Kodera K, Kitamura M, Shibuya M, Kurihara H, Koyanagi H
Department of Cardiovascular Surgery, The Heart Institute of Japan, Tokyo Women's Medical University.
Artif Organs. 1998 Sep;22(9):803-7. doi: 10.1046/j.1525-1594.1998.06015.x.
Left dominant biventricular failure is a common type of heart failure after cardiac surgery. We developed a biventricular bypass (BVB) system for treatment of postcardiotomy ventricular failure, and we previously reported that the clinical results of the BVB system were superior to those obtained with venoarterial bypass (VAB). The purpose of this study was to evaluate the effect of the BVB system on left ventricular (LV) performance in comparison to that of VAB by means of the LV pressure-volume relationship (PVR). Eight adult mongrel dogs (14-21 kg) underwent VAB with right atrial and aortic cannulation. Left atrial cannulation was added for BVB, and both atrial drainage tubes were joined with a Y-shaped connector. The bypass flow was maintained at half of the baseline cardiac output (0.7-1.0 L/min), and the hemodynamic parameters were monitored. A high fidelity microtip catheter and a conductance catheter were used to evaluate LV function. The slope of the LV end-systolic pressure-volume relation (Emax), the slope of the LV end-systolic pressure-stroke-volume relation (Ea), the LV stroke work (SW), LV potential energy (PE), LV pressure-volume area (PVA), the slope of the SW end-diastolic volume relation (PRSW), and an index of the LV energizing charge (ratio of PE/PVA) were assessed during transient occlusion of the inferior vena cava. LV contractility (Emax) showed no significant change during each experiment. Standardized LV work (PRSW) was reduced by BVB in comparison to the baseline and in comparison to VAB. The rate of LV energy charge (PE/PVA) significantly increased only during BVB. These results suggested that the BVB system might be an effective circulatory support for reducing LV work and improving the LV energizing charge in patients with severe heart failure after cardiac operation.
左优势型双心室衰竭是心脏手术后常见的一种心力衰竭类型。我们研发了一种双心室旁路（BVB）系统用于治疗心脏切开术后心室衰竭，并且我们之前报道过BVB系统的临床效果优于静脉 - 动脉旁路（VAB）。本研究的目的是通过左心室压力 - 容积关系（PVR）评估BVB系统与VAB相比对左心室（LV）功能的影响。八只成年杂种犬（14 - 21千克）接受了右心房和主动脉插管的VAB。为进行BVB增加了左心房插管，并且两根心房引流管通过一个Y形连接器连接。旁路流量维持在基线心输出量的一半（0.7 - 1.0升/分钟），并监测血流动力学参数。使用高保真微尖端导管和电导导管评估左心室功能。在下腔静脉短暂闭塞期间，评估左心室收缩末期压力 - 容积关系（Emax）的斜率、左心室收缩末期压力 - 搏出量关系（Ea）的斜率、左心室搏功（SW）、左心室势能（PE）、左心室压力 - 容积面积（PVA）、SW与舒张末期容积关系（PRSW）的斜率以及左心室能量负荷指数（PE/PVA比值）。在每个实验过程中，左心室收缩性（Emax）无显著变化。与基线相比以及与VAB相比，BVB使标准化左心室功（PRSW）降低。仅在BVB期间，左心室能量负荷率（PE/PVA）显著增加。这些结果表明，BVB系统可能是一种有效的循环支持手段，可降低心脏手术后严重心力衰竭患者的左心室负荷并改善左心室能量负荷。
