Supine bicycle versus post-treadmill exercise echocardiography in the detection of myocardial ischemia: A randomized single-blind crossover trial

OBJECTIVES We sought to determine the comparative accuracy of supine bicycle exercise echocardiography (SBE) and posttreadmill exercise echocardiography (TME) in detecting myocardial ischemia in patients with known or suspected coronary artery disease (CAD). BACKGROUND Supine bicycle echocardiography and TME have been used for evaluation of CA D. However, the comparative accuracy of these modalities in the detection o f ischemia in the same patients is not known. METHODS Seventy-four patients (age 59 +/- 9 years [mean +/- SDI) referred for evalu ation of coronary disease underwent SEE (starting at 25 to 50 W with 25-W i ncrement every 3 min) and post-TME (Bruce protocol) in a random sequence Di gitized images at baseline and maximal exercise were interpreted in a rando m and blinded fashion. RESULTS Maximal heart rate was higher during TME, whereas systolic blood pressure w as higher during SEE, resulting in a similar double product AL quantitative angiography (n = 67), 57 patients had coronary stenosis (>50%). During SEE , ischemia was detected in 47 patients compared with 38 patients by TME (p < 0.001). Wall motion score index at maximal exercise was higher with SEE t han with TME (1.48 +/- 0.51 vs. 1.38 +/- 0.43; p < 0.001). The extent of my ocardial ischemia (number of ischemic segments) was higher during SEE compa red with TME (3.3 +/- 3.4 vs. 2.3 +/- 2.9 segments; p = 0.004), whereas sev erity of abnormal wall motion was similar. The sensitivity of SEE and TME f or CAD was 82% and 75% with a specificity of 80% and 90%, respectively. Ima ge quality was similar with both techniques. Patients and sonographers favo red SEE over TME. CONCLUSION During SBE and TME exercise, patients achieve a similar double product. Dur ing SEE, however, the detection of ischemia is more frequent and more exten sive which, along with patient and sonographer preference, makes supine bic ycle exercise a valuable stress echocardiographic modality. (C) 1999 by the American College of Cardiology.