Key result
Exercise resulted in significantly more symmetrical T waves at 50 seconds postexercise compared to resting reference values (SRarea 1.04 vs 1.68; P < 0.0001).
Why the study?
Does exercise alter T wave shape symmetry in healthy human subjects?
Observational (n=20)
Does exercise alter T wave shape symmetry in healthy human subjects?
p-value: p=<0.0001
T wave shape becomes significantly more symmetrical at higher heart rates following exercise, providing quantitative data on repolarization dynamics.
Does not support changing postexercise ECG interpretation; leaves open whether symmetry metrics aid diagnosis in disease.
T wave shape is increasingly used to provide insights into cardiac repolarization and, although shape is known to change as heart rate changes, there are no published quantitative clinical data. The aim of this study was to quantify these changes. Heart rate (HR), T wave amplitude, and two measures of T wave symmetry (SRarea--ratio of areas about the peak, SRtime--ratio of centrality of peak), were quantified over a period of 360 seconds following exercise in 20 healthy human subjects. As HR decreased, in all subjects the T wave became more asymmetrical (SRarea 20/20, SRtime 20/20, P < 0.0001). Resting reference HR and symmetry ratios were (mean +/- SD), HR 63 +/- 10 beat/min, SRarea 1.68 +/- 0.25, and SRtime 2.13 +/- 0.39. Fifty seconds postexercise, HR was significantly higher than reference at 92 +/- 11 beat/min (P < 0.0001), and symmetry ratios were significantly less at SRarea 1.04 +/- 0.15, SRtime 1.24 +/- 0.36 (P < 0.0001). Significant differences in HR and both symmetry ratios remained at 300 seconds postexercise. Amplitude increases had returned to their reference values at 300 seconds. T wave shape was significantly more symmetrical at higher HRs. These findings confirm qualitative reports of shape changes.
No takes yet. Share an insight, caveat, or question.
Langley et al. (2002) conducted an observational in Healthy (n=20). Exercise vs. Resting reference was evaluated on T wave symmetry (SRarea and SRtime) (p=<0.0001). Exercise resulted in significantly more symmetrical T waves at 50 seconds postexercise compared to resting reference values (SRarea 1.04 vs 1.68; P < 0.0001).
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: