Redbud Medical Systems, Inc.
Custom-made beds for Supine bike stress echo, Post treadmill imaging exercise echo, & Resting echo

Introduction to the Literature

A few years ago Dr. Harvey Hecht called attention to the value of acquiring echocardiographic stress data during peak exercise rather than after exercise on the treadmill. (See references below.)  Acquisition during the period of peak ischemia rather than during the period of resolution provided a study of increased sensitivity. Using our preferred protocol (described elsewhere in the excerpts - see Table of Contents above) we felt confident that the supine bike exercise protocol provided greater accuracy and greater convenience than did the post-treadmill imaging protocol.  These papers are worth seeking out, for their content is just as applicable today as it was then.

In 1999 Badruddin, et al.confirmed our reports in their work and concluded:

Patients achieve a similar rate-pressure product during [supine bike echocardiography] and [treadmill echocardiography]. However, ischemic wall motion abnormalities at the time of imaging are more frequent and more extensive during supine bicycle echocardiography, which may increase the detection of CAD and facilitate interpretation of ischemia. These findings along with patient and sonographer preference make SBE a useable stress echocardiography modality in the evaluation patients with CAD.

Shamim-M. Badruddin, MD, Anwar Ahmad, MD, Judith Mickelson, MD, FACC, John Abukhalil, RT,William L. Winters, MD, NIACC, Sherif F. Nagueh, MD, FACC,, William A. Zoghbi, MD, FACC. Supine Bicycle Versus Post-Treadmill Exercise Echocardiography in the Detection of Myocardial Ischemia:  A Randomized Single-Blind Crossover Trial.  Journal of the American College of Cardiology.  Vol. 33, No. 6, 1999.

Digital Supine Bicycle Stress Echocardiography: A New Technique for Evaluating Coronary Artery Disease 
HARVEY S. HECHT, MD, FACC, LARRY DEBORD, MS, RDCS, RICHARD SHAW, PHD, ROBERT DUNLAP, MD, FACC, COLMAN RYAN, MD, FACC, SIMON H. STERTZER, MD, FACC, RICHARD K. MYLER, MD, FACC Daly City, California 

Objectives. The objective of this study was to determine the accuracy of digital supine bicycle stress echocardiography, a new technique for evaluating coronary artery disease during peak exercise. 
Background, Prior stress echocardiographic techniques have not utilized peak exercise imaging to determine the extent and location of coronary artery disease.

Methods. Two-hundred twenty-two patients were studied: 180 underwent both supine bicycle stress echocardiography and coronary arteriography; 42 had a <5% likelihood of disease. Forty-three patients had normal coronary arteries, 55 had single-vessel, 42 had double-vessel and 40 had triple-vessel coronary artery disease.

Results. Supine bicycle stress echocardiography was 93% sensitive, 86% specific and 92% accurate for identifying patients with coronary artery disease irrespective of prior myocardial infarction or achievement of >85%% maximal predicted heart rate, The "normalcy" rate in the low probability group was 100%. Supine bicycle stress echocardiography was 87% sensitive, 89% specific and 88% accurate for specific vessel identification. The sensitivity was greatest for the left anterior descending compared with the right coronary artery and the left circumflex coronary artery,(95 % vs. 81 % vs. 78 %, p < 0.01) and for vessels in patients with double- and triple-vessel compared with single-vessel disease (90% vs. 89% vs. 78%, p < 0.05). The procedure was significantly more sensitive for detection of vessels with 90% to 100% compared with 50% to70% diameter stenosis (91% vs. 81%, p < 0.05) and was 88% correct in the prediction of multivessel disease. 
Conclusions. Supine bicycle stress echocardiography is a highly accurate tool for evaluating coronary artery disease, identifying both the patient with coronary artery disease and the location and extent of disease. (J Am Coll Cardiol 1993;21,-950-6)

