PMID- 23928033
OWN - NLM
STAT- MEDLINE
DCOM- 20140904
LR  - 20140113
IS  - 1444-2892 (Electronic)
IS  - 1443-9506 (Linking)
VI  - 23
IP  - 1
DP  - 2014 Jan
TI  - Arrhythmogenicity of hypothermia - a large animal model of hypothermia.
PG  - 82-7
LID - S1443-9506(13)01057-3 [pii]
LID - 10.1016/j.hlc.2013.07.001 [doi]
AB  - BACKGROUND: Therapeutic hypothermia (TH) is used to mitigate cerebral injury 
      after an out of hospital cardiac arrest. There is a perceived risk of increased 
      arrhythmias with temperatures lower than the current target of 32-34 degrees C for TH. 
      This study sought to develop and investigate the electrophysiological changes in 
      a sheep model of systemic hypothermia regarding the susceptibility to ventricular 
      arrhythmias. METHODS: Ten sheep underwent systemic hypothermia using a 
      venous-venous extra-corporeal circuit whilst instrumented with a 12 lead ECG. An 
      epicardial sock recorded potentials to 30 degrees C (N=10) or 26 degrees C (N=6). Activation 
      times (AT) and Activation Recovery Intervals (ARI) were calculated using custom 
      software. RESULTS: The AT and ARI were significantly prolonged with increased 
      heterogeneity during hypothermia. This effect was most pronounced between 
      normothermia and 34 degrees C during sinus rhythm (SR). For ventricular pacing (VP) 
      however heterogeneity continued to increase with progressive hypothermia. 
      CONCLUSIONS: Hypothermia causes a significant increase in the heterogeneity of 
      depolarisation and repolarisation. There is evidence to suggest that SR is 
      protective with most of the increase in heterogeneity occurring with cooling to 
      34 degrees C. This raises the possibility that the current target temperatures for 
      therapeutic hypothermia may be safely lowered to provide a gain in cerebral 
      protection.
CI  - Copyright (c) 2013. Published by Elsevier B.V.
FAU - Bassin, Levi
AU  - Bassin L
AD  - Cardiac Technology Centre, Kolling Institute of Medical Research, University of 
      Sydney, Royal North Shore Hospital, St Leonards, NSW 2065, Australia; Faculty of 
      Medicine, Royal Hobart Hospital Clinical School, University of Tasmania, Hobart, 
      Tasmania 7000, Australia. Electronic address: levi.bassin@gmail.com.
FAU - Yong, Ah Chot
AU  - Yong AC
AD  - Faculty of Medicine, Royal Hobart Hospital Clinical School, University of 
      Tasmania, Hobart, Tasmania 7000, Australia.
FAU - Kilpatrick, David
AU  - Kilpatrick D
AD  - Faculty of Medicine, Royal Hobart Hospital Clinical School, University of 
      Tasmania, Hobart, Tasmania 7000, Australia.
FAU - Hunyor, Stephen Nicholas
AU  - Hunyor SN
AD  - Cardiac Technology Centre, Kolling Institute of Medical Research, University of 
      Sydney, Royal North Shore Hospital, St Leonards, NSW 2065, Australia.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20130806
PL  - Australia
TA  - Heart Lung Circ
JT  - Heart, lung & circulation
JID - 100963739
SB  - IM
MH  - Animals
MH  - *Arrhythmias, Cardiac/etiology/physiopathology
MH  - Disease Models, Animal
MH  - *Electrocardiography
MH  - Heart Arrest/etiology/physiopathology
MH  - Hypothermia, Induced/*adverse effects
MH  - Sheep
OTO - NOTNLM
OT  - Cardiac arrhythmias
OT  - Cardiac electrophysiology
OT  - Hypothermia
OT  - Therapeutic hypothermia
EDAT- 2013/08/10 06:00
MHDA- 2014/09/05 06:00
CRDT- 2013/08/10 06:00
PHST- 2013/05/19 00:00 [received]
PHST- 2013/06/29 00:00 [revised]
PHST- 2013/07/02 00:00 [accepted]
PHST- 2013/08/10 06:00 [entrez]
PHST- 2013/08/10 06:00 [pubmed]
PHST- 2014/09/05 06:00 [medline]
AID - S1443-9506(13)01057-3 [pii]
AID - 10.1016/j.hlc.2013.07.001 [doi]
PST - ppublish
SO  - Heart Lung Circ. 2014 Jan;23(1):82-7. doi: 10.1016/j.hlc.2013.07.001. Epub 2013 
      Aug 6.