Dimitrow Pawel Petkow, Galderisi Maurizio, Rigo Fausto
2nd Department of Cardiology, Collegium Medicum, Jagiellonian University, Cracow, Poland.
Cardiovasc Ultrasound. 2005 Aug 4;3:18. doi: 10.1186/1476-7120-3-18.
Transthoracic Doppler echocardiographic-derived coronary flow reserve is an useful hemodynamic index to assess dysfunction of coronary microcirculation. Isolated coronary microvascular abnormalities are overt by reduced coronary flow reserve despite normal epicardial coronary arteries. These abnormalities may occur in several diseases (arterial hypertension, diabetes mellitus, hypercholesterolemia, syndrome X, aortic valve disease, hypertrophic cardiomyopathy and idiopathic dilated cardiomyopathy). The prognostic role of impaired microvascular coronary flow reserve has been shown unfavourable especially in hypertrophic or idiopathic dilated cardiomyopathies. Coronary flow reserve reduction may be reversible, for instance after regression of left ventricular hypertrophy subsequent to valve replacement in patients with aortic stenosis, after anti-hypertensive treatment or using cholesterol lowering drugs. Coronary flow reserve may increase by 30% or more after pharmacological therapy and achieve normal level >3.0. In contrast to other non invasive tools as positron emission tomography, very expensive and associated with radiation exposure, transthoracic Doppler-derived coronary flow reserve is equally non invasive but cheaper, very accessible and prone to a reliable exploration of coronary microvascular territories, otherwise not detectable by invasive coronary angiography, able to visualize only large epicardial arteries.
经胸多普勒超声心动图测定的冠状动脉血流储备是评估冠状动脉微循环功能障碍的有用血流动力学指标。尽管心外膜冠状动脉正常，但冠状动脉血流储备降低可显示孤立的冠状动脉微血管异常。这些异常可能发生在多种疾病中（动脉高血压、糖尿病、高胆固醇血症、X综合征、主动脉瓣疾病、肥厚型心肌病和特发性扩张型心肌病）。微血管冠状动脉血流储备受损的预后作用已显示不佳，尤其是在肥厚型或特发性扩张型心肌病中。冠状动脉血流储备降低可能是可逆的，例如在主动脉瓣狭窄患者瓣膜置换后左心室肥厚消退后、抗高血压治疗后或使用降胆固醇药物后。药物治疗后冠状动脉血流储备可能增加30%或更多，并达到>3.0的正常水平。与其他非侵入性工具如正电子发射断层扫描相比，正电子发射断层扫描非常昂贵且与辐射暴露相关，经胸多普勒测定的冠状动脉血流储备同样是非侵入性的，但更便宜、更容易获得，并且易于对冠状动脉微血管区域进行可靠的探查，否则通过侵入性冠状动脉造影无法检测到，侵入性冠状动脉造影只能显示大的心外膜动脉。
