Diaphragmatic origin of false atrial dissociation evidenced through intra-vascular recordings.
In a patient suffering from respiratory insufficiency, an atrial dissociation pattern was found in the surface ECG recording, having the appearance of ectopic P waves, independent from sinus P waves and followed by microfibrillation waves of 450 ms duration. No electrical activity corresponding to the presumed ectopic P waves could be recorded from left and right atria. Conversely, such activity was recorded from the inferior vena cava (IVC) 1.5 cm below its junction with the right atrium, with a maximum amplitude; the occurrence and duration of these recordings appeared to be exactly synchronized with surface ectopic P waves/microfibrillation aspects and the inspiratory phase of respiration. Intravascular recording can be considered as a useful procedure to differentiate false and actual atrial dissociation.
Ebagosti
A
A
Department of Cardiology, Chemin des Bourrely, Marseille, France.
Gueunoun
M
M
Torresani
J
J
D000368:Aged; D003964:Diaphragm / Q000503:physiopathology*; D004562:Electrocardiography / Q000379:methods; D005189:False Positive Reactions; D006325:Heart Atria / Q000503:physiopathology; D006327:Heart Block / Q000503:physiopathology*; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D014682:Vena Cava, Inferior; D014939:Work of Breathing