Persistent painless ST-segment depression after exercise testing and the effect of age.
The relation between the duration of ischemic ST-segment depression (1 mm or more 60 ms after the J point) and the clinical awareness of chest pain was studied in 31 patients (aged 39-73 years) undergoing symptom-limited, graded treadmill exercise testing. The response of these patients to nitrate therapy (spray or sublingual tablet) given immediately on cessation of exercise was also studied. During exercise, angina pectoris appeared at an estimated workload of 4.6 +/- 2.2 metabolic equivalents (METS) (mean +/- SD), and pathological ST-segment depression at 4.9 +/- 1.9 METS (p = NS.) On cessation of exercise, angina disappeared after 3.0 +/- 1.9 min, but ST-segment depression persisted for more than twice as long (6.6 +/- 4.1 min) (p less than 0.0001). The ratio of time to ST-segment recovery/time to relief of pain (a quantitative measure of silent ischemia during recovery) increased with age (r = 0.49, p = 0.002), and in 16 patients over 60 years of age was higher than in 15 younger patients (3.6 +/- 2.5 vs. 2.1 +/- 1.4) (p less than 0.04). The silent ischemia ratio after exercise tended to decrease, although not significantly so (p = 0.2), in patients who received oral nitrates; there was no difference in the response to spray or tablet in this regard. We conclude that ST-segment depression frequently persists after relief of exercise-induced angina pectoris and more so in elderly patients.
Flugelman
M Y
MY
Department of Cardiology, Lady Davis Carmel Hospital, Haifa, Israel.
Halon
D A
DA
Shefer
A
A
Schneeweiss
A
A
Peer
M
M
Dagan
T
T
Lewis
B S
BS
D000286:Administration, Sublingual; D000328:Adult; D000336:Aerosols; D000367:Age Factors; D000368:Aged; D000787:Angina Pectoris / Q000188:drug therapy / Q000503:physiopathology*; D002986:Clinical Trials as Topic; D003327:Coronary Disease / Q000188:drug therapy / Q000503:physiopathology*; D004562:Electrocardiography; D005080:Exercise Test; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects / Q000503:physiopathology; D006801:Humans; D007548:Isosorbide Dinitrate / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D011897:Random Allocation
D000336:Aerosols; D007548:Isosorbide Dinitrate