Abstract |
Xamoterol, a new partial beta 1-adrenoceptor agonist, was evaluated in respect to its hemodynamic and energetic effects when given acutely i.v. (0.2 mg/kg body weight) to 10 patients with idiopathic dilated cardiomyopathy. Hemodynamically, a small drop in left ventricular end-systolic volume index (from 105 +/- 38 to 91 +/- 48 ml/m2; p less than 0.05) and end-diastolic volume index (from 168 +/- 44 to 152 +/- 41 ml/m2; p less than 0.05) and an increase in maximum rate of left ventricular pressure rise (from 1,003 +/- 358 to 1,283 +/- 398 mm Hg/s; p less than 0.001) was observed. The systolic stress-time integral was only slightly reduced after injection of xamoterol, from 107 +/- 28 to 94 +/- 35 x 10(3) dyn.s/cm2 (NS). Other conventional hemodynamic variables did not change significantly. Myocardial oxygen consumption per beat increased from 125 +/- 39 microliters/beat/100 g to 153 +/- 62 microliters/beat/100 g (p less than 0.05). The ratio of myocardial oxygen consumption per beat and stress-time integral--as an inverse measure of left ventricular contraction economy--increased significantly, from 132 +/- 62 to 192 +/- 115 microliters/beat/10(3) dyn.s/cm2 (p less than 0.02) after injection of xamoterol, whereas left ventricular efficiency decreased from 17.6 +/- 7.8 to 13.8 +/- 6.5% (p less than 0.05). Thus, in idiopathic dilated cardiomyopathy, xamoterol exhibited only minor hemodynamic effects whereas myocardial contraction economy and efficiency were significantly reduced.
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Authors | L Thierfelder, C Holubarsch, G Hasenfuss, H W Heiss, H Just |
Journal | Journal of cardiovascular pharmacology
(J Cardiovasc Pharmacol)
Vol. 17
Issue 4
Pg. 593-9
(Apr 1991)
ISSN: 0160-2446 [Print] United States |
PMID | 1711626
(Publication Type: Journal Article)
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Chemical References |
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Topics |
- Adult
- Aged
- Cardiomyopathy, Dilated
(drug therapy, metabolism)
- Coronary Circulation
- Energy Metabolism
(drug effects)
- Female
- Heart
(drug effects)
- Hemodynamics
(drug effects)
- Humans
- Male
- Middle Aged
- Myocardium
(metabolism)
- Oxygen Consumption
(drug effects)
- Propanolamines
(pharmacology)
- Xamoterol
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