Long-Term Survival after Heart Transplantation Depends on Proper Outward Remodeling of Epicardial Arteries with Cardiac Allograft Vasculopathy

Purpose Long term survival after heart transplantation (HTx) is hampered by chronic rejection. The immune reaction in the coronary arteries leads to Cardiac Allograft Vasculopathy (CAV). This is the first study to describe histological changes in the artery wall in a quantitative way in relation to time post HTx. Methods and Materials Coronary arterial cross sections from 51 HTx patients, made available after autopsy, were stained (immuno)histochemically. Histological CAV stages (H-CAV 0-3) were identified and all arteries classified accordingly. The relative surface area of the media (M), neo-intima (NI), NI-luminal layer (NI-LL), NI-smooth muscle cell layer (NI-SMC), and the lumen was measured digitally (n=38). Results The H-CAV stage of the patients was higher with increasing post HTx time. Stenosis of the lumen was seen in 11 patients, predominantly scored as H-CAV 1&2. Patients that died within 2 years post HTx (n=25) showed a significant correlation between time post HTx and all vessel layer areas. This correlation was negative for luminal area and M, and positive for the NI, NI-LL, and NI-SMC (all p Conclusions Distinct patterns of CAV and arterial remodeling can be observed between patients that die within 2 years after HTx and long term HTx survivors. In the first group, CAV induces luminal stenosis without compensatory remodeling. In long term HTx survivors compensatory outward remodeling of the vessel wall seems to prevent luminal narrowing due to CAV. [ figure 1 ]