INTENSITY OF THERAPY WITH ORAL ANTICOAGULANTS IN HEART-VALVE REPLACEMENT

In recent years randomized clinical trials using standardized prothrom bin time (international normalized ratio, INR) for the control of oral anticoagulant therapy have demonstrated that the use of a less intens e therapeutic range decreases the rate of bleeding without reducing an tithrombotic efficacy. Based on these results, the following guideline s for therapeutic ranges in heart valve replacement can be presently r ecommended: INR of 2.0 - 3.0 in patients with bioprosthetic valves for the first 3 months - except, probably, for patients with tissue valve s in aortic position who are in sinus rhythmus; long-term anticoagulat ion corresponding to an INR of 2.0 - 3.0 in all patients with bioprost hetic valves and either atrial fibrillation or postoperative arterial embolism or a left atrial thrombus at surgery; longterm treatment equi valent to an INR of 2.5 - 3.5 in all patients with mechanical prosthet ic heart valves.