ABNORMAL BRONCHIAL AIRWAY FUNCTION IN PATIENTS WITH MICROVASCULAR ANGINA

我们之前已经证明，血管扩张储备 麦角新碱治疗后冠脉微循环减少 胸痛，尽管在缺席时冠状动脉造影正常 心外膜痉挛，并称之为微血管心绞痛。 随后，我们发现前臂对缺血的血流反应有限。 血管和食道运动异常，表明广泛的 肌张力紊乱。 因为呼吸困难在这些患者中很常见，而且似乎 与心肌缺血的严重程度不成比例，我们研究 气道流量(FEV1)以确定支气管平滑肌是否 微血管心绞痛也异常。在11例患者中测量了FEV1 微血管心绞痛患者增量治疗前后的对比研究 服用乙酰甲胆碱，并与正常对照组比较。 乙酰甲胆碱导致FEV1较基线下降20% 11例患者服用乙酰甲胆碱，剂量为81加或减71 累计单位。相比之下，12名对照组患者中只有2名 乙酰甲胆碱剂量为179正或负时，FEV1下降20% 累计单位p小于.001)显著的响应率 低于微血管心绞痛患者(p<0.02)。 因此，微血管心绞痛患者的呼吸困难可能是由于 支气管平滑肌活动亢进。这些结果进一步 表示更普遍的血管性和非血管性疾病 在这种综合征中，平滑肌功能正常。

We have previously demonstrated that the vasodilator reserve of the coronary microcirculation is reduced after ergonovine in patients with chest pain despite normal coronary angiograms in the absence of epicardial spasm, and term this disorder microvascular angina. We subsequently found limited flow response to ischemia in forearm vessels and abnormal esophageal motility, suggesting a widespread disorder of smooth muscle tone. Because dyspnea is common in these patients and seems disproportionate to the severity of myocardial ischemia, we studied airway flow (FEVl) to determine whether bronchial smooth muscle is also abnormal in microvascular angina. FEV1 was measured in 11 patients with microvascular angina before and after incremental doses of methacholine and compared to normal controls. Methacholine caused a 20% decrease in FEVl from baseline in 8 of 11 patients at a methacholine dose of 81 plus or minus 71 cumulative units. In contrast, only 2 of 12 control patients had a 20% decrease in FEV1 at a methacholine dose of 179 plus or minus cumulative units p less than .001) a response rate significantly less than patients with microvascular angina (p less than .02). Thus, dyspnea in microvascular angina patients may be due to hyperactivity of bronchial smooth muscle. These results further indicate a more generalized disorder of vascular and nonvascular smooth muscle function in this syndrome.