Haemodynamic effects of arterial compliance, total peripheral resistance, and glyceryl trinitrate on regurgitant volume in aortic regurgitation.
OBJECTIVE
Afterload reduction is known to reduce regurgitant flow in patients with aortic regurgitation. Both arterial compliance and total peripheral resistance are determinants of afterload. The aim of this study was to evaluate the influence of arterial compliance and total peripheral resistance on the regurgitant volume.


METHODS
The values of arterial compliance and total peripheral resistance were assessed during aortic regurgitation at different regurgitant orifice areas in eight pigs before and after a bolus of glyceryl trinitrate. In a computer model the importance of arterial compliance and total peripheral resistance on the regurgitant volume was assessed by keeping each of them constant while the other variable was changed.


RESULTS
In both the experimental and computer models a very strong correlation was found between decreased total peripheral resistance and decreased regurgitant volume. Arterial compliance was of hardly any importance. A bolus of glyceryl trinitrate reduced regurgitant volumes and regurgitant fractions significantly.


CONCLUSIONS
Total peripheral resistance is an important factor in influencing the regurgitant volumes at a given regurgitant orifice area in aortic regurgitation, while arterial compliance is of less importance. Glyceryl trinitrate effectively reduces the regurgitant volumes by its effect on peripheral resistance.
Slørdahl
S A
SA
Department of Biomedical Engineering, University of Trondheim, Norway.
Piene
H
H
D000818:Animals; D001022:Aortic Valve Insufficiency / Q000503:physiopathology*; D001158:Arteries / Q000503:physiopathology; D003198:Computer Simulation; D004548:Elasticity; D006439:Hemodynamics / Q000187:drug effects / Q000502:physiology*; D008955:Models, Cardiovascular; D005996:Nitroglycerin / Q000494:pharmacology; D013552:Swine; D014655:Vascular Resistance / Q000187:drug effects / Q000502:physiology*
D005996:Nitroglycerin