BACKGROUND Both dipyridamole and dobutamine are used clinically as pharmacologi...

Reasons for performing study: High-dose dobutamine stress echocardiography has been shown to be cardiotoxic and arrhythmogenic in horses. However, the test may have benefit in practice as a pharmacological challenge of exercise without the treadmill being required. Objectives: To investigate the effect of dobutamine on cardiac performance in ponies previously treated with atropine, in order to ...

OBJECTIVES We examined the relationship among viability assessment by dobutamine echocardiography (DE), positron emission tomography (PET) and thallium-201 single-photon emission computed tomography (TI-SPECT) to the degree of fibrosis. BACKGROUND DE, PET and TI-SPECT have been shown to be sensitive in identifying viability of asynergic myocardium. However, PET and TI-SPECT indicated viabilit...

We wanted to determine the efficacy of dobutamine infusions and Prbc transfusions on splanchnic tissue oxygen utilization by measuring gastric pHi. Physiologic parameters and pHi measurements via the use of a gastric tonometer were obtained in 21 septic patients before and after the administration of a dobutamine infusion (5 micrograms/kg/min) or the transfusion of two units of Prbc. Subsets of...

The aim of this study was to investigate the effect of combined atropine low-dose dobutamine stress test on left ventricular parameters in adult warmblood horses, to establish a potential protocol for pharmacological stress echocardiography. Seven healthy untrained warmblood horses aged 9 to 22 years were used. Heart rate (HR) and left ventricular B- and M-mode dimensions were recorded at basel...

[1] in the previous issue of Critical Care. Th e authors suggested, in a retrospective analysis, that dobutamine use in patients undergoing cardiac surgery was independently associated with a 2.3-fold increase in mortality and a 2.7-fold increase in risk of renal dysfunction. We have some concerns regarding this conclusion. Th e primary concern with this analysis is the choice of covariates inc...

Insufficient cardiac preload and impaired contractility are frequent in early sepsis. We explored the effects of acute cardiac preload reduction and dobutamine on hepatic arterial (Qha) and portal venous (Qpv) blood flows during endotoxin infusion. We hypothesized that the hepatic arterial buffer response (HABR) is absent during preload reduction and reduced by dobutamine. In anesthetized pigs,...

Milrinone, a phosphodiesterase 3 (PDE3) inhibitor, is known to enhance left ventricular (LV) contractility by an inhibition of the breakdown of cAMP through the mechanism inhibiting PDE3. However, it is unclear whether milrinone also exerts positive lusitropy, like dobutamine. Here, we assessed the effects of milrinone on in vivo LV relaxation, as well as the Ca(2+)-ATPase activity and the Ca(2...

Despite intensive investigation, the role of nitric oxide (NO) in cholinergic modulation of myocardial contractility remains unresolved. The left anterior descending coronary artery of 34 anesthetized, open-chest dogs was perfused via an extracorporeal circuit. Segmental shortening (SS) was measured with ultrasonic crystals and coronary blood flow (CBF) was measured with an ultrasonic flow tran...