Interaction of "supplementary" scintigraphic indicators of ischemia and stress electrocardiography in the diagnosis of multivessel coronary disease.

Lung uptake, ventricular cavitary dilation and basal myocardial uptake represent abnormalities that have been associated with myocardial ischemia on stress thallium-201 images, but that are supplementary to the conventional assessment of perfusion distribution. These "supplementary" indicators of ischemia were related to the coronary distribution of perfusion abnormalities, the results of electrocardiographic stress testing and to the findings on coronary angiography in 73 patients. Forty patients had multivessel coronary disease; 19 of these had three vessel disease. Perfusion abnormalities were seen in 39 of these 40 patients but were indicative of multivessel coronary disease in only 28 and of three vessel disease in only 6. However, supplementary indicators were present in 33 of 40 patients with multivessel disease and in 15 of 19 with three vessel disease. Furthermore, they were seen in 16 of 22 patients with multivessel disease in whom conventional perfusion abnormalities underestimated the extent of disease, but in only 4 of 12 patients in whom the extent of disease was overestimated. The presence of either perfusion abnormalities in a multivessel distribution or supplementary indicators identified 38 (95%) of 40 patients with multivessel disease. A markedly positive electrocardiographic treadmill test was a less sensitive indicator of multivessel disease, appearing in only 15 of 40 patients. However, it was present in only 4 of 33 patients without multivessel coronary disease and was more specific for that diagnosis than were supplementary scintigraphic indicators (88 versus 67%, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)