Echocardiography improves detection of rejection after heterotopic mouse cardiac transplantation.
BACKGROUND
Current assessments of cardiac rejection in murine transplant models rely on subjective estimates of the force of the palpable heart beat that have limited sensitivity and precision.


METHODS
We used 2-dimensional echocardiography to evaluate changes in left ventricular posterior wall thickness (PWT) in a heterotopic cardiac mouse transplant model of rejection. Nine allografts and 6 isografts were imaged daily for 6 days and harvested. Thirteen allografts were imaged daily and harvested at day 3.


RESULTS
Intraobserver variability on PWT was 0.003 +/- 0.09 mm, interobserver variability 0.09 +/- 0.11 mm. Allograft PWT increased after transplantation (0.74 +/- 0.02 mm to 1.28 +/- 0.05 mm at day 5, P <.0001). For isografts, PWT remained constant (0.73 +/- 0.03 mm to 0.85 +/- 0.01 mm) after an initial increase at day 1. Palpation failed to identify rejection at day 3 whereas PWT was already increased (1.15 +/- 0.02 mm in the allografts at day 3 vs 0.85 +/- 0.02 mm in the isografts, P <.0001). There was a relation between histologic score and PWT (P <.0001).


CONCLUSIONS
Two-dimensional echocardiography allows the noninvasive detection and follow-up of cardiac rejection after transplantation. It eliminates the subjectivity of palpation and provides quantitative and reliable indices of rejection.
Scherrer-Crosbie
Marielle
M
Cardiology Division, Department of Medicine, Massachusetts General Hospital, 02114, USA. marielle@crosbie.com
Glysing-Jensen
Troels
T
Fry
Stefanie J
SJ
Vançon
Anne-Claire
AC
Gadiraju
Silpa
S
Picard
Michael H
MH
Russell
Mary E
ME
D000818:Animals; D004195:Disease Models, Animal; D004452:Echocardiography; D005240:Feasibility Studies; D006084:Graft Rejection / Q000000981:diagnostic imaging* / Q000453:epidemiology; D016027:Heart Transplantation / Q000276:immunology; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008955:Models, Cardiovascular; D009206:Myocardium / Q000473:pathology; D015588:Observer Variation; D010173:Palpation; D011184:Postoperative Period; D011300:Preoperative Care; D013318:Stroke Volume / Q000502:physiology; D016042:Transplantation, Heterotopic; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging / Q000453:epidemiology