Carpenter J P, Baum R A, Holland G A, Barker C F
Department of Surgery, University of Pennsylvania School of Medicine, Philadelphia.
J Vasc Surg. 1994 Dec;20(6):861-9; discussion 869-71. doi: 10.1016/0741-5214(94)90222-4.
Magnetic resonance angiography (MRA) is a developing technique that provides arteriograms without the risks associated with iodinated contrast and arterial puncture or the expense of hospitalization. Prior reports have demonstrated the accuracy of peripheral vessel MRA for evaluation of the aorta through pedal vessels. This study sought to determine whether vascular reconstructions could be planned and accomplished on the basis of MRA alone.
Eighty consecutive candidates for bypass with ischemic rest pain or tissue loss were studied with preoperative outpatient MRA of the juxtarenal aorta through the foot. Confirmation of MRA findings was provided by intraoperative intraarterial pressure measurements for proximal vessels and postbypass arteriography for the runoff. Life-table analysis of graft patency and limb salvage was performed.
Two patients could not tolerate MRA and required contrast arteriography, but all others underwent reconstructive procedures on the basis of MRA alone (11 aortobifemoral, 67 infrainguinal). Intraoperative findings regarding suitability of inflow and outflow vessels confirmed the accuracy of the MRAs in every case. MRA indicated that none of the patients undergoing infrainguinal bypass had significant inflow occlusive disease, and this was confirmed at operation with pressure measurements of inflow vessels that were always within 10 mm Hg (peak systolic) of systemic pressure. The results of intraoperative completion arteriography and preoperative MRAs were identical for all but two patients who had minor discrepancies. All aortobifemoral reconstructions remained patent, and all limbs remained intact. The infrainguinal reconstructions had an 84% limb salvage rate and 78% primary graft patency rate at 21 months. Comparison of charges for patients undergoing preoperative MRA versus contrast angiography showed a cost savings of $1288 for each patient treated with preoperative MRA alone.
MRA is a noninvasive, cost-effective outpatient imaging technique that, if properly performed and interpreted, is sufficient for planning peripheral bypass procedures. Its use may supplant contrast arteriography in many patients.
磁共振血管造影(MRA)是一项不断发展的技术,它能提供动脉造影,且不存在与碘化造影剂及动脉穿刺相关的风险,也无需住院费用。先前的报告已证实外周血管MRA在通过足部血管评估主动脉方面的准确性。本研究旨在确定是否仅基于MRA就能规划并完成血管重建。
连续80例因缺血性静息痛或组织缺损而需行旁路手术的患者接受了术前门诊经足部对肾旁主动脉的MRA检查。通过术中对近端血管进行动脉内压力测量以及旁路术后对流出道进行动脉造影来证实MRA检查结果。对移植物通畅率和肢体挽救情况进行寿命表分析。
2例患者无法耐受MRA,需要进行造影剂动脉造影,但其他所有患者仅基于MRA就接受了重建手术(11例主-双股动脉旁路移植术,67例腹股沟下旁路移植术)。术中关于流入和流出血管适宜性的发现证实了每种情况下MRA的准确性。MRA显示,接受腹股沟下旁路移植术的患者均无明显的流入道闭塞性疾病,术中对流入血管的压力测量证实了这一点,其压力始终在系统压力的10 mmHg(收缩压峰值)范围内。除2例有轻微差异的患者外,术中完成动脉造影和术前MRA的结果相同。所有主-双股动脉重建移植物均保持通畅,所有肢体均保持完好。腹股沟下重建术在21个月时的肢体挽救率为84%,原发性移植物通畅率为78%。对接受术前MRA与造影剂血管造影的患者费用进行比较,结果显示仅接受术前MRA治疗的每位患者节省费用1288美元。
MRA是一种无创、性价比高的门诊成像技术,如果操作和解读得当,足以用于规划外周旁路手术。在许多患者中,它的应用可能会取代造影剂动脉造影。