Cardiac and hemodynamic effects of the selective bradycardic agent KC 8857 during exercise-induced myocardial ischemia.
The effects of an in vitro bradycardic agent without negative inotropism, KC 8857 (3,7-di-(cyclopropylmethyl)-9,9-tetramethylene-3,7-diazabicyclo-[3.3.1]- nonane dihydrochloride), were tested in chronically instrumented dogs in a model of exercise-induced myocardial ischemia. KC 8857 was i.v. infused during critical stenosis of the circumflex branch of the left coronary artery which led to exercise-induced myocardial dysfunction. KC 8857 caused a decrease in heart rate, left ventricular dp/dtmax and calculated myocardial oxygen demand at rest and during exercise. Since positive dp/dtmax values at a given heart rate were not altered by KC 8857 it may be assumed that myocardial function was restored mainly by the decrease in heart rate.
Grohs
J G
JG
Pharmakologisches Institut der Universität Wien, Austria.
Fischer
G
G
Raberger
G
G
D000818:Animals; D001643:Bridged Bicyclo Compounds / Q000494:pharmacology*; D019086:Bridged Bicyclo Compounds, Heterocyclic; D001952:Bridged-Ring Compounds / Q000494:pharmacology*; D002316:Cardiotonic Agents / Q000494:pharmacology*; D003327:Coronary Disease / Q000503:physiopathology*; D003521:Cyclopropanes / Q000494:pharmacology*; D004285:Dogs; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D009200:Myocardial Contraction / Q000187:drug effects; D009206:Myocardium / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects; D005082:Physical Exertion
D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D001952:Bridged-Ring Compounds; D002316:Cardiotonic Agents; D003521:Cyclopropanes; C059921:tedisamil