This study has been performed on a total of 427 cases whose courses and prognosis were followed for one to six years, up in order to determine the most useful electrocardiographic criteria of the single two-step exercise test.
The subjects were classified into the following five groups.
Group 1: coronary-sclerotic patients (typical angina pectoris etc.) ; 41 cases,
Group 2: patients with possible or undeniable coronary sclerosis; 120 cases,
Group 3; patients not associated with cardiovascular diseases; 95 cases,
Group 4: patients with NCA; 90 cases, and Group 5: normal healthy persons; 81 cases.
The cases with definite ST·T change, bundle branch block and auricular fibrillation in resting electrocardiograms were not included for this study.
The author would like to propose the new criteria which is better than the previous criteria.
Considering Q-Q line as reference base line, the following change in ECG in any lead except Lead III and/or V
2 was interpreted as abnormal response.
(1) Any depression of ST or J of 1.5mm or more.
(2) Ischemic ST depression of 0.5mm or more.
(3) Junctional ST depression of 0.5mm or more, measuring at the point 0.04 sec. apart from J and accompanied by QX/QT ratio of 50 per cent or more and/or QT ratio 1.08 or more.
(4) Inverted or isoelectric T waves.
Utilizing above criteria, 53.1 per cent of abnormal response has been found in ST depression in the first or coronary-sclerotic group, that is, almost the same with the Master's classic criteria, while about 10 per cent in the third and fourth group, decreasing the number of false-positive incidence.
View full abstract