CORONARY FLOW RESERVE IN DILATED CARDIOMYOPATHY

在大多数扩张型心肌病患者中 病因尚不清楚。许多扩张型心肌病患者 尽管血管造影正常，但仍主诉心绞痛型疼痛 心外膜冠状动脉。以检查异常现象是否 冠脉血流中存在扩张型心肌病26例 扩张型心肌病和正常的心外膜冠状动脉 动脉，其中12人有频繁的胸痛病史， 接受了心脏大静脉血流的测量和 静息和起搏至心率时的心肌代谢 150美元。在给麦角新碱后的起搏过程中，所有 有胸痛病史的12名患者经历了典型的 疼痛。与没有胸痛的患者相比，他们的冠状动脉 血流量较低，冠状动脉阻力较高，并有增加 心肌氧摄取提示心肌缺血。 此外，左心室的增加幅度更大。 这组中的充填压力。没有明显的变化 经冠状动脉造影术显示心电图或心外膜冠脉内径。 双嘧达莫0.5-0.75 mg静脉注射给药 20名患者证明，这7名患者有 心绞痛也有跨壁冠状动脉血流障碍。 与13例无胸痛的患者进行比较。因此， 有扩张型心肌病和胸痛病史的患者 可能冠状动脉血管扩张剂储备有限，特别是在 血管收缩刺激。这是否有助于 扩张型心肌病的心肌损害或是 一种无关病因的副现象，有待于 下定决心。

In the majority of patients with dilated cardiomyopathy the etiology is unknown. Many patients with dilated cardiomyopathy complain of anginal-type pain despite angiographically normal epicardial coronary arteries. To examine whether abnormalities in coronary flow exist in dilated cardiomyopathy, 26 patients with dilated cardiomyopathy and normal epicardial coronary arteries, 12 of whom had frequent chest pain by history, underwent measurement of great cardiac vein flow and myocardial metabolism at rest and during pacing to a heart rate of 150. During pacing following administration of ergonovine, all 12 patients with a history of chest pain experienced their typical pain. Compared to patients without chest pain, their coronary flow was lower and coronary resistance higher, with increased myocardial oxygen extraction suggestive of myocardial ischemia. Additionally, there was a greater increase in left ventricular filling pressures in this group. There was no significant change in EKG or epicardial coronary luminal diameter by angiography. Administration of dipyridamole 0.5 to 0.75 mg intravenously to 20 patients demonstrated that those 7 patients with a history of angina pectoris also had impairment in transmural coronary flow reserve compared to the 13 patients without chest pain. Thus, patients with dilated cardiomyopathy and chest pain by history may have limited coronary vasodilator reserve, especially after vasoconstrictor stimulus. Whether this contributes to myocardial damage in dilated cardiomyopathy or is an epiphenomenon of an unrelated etiology, remains to be determined.