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The anomalous origin of the left coronary artery can lead to angina pectoris, acute myocardial infarction or even sudden death, especially during exercise. We present a patient in whom the anomalous origin of the left coronary artery is from the right sinus of Valsalva, crossing between the aorta and the pulmonary trunk and causing ischemic chest pain. The anomaly was verified by a Spiral CT, as the coronary angiographic findings were not conclusive, particularly regarding the left course in relation to the major arteries. We suggest that Spiral CT is useful for detecting this kind of anomaly, particularly in clarifying the relationship between the left main coronary artery and the major arteries.

Whether the presence of on-site coronary angiographic facilities (CAF) influences the use of invasive coronary procedures and the outcome of acute myocardial infarction in coronary care units was studied. A prospective survey was conducted early in 1992 when 1014 consecutive patients with acute infarction were admitted. Of them 707 (70%) were admitted to coronary care units of hospitals with, and 307 (30%) without CAF. Thrombolytic therapy was given to 46% in both groups. Those admitted to hospitals with CAF underwent more coronary angiographies (26%) and percutaneous transluminal angiography and/or coronary artery bypass grafting (12%) than those without CAF (10 and 5%, respectively--p < 0.005). In-hospital and 1-year mortality were 11 and 18% respectively in those with CAF, vs 10 and 11%, respectively, in those without CAF. All patients treated with a thrombolytic agent had similar mortality, unrelated to the availability of CAF. The survey showed that the availability of on-site coronary angiography facilities led to greater use of invasive coronary procedures in cases of acute myocardial infarction, but there was no significant difference in mortality.

Electrocardiographic recording during chest pain is usually performed for detection of myocardial ischemia and localization of the affected area. By analyzing changes in electrocardiograms recorded during chest pain, pathophysiological mechanisms of ischemia, prediction of coronary pathology, and the risk of evolution to myocardial infarction can be determined. Myocardial ischemia is caused by either an increase in O2 demand, reduction in coronary flow, or both. The former is manifested by tachycardia and in such patients measures should be taken to slow the heart rate. Patients with ischemia without tachycardia suffer from reduction of coronary flow and therapy should be aimed at increasing flow. We classify patients with ischemia but without tachycardia according to electrocardiographic patterns recorded during chest pain by precordial leads as follows: group 1, those with ST segment elevation and with positive T waves; group 2, ST segment depression and negative T waves; and group 3, ST depression and positive T waves. Group 1 patients have anterior wall ischemia and the left anterior descending artery is usually involved. They are possible candidates for coronary angiography. In group 2, the electrocardiographic changes reflect extensive subendocardial myocardial ischemia. We found severe coronary artery disease (LMCA or right main artery equivalent) in 69% of such patients, and the mortality in those with subsequent myocardial infarction was 77%, mainly due to pump failure. When this latter electrocardiographic pattern is found, intervention should be prompt, and surgery rather than angioplasty is usually necessary. Patients with ischemic ST depression maximal in V2-V3 should not be included in this group since these changes are reciprocal with posterolateral wall ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)