Effects of a cardioselective beta 1 partial agonist (corwin) on left ventricular function and myocardial metabolism in patients with previous myocardial infarction.
Corwin is a new selective beta 1 partial agonist, able to stabilize the beta 1 adrenoceptors at approximately 43% of their maximal activity. The aim of the study was to determine the effects of this agent in patients with coronary artery disease (CAD) and previous myocardial infarction (MI). In a first group of 14 patients, corwin increased significantly the peak (+)dP/dt (+35%; p less than 0.005), the global ejection fraction, and the ejection fraction of abnormally contracting segments (from 20 +/- 18 to 26 +/- 19%; p less than 0.02). Corwin also induced significant decreases in mean systolic (-8%; p less than 0.05) and mean diastolic (-38%; p less than 0.001) wall stress and accelerated the relaxation rate. In a second group of 11 patients, a metabolic study indicated that neither myocardial oxygen consumption (15 +/- 7 versus 15 +/- 7 ml/min; difference not significant) nor lactate extraction was modified by the drug. In this group, increases in peak (+)dP/dt, acceleration in ventricular relaxation (-8 ms in time constant of isovolumic pressure decrease; p less than 0.01), and decreases in left ventricular end-diastolic pressure also were noted after administration of corwin, both under basal conditions and during a cold pressor test. In conclusion, corwin is a positive inotrope which, in patients with CAD and left ventricular dysfunction, improves left ventricular systolic and diastolic function without inducing myocardial ischemia.
D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000328:Adult; D003327:Coronary Disease / Q000188:drug therapy; D006352:Heart Ventricles / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects; D009203:Myocardial Infarction / Q000188:drug therapy*; D009206:Myocardium / Q000378:metabolism*; D011412:Propanolamines / Q000378:metabolism / Q000494:pharmacology*; D013318:Stroke Volume / Q000187:drug effects; D017307:Xamoterol
D000318:Adrenergic beta-Agonists; D011412:Propanolamines; D017307:Xamoterol