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Table 2 Physiological vs cardiological systole and diastole

From: WEB downloadable software for training in cardiovascular hemodynamics in the (3-D) stress echo lab

Physiological systole Cardiological systole
Isovolumic contraction From M1 to A2, including:
Maximal ejection  
     Major part of isovolumic contraction*
     Maximal ejection
     Reduced ejection
Physiological diastole Cardiological diastole
Reduced ejection A2 - M1 interval (filling phases included)
Isovolumic relaxation  
Filling phases  
  1. In Greek, systole means contraction and diastole means "to send apart". Physiological systole lasts from the start of isovolumic contraction to the peak of the ejection phase, so that physiological diastole commences as the LV pressure starts to fall. This concept fits well with the standard pressure-volume curve. Physiological diastole commences as calcium ions are taken up into the SR, so that the myocyte relaxation dominates over contraction and the LV pressure starts to fall as shown on the pressure-volume curve. In contrast, cardiological systole is demarcated by the interval between the first and the second heart sounds, lasting from the first heart sound to the closure of the aortic valve. The remainder of the cardiac cycle automatically becomes cardiological diastole.
  2. * Note that M1 occurs with a definite albeit short delay after the start of the LV contraction. Modified from Opie LH. Mechanisms of cardiac contraction and relaxation. In: Braunwald E, Zipes DP, Libby P, Bonow RO, eds. Heart Disease. 7th ed. WB Saunders Company 2005, Chap.19:457-489, page 474.