Chen E P, Bittner H B, Davis R D, Van Trigt P
Department of Surgery, Duke University Medical Center, Durham, NC, USA.
J Heart Lung Transplant. 1998 Jul;17(7):669-78.
Right ventricular failure remains an important cause of early morbidity and death after heart transplantation and is commonly related to preexistent recipient chronic pulmonary hypertension, which occurs as a result of long-standing congestive heart failure. In this study, the hemodynamic and inotropic effects of milrinone were assessed after bicaval heart transplantation in the setting of monocrotaline pyrrole-induced recipient chronic pulmonary hypertension.
Twenty dogs were used for 10 successfully completed transplantation experiments. Recipient animals underwent right atrial injection of 3 mg/kg monocrotaline pyrrole 4 months before transplantation. Hemodynamic and functional data were taken 1 hour after termination of cardiopulmonary bypass and after milrinone infusion. Myocardial function was assessed with load-insensitive means (preload-recruitable stroke work) and pulmonary vascular impedance was calculated with Fourier analysis.
At the time of transplantation, before cardiopulmonary bypass, pulmonary hemodynamic indexes in recipient animals were significantly increased when compared with donors and were further significantly increased after cardiopulmonary bypass. Two animals died after transplantation as a result of acute right ventricular failure. In surviving animals milrinone infusion led to significant increases in right ventricular function, which occurred in association with significant improvements in pulmonary vascular impedance and transpulmonary efficiency.
In the setting of monocrotaline pyrrole-induced recipient pulmonary hypertension, milrinone was associated with significant improvements in pulmonary vascular impedance, right ventricular function, and transpulmonary efficiency. These data suggest that milrinone is an effective means to improve right ventricular dysfunction and pulmonary vascular efficiency after bicaval heart transplantation in the setting of recipient chronic pulmonary hypertension.
右心室衰竭仍然是心脏移植后早期发病和死亡的重要原因，通常与受体先前存在的慢性肺动脉高压有关，这种慢性肺动脉高压是由长期充血性心力衰竭引起的。在本研究中，评估了在单氰胺吡咯诱导的受体慢性肺动脉高压情况下，双腔心脏移植后米力农的血流动力学和正性肌力作用。
20只狗用于10项成功完成的移植实验。受体动物在移植前4个月经右心房注射3mg/kg单氰胺吡咯。在体外循环结束后1小时和米力农输注后采集血流动力学和功能数据。用负荷不敏感方法（前负荷可募集搏功）评估心肌功能，并用傅里叶分析计算肺血管阻抗。
在移植时，体外循环前，受体动物的肺血流动力学指标与供体相比显著升高，体外循环后进一步显著升高。2只动物在移植后因急性右心室衰竭死亡。在存活的动物中，米力农输注导致右心室功能显著增加，同时肺血管阻抗和跨肺效率也有显著改善。
在单氰胺吡咯诱导的受体肺动脉高压情况下，米力农与肺血管阻抗、右心室功能和跨肺效率的显著改善有关。这些数据表明，米力农是改善受体慢性肺动脉高压情况下双腔心脏移植后右心室功能障碍和肺血管效率的有效手段。
