5] The spectrum of manifestation is still expanding and the followings are recently reported: fetal prolonged PR interval
, first-and second-degree AVB, EFE, prolongation of corrected QT interval, sinus bradycardia (SB), late-onset DCM, atrial flutter, valvular insufficiency, ventricular/valvular hyperechogenicity, pericardial effusion, and other heart disorders even in the absence of cardiac block.
The following parameters were, namely, PR interval
, QRS complex, ST segment were evaluated in seconds.
was measured from the beginning of the P-wave to the beginning of the R-wave and considered the mean of five consecutive beats taken from the lead II.
Table 2 demonstrated the mean values and standard deviations of the electrocardiographic variables: duration of Pms wave, amplitude of Pmv, PR interval
, QRS complex, Rmv wave amplitude, and QT interval.
For example, the detection of a short PR interval
(the time between P and R peaks) is essential to properly diagnosing Wolff-Parkinson-White (WPW) syndrome.
The PR interval
was measured as the distance from the start of the P wave to the start of the QRS complex (normal range of PR interval
: 120-200 ms).
Patient's rhythm was reverted to sinus rhythm and repeat ECG showed short PR interval
and delta wave in V1, V2, V3, V4.
11] The ECGs were analyzed for heart rate, PR interval
, QRS duration, QT interval, QTc interval, and QRS axis.
In the final Jones criteria, a PR interval
longer for age was proposed as a minor criterion, but a PR interval
longer for age and heart rate should be used as a minor criterion, because accompanying fever and myocarditis may lead to tachycardia in these patients.
A short PR interval
, delta wave and wide QRS complex are evidence of pre-excitation (Wolff-Parkinson-White syndrome) and suggest a diagnosis of AVRT or pre-excited AF.
The PR interval
varied, and there was no association of the P waves and QRS complexes in the electrocardiogram.
Treatment with nVNS had no meaningful effect on heart rate, PR interval
, corrected QT interval, or QRS duration.