| Title |
QT dispersion as an attribute of T-loop morphology |
| Published in |
Circulation (Baltimore), Vol. 99, No. 11, p.1458-1463. ISSN 0009-7322. |
| Author |
Kors, J.A. (Jan); Herpen, van G. (Gerard); Bemmel, van J.H. (Jan) |
| Date |
1999-01-01 |
| Language |
English |
| Type |
article |
| Abstract |
BACKGROUND: The suggestion that increased QT dispersion (QTD) is due to
increased differences in local action potential durations within the
myocardium is wanting. An alternative explanation was sought by relating
QTD to vectorcardiographic T-loop morphology. METHODS AND RESULTS: The T
loop is characterized by its amplitude and width (defined as the spatial
angle between the mean vectors of the first and second halves of the
loop). We reasoned that small, wide ("pathological") T loops produce
larger QTD than large, narrow ("normal") loops. To quantify the
relationship between QTD and T-loop morphology, we used a program for
automated analysis of ECGs and a database of 1220 standard simultaneous
12-lead ECGs. For each ECG, QT durations, QTD, and T-loop parameters were
computed. T-loop amplitude and width were dichotomized, with 250 microV
(small versus large amplitudes) and 30 degrees (narrow versus wide loops)
taken as thresholds. Over all 1220 ECGs, QTDs were smallest for large,
narrow T loops (54.2+/-27.1 ms) and largest for small, wide loops (69.
5+/-33.5 ms; P<0.001). CONCLUSIONS: QTD is an attribute of T-loop
morphology, as expressed by T-loop amplitude and width. |
| Publication |
http://hdl.handle.net/1765/9062 |
| Persistent Identifier |
urn:NBN:nl:ui:15-1765/9062 |
| Metadata |
XML |
| Repository |
Erasmus University Rotterdam |