A heart transplant, or a cardiac transplant, is a surgical transplant procedure performed on patients with end-stage heart failure or severe coronary artery disease. As of 2008 the most common procedure is to take a working heart from a recently deceased organ donor (cadaveric allograft) and implant it into the patient. The patient’s own heart is either removed (orthotopic procedure) or, less commonly, left in place to support the donor heart (heterotopic procedure). Post-operation survival periods average 15 years. Heart transplantation is not considered to be a cure for heart disease, but a life-saving treatment intended to improve the quality of life for recipients. One of the important measure for managing patients post surgery is the reaction of the immune system to the transplanted heart (organ rejection). Current methods require some lab test, or biopsies. The latter is dangerous. Using Myocardial Solutions’ products, many measurements of change in the tissue of the heart can help determine whether a rejection process is occurring and its extent. One of these indicators is the changes in contractility as measured by strain.