ST/HR slope and improved exercise ECG detection of myocardial ischemia in patients with suspected coronary artery disease.
Predictive values of ST/HR slope and ST-segment displacement during symptom-limited exercise were determined in 85 patients who underwent coronary angiography for suspected coronary artery disease, using perfusional and functional radionuclide images with 99mTc-2-methoxy-isobutil-isonitrile as an index of stress-induced myocardial ischemia. ST/HR slope showed a better sensitivity than conventional stress-induced changes of ST-segment displacement (96% vs. 73%, respectively). In patients with clinical suspicion of coronary artery disease, the main result was the negative predictive value of ST/HR slope when compared with conventional ST-segment displacement (98% vs. 41%). ST/HR slope was unable to perfectly separate patients with different degrees of ischemia, however, subjects without scintigraphic signs of stress-induced ischemia and patients with ischemic impairment in three myocardial regions were correctly identified as distinct populations. In patients with a previous myocardial infarction, no difference was found between the two criteria and a wide overlap of ST/HR slope values was present. The authors conclude that ST/HR slope is useful to detect the rate of change in electric parameters during exercise and might therefore more adequately be used to separate normal from definitely abnormal responses to exercise.
Schiariti
M
M
Second Department of Cardiology, University La Sapienza, School of Medicine, Rome, Italy.
Ciavolella
M
M
Puddu
P E
PE
Giannitti
C
C
Scali
D
D
Schad
N
N
Reale
A
A
D000328:Adult; D000368:Aged; D003287:Contrast Media; D017023:Coronary Angiography; D003327:Coronary Disease / Q000150:complications / Q000175:diagnosis*; D003331:Coronary Vessels; D004562:Electrocardiography; D005080:Exercise Test; D006801:Humans; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications; D009570:Nitriles; D015609:Organotechnetium Compounds; D011237:Predictive Value of Tests; D011875:Radionuclide Angiography; D012680:Sensitivity and Specificity; D017256:Technetium Tc 99m Sestamibi
D003287:Contrast Media; D009570:Nitriles; D015609:Organotechnetium Compounds; D017256:Technetium Tc 99m Sestamibi