Supine Bicycle Stress Echocardiography: Peak Exercise Imaging is Superior to Postexercise Imaging
Harvey S. Hecht, MD, Larry DeBord, MS, RDCS, Nancy Sotomayor, RDCS, Richard Shaw, PhD Robert Dunlap, MD, and Colman Ryan, MD, Daly City, California

The abilities of peak exercise (PEAK) stress echocardiography versus postexercise (POST) stress echocardiography to detect coronary artery disease were evaluated in 136 consecutive patients undergoing supine bicycle stress echocardiography and coronary arteriography: 42 (31%) had normal coronary vessels, 38 (28%) had single-vessel disease, 34 (25%) had double-vessel disease, and 22 (16%) had triple-vessel disease. The results were as follows: (1) For detection of disease in the group of patients, sensitivity of PEAK versus POST was 94% versus 83% (P < 0.01) and specificity was 88% versus 90%. (2) For detection of disease in specific vessels, sensitivity of PEAK versus POST was 90% versus 72% (p < 0.0001) and specificity was 89% versus 92%. (3) For evaluation of the three major coronary arteries, sensitivity of PEAK versus POST was 96% versus 85% (p < 0.05) for the left anterior descending artery, 90% versus 65% (p < 0.01) for the right coronary artery, and 79% versus 60% (p < 0.05) for the left circumflex coronary artery. There were no differences in specificity. (4) The percent diameter stenosis of vessels normalizing from PEAK to POST versus vessels abnormal at PEAK and POST was 80.6% -.t 16% versus 85.9% t 14%, p = 0.07. There were no differences in exercise parameters between patients with and without resolution from PEAK to POST. (5) PEAK versus POST accuracy for identification of patients with multivessel disease was 93% versus 68% (p < 0.001). We conclude that stress echocardiography performed during peak exercise is superior to postexercise stress echocardiography. (J Am Soc ECHOCARDIOGR 1993;6:265-71.)

Usefulness of Supine Bicycle Stress Echocardiography for Detection of Restenosis After Percutaneous Transluminal Coronary Angioplasty
Harvey S. Hecht, MD, Larry DeBord, MS, Richard Shaw, PhD, Robert Dunlap, MD, Colman Ryan, MD, Simon H. Stertzer, MD, and Richard K. Myler, MD.

The role of supine bicycle stress echocardiography (SBSE) for detecting restenosis after percutaneous transluminal coronary angioplasty (PTCA) was evaluated in 80 patients: 41 (51%) with single and 39 (49%) with multivessel PTCA (total 129 dilated vessels). Total revascularization was performed in 54 (68%) and partial revascularization in 26 (32%) patients. Restenosis was angiographically demonstrated in 60 patients (75%) and in 72 vessels (56%) 6.1 t 2.9 months after PTCA. The results for detecting restenosis were: (1) SBSE versus exercise electrocardiographic sensitivity, 87 versus 55% (p <0.001); (2) specificity, 95 versus 79%; and (3) accuracy, 89 versus 61% (p <0.001). SBSE was 83% sensitive, 95% specific and 88% accurate for restenosis detection in specific vessels with comparable results for single versus multivessel PTCA and total versus partial revascularization. Sensitivity, specificity and accuracy were: 91, 93 and 91% for the left anterior descending coronary artery, 77, 94 and 85% for the right coronary artery; and 76, 96 and 88% for the left circumflex coronary artery. Ninety4our percent of the nondilated diseased vessels were correctly identified. ft is concluded that SBSE is an excellent tool for identifY6 ing restenosis after PTCA.

(Am J Cardiol 1993;71:293-296)

Supine Bicycle Stress Echocardiography Versus Tomographic Thallium-201 Exercise Imaging for the Detection of Coronary Artery Disease
Harvey S. Hecht, MD, Larry DeBord, MS, RDCS, Richard Shaw, PhD, Henry Chin, MD, Robert Dunlap, MD, Colman Ryan, MD, and Richard K. Myler MD, Daly City, California

