Alternative Mechanisms for Myocardial Ischemia in Syndrome X - New Diagnostic Markers

摘要: Exertional chest pain, positive exercise test responses and the presence of transient ST segment depression during Holier monitoring strongly suggest occurrence myocardial ischemia in syndrome X. However, carefully conducted studies have failed to show: (i) lactate production pacing [1,2]; (ii) increases pulmonary pressure spontaneous episodes [3]; (iii) abnormalities left ventricular wall motion as assessed by two-dimensional echocardiography dipyridamole testing [4]; (iv) decreases coronary sinus blood oxygen saturation [5] or pH [6] atrial pacing; (v) regional perfusion positron emission tomography [7]. Yet, a sizable proportion patients with X exhibit an alteration circulation suggested by: abnormally small increase flow response [8,9], particularly after ergonovine administration [10]; heterogeneous both at rest infusion [11,12] reduction thallium uptake [13-15].