Montorsi P, Manfredi M, Loaldi A, Fabbiocchi F, Polese A, de Cesare N, Bartorelli A, Guazzi M D
Istituto di Cardiologia, University of Milan, Italy.
Am J Cardiol. 1989 May 15;63(17):1198-202. doi: 10.1016/0002-9149(89)90178-1.
To test whether calcium channel blockade plays a similar role in the coronary vasomotion of patients with syndrome X (n = 29) and patients with Prinzmetal's angina pectoris (n = 12), quantitative angiography was used to evaluate the effect of nifedipine (10 mg, sublingually) on the lumen diameter of proximal, mid and distal thirds of normal epicardial branches. The main differences in the coronary vasomotor reaction were uniform vasodilatation in Prinzmetal's angina and a variable response to syndrome X, and a greater increase in the coronary lumen in patients with Prinzmetal's angina as compared with those with syndrome X who showed vasodilatation. The variable response in syndrome X was not related to changes in diastolic pressure and cardiac output. Patients showing coronary constriction were those who responded to nifedipine with a higher degree of tachycardia, which might suggest a neural participation in the paradoxic reaction to this drug. In the Prinzmetal group, on the contrary, at a similar heart rate increase the pattern was invariably vasodilatation. Thus, calcium ions appear to have a different role in the coronary smooth muscle contractility of the 2 series of patients; in fact, in Prinzmetal's angina nifedipine relaxed the coronary arteries to a greater degree and made them unresponsive to stimuli that were still able to cause vasoconstriction in patients with syndrome X.
为了检验钙通道阻滞剂在X综合征患者（n = 29）和变异型心绞痛患者（n = 12）的冠状动脉血管运动中是否发挥类似作用，采用定量血管造影术评估硝苯地平（10毫克，舌下含服）对正常心外膜分支近端、中段和远端三分之一管腔直径的影响。冠状动脉血管运动反应的主要差异在于，变异型心绞痛表现为均匀的血管扩张，而X综合征的反应则各不相同；与表现为血管扩张的X综合征患者相比，变异型心绞痛患者的冠状动脉管腔增大更为明显。X综合征的不同反应与舒张压和心输出量的变化无关。出现冠状动脉收缩的患者是那些对硝苯地平有更高程度心动过速反应的患者，这可能提示神经参与了对该药物的反常反应。相反，在变异型心绞痛组中，在心率增加相似的情况下，模式总是血管扩张。因此，钙离子在这两组患者的冠状动脉平滑肌收缩性中似乎发挥着不同的作用；事实上，在变异型心绞痛中，硝苯地平能更大程度地舒张冠状动脉，并使其对仍能导致X综合征患者血管收缩的刺激无反应。
