Predictive Factors for Pulmonary Homograft Dysfunction After Ross Surgery: A 20-Year Follow-up

Effect of cardiac graft rejection on semilunar valve function: implications for heart valve transplantation

BACKGROUND

The treatment of neonates with unrepairable heart valve dysfunction remains an unsolved problem because there are no growing heart valve replacements. Heart valve transplantation is a potential approach to deliver growing heart valve replacements. Therefore, we retrospectively analysed the semilunar valve function of orthotopic heart transplants during rejection episodes.

METHODS

We included children who underwent orthotopic heart transplantation at our institution and experienced at least one episode of rejection between 1/1/2010 and 1/1/2020. Semilunar valve function was analysed using echocardiography at baseline, during rejection and approximately 3 months after rejection.

RESULTS

Included were a total of 31 episodes of rejection. All patients had either no (27) or trivial (4) aortic insufficiency prior to rejection. One patient developed mild aortic insufficiency during a rejection episode (P = 0.73), and all patients had either no (21) or trivial (7) aortic insufficiency at follow-up (P = 0.40). All patients had mild or less pulmonary insufficiency prior to rejection, which did not significantly change during (P = 0.40) or following rejection (P = 0.35). Similarly, compared to maximum pressure gradients across the valves at baseline, which were trivial, there was no appreciable change in the gradient across the aortic valve during (P = 0.50) or following rejection (P = 0.42), nor was there any meaningful change in the gradient across the pulmonary valve during (P = 0.55) or following rejection (P = 0.91).

CONCLUSIONS

This study demonstrated that there was no echocardiographic evidence of change in semilunar valve function during episodes of rejection in patient with heart transplants. These findings indicate that heart valve transplants require lower levels of immune suppression than orthotopic heart transplants and provide partial foundational evidence to justify future research that will determine whether heart valve transplantation may deliver growing heart valve replacements for children.

The Ross procedure and valve-sparing root replacement procedures in the adult patient: do guidelines follow the evidence?

Prosthetic aortic valve replacements have long been the mainstay of valvular surgery due to their favorable outcomes and low operative complexity. Yet, mechanical valves require lifelong anticoagulation, whereas bioprosthetic valves increase the risk for earlier and more frequent reoperation. Alternative reconstructive techniques have been proposed to address these challenges. These include valve-sparing root replacement procedures if the native aortic valve can be salvaged, and the Ross procedure, which nearly eliminates prosthetic valve-related thromboembolism, anticoagulation-related hemorrhage and endocarditis. Both procedures are technically more complex and thus subject to surgeons' volume and expertise compared to conventional aortic valve replacements. However, they are associated with more favorable outcomes compared to aortic valve replacements if performed by experienced surgeons, especially in younger patients. Nevertheless, despite the growing high-quality literature supporting both procedures, existing multi-society guidelines fail to acknowledge the strength of evidence in support of valve-sparing root replacement procedures and the Ross procedure. In this review, we summarize the existing long-term evidence for the use of each procedure, describe the current guidelines for the treatment of aortic valve pathology, and propose the reevaluation of guidelines based on the available clinical evidence.