Revealing a new mode of sensitization induced by mechanical circulatory support devices: Impact of anti-AT 1 R antibodies.

BACKGROUND: Increased levels of angiotensin II type 1 receptor (AT1 R) antibody have been shown to be associated with allograft rejection. This study aims to determine the rate of development of antibody to AT1 R after mechanical circulatory support device (MCS) implantation, and if the development of strong binding AT1 R antibodies is associated with survival.

METHODS: Eighty-eight patients who had one MCS implantation were accessed based on serum availability. Mechanical circulatory support devices in this cohort included pneumatic bilateral paracorporeal ventricular assist device, continuous flow left ventricular assist device, and total artificial heart.

RESULTS: Of 88 patients, seven patients had AT1 R antibodies ≥40 U/mL preimplantation. For 81 patients who had AT1 R antibodies <40 U/mL, the median value was 8 U/mL. Of these 81 patients, AT1 R antibody levels in 55 (68%) patients reached the saturated concentration (≥40 U/mL) postimplantation (P < .0001), with the highest percentage of patients with the saturated level of AT1 R antibody observed in the pneumatic bilateral paracorporeal ventricular assist device group. Compared to patients without the saturated level of AT1 R antibodies, patients with the saturated AT1 R antibody level had lower 18-month survival (P = .040).

CONCLUSION: Mechanical circulatory support devices implantation significantly increases AT1 R antibody levels. The saturated level of AT1 R antibodies is associated with lower patient survival postimplantation.