Lower anticoagulation for mechanical heart valves: Experience with the ATS bileaflet valve

Major Hemorrhagic and Thromboembolic Complications in Patients with Mechanical Heart Valves Receiving Oral Anticoagulant Therapy

“…The number of clinical studies that assessed bleeding and thromboembolic complication rates in patients with a mechanical heart valve prosthesis is limited [VA 1985;Cortelazzo 1993;Horskotte 1993aHorskotte , 1993bCannegieter 1995;Acar 1996;Aris 1996;Fiore 1998;Massel 2001;Butchart 2002;Ansell 2004;Levine 2004]. The intensity of the target anticoagulation level is different for many of these studies, and the defi nitions of major hemorrhagic and thromboembolic complications are inconsistent [VA 1985;Saour 1990;Cortelazzo 1993;Horskotte 1993aHorskotte , 1993bTurpie 1993;Acar 1996;Altman 1996;Aris 1996;Meschengieser 1997;Pengo 1997;Fiore 1998;Massel 2001;Butchart 2002;Van Nooten 2003;Ansell 2004;Levine 2004]. The reader must be aware of these discrepancies when interpreting the results from these clinical studies.…”

Anticoagulation or antiplatelet therapy of bioprosthetic heart valves recipients: an unresolved issue

“…To diminish the risk of bleeding that can occur at these levels of anticoagulation, successful attempts have been made, in various populations, to lower the target INR, with a highly significant decrease in the incidence of hemorrhagic complications, at the cost of only a slight increase in the incidence of thromboembolic events [23][24][25][26][27]. The therapeutic window of anticoagulation is, nevertheless, narrow and, according to the results of the GELIA study, the most important issue is stability of the INR within the target range [23,24], a goal which mandates frequent measurements and appropriate adjustments.…”

Improving the quality of anticoagulant therapy in patients with mechanical heart valves: what are we waiting for?

“…Reduced thrombogenicity of modern bileaflet valves is demonstrated by the low thromboembolic event rate in a recent trial with low-range anticoagulation 6 (INR 1.5-2.5) and in a poorly anticoagulated population. 7 The event rate fell in the range of the objective performance criteria required by the Food and Drug Administration.…”