To compare the accuracy of supine bicycle stress echocardiography (SBSE), a new technique for evaluating coronary disease during peak exercise, with tomographic thallium-201 exercise imaging (SPECT), 71 patients were evaluated by SBSE, SPECT, and coronary arteriography. Twenty patients had normal coronary vessels; 22 had single-vessel, 14 had double-vessel, and 15 had triple-vessel disease. There were no differences in sensitivity (90% vs 92%), specificity (80% vs 65%), and accuracy (87% vs 85%) between SBSE and SPECT for the group of 71 patients. The results were similar in patients with and without prior myocardial infarction and with single-, double-, or triple-vessel disease. There were no differences between SBSE and SPECT for disease detection for the group of 213 individual vessels in sensitivity (88% vs 80%), specificity (87% vs 84%), and accuracy (88% vs 82%), but SBSE was more sensitive for the left anterior descending artery (97% vs 82%, p < 0.005) and for arteries involved in triple-vessel disease (93% vs 69%, p < 0.0 1) and more specific for the right coronary artery (88% vs 66%, p < 0.01). Supine bicycle exercise was associated with significantly lower maximal heart rates than treadmill exercise but with significantly higher systolic and diastolic blood pressures. There were no differences in heart rate X systolic blood pressure. We conclude that SBSE and SPECT are equally reliable for coronary disease detection in patients and for evaluation of disease in specific arteries with the exception of SBSE's higher sensitivity for the left anterior descending artery and arteries involved in triple-vessel disease and higher specificity for the right coronary artery. (J Am Soc ECHOCARDIOGR 1993;6:177-85.)

Truly Silent Ischemia and the Relationship of Chest Pain and ST Segment Changes to the Amount of Ischemic Myocardium: Evaluation by Supine Bicycle Stress Echocardiography
HARVEY S. HECHT, MD, FACC, LARRY DEBORD, MS, RDCS, NANCY SOTOMAYOR, MS, RDCS, RICHARD SHAW, PHD, COLMAN RYAN, MD, FACC   Daly City, California

Objectives. The objectives of this study were 1) to determine the relationship between the amount of exercise-induced ischemic myocardium and the presence or absence of chest pain and ST segment depression, and 2) to define the incidence and characteristics of "truly silent ischemia," that is, ischemia that is not manifested by symptoms or electrocardiographic (ECG) findings.

Background. There are no prior data relating ischemia to chest pain and ST depression. Thallium-201 imaging studies have evaluated perfusion but not ischemia. In contrast, supine bicycle stress echocardiography demonstrates exercise-induced ischemic dysfunction.

Methods. Supine bicycle stress echocardiography and arteriography were performed in 130 patients and the severity and geographic extent of ischemic myocardium were compared in three groups. On exercise, Group I patients had both chest pain and ST segment depression (symptomatic ischemia), Group 11 patients ST depression without chest pain (asymptomatic ischemia) and Group III patients had neither chest pain nor ST depression (truly silent ischemia).

Results. There were no differences among groups in arteriographic characteristics. The incidence of "truly silent ischemial I was 43%. The number of abnormally contracting ischemic segments, average score per segment and sum of scores were virtually identical in Groups I and II and significantly greater than in Group III for the patients (p < 0.01 to < 0.0001), for the vessels as a group (p < 0.01 to < 0.0001) and for the left anterior descending (p < 0.01 to < 0.0001) and right (p < 0.05) coronary arteries. By multivariate analysis, positive findings on the stress ECG was the single most significant variable in relation to the amount of ischemia (p < 0.001); exercise chest pain had no significant relationship.

Conclusions. Exercise-induced ST segment depression is the single most significant variable in relation to the amount of ischemic myocardium; exercise-induced chest pain is not related to the amount of ischemia. Patients with "truly silent ischemia" constitute almost 50% of patients with coronary artery disease and have less ischemia than do patients with ECG indications of ischemia, with or without chest pain.   (J Am Coll Cardiol 1994,23.369-76)

See  References for many more papers related to stress Echo.

Books on Stress Echocardiography

Stress-Echocardiography
Eugenio Picano 3rd edition (1997) Springer Verlag; ISBN: 3540626204