1. Pressure and volume are related in the ventricle through the compliance relationship depicted here. Normal compliance curve (A) relates changes in left ventricular volume to changes in left ventricular pressure. Moving along the normal curve, increases in left ventricular volume are initially tolerated with minimal changes in pressure. However, as end-diastolic volume increases, the left ventricular end-diastolic pressure rises. The less compliant curve (C) reflects a left ventricle as might be seen in a patient with a chronic pressure overload of the left ventricle such as in aortic stenosis or chronic hypertension. Here, left ventricular end-diastolic pressure rises rapidly with changing volume conditions. Consequently, such patients are at risk for the development of pulmonary edema with minimal increases in left ventricular end-diastolic volume. Conversely, the highly compliant curve (B) reflects a heart, which accommodates large changes in volume with minimal changes in pressure. Such conditions might be seen in patients with chronic, compensated aortic or mitral regurgitation whereby the left ventricle is volume overloaded. In time compensatory mechanisms fail and the ventricle becomes progressively noncompliant. (From: William J Hoffman, John D Wasnick, eds. Postoperative Critical Care of the Massachusetts General Hospital. 2nd ed. Boston, MA: Wolters Kluwer; 1992, with permission.)
Source: Chapter 2. Hemodynamics and Cardiac Anesthesia, Cardiac Anesthesia and Transesophageal Echocardiography
Citation: Wasnick JD, Hillel Z, Kramer D, Littwin S, Nicoara A. Cardiac Anesthesia and Transesophageal Echocardiography; 2011 Available at: Accessed: October 29, 2017
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