title: Effect of atrial pressure increase on sinus node automaticity.
abstract: There is evidence suggesting that atrial electrophysiological properties may be changed by an acute increase in atrial pressure. The aim of the present study was to investigate the effect of alteration, in atrial pressure on sinus node recovery time. Twelve patients (8 men and 4 women, mean age 61.3 +/- 14.1 years) were included in this study. None of the patients had organic heart disease. Sinus node recovery time (SNRT) was measured following atrial pacing and atrioventricular (AV) pacing at sequential cycle lengths of 600, 545, 500, 461, 428, and 400 ms with two different AV intervals (150, 0 ms). Peak and minimal atrial pressure increased significantly from 8.5 +/- 2.8 to 20.1 +/- 2.9 mmHg (11.56 +/- 3.8 to 27.3 +/- 3.9 cmH2O) ( P=0.001) and from 2.06 +/- 1.69 to 5.33 +/- 2.9 mmHg (2.8 +/- 2.29 to 7.2 +/- 3.9 cmH2O), respectively (P=0.002) during AV interval modification. Sinus node recovery time did not change despite the increase in atrial pressure. Autonomic blockade had no effect on SNRT. This study demonstrates that atrial pressure increase does not significantly affect sinus node automaticity expressed by SNRT.
authors.affiliation: Second Department of Cardiology, "Evangelismos" General Hospital, Athens, Greece.
authors.forename: Michael
authors.initials: M
authors.lastname: Efremidis
authors.forename: Antonios
authors.initials: A
authors.lastname: Sideris
authors.forename: Gerasimos
authors.initials: G
authors.lastname: Filippatos
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Manolatos
authors.forename: Sotiris
authors.initials: S
authors.lastname: Xydonas
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Ikonomou
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Evangelou
authors.forename: Ilias
authors.initials: I
authors.lastname: Sioras
authors.forename: Michael
authors.initials: M
authors.lastname: Argyriou
authors.forename: Fotis
authors.initials: F
authors.lastname: Kardaras
mesh_terms: D000328:Adult; D000368:Aged; D016275:Atrial Function / Q000502:physiology*; D002304:Cardiac Pacing, Artificial; D004562:Electrocardiography / Q000379:methods; D004594:Electrophysiology / Q000379:methods; D005260:Female; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012849:Sinoatrial Node / Q000502:physiology*