Significance of ST segment depression in exercise-induced supraventricular extrasystoles.
The significance of exercise-induced ST segment depression in supraventricular extrasystoles (STx), in the preceding sinus beats (STs), as well as the significance of the difference between the two of them (STx-s), was studied in 96 patients with angiographically documented coronary artery disease (CAD) (group A)--34 with myocardial infarction (group A1) and 62 without (group A2)--compared to 37 subjects with normal coronary arteries (group B). All patients had supraventricular extrasystoles during exercise testing, the results of which were positive in 72 (75%) patients in group A and six (16.2%) patients in group B (sensitivity 75%, specificity 84%). Among patients in group A STx was greater than STs (1.7 +/- 1.0 vs 1.2 +/- 0.8 mm; p less than 0.001), and STx-s was positive in 70 (sensitivity 73%), whereas in group A2 there were 44 patients with these values (sensitivity 71%). Among patients in group B no statistically significant difference was found between STx and STx (0.4 +/- 0.6 vs 0.6 +/- 0.7 mm; p = NS), whereas STx-s was positive in three (specificity 92%). Among the 24 patients in group A with false negative results of exercise tests, 15 (62.5%) had a positive STx-s, whereas of the 17 patients in group A2 with false negative results, 10 (58.8%) had a positive STx-s. Among the six patients in group B with false positive exercise test results, the STx-s was positive in two.(ABSTRACT TRUNCATED AT 250 WORDS)
Michaelides
A P
AP
University Cardiac Unit, Hippokrateion Hospital, Athens, Greece.
Vyssoulis
G P
GP
Triposkiadis
F K
FK
Papadakis
P V
PV
Kourouklis
K V
KV
Toutouzas
P K
PK
D005117:Cardiac Complexes, Premature / Q000209:etiology / Q000503:physiopathology*; D003327:Coronary Disease / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D004562:Electrocardiography; D005080:Exercise Test / Q000592:standards; D005260:Female; D006352:Heart Ventricles; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity