1.5T无对比剂全心冠状动脉磁共振血管成像评估冠状动脉狭窄严重程度的临床价值

目的 评价无对比剂1.5T 磁共振自由呼吸全心冠状动脉成像(MRCA)对冠心病≥50%及≥70%冠状动脉狭窄的诊断性能。方法 前瞻性纳入41例冠心病拟行介入冠状动脉造影(ICA)的患者,行无对比剂1.5T 自由呼吸全心MRCA。同时判断是否存在≥50%及≥70%管腔狭窄,以ICA为参考标准评估诊断效能,比较两者的敏感性、特异性及诊断准确性。结果 41例患者均完成MRCA,平均扫描时间(10.1±2.2)min。MRCA诊断≥50%及≥70%冠状动脉狭窄的敏感性、特异性、准确性在患者水平分别为100%(95%CI:89%~100%)及82%(95%CI:63%~94%)、38%(95%CI:9%~76%)及54%(95%CI:25%~81%)、88%(95%CI:73%~95%)及73%(95%CI:57%~85%);在血管水平分别为95%(95%CI:87%~99%)及86%(95%CI:73%~95%)、58%(95%CI:45%~71%)及76%(95%CI:65%~85%)、78%(95%CI:69%~84%)及80%(95%CI:71%~86%)。 MRCA在血管节段水平诊断≥50%狭窄的敏感性明显高于诊断≥70%狭窄(97%比88%;χ ²=5.73,P=0.017),特异性明显低于诊断≥70%狭窄(86%比94%;χ ²=14.12,P<0.001)。结论 无对比剂1.5T自由呼吸全心MRCA诊断冠状动脉≥50%及≥70%狭窄均具有较高的敏感性及准确性。与诊断≥50%狭窄相比,MRCA诊断≥70%狭窄在血管节段水平的敏感性较低,特异性较高。

Clinical Value of 1.5-T Non-contrast Whole-heart Magnetic Resonance Coronary Angiography in Evaluating the Severity of Coronary Stenosis

Objective To evaluate the diagnostic performance of 1.5-T non-contrast free-breathing whole-heart magnetic resonance coronary angiography(MRCA)for≥50% and≥70% coronary artery stenosis in coronary artery disease(CAD).Methods Forty-one patients clinically scheduled for invasive coronary angiography(ICA)underwent 1.5-T non-contrast free-breathing whole-heart MRCA.The diagnostic performance for≥50% and≥70% stenosis was evaluated and compared using ICA as a reference standard.Results MRCA was completed in all the 41 patients with the total acquisition time of(10.1 ± 2.2)min.The sensitivity,specificity,and accuracy of MRCA for≥50% and≥70% stenosis were 100%(95% CI:89%-100%)and 82%(95%CI:63%-94%),38%(95%CI:9%-76%)and 54%(95%CI:25%-81%),and 88%(95%CI:73%-95%)and 73%(95%CI:57%-85%)on a per-patient basis,respectively;they were 95%(95%CI:87%-99%)and 86%(95%CI:73%-95%),58%(95%CI:45%-71%)and 76%(95%CI:65%-85%),and 78%(95%CI:69%-84%)and 80%(95%CI:71%-86%)on a per-vessel basis,respectively.The sensitivity of MRCA for≥50% stenosis was higher than that for≥70% stenosis(97%vs.88%,χ ²=5.73,P=0.017),and the specificity showed an opposite trend(86% vs. 94%,χ ²=14.12,P<0.001)on a per-segment basis.Conclusions The 1.5-T non-contrast whole-heart MRCA can detect both≥50% and≥70% coronary artery stenosis with high sensitivity and accuracy.MRCA showed lower sensitivity while higher specificity for≥70% stenosis than for≥50% stenosis on a per-segment basis.