A Protocol for Collecting Human Cardiac Tissue for Research

Abstract


 
 
 This manuscript describes a protocol at the University of Kentucky that allows a translational research team to collect human myocardium that can be used for biological research. We have gained a great deal of practical experience since we started this protocol in 2008, and we hope that other groups might be able to learn from our endeavors. To date, we have procured ~4000 samples from ~230 patients. The tissue that we collect comes from organ donors and from patients who are receiving a heart transplant or a ventricular assist device because they have heart failure. We begin our manuscript by describing the importance of human samples in cardiac research. Subsequently, we describe the process for obtaining consent from patients, the cost of running the protocol, and some of the issues and practical difficulties that we have encountered. We conclude with some suggestions for other researchers who may be considering starting a similar protocol.
 
 

Heart Failure in Humans Reduces Contractile Force in Myocardium From Both Ventricles

“…Figure 5A shows representative records measured for a LV preparation isolated from an organ donor. Consistent with previous results from human myocardium ( 15 ), force overshot the steady-state isometric value during the recovery phase ( 20 , 21 ). The k tr values increased approximately linearly with steady-state isometric force in every experimental group ( Figure 5B ).…”

“…Previous data from the laboratory ( 15 ) showed that heart failure had a greater impact on the contractile properties of the middle transmural region of the LV than on samples from the sub-epicardium or sub-endocardium. This study compared samples from the RV and the LV mid-myocardium to optimize the probability of detecting important effects.…”

“…As described by Haynes et al. ( 15 ), preparations were initially activated in a solution with a saturating Ca 2+ concentration of pCa 4.5. Maximum force was defined as the steady-state force measured during this trial.…”

“…The phosphorylation statuses of TnI, myosin binding protein-C (MyBP-C), and myosin regulatory light chain (RLC) were analyzed using gel electrophoresis as described by Haynes et al. ( 15 ). The samples used in these gels were saved from the homogenate after the mechanical disruption and chemical permeabilization procedures were used to prepare samples for contractile assays.…”

“…As previously described ( 15 ), the linear mixed model accounted for the hierarchical nested structure of the data (values obtained from multiple preparations from different regions of the same hearts) and had greater statistical power than a standard 2-way analysis of variance test for this type of experimental design. Post hoc analyses were performed using Tukey-Kramer corrections that took into account the number of hearts and the number of samples from each heart.…”