FIRST-PASS RADIONUCLIDE ANGIOGRAPHY DURING BICYCLE AND TREADMILL EXERCISE

Background. Treadmill testing is usually preferred over cycle ergometr y because of the greater sensitivity in diagnosing coronary artery dis ease, Treadmill testing has only recently been used with radionuclide angiography (RNA) because patient motion makes RNA imaging difficult, In this study we evaluate the comparability of treadmill and cycle exe rcise RNA with a dual isotope motion correction technique. Methods and Results. Volunteer patients (n = 27) performed first-pass RNA during maximal exercise using both cycle ergometer and treadmill, Exercise ca pacity was greater during treadmill exercise (8.1 +/- 2.4 vs 7.5 +/- 2 .2 METs), Twenty-three of 27 treadmill and all cycle ergometer exercis e studies were technically adequate, Maximal heart rate was greater du ring treadmill exercise (150 +/- 24 vs 143 +/- 25 beats min - 1), ho wever, systolic blood pressure was greater during cycle ergometry (174 +/- 23 vs 188 +/- 25 mmHg), resulting in no difference in heart rate times systolic blood pressure (25.7 +/- 7.2 vs 26.9 +/- 6.0). There we re no differences between treadmill and cycle ergometer for peak exerc ise left ventricular ejection fraction (56% +/- 13% vs 57% +/- 14%) (r = 0.89). Calculated left ventricular end-diastolic volume was not dif ferent at rest (183 +/- 42 ml vs 176 +/- 44 ml) but differed significa ntly at peak exercise (282 +/- 75 ml vs 231 +/- 60 ml). The clinical i mpression, based on wall motion and left ventricular ejection fraction was very similar between treadmill and cycle ergometer. Conclusion. T readmill exercise RNA is feasible, with about 85% of studies likely to be technically adequate, The overall clinical results are very simila r to cycle exercise RNA, although the ordinarily expected advantages o f treadmill exercise were largely absent.