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Figure 8 LV Wall Stress–Volume Diagrams in Heart Failure

The normal end-systolic wall stress–volume relation is represented by the dashed line, and this relation in heart failure is shifted downward with reduced slope. The resting left ventricular (LV) wall stress–volume loop in heart failure (1) shows little pre-load reserve, and increased afterload induced by angiotensin (loop 2) causes a marked decrease in the stroke volume (SV2). Administration of a vasodilator (loop 3) compared with loop 1 causes reduced afterload particularly early and late during LV ejection, an increase in stroke volume (SV3), with a modest decrease in LV end-diastolic volume. Reproduced with permission from Ross J Jr. Mechanisms of cardiac contraction: what roles for preload, afterload and inotropic state in heart failure? Eur Heart J 1983;4:19–38.