Interval

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Related to QRS interval: QT interval

INTERVAL. A space of time between two periods. When a person is unable to perform an act at any two given periods, but in the interval he has performed such act, as when a man is found to be insane in the months of January and March, and he enters into a contract or makes a will in the interval, in February, he will be presumed to have been insane at that time; and the onus will lie to show his sanity, on the person who affirms such act. See Lucid interval.

A Law Dictionary, Adapted to the Constitution and Laws of the United States. By John Bouvier. Published 1856.
References in periodicals archive ?
Comparison of PR, QRS, QTc, TP Interval between smokers and Non-Smokers Measurements Smokers (N-150) Non-smokers (N-150) P value Mean +/- SD Mean +/- SD * PR interval (sec) 0.1429 +/- 0.003 0.1550 +/- 0.001 <0.001 QRS interval (sec) 0.089 +/- 0.094 0.0783 +/- 0.0014 0.163 QTc interval (sec) 0.38 +/- 0.016 0.37 +/- 0.016 0.007 TP interval(sec) 0.25 +/- 0.0149 0.29 +/- 0.0141 <0.001 * Student's 't' test.
Sodium channel blockers including class I antiarrhythmics by blocking inward sodium current can slow depolarization, reduce conduction velocity, and prolong the QRS interval and consequently may increase the risk of arrhythmia [13,16].
(a) PR QRS prolongation prolongation Variable OR (95% CI) PTrend OR (95% CI) PTrend Well-water arsenic ([mu]g/L) (b) Model 1 (c) 0.94 (0.68, 0.67 1.15 (0.94, 0.17 1.28) 1.41) Model 2 (d) 0.88 (0.63, 0.44 1.12 (0.90, 0.31 1.22) 1.39) Model 3 (e) 0.96 (0.68, 0.83 1.09 (0.86, 0.48 1.36) 1.37) Urinary arsenic ([mu]g/g creatinine) (b) Model 1 (c) 0.72 (0.45, 0.16 1.06 (0.87, 0.56 1.14) 1.29) Model 2 (d) 0.69 (0.42, 0.12 1.11 (0.91, 0.29 1.11) 1.35) Model 3 (e) 0.80 (0.47, 0.41 1.09 (0.76, 0.63 1.37) 1.57) (a) A PR interval of > 200 msec was considered PR prolongation; a QRS interval of [greater than or equal to] 120 msec was considered QRS prolongation.
A prolonged QRS interval suggests a diseased ventricular conduction system and has been associated with increased risk for sudden cardiac death, among other heart disorders.
Because QT interval includes QRS duration, with the latter mostly representing the ventricular depolarization process, we analyzed QRS interval in models identical to those for the QT variables.
All subjects had New York Heart Association class II or previously symptomatic class I heart failure, a left ventricular ejection fraction of 40% or less, and a wide QRS interval of at least 120 ms.
On average, the VDP was significantly reduced by 132.88 mm x msec; the QRS interval was also reduced by 2.95 msec, both indicating a trend away from LVH.
Because the conduction pathways in a child's heart are the same as those in an adult's, the waveforms (P, QRS, T) are labeled in the same fashion, and the timing of the waveforms is measured in the same way (i.e., PR interval, QRS interval, QT interval).
* Prolonged QRS interval with bizarre QRS morphology.
The CARE-HF trial enrolled patients with New York Heart Association (NYHA) class III or IV heart failure, a left ventricular ejection fraction of 35% or less, a left ventricular end-diastolic dimension of at least 30 mm, and a QRS interval of at least 120 msec.
Among athletes 14% (7/50) subjects showed increased QRS interval period, none had any momentum of decreased QRS intervals.