Division of Cardiology, Robert-Bosch-Krankenhaus, Auerbachstrasse 110, Stuttgart 70376, Germany.
Heart. 2010 Mar;96(5):372-9. doi: 10.1136/hrt.2009.174367. Epub 2009 Nov 23.
Perfusion cardiovascular magnetic resonance (CMR) has a high sensitivity for the detection of significant coronary artery disease (CAD). However, the specificity of this method is lower than its sensitivity. The reason for this observation is hitherto unclear and has been either explained by 'false-positive' results or by microvascular dysfunction in patients without CAD.
To evaluate whether pathological myocardial perfusion-CMR imaging in symptomatic patients without significant CAD is associated with coronary epicardial or microvascular dysfunction.
In this retrospective study, 42 patients who presented with unstable angina pectoris underwent (a) an adenosine-stress perfusion-CMR study; (b) coronary angiography; (c) intracoronary acetylcholine (ACh) testing following coronary angiography with exclusion of significant CAD. The CMR protocol comprised cine imaging followed by adenosine first-pass perfusion imaging and late gadolinium enhancement-CMR. Diagnostic left ventriculography and multiplane coronary angiography were performed before intracoronary ACh testing.
An adenosine-induced, reversible subendocardial perfusion defect was detected in 22/42 patients (52%) without significant CAD. Coronary epicardial vasospasm was detected in 10/42 patients (24%) while microvascular dysfunction was found in 20/42 patients (48%). Patients with a reversible stress-induced perfusion defect had significantly more often a pathological coronary epicardial or microvascular vasoreaction (20/22; 91%) during intracoronary ACh testing than those without a perfusion defect (10/20; 50%; p<0.01). Univariate correlation analyses revealed a substantial association between a pathological ACh-testing result and a perfusion defect in the antecedent CMR study (r= +0.45; p<0.01).
Reversible perfusion defects depicted by perfusion-CMR in patients without significant CAD are mostly due to coronary epicardial or microvascular dysfunction, and correct interpretation of such perfusion-CMR results may enable targeted treatment.
灌注心血管磁共振（CMR）对检测严重冠状动脉疾病（CAD）具有较高的敏感性。然而，该方法的特异性低于其敏感性。迄今为止，这种观察结果的原因尚不清楚，有人认为是“假阳性”结果所致，也有人认为是 CAD 患者的微血管功能障碍所致。
评估无症状 CAD 患者的病理性心肌灌注 CMR 成像是否与冠状动脉心外膜或微血管功能障碍有关。
在这项回顾性研究中，42 例不稳定型心绞痛患者接受了（a）腺苷负荷灌注 CMR 研究；（b）冠状动脉造影；（c）排除明显 CAD 后行冠状动脉造影后的冠状动脉内乙酰胆碱（ACh）测试。CMR 方案包括电影成像，随后进行腺苷首次通过灌注成像和晚期钆增强 CMR。在进行冠状动脉内 ACh 测试之前，进行了诊断性左心室造影和多平面冠状动脉造影。
在 42 例无明显 CAD 的患者中，22 例（52%）检测到腺苷诱导的可逆性心内膜下灌注缺损。42 例患者中，10 例（24%）检测到冠状动脉心外膜痉挛，20 例（48%）检测到微血管功能障碍。在冠状动脉内 ACh 测试中，具有可逆性应激诱导灌注缺损的患者发生病理性冠状动脉心外膜或微血管血管反应的几率明显更高（22/22；91%），而无灌注缺损的患者（10/20；50%）则明显更低（p<0.01）。单变量相关分析显示，在 CMR 研究中，冠状动脉内 ACh 测试的病理结果与灌注缺陷之间存在显著相关性（r=+0.45；p<0.01）。
在无明显 CAD 的患者中，灌注 CMR 显示的可逆性灌注缺损主要是由于冠状动脉心外膜或微血管功能障碍所致，对这种灌注 CMR 结果的正确解释可能有助于进行有针对性的治疗。
