Aerobic exercise capacity in COPD patients with and without pulmonary hypertension.

Pulmonary hypertension is a common occurrence in advanced COPD, but its effects on exercise capacity remain undetermined. Exercise testing and an echocardiographic examination were performed in 29 patients with advanced stable COPD. Mean pulmonary artery pressure (mPAP) was calculated from the acceleration time of pulmonary flow.

Usefulness of dobutamine stress tests for detection of cardiac abnormalities in dogs with experimentally induced early left ventricular dysfunction.

Objective: To determine whether dobutamine stress tests (DST) can be used to detect cardiac dysfunction in dogs with early left ventricular dysfunction (ELVD) induced by rapid right ventricular pacing (RRVP).

Animals: 7 adult male Beagles.

Procedure: A pacemaker was surgically implanted in each dog at the level of the right ventricular apex.

Hormonal response to dobutamine cardiac stress testing in a conscious canine model of early left ventricular dysfunction induced by chronic rate overload.

The aims of this study were to investigate (1) hormonal activation before and during dobutamine cardiac stress testing (DST) in a canine model of early left ventricular dysfunction (ELVD) induced by rapid right ventricular pacing (RRVP) and (2) the relationship between this hormonal profile and carnitine concentrations. Before the pacing period, the 6 dogs were assigned to 2 groups according their baseline total plasma carnitine concentration. A DST was performed on each dog before activation of the pacemaker and every 3 to 4 days during development of 3 progressive stages of ELVD (stages 1, 2 and 3).