Related Experiment Videos
Anginal threshold between stress tests: exercise versus dobutamine stress echocardiography
Marie Arsenault1, Sébastien Bergeron, Jean-G Dumesnil
1Quebec Heart and Lung Institute/Laval Hospital, Ste-Foy, Quebec, Canada G1 V 4G5.
Medicine and Science in Sports and Exercise
|January 6, 2005
Summary
Dobutamine echocardiography (DOB) can estimate anginal threshold, but it occurs at a slightly higher heart rate and workload than exercise testing (EX). Target heart rate goals from exercise may not directly apply to DOB stress tests.
Area of Science:
- Cardiology
- Diagnostic Imaging
- Clinical Physiology
Background:
- Dobutamine echocardiography (DOB) is an alternative to exercise testing (EX) for cardiac evaluation.
- The clinical significance of achieving 85% of maximal predicted heart rate (%PHR) during DOB, similar to EX, requires further investigation.
Purpose of the Study:
- To compare the ischemic threshold between exercise testing (EX) and dobutamine echocardiography (DOB).
- To evaluate the validity of using %PHR as a target for DOB stress tests.
Main Methods:
- Twenty men with stable angina underwent randomized DOB and EX echocardiograms.
- Measurements included electrocardiography, heart rate (HR), and systolic blood pressure.
- Ischemic threshold was defined as the onset of clinical angina.
Main Results:
- The anginal threshold occurred at higher rate-pressure product (RPP), HR, and %PHR during DOB compared to EX.
- Specifically, RPP was higher (P=0.02), HR was higher (P=0.01), and %PHR was higher (P<0.01) during DOB.
- 32% of subjects had an ischemic HR >85% PHR, and 60% had a higher ischemic HR during DOB versus EX.
Conclusions:
- Estimating the anginal threshold during DOB is feasible and approximately 10% higher than during EX.
- Extrapolating target heart rates from EX to DOB may not be clinically valid.