A lower INR goal of 1.5-2.0 for the On-X valve in the aortic position significantly reduced clots, bleeding, and stroke compared to standard INR (9 vs 12 per patient-years).
Does a lower INR goal of 1.5-2.0 reduce the combined endpoint of clots, bleeding events, and stroke in patients with an On-X mechanical valve at the aortic position compared to a standard INR goal?
The On-X mechanical aortic valve allows for a lower INR goal of 1.5-2.0, which significantly reduces the combined risk of clots, bleeding, and stroke compared to standard INR targets.
Absolute Event Rate: 9% vs 12%
The On-X valve is a newer generation mechanical bileaflet valve. Its key features include the use of pure pyrolytic carbon (devoid of silicon), a length-to-diameter ratio similar to a native valve, an inlet flared orifice, a leaflet opening up to 90 degrees, a shorter leaflet closing angle, a 2-point leaflet contact, and an actuated pivot. These features have translated into increased strength, improved valve hemodynamics, reduced hemolysis, and thrombogenicity. The 2014 American Heart Association/American College of Cardiology guidelines for the management of patients with valvular heart disease recommend an international normalized ratio (INR) of 2.5 (range, 2-3) in patients with a mechanical valve at the aortic position. However, based on the results of the Prospective Randomized On-X Anticoagulation Clinical Trial (PROACT), the Food and Drug Administration approved this valve in April 2015 in the aortic position with a lower INR goal of 1.5-2.0. This reduction in INR goals led to a statistically significant reduction in the combined endpoint of clots, bleeding events, and stroke rates with 9/patient-years for the lower INR group compared with 12/patient-years in the standard INR group. This review compares the currently available literature on the On-X valve with that of other contemporary valves.
Chaudhary et al. (Fri,) conducted a review in Valvular heart disease with a mechanical valve at the aortic position. On-X valve with lower INR goal (1.5-2.0) vs. Standard INR goal (2.5) was evaluated on Combined endpoint of clots, bleeding events, and stroke rates. A lower INR goal of 1.5-2.0 for the On-X valve in the aortic position significantly reduced clots, bleeding, and stroke compared to standard INR (9 vs 12 per patient-years).