Ando M, Imai Y, Takanashi Y, Hoshino S, Seo K, Terada M
Heart Institute of Japan, Tokyo Women's Medical College, Japan.
Ann Thorac Surg. 1997 Jul;64(1):154-8. doi: 10.1016/s0003-4975(97)00278-6.
External conduits used for the repair of congenital heart diseases having discontinuity between the pulmonic ventricle and the pulmonary artery still carries a high risk of reoperation. Between June 1983 and June 1992, handmade equine pericardial conduit with fabricated trileaflet valve had been the conduit of choice in our institute. The aim of this study is to clarify the temporal sequence of conduit obstruction in this material and to formulate the optimal surgical strategies for this disease entity.
One hundred forty-three patients have undergone extracardiac conduit repair using this conduit. Postoperative catheterization performed within 2 months showed pulmonary to systemic ventricular systolic pressure ratio of 0.57 +/- 0.17 with the pressure gradient between pulmonic ventricle and pulmonary artery of 21.1 +/- 17.2 mm Hg. In 63 patients among the survivors, a series of Doppler two-dimensional echocardiographic images could be clearly obtained.
Moderate-to-severe degree of pulmonary insufficiency represented only 3.2% of all cases within 3 months, which rapidly increased to 14.3% at 1 to 3 years and 32.8% at 3 to 5 years. However, the rate of increase of pulmonary insufficiency diminished beyond 5 years with 34.9% at 5 to 7 years and 40.0% at 7 to 9 years. Estimated pressure gradient calculated by Bernoulli's equation applied in the same patient subset was 4.1 +/- 7.9 mm Hg within 3 months, which progressively increased to 7.1 +/- 11.8 mm Hg at 1 to 3 years, 21.0 +/- 24.0 mm Hg at 3 to 5 years, 40.2 +/- 25.9 mm Hg at 5 to 7 years, and 71.3 +/- 34.0 mm Hg at 7 to 9 years. Among patients with a pressure gradient across the conduit of more than 40 mm Hg at follow-up catheterization, the primary cause of the obstruction was attributed to degeneration of the valve in 7 patients, whereas sternal compression was strongly suspected as the primary cause in the other 8 patients. Intimal peel was not obvious in the excised specimens.
Degeneration of the valve in the equine pericardial conduit became prominent at 3 to 5 years after the operation, whereas the pressure gradient across the conduit continued to progress thereafter. A thick and hardened valve from degeneration and varying degrees of external compression by the sternum were delineated at the site of stenosis.
用于修复先天性心脏病（肺动脉心室与肺动脉之间存在连续性中断）的外部管道再次手术风险仍然很高。1983年6月至1992年6月期间，手工制作的带有定制三叶瓣的马心包管道一直是我们研究所的首选管道。本研究的目的是阐明这种材料中管道梗阻的时间顺序，并制定针对该疾病实体的最佳手术策略。
143例患者接受了使用这种管道的心脏外管道修复术。术后2个月内进行的导管检查显示，肺循环与体循环心室收缩压之比为0.57±0.17，肺动脉心室与肺动脉之间的压力梯度为21.1±17.2毫米汞柱。在幸存者中的63例患者中，可以清晰地获得一系列多普勒二维超声心动图图像。
轻度至重度肺动脉瓣关闭不全在3个月内仅占所有病例的3.2%，在1至3年时迅速增至14.3%，在3至5年时增至32.8%。然而，5年后肺动脉瓣关闭不全的增加速率减缓，在5至7年时为34.9%，在7至9年时为40.0%。应用伯努利方程在同一患者亚组中计算的估计压力梯度在3个月内为4.1±7.9毫米汞柱，在1至3年时逐渐增至7.1±11.8毫米汞柱，在3至5年时为21.0±24.0毫米汞柱，在5至7年时为40.2±25.9毫米汞柱，在7至9年时为71.3±34.0毫米汞柱。在随访导管检查中，导管两端压力梯度超过40毫米汞柱的患者中，7例梗阻的主要原因归因于瓣膜退变，而另外8例患者强烈怀疑主要原因是胸骨压迫。切除标本中内膜剥离不明显。
马心包管道中的瓣膜退变在术后3至5年变得明显，而此后导管两端的压力梯度持续进展。在狭窄部位可看到因退变而增厚变硬的瓣膜以及胸骨不同程度的外部压迫。
