Cardiac action potential action potential (see phase 2, below) and is a fundamental step in cardiac excitation-contraction coupling. There are important physiological differences between the cells that spontaneously generate the action potential (pacemaker cells; e.g. SAN) and those that simply conduct it (non-pacemaker cells; e.g. ventricular myocytes). The specific differences in the types of ion channels expressed and mechanisms by which they are activated results in differences in the configuration of the action potential waveform, as shown in figure 2. The standard model used to understand the cardiac action potential is that of the ventricular myocyte. Outlined below are the five phases of
Cardiac output a function of the rate of blood flow and the rate of oxygen picked up by the red blood cells. Application of the Fick principle involves calculating the oxygen consumed over time by measuring the oxygen concentration of venous blood and arterial blood. "Q" is calculated from these measurements as follows: From these values, we know that: formula_20 where This allows us to say Cardiac output Cardiac output (CO, also denoted by the symbols formula_1 and formula_2), is a term used in cardiac physiology that describes the volume of blood being pumped by the heart, in particular by the left