Yano M, Kohno M, Yamamoto T, Hisaoka T, Tanigawa T, Ono K, Lee B, Konishi M, Matsuzaki M
Second Department of Internal Medicine, Yamaguchi University School of Medicine, Ube, Japan.
J Cardiovasc Pharmacol. 1998 Sep;32(3):466-70. doi: 10.1097/00005344-199809000-00018.
An arteriovenous vasodilator, flosequinan, has been shown to be effective for the treatment of acute heart failure. However, little is known as to its effect on aortic impedance, which is known to be a proper and precise expression of left ventricular (LV) afterload. To evaluate the acute cardiovascular effect of flosequinan in failing heart, we administered flosequinan intravenously to seven dogs with cardiac failure produced by an infusion of carbon powder (20-50 microm in diameter) into left main trunks of coronary artery. The LV-pump function was severely impaired after intracoronary injection of carbon powder, as evidenced by the findings that cardiac output, circumferential shortening velocity (mean Vcf), and peak +dP/dt of LV pressure were all decreased, associated with a significant increase in LV end-diastolic pressure. Flosequinan (0.9 mg/kg, i.v.) increased cardiac output by 28%, mean Vcf by 44%, and peak +dP/dt by 24%, whereas it decreased total systemic resistance by 32%, time constant of LV pressure decay by 22%, and LV end-diastolic pressure by 18%. Moreover, flosequinan substantially decreased the pulsatile components of LV afterload (i.e., characteristic impedance by 11% and arterial wave reflection coefficient by 45%). Thus flosequinan exerted not only positive inotropic but also positive lusitropic effects, in association with a significant reduction of both pulsatile and steady components of LV afterload, contributing to an improvement of LV-pump function in acute cardiac failure.
一种动静脉血管扩张剂氟司喹南已被证明对治疗急性心力衰竭有效。然而，关于其对主动脉阻抗的影响却知之甚少，而主动脉阻抗是左心室（LV）后负荷的一种恰当且精确的表达。为了评估氟司喹南对衰竭心脏的急性心血管作用，我们对7只通过向冠状动脉左主干内注入碳粉（直径20 - 50微米）而导致心力衰竭的犬静脉注射氟司喹南。冠状动脉内注射碳粉后左心室泵功能严重受损，心输出量、圆周缩短速度（平均Vcf）和左心室压力峰值 +dP/dt均降低，同时左心室舒张末期压力显著升高，这些结果证明了这一点。氟司喹南（0.9毫克/千克，静脉注射）使心输出量增加28%，平均Vcf增加44%，峰值 +dP/dt增加24%，而全身总阻力降低32%，左心室压力衰减时间常数降低22%，左心室舒张末期压力降低18%。此外，氟司喹南显著降低了左心室后负荷的脉动成分（即特征阻抗降低11%，动脉波反射系数降低45%）。因此，氟司喹南不仅发挥了正性肌力作用，还发挥了正性松弛作用，同时显著降低了左心室后负荷的脉动和稳定成分，有助于改善急性心力衰竭时的左心室泵功能。
