Investigators studying shock accompanying acute myocardial infarction report some increase in survival of dogs treated with a selective vasodilator.
In this study, at the University of Minnesota Medical School, shock was defined as "a 35% or greater reduction in blood pressure and a 50% or greater reduction in cardiac output and electrocardiographic evidence of ischemia," Ronald H. Dietzman, MD, told JAMAMedical News.
Phenoxybenzamine was the vasodilator used, Dr. Dietzman said, adding:
"Maintenance of blood pressure with vasopressors is logical in those cases of cardiogenic shock which have a normal or lowered total peripheral resistance. But in most cases of cardiogenic shock, total peripheral resistance is elevated. Consequently, we chose to evaluate the effect of a vasodilator..."
Richard C. Lillehei, MD, PhD; Gary W. Lyons, MD; and Jack H. Bloch, MD, are other members of the research team.
Diffuse myocardial infarctions were produced in 122 adult mongrel dogs by closed