Fig. 1.
Panel a, illustration of a left ventricular pressure-volume loop of a cardiac cycle. A, isovolumetric contraction; B, ejection phase; C, isovolumetric relaxation; D, filling phase; EDV, end-diastolic volume; EDP, end-diastolic pressure; ESV, end-systolic volume; ESP, end-systolic pressure. Panel b, illustration of a pressure-volume loop of a dilated and failing left ventricle. ESPVR, end-systolic pressure-volume relation; EDPVR, end-diastolic pressure-volume relation, EA, effective arterial elastance. Note the decreased contractility indicated by the decreased slope (EES) and the rightward shift of the ESPVR. The end-diastolic stiffness has increased indicated by the slope of the EDPVR. The left ventricular distensibility has decreased indicated by the upward shift of the EDPVR. Furthermore, left ventricular performance has decreased indicated by decrease in the ventricular-arterial coupling ratio (EES/EA)