Dataset of manually measured QT intervals in the electrocardiogram

Dataset of manually measured QT intervals in the electrocardiogram

BACKGROUND The QT interval and the QT dispersion are currently a subject of considerable interest. Cardiac repolarization delay is known to favor the development of arrhythmias. The QT dispersion, defined as the difference between the longest and the shortest QT intervals or as the standard deviation of the QT duration in the 12-lead ECG is assumed to be reliable predictor of cardiovascular mor...

Electrocardiogram voltage attenuation and shortening of the duration of P-waves, QRS complexes, and QT intervals.

Multiple pathologies in concert may lead to attenuation of the electrocardiogram (ECG) voltage. A case of a patient illustrating the above is presented, who showed marked attenuation of the ECG voltage. Automated values of the amplitude of the ECG QRS complexes, P-waves, and T-waves (in mm), duration of the QRS complexes, P-waves, and QT intervals (in ms), in 2 ECGs were compared. The patient w...

The Electrocardiogram – Waves and Intervals

An analysis of the electrocardiogram QT interval.

No reports testing the efficacy of the use of the QT/RR ratio <1/2 for detecting a normal QTc interval were found in the literature. The objective of the present study was to determine if a QT/RR ratio < or =1/2 can be considered to be equal to the normal QTc and to compare the QT and QTc measured and calculated clinically and by a computerized electrocardiograph. Ratios (140 QT/RR) of 28 succe...

Significance of the QX-QT ratio and the QT ratio (QTr) in the exercise electrocardiogram.

mHE exercise electrocardiogram is a fairly well established and frequently used procedure as an adjunct in the diagnosis of symptomatic or latent coronary insufficiency. Many authors have confirmed its value.'-" The criteria for a positive test, however, still remain somewhat controversial. The value of "ischemic" type ST-segment depression is well documented, but the problem of the significanc...