V-A interval

interval /in·ter·val/ (in´ter-val) the space between two objects or parts; the lapse of time between two events.

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atrioventricular (AV) interval  the time between the start of atrial systole and the start of ventricular systole, equivalent to the P–R interval of electrocardiography.

cardioarterial interval  the time between the apex beat and arterial pulsation.

confidence interval  an estimated statistical interval for a parameter, giving a range of values that may contain the parameter and the degree of confidence that it is in fact there.

coupling interval  the length of time between an ectopic beat and the sinus beat preceding it; in an arrhythmia characterized by such beats, the intervals may be constant (fixed coupling i's) or inconstant (variable coupling i's) .

escape interval  the interval between an escape beat and the normal beat preceding it.

interdischarge interval  the time between two discharges of the action potential of a single muscle fiber.

interpotential interval  the time between discharges of action potentials of two different fibers from the same motor unit.

P–R interval  the portion of the electrocardiogram between the onset of the P wave (atrial depolarization) and the QRS complex (ventricular depolarization).

lucid interval 

1. a brief period of remission of symptoms in a psychosis.

2. a brief return to consciousness after loss of consciousness in head injury.

pacemaker escape interval  the period between the last sensed spontaneous cardiac activity and the first beat stimulated by the artificial pacemaker.

P–P interval  the time from the beginning of one P wave to that of the next P wave, representing the length of the cardiac cycle.

QRS interval  the interval from the beginning of the Q wave to the termination of the S wave, representing the time for ventricular depolarization.

QRST interval , Q–T interval the time from the beginning of the Q wave to the end of the T wave, representing the duration of ventricular electrical activity.

systolic time intervals  (STI) any of several intervals measured for assessing left ventricular performance, particularly left ventricular ejection time, electromechanical systole, and preejection period.

V–A interval  the time between a ventricular stimulus and the atrial stimulus following it.

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V-A interval

Physiologic retrograde conduction time Cardiac pacing DVI, DDD The period of time elapsing in a dual-chamber pacemaker from a ventricular event–sensed or paced–to the next scheduled atrial pace. See Pacemaker.