Real-time assessment of myocardial perfusion and wall motion during bicycle and treadmill exercise echocardiography: Comparison with single photon emission computed tomography

OBJECTIVES We sought to determine the feasibility and accuracy of real-time imaging of myocardial contrast echocardiography (MCE) in detecting myocard ial perfusion defects during exercise echocardiography compared with radion uclide tomography. BACKGROUND Ultrasound imaging at a low mechanical index and frame rate (10 to 20 Hz) after intravenous injections of perfluorocarbon containing microb ubbles has the potential to evaluate myocardial perfusion and wall motion ( WM) simultaneously and in real time. METHODS One hundred consecutive patients with intermediate-to-high probabil ity of coronary artery disease underwent treadmill (n = 50) or supine bicyc le (n = 50) exercise echocardiography. Segmental perfusion with MCE and WM were assessed in real time before and at peak exercise using low mechanical index (0.3) and frame rates of 10 to 20 Hz after 0.3 mi bolus injections o f intravenous Optison (Mallinckrodt Inc., San Diego, California). All patie nts had a dual isotope (rest thallium-201, stress sestamibi) study performe d during the same exercise session, and 44 patients had subsequent quantita tive coronary angiography. RESULTS In the 100 patients, agreement between MCE and single photon emissi on computed tomography (SPECT) was 76%, while it was 88% between MCE and WM assessment. Compared with quantitative angiography, sensitivity of MCE, SP ECT and WM was comparable (75%), with a specificity ranging from 81% to 100 %. The combination of MCE and WM had the best balance between sensitivity a nd specificity (86% and 88%, respectively) with the highest accuracy (86%). CONCLUSIONS The real-time assessment of myocardial perfusion during exercis e stress echocardiography can be achieved with imaging at low mechanical in dex and frame rates. The combination of WM and MCE correlates well with SPE CT and is a promising important addition to conventional stress echocardiog raphy. (J Am Coil Cardiol 2001;37:741-7) (C) 2001 by the American College o f Cardiology.