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[Clinical significance of prominent negative T waves induced by exercise test]
T Chikamori1, Y Doi, Y Yonezawa
1Department of Medicine & Geriatrics, Kochi Medical School.
Insights
Deep T wave inversion during exercise, a prominent negative T wave (PNT), indicates severe coronary artery disease. This finding suggests a higher likelihood of significant blockages and the need for revascularization in affected patients.
Area of Science:
- Cardiology
- Exercise Physiology
- Diagnostic Imaging
Background:
- The diagnostic significance of deep T wave inversion during exercise stress testing in coronary artery disease (CAD) remains under-investigated.
- Standard exercise tests primarily focus on ST segment depression for CAD detection.
Observation:
- This study evaluated 361 patients with suspected CAD using treadmill exercise tests and coronary arteriography.
- A subset of 16 patients (4%) exhibited prominent negative T waves (PNT) exceeding 8 mm depth, peaking 3-5 minutes post-exercise.
Findings:
- Patients with PNT showed significantly shorter exercise duration (3.3 min) compared to those with ST depressions (4.4 min).
- PNT was strongly associated with severe CAD, with 88% of PNT patients having three-vessel or left main trunk disease, often with >90% stenosis.
- Coronary revascularization rates were higher in the PNT group (69%) versus the ST depression group (36%).
Implications:
- Deep T wave inversion during exercise is a critical indicator of severe, multi-vessel coronary artery disease.
- This finding may refine risk stratification and guide timely intervention strategies in patients undergoing exercise stress tests.
- Further research could explore PNT as a specific marker for high-risk CAD requiring prompt revascularization.
Abstract:
The significance of deep T wave inversion during and after exercise in patients with coronary artery disease has not been studied well. Using the treadmill exercise test (modified Bruce's protocol) and coronary arteriography, we evaluated 361 patients suspected of having coronary artery disease. Results were compared for patients who developed significant T wave inversions of greater than 8 mm (prominent negative T wave: PNT) and for patients who had significant down-sloping ST depressions (DS). Sixteen patients had PNT (4%) which became maximum three to five min after exercise, and ranged in depth from 8 to 15 mm (10.9 +/- 2.4 mm). There were 83 patients with DS (23%). Exercise duration was 3.3 +/- 1.4 min in the PNT group and 4.4 +/- 1.9 min in the DS group (p less than 0.01). Prevalence of three-vessel disease or left main trunk disease was 88% (14 patients) in the PNT group, 28% in the DS group, and 19% (70 patients) in the entire 361 patients. Among the 14 patients who had three-vessel disease or left main trunk disease in the PNT group, the degree of multiple stenoses exceeded 90% in the major coronary arteries and that of the left main trunk stenosis exceeded 75%. The two remaining patients included one with two-vessel disease and severe 99% narrowing of the major coronary arteries and one patient having one-vessel disease with vasospastic angina during exercise. Prevalence of coronary revascularization was 69% in the PNT group and 36% in the DS group (p less than 0.025).(ABSTRACT TRUNCATED AT 250 WORDS)