PERFEXT (PERFusion, PERFormance, EXercise Trial)
A Randomized Trial of Exercise Training in Patients With Coronary Heart Disease, Froelicher, Jensen, et al.
NHLBI funded at UCSD (1979-1983)
In order to determine whether or not regular exercise could alter myocardial perfusion or function, we randomized 146 male volunteers with stable coronary heart disease to either a supervised exercise program (n = 72) or to a usual care program (n = 74). The study was performed at the University of California at San Diego and Veterans Affairs Medical Center in San Diego. Subjects underwent exercise tests initially and one year later. Significant differences between the two groups included improved aerobic capacity, thallium ischemia scores, and ventricular function in the exercise intervention group. It was not possible to classify the conditions of patients as to the likelihood of improvement or deterioration. This study demonstrated changes in myocardial perfusion and function in a select group of middle-aged men with coronary heart disease who underwent a medically appropriate exercise program lasting one year, but these changes were relatively modest.
Froelicher VF, Jensen D, Genter F, Sullivan M, McKirnan MD, Witztum K, Scharf J, Strong ML and Ashburn W. A randomized trial of exercise training in patients with coronary heart disease. JAMA 1984;252:1291-1297.
Robinson G, Froelicher VF, and Utley JR. Rehabilitation of the coronary artery bypass graft surgery patient. J Cardiac Rehab 1984;4:74-86.
Myers J, Ahnve S, Froelicher VF, Livingston M, Jensen D, Abramson I, Sullivan M, and Mortara D. A randomized trial of the effects of 1 year of exercise training on computer-measured ST segment displacement in patients with coronary artery disease. J Am Coll Cardiol 1984;4:1094-1102.
Froelicher VF, Jensen D, and Sullivan M. A randomized trial of the effects of exercise training after coronary artery bypass surgery. Archives of Internal Medicine 1985;145:689-692.
Froelicher VF, Sullivan M, Myers J, and Jensen D. Can patients with coronary artery disease receiving beta blockers obtain a training effect? Am J Cardiol 1985;55:155D-161D.
Sullivan M, Ahnve S, Froelicher VF, and Myers J. The influence of exercise training on the ventilatory threshold of patients with coronary heart disease. Am Heart J 1985;109:458-463.
Hammond HK, Kelly TL, Froelicher VF, and Pewen W. Use of clinical data in predicting improvement in exercise capacity after cardiac rehabilitation. J Am Coll Cardiol 1985;6:19-26.
QUEXTA (QUantitative Coronary Angiography and Computerized EXercise Testing)
The Electrocardiographic Exercise Test in a Population with Reduced Workup Bias: Diagnostic Performance, Computerized Interpretation, and Multivariable Prediction, Froelicher, Lehmann, et al.
VAMC Cooperative Studies Program CSP#16 (1988-1996)
Background: Empirical scores, computerized ST-segment measurements, and equations have been proposed as tools for improving the diagnostic performance of the exercise test.
Objective: To compare the diagnostic utility of these scores, measurements, and equations with that of visual ST-segment measurements in patients with reduced workup bias.
Design: Prospective analysis.
Setting: 12 university-affiliated Veterans Affairs Medical Centers.
Patients: 814 consecutive patients who presented with angina pectoris and agreed to undergo both exercise testing and coronary angiography.
Measurements: Digital electrocardiographic recorders and angiographic calipers were used for testing at each site, and test results were sent to core laboratories.
Results: Although 25% of patients had previously had testing, workup bias was reduced, as shown by comparison with a pilot study group. This reduction resulted in a sensitivity of 45% and a specificity of 85% for visual analysis. Computerized measurements and visual analysis had similar diagnostic power. Equations incorporating non-ECG variables and either visual or computerized ST-segment measurement had similar discrimination and were superior to single ST-segment measurements. These equations correctly classified 5 more patients of every 100 tested (areas under the receiver-operating characteristic curve, 0.80 for equations and 0.68 for visual analysis; P < 0.001) in this population with a 50% prevalence of disease.
Conclusions: Standard exercise tests had lower sensitivity but higher specificity in this population with reduced work-up bias than in previous studies. Computerized ST-segment measurements were similar to visual ST-segment measurements made by cardiologists. Considering more than ST-segment measurements can enhance the diagnostic power of the exercise test.
Froelicher VF; Lehmann KG; Thomas R; Goldman S; Morrison D; Edson R; Lavori P; Myers J; Dennis C; Shabetai R; Do D; Froning J. The electrocardiographic exercise test in a population with reduced workup bias: diagnostic performance, computerized interpretation, and multivariable prediction. Veterans Affairs Cooperative Study in Health Services #016 (QUEXTA) Study Group. Quantitative Exercise Testing and Angiography. Ann Intern Med 1998 Jun 15;128(12 Pt 1):965-74