Abstract
Prostacyclin (PGI2), a potent vasodilatory substance that effectively inhibits platelet aggregation is under clinical investigation for the treatment of angina pectoris. We studied the effects of PGI2 on transient drug-induced myocardial dysfunction in anesthetized, thoracotomized dogs. Regional myocardial function was assessed using two pairs of piezoelectric transducers and a multidimensional measuring gauge; one pair was implanted in the distribution area of the left circumflex branch (LCX) and the other in the distribution area of the descending branch (LAD) of the left coronary artery. After intravenous injection of isoproterenol (ISO), which led to an increase in systolic shortening in the LCX and LAD areas, a critical stenosis was performed on the LCX and maintained at this level. Intravenous ISO injection now induced regional dysfunction in the LCX-dependent segment with the occurrence of systolic bulging. Infusion of PGI2 at a dosage of 100 ng/kg/min caused a decrease in arterial blood pressure and an increase in heart rate, but had no effect on regional myocardial function. ISO-induced myocardial dysfunction in the critically stenosed LCX segment, which was observed before PGI2 administration, was not ameliorated, but rather aggravated, by PGI2. It may be concluded that PGI2 does not improve normal or ISO-stimulated myocardial function in pressure-dependent perfused areas of the heart.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
