ALTERED CARDIOVASCULAR RESPONSIVENESS TO ACTIVE TILTING IN NONALCOHOLIC CIRRHOSIS

Background & Aims: The hyperdynamic circulation of cirrhosis has been related either to plasma volume expansion (increased preload) or perip heral arterial vasodilation (reduced afterload). The aim of this study was to evaluate cardiovascular function in patients with nonalcoholic cirrhosis by echocardiography. Methods: Nineteen patients with abnorm al sodium handling (11 sodium excretors and 8 sodium retainers) and 15 healthy volunteers underwent echocardiographic evaluation of left Ven tricular end-diastolic Volume index (LVEDVI) and left Ventricular end- systolic Volume index (LVESVI), left ventricular ejection fraction (LV EF), cardiac index (CI), mean arterial pressure, and systemic vascular resistance (SVR) during supine resting and after 5 minutes of standin g. Results: Supine patients had increased LVEF and CI and reduced LVES VI and SVR. LVEDVI was increased only in sodium excretors. Standing in duced a decrease in LVEDVI in all subjects. Healthy volunteers maintai ned cardiovascular homeostasis by increasing LVEF and heart rate, wher eas cirrhotic patients experienced a decrease in SVI and CI despite ma rked increments in heart rate, plasma renin activity, and plasma norep inephrine level. Conclusions: In patients with cirrhosis, the increase d LVEF and reduced LVESVI while in a supine position point at reduced afterload as an important determinant of the hyperdynamic circulation. Evidence of an increased preload secondary to increased blood volume, indicated by a high LVEDVI and increased plasma atrial natriuretic pe ptide levels, was found only in sodium excretors. The altered response to active tilt in cirrhotic patients suggests an impaired myocardial contractility.