Enhanced external counterpulsation (EECP) is an effective noninvasive treatment for
patients with coronary artery disease (CAD). EECP has been demonstrated to improve
anginal class and time to ST-segment depression during exercise stress testing. This
study assesses the efficacy of EECP in improving stress-induced myocardial ischemia
using radionuclide perfusion treadmill stress tests (RPSTs). The international study
group enrolled patients from 7 centers with chronic stable angina pectoris and a baseline
ischemic pre-EECP RPST. Patients' demographic and clinical characteristics were recorded.
A baseline pre-EECP maximal RPST was performed within 1 month before EECP treatment.
The results were compared with a follow-up RPST performed within 6 months of completion
of a 35-hour course of EECP. Four centers performed post-EECP RPST to the same level
of exercise as pre-EECP, whereas 3 centers performed maximal RPST post-EECP. The study
enrolled 175 patients (155 men and 20 women). Improvement in angina, defined by >
or =1 Canadian Cardiovascular Society angina class change, was reported in 85% of
patients. In the centers performing the same level of exercise, 81 of 97 patients
(83%) had significant improvement in RPST perfusion images. Patients who underwent
maximal RPST revealed improvement in exercise duration (6.61 +/- 1.88 pre-EECP vs
7.41 +/- 2.03 minutes post-EECP, p <0.0001); 42 of the 78 patients (54%) in this group
showed significant improvement in RPST perfusion images. Thus, EECP was effective
in improving stress myocardial perfusion in patients with chronic stable angina at
both comparable (baseline) and at maximal exercise levels.