sinus arrhythmia

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Related to sinus arrhythmia: Sinus tachycardia


variation from the normal rhythm, especially of the heartbeat; see also dysrhythmia. adj., adj arrhyth´mic.
sinus arrhythmia the physiologic cyclic variation in heart rate, originating in the sinoatrial node and related to vagal impulses to the node; it occurs commonly in children (juvenile arrhythmia) and in the aged.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

si·nus ar·rhyth·mi·a

rhythmic, repetitive irregularity of the heartbeat, the heart being under the control of its normal pacemaker, the sinuatrial node.
Synonym(s): juvenile arrhythmia
Farlex Partner Medical Dictionary © Farlex 2012

si·nus ar·rhyth·mi·a

(sī'nŭs ă-ridh'mē-ă)
A cyclic variation in heart rate, usually normal and linked to respiratory movements.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
Taha BH, Simon PM, Dempsey JA, Skatrud JB, Iber C (1995) Respiratory sinus arrhythmia in humans: an obligatory role for vagal feedback from the lungs.
Condition Number of subjects PSS mean score PSS variance Not stressed 13 22.3 5.6 Stressed 7 27.6 4.7 TABLE 4: Results of the sinus rhythm classification and the sinus arrhythmia detection algorithm.
1985 Changes in heart period, heart period variability and a spectral analysis estimate of respiratory sinus arrhythmia in response to pharmacological manipulations of the baroreceptor reflex in cats.
Patients with COPD have elevated resting heart rate, reduced baroreflex sensitivity, reduced respiratory sinus arrhythmia, a direct increase in muscle sympathetic nerve activity and abnormal heart rate recovery (HRR) following exercise.
Respiratory sinus arrhythmia in humans: how breathing pattern modulates heart rate.
The arrhythmias were grouped into three categories as sinus arrhythmia, abnormalities of impulse formation and abnormalities of impulse conduction (Tilley, 1985).
The group of sinus arrhythmia included Sinus Bradycardia, Sinus Tachycardia, Sinus Arrhythmias and Wandering pacemaker and their prevalence was 3.12 (19/608), 27.13 (165/608), 11.34(69/608), 0.98% (6/608) amongst arrhythmic dogs (Table 1).
DIAGNOSIS: Sinus rhythm with monomorphic ventricular bigeminy and ventriculophasic sinus arrhythmia. Otherwise, the ECG is normal.
This ventriculophasic sinus arrhythmia often is most clearly seen in electrocardiograms showing sinus rhythm with 2:1 atrioventricular block but may be seen in any situation in which some sinus P-P intervals contain QRS complexes, while others do not.
The researchers were interested in seeing if there were physical differences in the way high-power people and low-power people responded to others' suffering; specifically they wanted to test if high-powered individuals would exhibit greater autonomic emotion regulation [or respiratory sinus arrhythmia (RSA) reactivity].
This rhythmic shortening and lengthening of the P-R intervals is usually due to slight sinus arrhythmia while the junctional rhythm is more regular.
The cardiac effects of olanzapine are minimal;[4,5] dose-related sinus arrhythmias and ST-T changes can occur, but these changes are reversible and there is no evidence of more serious EEG changes, such as prolongation of the QT interval.