双源CT在冠状动脉支架内再狭窄诊断中的价值

Value of detecting in-stent restenosis by dual source coronary computed tomography coronary angiography

目的 参照定量冠状动脉造影结果,评价双源CT在冠状动脉支架内再狭窄诊断中的价值.方法 对55例支架术后出现胸闷、胸痛的冠心病患者,在术后6～12个月行双源CT检查及定量冠状动脉造影.以定量冠状动脉造影结果为参照,评价双源CT诊断支架内再狭窄的真阳性、真阴性、假阳性、假阴性,并计算敏感性、特异性、阳性预测值、阴性预测值.分析心率、置人支架情况对双源CT诊断性能的影响.结果 55例患者共置入89枚支架,其中31.5%（28/89）的支架经冠状动脉造影证实发生支架内再狭窄.双源CT诊断支架内再狭窄的敏感性、特异性、阳性预测值、阴性预测值分别为89%、87%、76%和95%.双源CT诊断心率＜70次/min及≥70次/min患者支架内再狭窄的敏感性（94%比82%）、特异性（88%比90%）、阳性预测值（76%比75%）、阴性预测值（97%比93%）差异无统计学意义（P＞0.05）.双源CT诊断重叠支架、分叉部位支架与单支架再狭窄的敏感性（84%比100%）、特异性（81%比96%）、阳性预测值（70%比90%）和阴性预测值（91%比100%）差异无统计学意义（P＞0.05）.双源CT诊断直径≥3.50 mm支架、直径3.00 mm支架和直径≤2.75mm支架发生再狭窄的特异性（分别为100%、80%和66%,P＜0.05）和阳性预测值（分别为100%、95%和53%,P＜0.05）差异有统计学意义.结论 双源CT对大直径支架的再狭窄有较好的诊断性能,且不受心率和支架分布情况的影响.

Objective To evaluate the value of dual source computed tomography coronary angiography（DSCT-CA）on detecting in-stent restenosis（〉 50% luminal narrowing）in symptomatic patients referred for quantitative coronary angiography（QAC）. Methods Fifty five patients（43 males）with chest pain after coronary stent implantation within 6 - 12 months were evaluated by DSCT-CA and QAC. The sensitivity, specificity, positive predictive value（PPV）and negative predictive value（NPV）of DSCT-CA were calculated using coronary angiography as gold standard. Results Eighty nine stents were implanted.In-stent restenosis was evidenced in 28 stents（31.5%）by QAC. The sensitivity, specificity PPV and NPV of DSCT-CA for the diagnosis of in-stent restenosis was 89%, 87%, 76% and 95%, respectively.Diagnostic efficiency was not affected by heart rate and the sensitivity was 0. 94 vs. 0.82, the specificity 0. 88 vs. 0. 90, the PPV 0. 76 vs. 0.75 and the NPV 0. 97 vs. 0. 93（all P 〉 0. 05）between patients with heart rate 〈70 beats/min and patients with heart rate≥70 beats/min. The sensitivity（84% vs. 100%）,specificity（81% vs. 96%）, PPV（70% vs. 90%）and NPV（91% vs. 100%）were similar between overlapping or bifurcations stents and single stents. The specificity（100% vs. 80% vs. 66%）and PPV （100% vs. 95% vs. 53%）were significantly higher in the groups with stents ≥3.50 mm, stents 3.00 mm than in stents ≤2. 75 mm（both P 〈 0. 05）. Conclusion Diagnostic efficiency of in-stent restenosis with DSCT-CA in the large diameter stent is better than in the small diameter stent and the diagnosis efficacy is not affected by heart rate and stent distribution.