Head-to-head comparison of peak upright bicycle and post-treadmill echocardiography in detecting coronary artery disease: a randomized, single-blind crossover study.

Background Post-treadmill digital echocardiography (post-TME) is the most widely used form of exercise echocardiography, but ischemia can rapidly resolve in the postexercise period; peak upright bicycle digital echocardiography (UBE) has the advantage of providing images at peak exercise that reflect normal physiology. However, the comparative accuracy of the two methods in detecting ischemia in the same patients is unknown. To compare the relative diagnostic value of peak UBE and post-TME in detecting coronary artery disease, both tests were performed in 86 consecutive patients undergoing coronary angiography. Methods Eighty-six patients referred for evaluation of coronary disease underwent peak UBE (starting at 25 W, with 25-W increments every 3 min) and post-TME (Bruce protocol) in a random sequence. Digitized images of peak UBE and post-TME were interpreted in a random and blinded fashion. Results More transient wall motion abnormalities were detected with peak UBE than post-TME (55 vs 42, P <.001), and such exercise-induced wall motion abnormalities were more extensive (5.5 ± 3.0 vs 3.4 ± 2.1 dyskinetic segments, P <.001) and more severe (regional wall motion score index, 2.7 ± 0.5 vs 2.5 ± 0.5; P =.003). By angiography, 59 patients had coronary artery disease (a coronary stenosis of ≥50% diameter narrowing); the sensitivity of peak UBE for detecting coronary artery disease was greater than that of post-TME in the population as a whole (88% vs 66%, P <.01) and in the single-vessel subgroup (72% vs 44%, P <.05), with no worsening in specificity (89% vs 89%, P = NS). Conclusions Peak UBE is more capable of detecting ischemia than post-TME, and this is achieved with no worsening of specificity. Thus, peak UBE should be preferred in patients able to perform bicycle exercise

Detection, location, and severity assessment of left anterior descending coronary artery stenoses by means of contrast-enhanced transthoracic harmonic echo Doppler

AIMS: Contrast-enhanced second harmonic Doppler (ED) is a new ultrasound modality that increases the feasibility of recording blood flow velocity (BFV) in the left anterior descending coronary artery (LAD) using a transthoracic approach. Blood flow velocity convective acceleration is a reliable marker of coronary stenosis and can be used to assess the percentage area reduction at the stenosis site by applying the continuity equation. To detect, locate, and assess the severity of significant stenosis throughout the LAD by means of an ED recording of BFV acceleration at the stenosis site. METHODS AND RESULTS: Fifty-three consecutive patients undergoing coronary angiography (CA) underwent a colour-guided pulsed-wave ED recording of BFV in the proximal/mid and distal portions of the LAD, and maximal and reference BFV was obtained in each of the two arterial segments. Maximal velocity was much higher in the diseased segments (>or=50% lumen narrowing) than in the normal segments (143 +/- 84 vs. 38 +/- 20 cm/s; P < 0.001); as the reference velocity was similar (37 +/- 13 vs. 31 +/- 12; P = 0.03), the percentage increase in velocity was also higher (290 +/- 233 vs. 20 +/- 37%; P < 0.001). Using a cut-off value of an 82% increase in velocity, sensitivity and specificity vs. CA was, respectively, 86 and 95%. The reduction in the percentage area of stenosis calculated using the continuity equation agreed with that determined by means of quantitative CA (r = 0.7). CONCLUSION: Blood flow velocity evaluation in the LAD by means of transthoracic ED is feasible and reliable in detecting, locating, and assessing the severity of LAD stenosis