Long-term follow-up will be needed to ensure the lifetime risks of a prosthetic valve or valve repair are balanced against any benefits attributable to 16.4. Better Options for Intervention: Stage D Better options are needed for valve repair and replace- ment. The timing of intervention is based on the bal- ance between outcomes with native valve disease and the risk and long-term durability of the valve after in- tervention. As valve repair and replacement options improve, the balance will shift toward earlier interven- tion. A valve substitute is needed that can be safely and reliably implanted, is nonthrombogenic, has hemody- namics similar to a normal native valve, and is dura- ble. Transcatheter valve procedures offer the promise of safe implantation and excellent hemodynamics, but long-term durability beyond 5 years is not yet known. In patients who require mechanical valve replacement, oral therapy is needed that provides effective anticoag- ulation with a low risk of complications and no negative impact on quality of life. Moderate to severe VHD is present in 2.5% of the US population and increases in prevalence with age. The disease affects between 4% and 9% of those 65 to 75 years of age and 12% to 13% of those >75 years of age. Many of these patients require surgical or in- terventional procedures. However, even with interven- tion, overall survival is lower than expected, and the risk of adverse outcomes attributable to VHD is high, because of both limited options for restoring normal valve function and failure to intervene at the optimal time point in the disease course. Research is urgently needed on almost every aspect of VHD to ensure that patients who already have VHD receive optimal thera- py and to prevent VHD in those at risk. 