Abstract
Cigarette smoking is not only one of the most important risk factors for coronary artery disease, but also anginal attacks often occur during smoking. Coronary vasoconstriction is considered to be one of the mechanisms which cause anginal episodes.
Thirty patients with angina pectoris, 27 men and 3 women, were investigated. Group I comprised 22 patients with rest angina and group II consisted of 8 patients with effort angina.
Five minutes after smoking one cigarette, a first study of 201T1 myocardial SPECT was performed. Consecutively, after sublingual administration of isosorbide dinitrate, a second SPECT was done.
Most cases improved and it was recognized as positive when changes of localized perfusion defects were observed between both SPECTs. In the group I, 19 out of 22 patients (86%) were positive, but in the group II, 2 out of 8 (25%) were positive. The differences were statistically significant. (p<0.05)
By the examination of coronary angiography in 20 patients, the result of myocardial scintigraphy using cigarette smoking and isosorbide dinitrate seemed inversely proportional to the severity of narrowing of the coronary artery. In addition, background factors including risk factors were also compared for both groups. Because the result of this myocardial scintigraphy was positive in the rest angina group and in the group with minimal coronary arteriographic abnormalities, it suggests that myocardial scintigraphy using cigarette smoking and isosorbide dinitrate is useful as a non-invasive auxiliary diagnostic method to detect coronary spasm or coronary vasoconstriction-prone angina pectoris including silent myocardial ischemia.
