TY - JOUR
T1 - The initial rate of troponin I release post-reperfusion reflects the effectiveness of myocardial protection during cardiac allograft preservation
AU - Ryan, Jonathon B.
AU - Hicks, Mark
AU - Cropper, Jonathan R.
AU - Garlick, Sarah R.
AU - Kesteven, Scott H.
AU - Wilson, Michael K.
AU - Feneley, Michael P.
AU - Macdonald, Peter S.
PY - 2003/6/1
Y1 - 2003/6/1
N2 - Objective: To determine if the initial rate of troponin I release post-reperfusion reflects the effectiveness of myocardial protection during cardiac allograft preservation. Methods: A porcine model of orthotopic heart transplantation was used. Data from two control groups (CON4 and CON14) and two treatment groups (CAR4 and CAR14) were analysed. Hearts in CON4 (n=6) and CAR4 (n=6) were subjected to 4 h of ischaemia while hearts in CON14 (n=3) and CAR14 (n=6) were subjected to 14 h of ischaemia. All hearts were arrested and stored in the same extracellular preservation solution. Both donor and recipient animals in the CAR4 and CAR14 groups received a single intravenous dose of cariporide (2 mg/kg), prior to explantation and reperfusion, respectively. Results: Mean (SEM) plasma troponin I levels (μg/ml) 3 h post-reperfusion were: CON4 210±52, CAR4 68±21, CON14 633±177, CAR14 346±93. On multiple linear regression analysis, the rate of troponin I release over the first 3 h post-reperfusion was significantly lower in hearts stored for 4 h compared to hearts stored for 14 h (P<0.0001) and in hearts treated with cariporide compared to control hearts (P=0.0017). Early graft function was superior in hearts treated with cariporide, when compared to control hearts stored for the same period of time. All of the CAR14 hearts could be weaned from cardiopulmonary bypass whereas none of the CON14 could be weaned (6/6 vs. 0/3; P=0.012). While all hearts stored for 4 h could be weaned, contractility, as measured by the preload recruitable stroke work (PRSW) relationship, was significantly better preserved in CAR4 hearts than in CON4 hearts (P<0.0001). Conclusions: The initial rate of troponin I release post-reperfusion is determined by the duration of cardiac allograft ischaemia. Altering the myocardial preservation strategy can reduce the rate of release. Such reductions are associated with improvements in early graft function. These findings validate the initial rate of troponin I release post-reperfusion as an end-point when comparing cardiac allograft preservation strategies. In addition, the present study provides indirect evidence that troponin I degradation during ischaemia-reperfusion is related to the accumulation of intracellular calcium.
AB - Objective: To determine if the initial rate of troponin I release post-reperfusion reflects the effectiveness of myocardial protection during cardiac allograft preservation. Methods: A porcine model of orthotopic heart transplantation was used. Data from two control groups (CON4 and CON14) and two treatment groups (CAR4 and CAR14) were analysed. Hearts in CON4 (n=6) and CAR4 (n=6) were subjected to 4 h of ischaemia while hearts in CON14 (n=3) and CAR14 (n=6) were subjected to 14 h of ischaemia. All hearts were arrested and stored in the same extracellular preservation solution. Both donor and recipient animals in the CAR4 and CAR14 groups received a single intravenous dose of cariporide (2 mg/kg), prior to explantation and reperfusion, respectively. Results: Mean (SEM) plasma troponin I levels (μg/ml) 3 h post-reperfusion were: CON4 210±52, CAR4 68±21, CON14 633±177, CAR14 346±93. On multiple linear regression analysis, the rate of troponin I release over the first 3 h post-reperfusion was significantly lower in hearts stored for 4 h compared to hearts stored for 14 h (P<0.0001) and in hearts treated with cariporide compared to control hearts (P=0.0017). Early graft function was superior in hearts treated with cariporide, when compared to control hearts stored for the same period of time. All of the CAR14 hearts could be weaned from cardiopulmonary bypass whereas none of the CON14 could be weaned (6/6 vs. 0/3; P=0.012). While all hearts stored for 4 h could be weaned, contractility, as measured by the preload recruitable stroke work (PRSW) relationship, was significantly better preserved in CAR4 hearts than in CON4 hearts (P<0.0001). Conclusions: The initial rate of troponin I release post-reperfusion is determined by the duration of cardiac allograft ischaemia. Altering the myocardial preservation strategy can reduce the rate of release. Such reductions are associated with improvements in early graft function. These findings validate the initial rate of troponin I release post-reperfusion as an end-point when comparing cardiac allograft preservation strategies. In addition, the present study provides indirect evidence that troponin I degradation during ischaemia-reperfusion is related to the accumulation of intracellular calcium.
KW - Heart transplantation
KW - Myocardial ischemia
KW - Myocardial reperfusion injury
KW - Myocardial stunning
KW - Sodium-hydrogen antiporter
KW - Troponin I
UR - http://www.scopus.com/inward/record.url?scp=0038724680&partnerID=8YFLogxK
U2 - 10.1016/S1010-7940(03)00114-3
DO - 10.1016/S1010-7940(03)00114-3
M3 - Article
C2 - 12829065
AN - SCOPUS:0038724680
SN - 1010-7940
VL - 23
SP - 898
EP - 906
JO - European Journal of Cardio-thoracic Surgery
JF - European Journal of Cardio-thoracic Surgery
IS - 6
ER -