Pathophysiology and Evaluation of Severity of Congestive Heart Failure on the Basis of Venous Characteristics : SYMPOSIUM ON PATHOPHYSIOLOGY AND SEVERITY OF HEART FAILURE IN THE ASPECT OF CIRCULATORY INSUFFICIENCY

Abstract

To elucidate the possibility of grading the severity of congestive heart failure by usingvenous characteristics, we constructed venous pressure-volume curves (PVR) and calculated venous stiffness constants (K). In addition, effects of vasoactive drugs on venous distensibility were studied. A venous pressure-volume curve could be fit well by an exponential curve (r=0.98±0.01). The PVR was shifted to the left with an increase in the clinical severity of congestive heart failure. The exponent of these curves, K, increased as the PVR was shifted to the left. K correlated with heart rate (r=0.52, p<0.01), right atrial pressure (r=0.54, p<0.02) and mean pulmonary arterial pressure(r=0.47, p<0.04). Nitroglycerin and amrinone dilated veins and decreased K by 19.6 ± 6.9% (p<0.03) and 14.0 ± 4.3% (p<0.02), respectively. Changes in K (ΔK) during the nitroglycerin and amrinone infusions correlated closely with the baseline K (ΔK=-0.41K+0.22, r=0.92, p<0.01). Therefore, the venodilating effects of these drugs were greater in patients with more severe congestive heart failure. The venous stiffness constant could be useful to grade the severity of congestive heart failure.