CHANGES IN HEART ALLOCATION FOR TRANSPLANTATION IN THE US AND WORLDWIDE: OPTIONS FOR A BETTER SOLUTION
Maryl R. Johnson, M.D., University of Wisconsin-Madison, Madison, WI, USA
Only around 70 heart-kidney transplants are performed worldwide annually, representing 2-3% of heart transplants and 0.5% of kidney transplants. However, due to the shortage of donor kidneys (in the United States over 95,000 people are waiting for a donor kidney and only 11,000 deceased donor kidney transplants are performed annually), it is important that all candidates receiving a heart-kidney transplant truly need the kidney. A creatinine > 1.5 increases the risk of 1-year mortality following heart transplantation and heart transplant recipients who require dialysis during the transplant hospitalization have a hospital mortality as high as 40% and a 1-year survival of <75%. Heart-kidney transplant recipients have similar survival, less rejection and less cardiac allograft vasculopathy compared to heart only transplant recipients. Of note, heart transplant recipients requiring dialysis pre-transplant have a 1-year survival following heart transplant alone of only 50%, so heart transplant alone should generally not be performed in this patient group. Available data suggest that combined heart-kidney transplantation should be considered for heart transplant candidates: 1) on pre-transplant dialysis or with a creatinine clearance < 30 or creatinine > 2.5; 2) with a longer duration of renal insufficiency; or, 3) with comorbid diseases known to cause renal disease such as hypertension and diabetes mellitus. However, due to poor outcomes, heart-kidney transplant should not be performed in recipients >60 years or with peripheral vascular disease or a peak reactive antibody level > 30%.