For (C) : Tau=200ms and Vstroke=70mL. Please plot over the following range: 60<H
ID: 35807 • Letter: F
Question
For (C) : Tau=200ms and Vstroke=70mL. Please plot over the following range: 60<HR<300.
. Effect of heart rate on cardiac output. At high heart rates, the ability to pump blood is limited by filling of the left ventricle. (A) Show that the filling of the left ventricle occurs as Vvent = k1 - k2exp(-t/tau), where k1 = VED and k2 = VED-VES. Assume that filling of the ventricle is entirely passive (i.e. neglect atrial contraction) and that airial filling pressure is constant. (B) Given this filling equation, derive an expression for CO (in ml) = f(HR (in bpm)). (Hint: remember tcycle = tsystole ? tdiastole and filling only occurs during diastole.) (C) Plot CO = f(HR) for tsystole = 100, 150, 200, 250, 300, and 400 ms. Explain what happens. For (C) : Tau=200ms and Vstroke=70mL. Please plot over the following range: 60Explanation / Answer
Pes = Ees (Ved-Vo-Vj),
taTau (tau), the time constant for isovolumic relaxation, is often used as a measure of cardiac diastolic function. However, several methods of calculating tau have been published which may produce different results and, thereby, different conclusions. The purpose of this study was to determine if the method of tau calculation effects the results when left ventricular pressure (LVP) is measured at different positions along the base-to-apex axis. u, the time constant for isovolumic relaxation, along the left ventricular base-to-apex axis.