Donor-specific antibodies to class II antigens are associated with accelerated cardiac allograft vasculopathy: a three-dimensional volumetric intravascular ultrasound study.

BACKGROUND: Although a link between donor-specific antibodies against human leukocyte antigens type II (DSA II+) and transplant glomerulopathy has been clearly established, its role in cardiac allograft vasculopathy (CAV) is unclear.
METHODS: Donor-specific antibodies were evaluated using solid-phase single-antigen bead assay before transplantation in 51 heart transplant recipients. Coronary angiography and three-dimensional intravascular ultrasound were performed at baseline and approximately 1 year after the baseline examination.
RESULTS: There were 4 (7.8 %), 11 (21.5%), and 2 (3.9%) patients who had DSA against donor class I (DSA I+), DSA II+, or both, respectively. All patients had negative complement-dependent cytotoxic crossmatch. There was accelerated progression of CAV in the DSA II+ group demonstrated by accelerated progression in plaque index (plaque volume/vessel volume) compared to patients with no DSA II+ antibodies (13.8% [12%] vs. -7.9% [37%], P=0.01). The development of any angiographic CAV was also more common in DSA II+ patients as compared to the DSA- patients at 4 years (100% [0%] vs. 64.2% [10%], P=0.05). All other traditional risk factors for CAV or immunosuppression were similar between the groups (P>0.2 for all).
CONCLUSIONS: This is the first preliminary study demonstrating that heart transplant recipients with preformed class II DSA may be at an increased risk for accelerated CAV as detected by consecutive volumetric three-dimensional intravascular ultrasound.