PR segment

PR seg·'ment

that part of the electrocardiographic curve between the end of the P wave and the beginning of the QRS complex.
Farlex Partner Medical Dictionary © Farlex 2012

PR seg·ment

That part of the electrocardiographic curve between the end of the P wave and the beginning of the QRS complex.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
The exercise-induced tachycardia increases the magnitude of the P and [T.sub.a] waves and shortens the PR segment, thus shifting the atrial repolarization wave into the ST segment.
To avoid errors, it should be measured in relation to the end of the PR segment, not the TP segment [10].
A 12-lead electrocardiography revealed sinus rhythm with the left axis deviation of the P-wave and normal PR interval without PR segment. A Holter monitor revealed sinus arrest, atrioventricular junctional escape, and paroxysmal AF with a 4.3 s RR interval.
PR segment depression and isoelectric small PR segment were observed (Harrison and Harrison, 1986; Nap et al.,1992) in 75 and 25% cases respectively and seem related to fast heart rate and early atrial depolarization even before completion of ventricular repolarization in birds (Harrison and Harrison, 1986).'Q' wave was not observed in most of the pigeons in lead II.'R' wave was very small (r) but 'S' (negative deflection) was quite appreciable.
Carefully monitor your website traffic around the time of a major PR segment or placement; ideally, there should be an identifiable growth related to your efforts.
Reduced ventricular conduction velocity and prolonged PR segment appeared first, at just 0.1 [micro]M BPA--well below reported human urinary concentrations of 0.024 to 8.5 [micro]M BPA.
Her EKG showed ST-segment elevation in anterior and inferior leads, with no PR segment depression (Figure1).
We confirmed AV conduction delays by measuring the PR segment time in the ECG, which lengthened after 15 min of exposure to BPA at all concentrations.
AV conduction delay was confirmed by measuring PR segment time, with delays found at BPA doses as low as 0.1 [micro]M BPA.
Atrial repolarization was not present as Ta wave in the PR segment. The presence of Ta in the ECG of birds is normal, but, in some animals, such as dogs, it is considered as evidence of right atrial hypertrophy.
* Ultimately the ST and PR segments normalise, which may be followed by widespread T-wave inversion.