DECREASED RIGHT HEART BLOOD-VOLUME DETERMINED BY MAGNETIC-RESONANCE-IMAGING - EVIDENCE OF CENTRAL UNDERFILLING IN CIRRHOSIS

Whether the central blood volume is reduced or expanded in cirrhosis i s still under debate. Accordingly, the current study was undertaken to assess the volume of the heart cavities. Ten cirrhotic patients and m atched controls had their right and left ventricular end-diastolic vol umes (RVDV and LVDV), and end-systolic volumes (RVSV and LVSV) determi ned by magnetic resonance imaging (MRI), RVDV (122 vs. control 166 mL, P < .02), RVSV (41 vs, 80 mt, P < .02) and right atrial volume (47 vs . 64 mL, P < .05) were significantly reduced in the patients. In contr ast, LVDV (134 vs. 129 mL, NS), LVSV (54 vs. 40 mL, NS), and left atri al volume (70 vs. 57 mL, P = .O5) were normal or slightly increased. T he right ejection fraction (68% vs. 53%, P < .05) was significantly in creased, but the left ejection fraction was slightly reduced (61% vs. 69%, NS). The central and arterial blood volume (CBV), assessed as the cardiac output (CO) multiplied by the central circulation time, was s ignificantly decreased (1.47 vs. 1.81 L, P < .05). The noncentral bloo d volume (4.43 vs. 3.64 L, P < .02), plasma volume (4.05 vs. 3.27 L, P < .02), and CO (7.11 vs, control 5.22 L/ min, P < .01) were significa ntly increased in the patients. CCT (13.1 vs. 20.0 sec, P < .005) and the right ventricular transit time (0.79 vs. 1.35 sec, P < .005) were significantly reduced, but the left ventricular transit time was norma l (0.91 vs. 0.88 sec, NS). Systemic vascular resistance was reduced (9 91 vs. 1,490 dynsec/cm(5), P < .01), Our results are in keeping with a hyperkinetic circulation in cirrhotic patients with central vascular underfilling with reduced right heart blood volume and central and art erial blood volume. The normal. or slightly increased left heart blood volume suggests a complex pattern with a relatively decreased left ve ntricular function. The results support the concept of an abnormal dis tribution of the blood volume, with central and arterial underfilling (consequent on the combination of decreased systemic vascular resistan ce and left ventricular dysfunction) as major elements in the abnormal fluid homeostasis in cirrhosis.