title: Aortic wave dynamics and its influence on left ventricular workload.
abstract: The pumping mechanism of the heart is pulsatile, so the heart generates pulsatile flow that enters into the compliant aorta in the form of pressure and flow waves. We hypothesized that there exists a specific heart rate at which the external left ventricular (LV) power is minimized. To test this hypothesis, we used a computational model to explore the effects of heart rate (HR) and aortic rigidity on left ventricular (LV) power requirement. While both mean and pulsatile parts of the pressure play an important role in LV power requirement elevation, at higher rigidities the effect of pulsatility becomes more dominant. For any given aortic rigidity, there exists an optimum HR that minimizes the LV power requirement at a given cardiac output. The optimum HR shifts to higher values as the aorta becomes more rigid. To conclude, there is an optimum condition for aortic waves that minimizes the LV pulsatile load and consequently the total LV workload.
authors.affiliation: Option of Bioengineering, Division of Engineering & Applied Sciences, California Institute of Technology, Pasadena, California, United States of America.
authors.forename: Niema M
authors.initials: NM
authors.lastname: Pahlevan
authors.forename: Morteza
authors.initials: M
authors.lastname: Gharib
mesh_terms: D001011:Aorta / Q000502:physiology*; D003198:Computer Simulation; D006339:Heart Rate / Q000502:physiology; D008955:Models, Cardiovascular; D011312:Pressure; D011674:Pulse; D016277:Ventricular Function, Left / Q000502:physiology*