Prophylactic doses of low-molecular weight heparin as periprocedural bridging therapy in mechanical heart valve patients

Mechanical heart valve (MHV) patients undergoing invasive procedures necessitating an interruption of their lifelong anticoagulant therapy, often require bridging with low-molecular weight heparin (LMWH) or unfractionated heparin. The aim of this study was to assess whether bridging MHV patients with prophylactic doses of LMWH undergoing invasive, elective procedures is a safe and effective method.

This observational cohort study included all MHV patients on vitamin K anticoagulant therapy in Malmö, registered and monitored via AuriculA (the Swedish national quality registry for atrial fibrillation and anticoagulation), between 1/1/2008 and 31/12/2011. Inclusion criteria were periprocedural bridging therapies conducted via AuriculA. Primary endpoints were mortality, thromboembolic (TE) events or major bleedings (MBE) within 30 days of bridging.

During the study period, 210 patients had undergone 434 bridging therapies managed via AuriculA; 203 due to subtherapeutic INR-values were excluded. The remaining 231 periprocedural bridging therapies were included. All were bridged with prophylactic doses of LMWH. When comparing patients with aortic and/or mitral valve replacements undergoing low- or high-risk interventions, only number of days bridged for a low-risk intervention differed significantly. Patients with a mitral or mitral and aortic valve replacement were bridged for a longer period (p=0.023). No TE events, 1 death (0.4%) and 3 MBEs (1.3%) occurred related to periprocedural bridging.

Our study shows a low rate of MBEs, deaths and no TE events when bridging MHV patients undergoing invasive, elective procedures with prophylactic doses of LMWH.