Introduction: Rapidly progressive, or fulminant cardiac allograft vasculopathy (CAV) is associated with a high risk of graft failure and mortality in heart transplant (HTx) patients. (1) Since clinical presentation is often dramatic, patients do not typically undergo intravascular imaging, especially not serial assessments of progressively evolving coronary changes.

Case report: We present a case of a 59-year-old HTx recipient who presented in April 2021 with severe dyspnea, three years following HTx. Echocardiography revealed left ventricular (LV) wall thickening (IVSd 13 mm) with a severely reduced ejection fraction (LVEF) of 30%, restrictive filling pattern, and high values of NT-proBNP (>35000 ng/L). Urgent endomyocardial biopsy and coronary angiography were performed. Angiography showed severe CAV, and optical coherence tomography (OCT) of the left anterior descending artery (LAD) showed multiple coronary lesions, including wall edema with side-branch compromise, intimal hyperplasia, erosions, fissure, and spasm (Figure 1). Immunohistopathological analysis showed no signs of cellular or antibody-mediated rejection (AMR), however Luminex^® revealed a very high mean fluorescence intensity for class II donor-specific anti-HLA antibodies, supporting the clinical suspicion of AMR and related accelerated CAV. Anti-rejection treatment was immediately initiated, along with dual antiplatelet therapy, low-molecular weight heparin, and substitution of cyclosporine with tacrolimus. Anti-rejection therapy, consisting of intravenous immunoglobulins, pulse corticosteroids, and plasmapheresis resulted in significant clinical improvement, improvement in LV function (LVEF 45%), and decrease in NT-proBNP values (16249 ng/L at discharge). Follow-up coronary angiography with OCT showed evolution of coronary lesions including bright spots, necrotic intimal lesions with spasm, and layered fibrotic plaques (Figure 1).

Conclusion: Serial intravascular imaging using OCT in patients with rapidly progressive CAV can provide in vivo insight into the evolution of coronary changes, which may help us better understand the pathogenesis of this form of CAV.