Long-term effects of xamoterol on left ventricular diastolic function and late remodeling: a study in patients with anterior myocardial infarction and single-vessel disease.

Abstract

The purpose of the study was to examine whether the prolonged administration of the beta 1-adrenoceptor partial agonist xamoterol could improve left ventricular diastolic function and affect the global remodeling process of the left ventricle after anterior myocardial infarction. In 22 patients with anterior myocardial infarction and single-vessel disease, left ventricular angiography (+ Millar) was performed under basal conditions 1 to 2 months after the acute myocardial infarction. Eight patients were then treated for 3 months with placebo and 14 were treated with xamoterol (200 mg bid) and a second left ventricular angiographic study was performed. Angiograms were digitized frame by frame to derive the diastolic pressure-volume relationship and to compute wall stress. An index of elastic myocardial stiffness was computed at a constant stress of 30 kdynes/cm2 before and after treatment. To evaluate changes in left ventricular shape, segmental areas in anterior and inferior segments were computed and compared at end-diastole and end-systole. After xamoterol, left ventricular end-diastolic pressure and mean diastolic wall stress decreased (from 24 +/- 5 to 15 +/- 5 mm Hg and from 57 +/- 32 to 38 +/- 22 kdynes/cm2, respectively; both p less than .01 vs baseline and vs placebo). These changes were accompanied by a downward shift in the diastolic pressure-volume relationship and by a decrease in the index of myocardial stiffness from 526 +/- 270 to 371 +/- 194 kdynes/cm2 (p less than .02).(ABSTRACT TRUNCATED AT 250 WORDS)

Propranolol therapy in experimental heart failure in rabbits improves cardiac response to catecholamines without beta‐adrenoceptor up‐regulation

“…Since the first description by Waagstein e f a1 (1975) of an improvement of myocardial function and exercise capacity in patients with chronic heart failure with beta-blocking agents, clinical studies showed that this treatment decreases mortality and sudden death (Chadda et al, 1986) and improves ventricular function at rest and during exercise (Engelmeir et al, 1985;Chadda et al, 1986;Pouleur et al, 1988;Heilbrunn et al, 1989;de Feyter et al, 1990;Eichhorn et al, 1990) in patients with heart failure independently of its etiology and of the drug which was used. Although basal ventricular function was not different in treated and in non-treated rabbits of our study (table II) .…”

ß Blockers With ACE Inhibitors in Mild Heart Failure

“…Moreover, a variety of inflammatory cytokines are elevated in patients with LV dysfunction, 36,38 suggesting a role of these substances in progressive deterioration of LV function. Importantly, both ACE inhibitors 16 and ß blockers 17–19 have been shown to favorably alter deterioration in LV function. However, since ß blockers and ACE inhibitors may act through different mechanisms, their combination might be anticipated to be additive, or possibly synergistic.…”

Intropic agents in the treatment of heart failure: Despair or hope?

“…Xamoterol has a partial beta-agonist effect and stabilizes the cardiac response to sympathetic drive. Preliminary studies suggested that this agent could benefit patients with chronic heart failure if adequate doses are used by improving diastolic function and exercise capacity [10,11]. However, the excess mortality was associated with 3-month treatment with this agent of patients with severe heart failure [12].…”