Effects of halothane on global and regional biventricular performances and on coronary hemodynamics before and during right coronary artery stenosis in the dog.
BACKGROUND
Previously, it was suggested that right ventricular (RV) free wall dysfunction does not necessarily elicit global hemodynamic alterations. This was investigated in a canine model of halothane-induced right coronary artery (RCA) insufficiency.


METHODS
Two concentrations (0.8% and 1.6% end tidal) of halothane on global and regional RV and left ventricular (LV) performance and on coronary, pulmonary, and systemic hemodynamics were studied in 10 open-chest dogs first before and, subsequently, during critical RCA stenosis.


RESULTS
In the absence of stenosis, halothane caused progressive and comparable depression of regional and global RV and LV function and reduction of RCA flow. Halothane administered during RCA stenosis caused disproportionate decreases in RCA flow and segment shortening and increases in systolic segment lengths in the area supplied by the stenosed RCA that were approximately twice as great as before stenosis. Such severe regional RV dysfunction was not accompanied by greater depression of global RV and LV pump function (systolic pressures and stroke volume).


CONCLUSIONS
In the canine heart with its dominant left coronary system, RCA insufficiency (on the basis of halothane-induced hypotension) caused regional RV dysfunction suggesting ischemia that was not accompanied by global hemodynamic alteration.
Priebe
H J
HJ
Department of Anesthesia/University Hospital, Freiburg, Germany.
D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000503:physiopathology; D001794:Blood Pressure / Q000187:drug effects; D003326:Coronary Circulation / Q000187:drug effects; D003327:Coronary Disease / Q000503:physiopathology*; D003331:Coronary Vessels / Q000187:drug effects / Q000503:physiopathology; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D005260:Female; D006221:Halothane / Q000008:administration & dosage / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D011651:Pulmonary Artery / Q000187:drug effects / Q000503:physiopathology; D013318:Stroke Volume / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects; D016277:Ventricular Function, Left / Q000187:drug effects*; D016278:Ventricular Function, Right / Q000187:drug effects*
D006221:Halothane