Bandyk D F, Schmitt D D, Seabrook G R, Adams M B, Towne J B
Department of Surgery, Medical College of Wisconsin, Milwaukee.
J Vasc Surg. 1989 Feb;9(2):286-96.
Implementation of a protocol that monitored in situ saphenous vein bypass hemodynamics for low-flow states provided insight into the pathophysiologic characteristics and time course of graft failure. From 1981 to 1988, 250 in situ bypasses to popliteal (n = 83) or tibial (n = 167) arteries were performed in 231 patients. Indications for operation included critical limb ischemia in 232 cases (93%), popliteal aneurysm in 11 cases (4%), and disabling claudication in seven cases (3%). Arterial pressure measurements, continuous-wave Doppler spectral analysis, and duplex ultrasonography were used to assess patency, detect hemodynamic changes indicative of graft stenosis, and localize anatomic hemodynamic changes indicative of graft stenosis. Seventy grafts with correctable anatomic lesions (retained venous valves, graft stenosis, arteriovenous fistula, native vessel atherosclerosis) that decreased graft blood flow or ankle arterial pressure or both were identified. Correction of vein conduit or anastomotic lesions comprised 73 (77%) of the 95 revisions performed. Vein-patch angioplasty of a stenosis was the most common secondary operation performed. Graft revision was highest in the perioperative period (10% at 30 days), decreased to 7% per 6-month interval until 18 months, and was 3% per year thereafter. The primary patency rate of grafts not identified to have a correctable lesion was 86% at 4 years, a level similar to the secondary patency of 81% for grafts requiring one or multiple revisions. The surveillance protocol identified grafts with correctable lesions before thrombosis thereby permitting elective revision of patent grafts. Hemodynamic studies confirmed that a frequent mechanism of late failure of grafts was the development of a low-flow state produced by lesions not amenable to revision.
实施一项监测原位隐静脉旁路血流动力学低流量状态的方案，有助于深入了解移植物失败的病理生理特征和时间进程。1981年至1988年期间，对231例患者进行了250次原位旁路移植术，移植至腘动脉（83例）或胫动脉（167例）。手术指征包括232例（93%）严重肢体缺血、11例（4%）腘动脉瘤和7例（3%）致残性跛行。采用动脉压测量、连续波多普勒频谱分析和双功超声检查来评估通畅情况、检测提示移植物狭窄的血流动力学变化以及定位提示移植物狭窄的解剖学血流动力学变化。共识别出70例存在可纠正解剖病变（保留静脉瓣膜、移植物狭窄、动静脉瘘、自体血管动脉粥样硬化）的移植物，这些病变导致移植物血流量或踝动脉压或两者均降低。在进行的95次翻修手术中，73次（77%）是对静脉管道或吻合口病变进行纠正。对狭窄进行静脉补片血管成形术是最常见的二次手术。移植物翻修在围手术期最高（30天时为10%），每6个月间隔降至7%，直至18个月，此后每年为3%。未发现有可纠正病变的移植物4年时的一期通畅率为86%，这一水平与需要一次或多次翻修的移植物81%的二期通畅率相似。监测方案在血栓形成前识别出有可纠正病变的移植物，从而允许对通畅的移植物进行择期翻修。血流动力学研究证实，移植物晚期失败的常见机制是由无法进行翻修的病变导致低流量状态的出现。
