Optimal pacing modes after cardiac transplantation: is synchronisation of recipient and donor atria beneficial?
OBJECTIVE
To investigate the response of the transplanted heart to different pacing modes and to synchronisation of the recipient and donor atria in terms of cardiac output at rest.


METHODS
Doppler derived cardiac output measurements at three pacing rates (90/min, 110/min and 130/min) in five pacing modes: right ventricular pacing, donor atrial pacing, recipient-donor synchronous pacing, donor atrial-ventricular sequential pacing, and synchronous recipient-donor atrial-ventricular sequential pacing.


METHODS
11 healthy cardiac transplant recipients with three pairs of epicardial leads inserted at transplantation.


RESULTS
Donor atrial pacing (+11% overall) and donor atrial-ventricular sequential pacing (+8% overall) were significantly better than right ventricular pacing (p < 0.001) at all pacing rates. Synchronised pacing of recipient and donor atrial segments did not confer additional benefit in either atrial or atrial-ventricular sequential modes of pacing in terms of cardiac output at rest at these fixed rates.


CONCLUSIONS
Atrial pacing or atrial-ventricular sequential pacing appear to be appropriate modes in cardiac transplant recipients. Synchronisation of recipient and donor atrial segments in this study produced no additional benefit. Chronotropic competence in these patients may, however, result in improved exercise capacity and deserves further investigation.
Parry
G
G
Department of Cardiology, Freeman Hospital, Newcastle upon Tyne.
Malbut
K
K
Dark
J H
JH
Bexton
R S
RS
D000293:Adolescent; D000328:Adult; D016275:Atrial Function / Q000502:physiology*; D002302:Cardiac Output / Q000502:physiology; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D005260:Female; D006321:Heart / Q000503:physiopathology; D016027:Heart Transplantation / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged