The effect of uraemia on the duration of arrhythmias in the context of cardioprotective ischaemic conditioning strategies.
BACKGROUND
Sudden cardiac death is a leading cause of death in patients with chronic kidney disease and end stage renal disease. Ischaemic conditioning strategies confer profound myocardial protection and, in the absence of uraemia, have been reported to reduce myocardial dysrhythmias. Recent data confirms that ischaemic conditioning can protect the uraemic heart. However, the effect of uraemia on myocardial arrhythmogenesis in the context of ischaemia-reperfusion injury and whether ischaemic conditioning can modulate this is unknown.


OBJECTIVE
We investigated the effect of underling chronic uraemia on the duration of arrhythmias in the context of cardioprotective ischaemic conditioning strategies.


METHODS
We examined the effect of chronic uraemia on arrhythmias occurring in the context of myocardial ischaemia-reperfusion injury and the ability of ischaemic preconditioning (IPC), remote ischaemic preconditioning (RIPC) and ischaemic postconditioning (iPOST) to suppress arrhythmogenesis in uraemic and non-uraemic animals.


RESULTS
IPC led to a reduction in the frequency and duration of arrhythmias occurring during ischaemia and reperfusion. Neither RIPC nor iPOST affected the duration or frequency of ischaemic or reperfusion arrhythmias. Underlying uraemia did not alter the frequency or duration of ischaemic arrhythmias in any of the experiments however it was associated with a reduction in reperfusion arrhythmia duration in the IPC and iPOST experiments.


CONCLUSIONS
These studies demonstrate that underlying chronic uraemia does not reduce the threshold for arrhythmia timing or duration resulting from myocardial ischaemia-reperfusion and underlying uraemia did not alter the effects of these cardioprotective ischaemic conditioning strategies in the context of arrhythmia duration.


CONCLUSIONS
This novel work in a rodent model of chronic uraemia establishes that underlying uraemia does not increase the susceptibility to myocardial ischaemia-reperfusion induced arrhythmias. When compared with the non-uraemic heart, the uraemic heart has a similar response to the effects of ischaemic conditioning strategies in terms of their effect on arrhythmia timing and duration.
Department of Translational Medicine and Therapeutics , William Harvey Research Institute, Queen Mary University London , London , UK.
Kieran
K
McCafferty
Department of Translational Medicine and Therapeutics , William Harvey Research Institute, Queen Mary University London , London , UK.
Conor J
CJ
Byrne
Department of Translational Medicine and Therapeutics , William Harvey Research Institute, Queen Mary University London , London , UK.
Julius
J
Kieswich
Department of Translational Medicine and Therapeutics , William Harvey Research Institute, Queen Mary University London , London , UK.
Martin
M
Raftery
Department of Translational Medicine and Therapeutics , William Harvey Research Institute, Queen Mary University London , London , UK.
Christoph
C
Thiemermann
Department of Translational Medicine and Therapeutics , William Harvey Research Institute, Queen Mary University London , London , UK.
Muhammad M
MM
Yaqoob
Arrhythmias; Renal Disease