Clinical implications of exercise-induced chest pain: comparison of patients with and without pathologic Q waves in coronary artery disease.
We attempted to determine whether exercise-induced silent myocardial ischemia has different clinical implications in patients with and without pathologic Q waves. We studied 152 patients (121 men and 31 women) who had ischemic ST depression (greater than or equal to 0.05 mV) during exercise tests and greater than or equal to 70% narrowing in the three major coronary arteries. According to the presence or absence of chest pain during exercise, they were divided into symptomatic patients and asymptomatic patients: 104 patients without pathologic Q waves (Q(-) group) and 48 patients with pathologic Q waves (Q(+) group). In the Q(-) group, symptomatic patients (n = 56) had a significantly greater number of leads showing ST depression (p less than 0.0002), a greater maximum voltage of ST depression (p less than 0.005), a higher incidence of negative U waves (p less than 0.001), and a poorer blood pressure response (p less than 0.005) than asymptomatic patients (n = 48). However, in the Q(+) group, there were no significant differences between symptomatic (n = 24) and asymptomatic patients (n = 24) with regard to these parameters. We concluded that symptomatic patients without pathologic Q waves had more severe ischemia. On the other hand, in patients with pathologic Q waves, the severity of myocardial ischemia in asymptomatic patients might be equal to that in symptomatic patients. Chest pain during exercise testing is not a good predictor of myocardial ischemia in patients with pathologic Q waves. The presence or absence of pathologic Q waves is an important factor in the analysis of exercise-induced myocardial ischemia.
Ozawa
T
T
First Department of Internal Medicine, Yamagata University School of Medicine, Japan.
Ikeda
K
K
Yamaki
M
M
Kubota
I
I
Tsuiki
K
K
Yasui
S
S
D002637:Chest Pain / Q000209:etiology* / Q000503:physiopathology; D003327:Coronary Disease / Q000175:diagnosis / Q000503:physiopathology*; D004562:Electrocardiography; D015444:Exercise; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male