Disease relevance of Arrhythmia, Sinus

• Sleep was characterized by marked sinus arrhythmia in 14, extreme sinus bradycardia ( less than 30 beats/minute) in six, asystole of 2.5 to 6.3 seconds in five, second degree atrioventricular (A-V) block in two, and ventricular arrhythmias--complex premature ventricular beats in 10 and ventricular tachycardia in two [1].
• Tolazoline, a nonselective alpha-adrenoreceptor antagonist, given iv at 5 mg/kg, reduced the bradycardia and sinus arrhythmia caused by amitraz administration but did not change amitraz-induced hypertension [2].
• A pronounced sinus arrhythmia and/or 2nd-degree atrioventricular block developed in all dogs during xylazine injection after saline infusion [3].
• In conclusion, induction of a low central CRF content by prednisolone leads to a marked hyperreflexia in respiratory sinus arrhythmia and hyporeflexia in the latency time test [4].
• The degree of MVP correlated significantly with the occurrence of arrhythmias, particularly severe sinus arrhythmia [5].

High impact information on Arrhythmia, Sinus

• Diminishment of respiratory sinus arrhythmia foreshadows doxorubicin-induced cardiomyopathy [6].
• Dose/response studies in humans and rhesus monkeys are cited as an example for interspecies comparisons using ED50 calculations for a 30% decrease in the respiratory sinus arrhythmias following atropine [7].
• Respiratory sinus arrhythmias are quantified following atropine sulfate administration and the resulting vagolytic blockade is used as a pharmacologic challenge technique [7].
• The extent of sinus arrhythmia suppression was inversely correlated with the degree of M1 selectivity of the drugs used, advocating the use of M1-selective antiparkinsonian anticholinergics like biperiden in the treatment of extrapyramidal side effects [8].
• Melatonin decreased heart rate by 3.66+/-1.68 beats/min (P<0.05) and pre-ejection period (measure of cardiac sympathetic activity) by 16.48+/-4.28 ms (P<0.05), but had no effect on respiratory sinus arrhythmia (measure of cardiac parasympathetic activity) (P>0.05) [9].

Chemical compound and disease context of Arrhythmia, Sinus

• Atenolol alone prolonged the mean R-R interval and increased sinus arrhythmia [10].
• CO2-dependent components of sinus arrhythmia from the start of breath holding in humans [11].
• This reduction in inhibitory neurotransmission to cardiac vagal neurons is likely responsible for the compromised respiratory sinus arrhythmia that occurs with ketamine anesthesia [12].
• Halothane and cardiac autonomic control in infants: assessment with quantitative respiratory sinus arrhythmia [13].
• Respiratory sinus arrhythmia during recovery from isoflurane-nitrous oxide anesthesia [14].

Biological context of Arrhythmia, Sinus

• Low dose atropine increased the magnitude of sinus arrhythmia and baroreflex responses [15].

Anatomical context of Arrhythmia, Sinus

• The comparative retention of sinus arrhythmia in children with atrial septal defect may relate to the small size of the right atrium or differences in myocardial compliance compared with adults [16].

Gene context of Arrhythmia, Sinus

• Surprisingly, however, a recent study in anesthetized rats paradoxically found an enhancement of cardiac vagal activity during inspiration, suggesting that rats have an inverted respiratory sinus arrhythmia (Rentero N, Cividjian A, Trevaks D, Pequignot JM, Quintin L, and McAllen RM. Am J Physiol Regul Integr Comp Physiol 283: R1327-R1334, 2002) [17].
• ADHD subjects showed less respiratory sinus arrhythmia than normal children but were similarly responsive to tone stimuli [18].
• Extent of sinus arrhythmia tended to be highest in quiet sleep (QS), lower in active or REM sleep (AS), and lowest in waking (AW), especially after 2 months of age [19].
• Pulmonary function, heart period (milliseconds between heart beats), and respiratory sinus arrhythmia (a measure of cardiac vagal tone) were assessed before drug administration and 45 min thereafter [20].
• Respiratory sinus arrhythmia as a predictor of outcome in major depressive disorder [21].

Analytical, diagnostic and therapeutic context of Arrhythmia, Sinus

• Medetomidine resulted in marked bradycardia, lasting as long as the sedation and the ECG revealed a sinus arrhythmia with sinoatrial and atrioventricular blocks grade I and II as a sign of interference with transduction [22].
• Here we show that fractal ventilation increases respiratory sinus arrhythmia (RSA) -- a mechanism known to improve ventilation/perfusion matching [23].

References