AIMS This study investigated the clinical and physiological significance of the dynamic left ventricle outflow gradient observed in some patients during dobutamine stress echocardiography. METHODS Three hundred and ninety-four consecutive patients completed dobutamine stress echocardiography using Doppler echocardiography to assess the presence of myocardial ischaemia and left ventricular out...

OBJECTIVE To assess the prognostic value of wall motion abnormalities during the recovery phase of dobutamine stress echocardiography in addition to wall motion abnormalities at peak stress. METHODS Wall motion abnormalities were assessed at peak and during recovery phase of dobutamine stress echocardiography in 187 consecutive patients, who were followed for occurrence of cardiac events. R...

BACKGROUND There are no published clinical trials comparing dobutamine with milrinone in outpatients with stage D heart failure on continuous inotropes. METHODS AND RESULTS In a retrospective analysis of 112 inotrope-dependent patients with stage D heart failure who were not transplant candidates at enrollment, we investigated the relationship between choice of dobutamine or milrinone and mor...

We tested whether or not endogenous nitric oxide (NO) attenuates beta-adrenergic inotropic responsiveness during normoperfusion or moderate myocardial ischemia. In 13 anesthetized pigs with a cannulated left anterior descending (LAD) coronary artery, the maximal contractile responses to intracoronary dobutamine and calcium were assessed during normoperfusion and at the end of a 90-min period of...

BACKGROUND The role of cholinergic pathways in modulating left ventricular contractile function in humans is not known. This study evaluated the effect of a cholinergic agonist (acetylcholine) and antagonist (atropine) on basal and beta-adrenergically stimulated left ventricular contractile function in normal subjects and subjects with denervated hearts after cardiac transplantation. METHODS ...

INTRODUCTION The long-term use of positive inotropic pharmaceuticals in patients suffering from end-stage congestive heart failure (CHF) has been associated with increased mortality, presumed to be due to proarrhythmia. Oral amiodarone combined with intermittent dobutamine infusions (IDI), on the other hand, has been shown to increase survival. This study evaluated the effects of oral amiodaron...

Hypoxia has been reported to alter left ventricular (LV) diastolic function, but associated changes in right ventricular (RV) systolic and diastolic function remain incompletely documented. We used echocardiography and tissue Doppler imaging to investigate the effects on RV and LV function of 90 min of hypoxic breathing (fraction of inspired O(2) of 0.12) compared with those of dobutamine to re...

BACKGROUND We studied the effect of an antioxidant, the intracoronary infusion of vitamin C, on basal and dobutamine-stimulated left ventricular (LV) contractility. METHODS AND RESULTS Nineteen patients with normal ventricular function participated in this study. A micromanometer-tipped catheter was inserted into the LV. In the experimental group (n=10), an infusion catheter was positioned in...

BACKGROUND Although aortic valve replacement can be performed at an acceptable risk level in selected patients with left ventricular systolic dysfunction and low-output, low-gradient aortic stenosis, not all patients presenting with these hemodynamics will benefit from the operation. Some patients may have only mild aortic stenosis, despite a small calculated valve area. We report on the clinic...