Troponin T and I are not reliable markers of cardiac transplant rejection.
OBJECTIVE
Heart transplant recipients undergo a number of invasive endomyocardial biopsies to screen for rejection. Serum assays of troponin T and/or I may provide a less invasive alternative. The purpose of this study was to evaluate troponin T and I as markers of cardiac transplant rejection.


METHODS
We conducted a prospective analysis comparing troponin T and I levels to biopsy results in heart transplant recipients. Plasma was assayed for troponin T and I preoperatively, on the first 3 postoperative days, and with each subsequent biopsy.


RESULTS
Twenty-nine patients entered the study. A total of 173 biopsies were performed at a mean follow-up of 129+/-9 days (range: 12-564 days). There were two rejection episodes (> or = grade 3), one in each of two patients. There were no significant relationships between troponin T or I and biopsy-proven rejection (> or = grade 3; P=0.59 and 0.54, respectively). There were also no correlations between troponin T or I levels and biopsy grade (P=0.40 and 0.92, respectively). Troponin T and I levels peaked on postoperative day 1 and fell to baseline over long-term follow-up with no peak in serum markers associated with rejection episodes. Donor ischemic time was significantly correlated to troponin T on postoperative days 1-3 (r=0.58, P=0.005; r=0.61, P=0.004; and r=0.61, P=0.003, respectively).


CONCLUSIONS
Troponin T and I are not useful indicators of cardiac rejection, but do correlate with donor heart ischemic injury.
Division of Cardiac Surgery, The University of Alberta Hospital, 2D2.18 W.C. Mackenzie Health Sciences Centre, 8440-112 Street, Edmonton, Alta T6G 2B7, Canada. jmullen@ualberta.ca
J C
JC
Mullen
M J
MJ
Bentley
K D
KD
Scherr
S G
SG
Chorney
N I
NI
Burton
W J
WJ
Tymchak
A
A
Koshal
D L
DL
Modry
D015415:Biomarkers / Q000097:blood; D001706:Biopsy; D005260:Female; D006084:Graft Rejection / Q000097:blood / Q000175:diagnosis*; D016027:Heart Transplantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D019210:Troponin I / Q000097:blood*; D020107:Troponin T / Q000097:blood*
D015415:Biomarkers; D019210:Troponin I; D020107:Troponin T