In the current study, the most frequent ECG change observed was P-pulmonale (68%) and the next common change was Right Axis Deviation of QRS Complex
(beyond +90 degrees).
The QRS complexes
marked by yellow arrows were confirmed to be artefacts because they appeared in too rapid succession following or preceding a normal sinus complex, which would be physiologically impossible with a normal AV conduction (Figure 1).
This way, the ECG can be described at different scales of temporal and frequency resolution, and thus high frequency waves (such as the QRS complex
) can be distinguished from low frequency waves (such as P- and T-waves).
Folsom, "Prognostic significance of corrected QT and corrected JT interval for incident coronary heart disease in a general population sample stratified by presence or absence of wide QRS complex
: the ARIC study with 13 years of follow-up," Circulation, vol.
Thus, the greater the distance from the ventricle, the greater the attenuation of the QRS complex
. Nonetheless, the current signal conditioning and acquisition systems provide good quality signals for a wide range of input signal amplitudes such as those used in this study.
The mean QRS complex
time was measured as 70[+ or -]15 ms before treatment (min-max: 40-120 ms) and 63[+ or -]16 ms after treatment (min-max: 40-120 ms).
Brugada-type ECG pattern and extreme QRS complex
widening with propafenone overdose.
The QT interval was measured manually in the 12 ECG leads and was rated with time interval between the initial deflection of the QRS complex
and the point at which a tangent drawn to the steepest portion of the terminal part of the T wave crossed the isoelectric line.
end of QRS complex
to the onset of the T-wave) in the right * Filtered QRS duration (fQRS) precordial leads ([V.sub.1] to [greater than or equal to] 114 [V.sub.3]).
However these supraventricular tachycardia with narrow or wide QRS complex
are rarely life threatening.
The short PR interval (0.10 seconds), wide QRS complex
(0.12 seconds), and delta waves (best seen in leads II, III, aVF, V1, V3-V6), are features of ventricular preexcitation of the Wolff-ParkinsonWhite type (WPW).
The some of the limitations of ECG is an inaccuracy in input feature vectors of the classifier caused by substantial overlapping of the frequencies of the P-wave, T-wave, QRS complex
and the noise.