Correlation of electrocardiographic studies and arteriographic findings with angina pectoris.

SUMMARY The relationships among angina pectoris, stress tests, and arteriography are complex. The majority of patients with angina pectoris can be adequately diagnosed by a careful history. Considerable attention to detail and repeated questioning is often necessary before the pain syndrome can be accurately classified. The resting electro-cardiogram is of limited value in the diagnosis despite the fact that there is a high positive correlation between abnormal ST-T changes on the electrogram and significant obstructive lesions on coronary arteriograms. The value of the electrocardio-gram is enhanced, and its specifiicity and sensitivity increased, when used in combination with exercise stress. The lowest error percentage is achieved by utilizing rate-standardized exercise tests and multiple leads with loads that produce heart rate responses of 80-90% of the expected maximum. Coronary arteriography gives the most specific anatomic information in patients with ischemic cardiac pain but will not directly disclose the cause of the pain. This fact assumes considerable importance when the pain has atypical features or when the patient is in the age group that has a high prevalence of coronary atherosclerosis. Similarly, the presence of past myo-cardial infarction is likely to be associated with obstructive disease, regardless of the cause of the patient's current symptoms. The exact role of lipid and other metabolic abnormalities in producing coronary arteriographic changes in the absence of symptoms needs further clarification, although the available data suggest that marked elevations in lipid fractions are frequently associated with atherosclerotic change, regardless of symptoms. Finally, the data imply that the anatomic abnormalities and functional consequences of the coronary atherosclerotic process are more important predictors of the patient's course than any specific symptomatic expression such as angina pectoris. A NGINA PECTORIS is a clinical term and denotes a symptom complex. As ordinarily used, there is lack of precision in the definition of the term "angina pectoris" which poses a fundamental difficulty in approaching the problem of correlating the electrocardio-graphic findings and arteriographic observations. It is useful to consider ischemic myocardial states as a spectrum, or set, with angina pectoris a subset of the spectrum as is shown in the Venn diagram (fig. 1). Ischemia from obstructive coronary disease and ische-mia without coronary obstruction are disjoint sets within the spectrum. Ischemia due to obstructive coronary disease is the major subset of the ischemic rnyocardial spectrum. The subsets of myocardial infarction and angina pectoris are composed primarily of patients with obstructive coronary disease …