Heart rate adjustment of ST segment depression for improved detection of coronary artery disease.
Why the study?
Do heart rate-adjusted indexes of ST segment depression improve the detection of coronary artery disease compared to standard exercise electrocardiographic criteria?
Population
300 subjects, comprising 150 with a low likelihood of coronary artery disease for derivation, and 150…
Comparison
Heart rate-adjusted indexes of ST segment… vs Standard exercise electrocardiographic criteria
Design
Cross-sectional
Authors
Discussion
Loading...
Member takes
Implication
Heart rate-adjusted ST indexes may improve CAD detection on exercise ECG; leaves open need for prospective validation before practice change.
Key Points
- To assess whether adjusting ST segment depression relative to heart rate during treadmill exercise electrocardiography enhances the diagnostic detection of coronary artery disease.
- Derived normal reference cutoff values using 95th-percentile estimation in 150 subjects with a low likelihood of coronary disease (100 healthy individuals and 50 with nonanginal chest pain).
- Evaluated diagnostic sensitivity in 150 patients with a high likelihood of coronary disease, including 100 patients with angiographically confirmed stenosis and 50 with stable angina.
- Standard treadmill exercise electrocardiographic criteria identified coronary disease with a sensitivity of 68% (102 of 150 subjects).
- An ST segment/heart rate slope cutoff of 2.4 muV/beats/min achieved 95% sensitivity (142 of 150 subjects, p < 0.001), while a delta ST segment/heart rate index cutoff of 1.6 muV/beats/min achieved 91% sensitivity (137 of 150 subjects, p < 0.001).
- Receiver-operating curve analyses demonstrated the superior diagnostic performance of both heart rate-adjusted indexes over standard criteria across a wide range of test specificities.
Structured PICO
Do heart rate-adjusted indexes of ST segment depression improve the detection of coronary artery disease compared to standard exercise electrocardiographic criteria?
P
Population
300 subjects, comprising 150 with a low likelihood of coronary artery disease (100 normal subjects, 50 with nonanginal chest pain) for derivation, and 150 patients with a high likelihood of coronary disease (100 with angiographically demonstrated coronary obstruction, 50 with stable angina) for testing.
I
Intervention
Heart rate-adjusted indexes of ST segment depression (ST segment/heart rate slope and delta ST segment/heart rate index) during treadmill exercise electrocardiography
C
Comparator
Standard exercise electrocardiographic criteria
O
Outcome
Sensitivity for the detection of myocardial ischemia/coronary artery diseasesurrogate
Heart rate adjustment of ST segment depression significantly improves the sensitivity of treadmill exercise electrocardiograms for detecting coronary artery disease compared to standard criteria.
Cite This Study
Kligfield et al. (1989) studied this question.