Effects of heparinoid bridging in patients with mechanical heart valves

Abstract

Background: Patients with mechanical heart valves (MHVs) require long-term oral anticoagulation therapy to protect against thromboembolisms. Invasive procedures with high bleeding risks require oral anticoagulation therapy cessation. Currently, guidelines recommend the use of either subcutaneous low-molecular-weight heparin or intravenous unfractionated heparin in the perioperative period. It is unclear whether the evidence supports the use of one heparinoid over the other. Objectives: To compare the effectiveness of low-molecular-weight heparin and unfractionated heparin bridging based on the adverse outcomes of thromboembolisms, major bleeding, and death during the perioperative period. Date sources: A literature search was conducted using PubMed, EMBASE, CINAHL, and the Cochrane Library. Five studies comparing the two bridging therapies in chronically anticoagulated MHV patients met the inclusion criteria. Conclusions: No statistical significance was found for the endpoints of thromboembolism and death. One study found a statistically significant higher occurrence of major bleeding in patients treated with unfractionated heparin. In all the studies, major bleeding occurred more often than thromboembolisms. Findings were limited by the study designs and methodologies. Implications for practice: Based on the available evidence, neither low-molecular-weight heparin nor intravenous heparin bridging was found to be more effective in reducing the occurrence of adverse events. This may be due in part to the study designs and lack of standardized bridging protocols used in the studies reviewed. Nurse practitioners should remain informed about bridging protocols and weigh the risk versus benefit of each bridging agent when caring for patients with MHVs.

Perioperative consultative hematology: can you clear my patient for a procedure?

“…Although observa tional data, this anal y sis sug gests that bleed ing risk asso ci ated with bridg ing in valve patients is not neg li gi ble and under scores the need for lim it ing to patients at increased throm botic risk. 42 Some obser va tional data sug gest that pro phy lac tic dose anticoagulation may be a via ble perioperative approach for select mechan i cal valve patients requir ing tem po rary inter ruption in war fa rin, as well as those with newly implanted valves as a bridge to a ther a peu tic INR of 2 or more. 43,44 This may mit i gate bleed ing risk but also pro vi des impor tant post op er a tive VTE pro phy laxis.…”