下肢动脉球囊扩张成形术后血清β2微球蛋白变化及其对再狭窄或闭塞的预测作用

Predictive value of serum beta 2-microglobulin level for recurrent stenosis or occlusion in patients with lower limb ischemia undergoing percutaneous transluminal angioplasty

目的 研究下肢动脉球囊扩张成形术后血清β2微球蛋白的变化及其对术后再狭窄或闭塞的预测作用。方法 对东南大学附属中大医院介入与血管外科2009年3月至2010年10月间因下肢动脉狭窄或闭塞行介入治疗的54例患者进行随访，收集患者的一般资料，测定各时间点的血清β2微球蛋白水平。采用多普勒超声或CT血管造影明确有无复发的狭窄或闭塞。再狭窄或闭塞的相关因素先进行单因素分析，对于P〉0．20的因素再采用Cox回归模型进一步分析。结果 54例患者术后半年、1年和2年的累积初始通畅率分别为85％、69％和34％。术后血清β2微球蛋白水平逐渐降低，3个月后复发组的血清β2微球蛋白水平逐渐上升。Cox回归分析表明，血清β2微球蛋白水平为术后再狭窄或闭塞的独立危险因素（OR＝1．459，95％可信区间1．199～1．777；P=0．000）。ROC曲线显示血清β2微球蛋白水平预测再狭窄或闭塞的最佳临界点为3．2mg／L，预测的敏感性为95．7％、特异性为77．4％。结论 血清β2微球蛋白水平对术后再狭窄或闭塞有一定的预测作用，术后〉3．2mg／L的患者存在较高的复发的风险。

Objective To evaluate the predictive value of serum beta 2-microglobulin level for recurrent stenosis or occlusion in patient undergoing percutaneous transluminal angioplasty （PTA） for lower limb ischemia. Methods Between March 2009 and October 2010, 81 patients were admitted with a diagnosis of lower limb ischemia. Among them, 54 patients had a mean age of 64 ± 12 years. The baseline characteristics, stenting and post-procedure events were collected. And the serum level of beta 2-mieroglobulin was measured by dynamic timing nephelometry assay. Recurrent stenosis or occlusions were confirmed with color Doppler uhrasonography or CTA imaging. Cox regression univariate analysis was performed with variables with P value 〈 0. 20 to investigate the independent predictors of recurrent stenosis or occlusions. Receiver-operating characteristics curves （ROC） were constructed to evaluate the sensitivity and specificity of this model. Results The baseline characteristics were evenly distributed in two groups. Twenty-three patients （42. 5% ） were found to have recurrent stenosis or occlusions. The cumulative primary patency was 85%, 69% and 34% at Month 6, 12 and 24 respectively. The serum levels of beta 2-microglobulin decreased during a follow-up period of 3 months and then increased gradually in patients with recurrent stenosis or occlusion. Cox regression analysis identified the serum level of beta 2-microglobulin as an independent predictor of recurrent stenosis or occlusion （ Odds Ratio = 1. 459, 95% CI 1. 199 - 1. 777, P = 0. 000）. The area under the curve （ AUC ） of the serum level of beta 2-microglobulin was 0. 952 for recurrent stenosis or occlusion. And the sensitivity was 95.7% and the specificity 77.4% on a cut-off value 3.2 mg/L. Conclusion With a cut-off value 3.2 mg/L, the serum level of beta 2-microglobulin may be useful for the prediction of recurrent stenosis or occlusion in patients after lower limb PTA.