A matched pairs comparison of cycle ergometry and treadmill exercise testing in the evaluation of coronary heart...

In 105 patient pairs, matched for sex, aged within a ten-year range and with closely similar coronary disease, the sensitivity and specificity of treadmill testing using the Bruce Protocol was compared to cycle ergometry using the 100 kpm/min (16 W/min) increment protocol, and found to be similar. The parameters of use were ST segment depression (sensitivity of 52% for treadmill and 61% for cycle), test angina (65% and 61%), significant work impairment (66% and 68%) and impaired blood pressure response (31% and 20%). The sensitivity was increased (treadmill to 84%, cycle to 89%) if the four parameters were grouped, and abnormality in any one of them was regarded as a positive test. The equivalent severity of coronary disease resulted in more severe work impairment on the cycle than on the treadmill. The mean work level of the treadmill group was 80%, and of the cycle group, 61% of their respective, nomographically predicted, normal values. The difference was similar for the zero, single and multivessel disease groups. This difference should be recognised when comparing the two techniques.