Abstract
Nitroglycerin abbreviates left ventricular (LV) relaxation through improved hemodynamics as well as by direct actions on the myocardium. The aim of this study was to examine whether the changing systolic loading sequence during nitroglycerin administration affects LV relaxation in patients with excessive arterial load. By use of a conductance catheter with microtip manometer, the effects of intravenous nitroglycerin (0.3-0.5 microg/kg/min) on LV function and hemodynamics were examined in 39 patients with various degrees of LV contractility. Patients were divided into two groups according to LV-arterial coupling, the ratio of end-systolic elastance (Ees) to effective arterial elastance (Ea). In patients with Ees/Ea ratio > 1, nitroglycerin had no effect on the time to peak force or on the time constant of LV relaxation (tau). On the other hand, in patients with Ees/Ea < 1, which represented excessive arterial load, nitroglycerin significantly shortened the time to peak force, shifted the peak of the loading sequence from late to early systole, and significantly decreased tau without any changes in Ees. Thus, nitroglycerin improved LV relaxation in patients with excessive arterial load partly by changing the systolic loading sequence.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: 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.