**5. Tricuspid valve abnormalities**

Heart transplantation is often associated with tricuspid regurgitation (TR). Structural or functional factors can be associated with TR. The biatrial technique of heart transplantation is associated with more TR than the bicaval technique. The incidence of post-transplantation TR has decreased since the introduction of the bicaval anastomosis implantation technique by Yacoub et al. in 1989 [31, 32]. This was believed to be related to the reduced right atrial pressure and preserved right atrial size during the use of a bicaval rather than a biatrial anastomosis technique [33]. Other possible causes of TR include (1) allograft dysfunction with right ventricular dilatation due to poor preservation, reperfusion injury, donor factors, or rejection; (2) pulmonary hypertension; (3) severe donor-recipient size mismatch; and (4) structural damage during endomyocardial biopsy [34–36].

It has been reported that prophylactic tricuspid valve annuloplasty of the donor heart is durable and offers a survival advantage in the perioperative and long-term periods [37, 38]. Considering the simplicity and safety of tricuspid valve annuloplasty and its advantages, there should be a low threshold when considering the procedure as a routine adjunct to heart transplantation.

### **6. Conclusion**

The appropriate utilization of the valve repair/replacement technique with precise assessment of an additional warm ischemic time necessitates careful consideration within each transplant center and each patient potentially willing to accept an allograft with valve disease in the context of the expected allograft cold ischemic time.

Bench valvular replacement or repair of donor allografts during cold ischemia is feasible, and its implementation could enable the use of previously unsalvageable hearts, thus expanding the donor organ pool. Bench valve surgery, combined with proper donor and recipient selection, will enable the expansion of the donor pool to provide high-quality donor allografts that otherwise would have been declined.
