Current Status of Cardiac Transplantation in the 21st Century

Advanced heart failure is an entity where irreversible structural heart disease is associated with persistent, refractory symptoms and quantitative decrease in cardiopulmonary capacity. Despite advanced and comprehensive medical therapy, patients are at high risk of death due to cardiogenic shock or cardiac arrest. Heart transplantation was developed as a surgical intervention to replace the failing recipient heart with a healthy heart from a recently deceased donor. In this article, we discuss the current state of cardiac transplantation, more than 5 decades after the first human cardiac transplantation was performed. Apart from an historical overview of the development of surgical techniques, we focus on appropriate patient selection, pretransplant evaluation, and recognition and treatment of post-transplant complications.

Orthotopic heart transplantation in children

Heart transplantation is a relatively infrequent but technically demanding procedure in pediatric cardiac surgery. Orthotopic heart transplantation is often offered to older children or adolescents following multiple previous operations, but with advances in intensive care, diagnostics, and management, more infants with complex congenital heart diseases are being listed for transplantation. Primary cardiomyopathies remain the most common indication. Outcomes following cardiothoracic transplantation have improved steadily in recent times. Donor availability has been helped by increasing public awareness and donation after cardiac death, especially of lungs, increasing the number of patients benefiting from heart and/or lung transplantation. While there are still insufficient donors to meet the current needs, effective devices to bridge patients to transplantation are now widely used. Although the many advances have improved the outlook of transplantation, there are still difficulties that have not changed over time. Nevertheless, heart transplantation in children carries a reasonably good survival rate over the entire spectrum of recipient heart conditions. We discuss the salient features of acceptance of an organ and the technical aspects of both simple and complex heart transplantation in children.

Abstract 12422: Evaluation of RV and LV Mass by CMR and Comparison to Recipient Heart Following Heart Transplant; The First-Ever CMR Human Autopsy Study

Introduction: CMR is considered the ‘gold standard’ for noninvasive LV and RV mass quantitation. This concept is predominantly based on GRE sequences yet never validated in humans undermining its credibility. SSFP offers superior image contrast potentially redefining the CMR gold standard for mass. Objective: To establish correlations between SSFP-CMR LV and RV mass vs. pathology mass using Htx pts. Methods: Over 3 years, 68 pts were evaluated including 48 HTx explants obtained immediately from the OR upon HTx. They were prepared (removed PM/AICD and/or LV/RVAD) and scanned ex vivo via SSFP for CMR LV/RV mass (1.5T GE, WI). Via an A utomatic T hresholding program for segmentation with M anual T rimming (ATMT) of extraneous cardiac tissue a 3D LV model was generated. The weight of total heart including papillary and trabeculae for LV and RV was measured via high-fidelity scale. Correlations were between 3D CMR vs. pathology with B-A plots. A separate cohort of 20 non-Htx pts underwent in vivo validation. Results: Of 48 Htx pts, 3 (6%) were excluded due to poor images (peri-surgical destruction) leaving 45 (94%) for analysis. Correlations: 1) Total CMR 3D mass (448±116g) vs. total pathology mass (444±118g; r=0.99, p<.001); 2) 3D CMR-LV mass (297±95g) vs. pathology-LV mass (308±96g; r =0.95, p<.001) 3) 3D CMR-RV mass (152±44g) vs pathology-RV mass (132±41g; r = 0.76, p<.001). The equation y = 1.01x - 6.6b regressed the LV (r = 0.95). Avg bias between CMR and pathology for total, LV and RV mass was +4.4g. For the validation cohort LVEDV r=0.99; LVESV r= 0.99. Conclusions: SSFP-CMR accurately defines total cardiac, LV and RV mass as compared to explanted hearts (despite variable surgical removal of instrumentation). Thus, while GRE was the original ‘gold standard’ for LV mass, SSFP, despite its universal acceptance as the ‘ de facto gold standard is now formally validated in a first-ever human autopsy study. Further, the regression equation now includes , not excludes papillary and trabecular mass.