Restenosis rates for drug-eluting stents used in treating small vessel cardiac allograft vasculopathy after orthotopic heart transplantation

Background: Cardiac allograft vasculopathy (CAV) is associated with increased mortality in patients with orthotopic heart transplantation (OHT). In addition to immunosuppression, CAV can be treated with percutaneous coronary intervention (PCI) with drug eluting stents (DES) for focal lesions. There is a paucity of data on the rate of DES restenosis in patients with small vessel CAV. Methods: This was a retrospective observational study of 101 coronary vessels treated with a DES diameter of 2.5 mm or less (small vessels) in 61 OHT patients compared to 72 coronary vessels treated with a DES diameter of >2.5 mm (large vessels) in 44 OHT patients at a single center between 2004 and 2022. Baseline demographic data, angiographic characteristics, and clinical outcomes were analyzed. Results: At an average of 1.6 years after DES placement, follow-up angiography revealed in-stent restenosis in 36 (39 %) small vessel interventions and 11 (17 %) large vessel interventions (p = 0.003). Long term mortality did not differ between the groups (59 % vs 59 % at a median of 4.7 [IQR 2.4–7.8] years follow up). Conclusion: DES restenosis rates are high in small vessel CAV. Additional studies specifically examining PCI in small vessel CAV as well as the potential role for newer treatment strategies for CAV are warranted.