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Updated: May 28, 2025
Pulse Wave Velocity Testing in the Baltimore Longitudinal Study of Aging
Published on: February 7, 2014
Age-dependent influence of T wave amplitude on short period temporal dispersion in healthy subjects
Gianfranco Piccirillo1, Federica Moscucci2, Martina Mezzadri3
1Department of Internal and Clinical Medicine, Anesthesiology and Cardiovascular Sciences, Policlinico Umberto I, "Sapienza" University of Rome, Viale del Policlinico, n.155, 00185 Rome, Italy; Department of Internal Medicine and Medical Specialties, Geriatric Division, Policlinico Umberto I, Viale del Policlinico, n.155, 00185 Rome, Italy.
Background:
T wave amplitude and repolarization variability in ECG showed inverse correlations. Sympathetic activation, induced by head-up tilt, is associated to a reduced T wave amplitude.
Methods:
Noninvasive hemodynamic and ECG data from three healthy subjects' groups (Group 1: 10-19 years-old; Group 2: 40-49 years-old; Group 3: 80-89 years-old) were analyzed. Measurements were taken during controlled-breathing rest, and during head-up tilt. The mean and standard deviation (SD) were calculated for these ECG intervals: QT, STp (from S to Tpeak) and Te (from Tpeak to Tend).
Results:
During tilt, a significant decrease in T wave amplitude was observed in the younger groups (p < 0.001), but not in Group 3. At rest, Group 1 exhibited higher voltage compared to Group 2 (p < 0.05) and 3 (p < 0.001), as Group 2 compared to Group 3 (p < 0.05). A negative correlation was confirmed between T wave amplitude and QTSD, STpSD and TeSD (p < 0.001). Low-frequency normalized units (p < 0.05) and high-frequency normalized units (p < 0.001) were inversely related to T-wave amplitude.
Conclusion:
The findings suggest an age-dependent decline in T wave amplitude during tilt and elucidates the relationship between systolic function and T wave amplitude among healthy subjects. These insights warrant further investigations in clinical and research settings for cardiovascular diseases.
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