2012 annual meeting & cardiothoracic forum - Society for ...

JOINT ANNUAL MEETING 2012 ABSTRACTS
020 The Right Ventricle Performs as Well as the Left Ventricle in the
DCD Donor Heart
Authors: Fouad Taghavi 1 C.E. Woods 1 S.R. Large 2 E. Ashley 1 A. Ali 2
1 Stanford University, USA; 2 Papworth Hospital NHS Foundation Trust, United
Kingdom
Objectives: Heart transplantation from DCD donors is not undertaken due to
concerns over ischemic injury. We have demonstrated in animal models that the
DCD heart can be resuscitated and transplanted, however initial right ventricular
(RV) pressure-volume (PV) loops were morphologically abnormal. Myocardial failure
is an important problem after heart transplantation, RV failure is most common,
although its mechanisms remain poorly understood. RV and left ventricle (LV) have
different embryonic origins. To investigate further we compared function of both
RV&LV in control and DCD hearts. To study organ function we used pressure-volume
(PV) loops. To study function at a molecular level we analyzed intracellular calcium
handling and contraction.
Methods: Male Sprague-Dawley rats were subjected to DCD heart resuscitation
using ECMO 15 minutes after circulatory arrest. RV&LV PV loop measurements were
made. Myocytes were isolated separately and loaded with calcium indicator Fluo-5f.
Sarcomere length (SL) was measured during contraction to assess contractility.
Intracellular calcium (deltaF/F) was measured epifluorescently. Sham operated
animals were used as control.
Results: RV function decline mirrored LV function decline from control to DCD with
no statistical differences seen between RV&LV when looking at: end systolic
pressure volume relationship, preload recruitable stroke work and contractility index
(n>7 animals in each group). At a molecular level RV function mirrored LV function
in control and DCD when looking at: myocyte %SL change, speed of contraction and
deltaF/F (n>60 in each group).
Conclusions: Our initial concerns over abnormal RV PV loop morphology in DCD
hearts have been put to rest. The RV does not perform worse than the LV after DCD
heart resuscitation. Even though the RV & LV have different embryonic origins,
measuring LV alone in this model is sufficient in accessing the DCD heart. Our
efforts must now focus on optimising the DCD heart for potential transplantation.
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