BRIO VAD Anticoagulation Initiation
For BRIO ventricular assist device implantation, initiate warfarin anticoagulation targeting INR 2.0-3.0 combined with aspirin 81-325 mg daily, starting within 24-48 hours postoperatively once surgical hemostasis is confirmed and chest tube drainage is minimal. 1
Immediate Postoperative Period (First 24-48 Hours)
Hold all anticoagulation immediately postoperatively until surgical bleeding is controlled, typically when chest tube output is <50 mL/hour and hemodynamic stability is achieved. 1, 2
Begin aspirin 81-325 mg daily as soon as oral intake is tolerated, usually within 12-24 hours post-implantation, as antiplatelet therapy is necessary due to shear-induced platelet dysfunction and thrombosis risk with continuous-flow devices. 1
Initiate warfarin within 24-48 hours after confirming adequate hemostasis, starting with standard loading doses (typically 5-10 mg depending on patient factors). 1
Bridging Anticoagulation Strategy
Use unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) as bridging therapy starting 24-48 hours postoperatively until therapeutic INR is achieved, as the necessity of bridging is patient-specific and should be guided by the implanting center. 1
Target activated partial thromboplastin time (aPTT) of 50-70 seconds if using UFH, or use weight-based LMWH dosing (typically enoxaparin 1 mg/kg subcutaneously twice daily). 1, 2
Discontinue bridging anticoagulation once INR reaches 2.0 on two consecutive measurements at least 24 hours apart. 1
Target Anticoagulation Parameters
Maintain INR between 2.0-3.0 for all continuous-flow devices, though the exact target may vary by center, practice, and specific device type. 1
Add a second antiplatelet agent (clopidogrel 75 mg daily) in many centers, as upregulation of platelet function with mechanical circulatory support contributes to long-term thromboembolic risk. 1
Monitor INR at least twice weekly during the initial titration phase until stable therapeutic levels are achieved for at least two consecutive weeks. 1
Critical Monitoring Requirements
Check complete blood count daily during the first week to detect thrombocytopenia or anemia, as bleeding episodes remain a serious complication of VAD support. 2, 3
Assess for acquired von Willebrand disease if non-surgical bleeding occurs despite appropriate INR, as loss of large von Willebrand factor multimers occurs in all continuous-flow VAD patients and cannot be explained by anticoagulation regimen alone. 3
Maintain mean arterial pressure 70-90 mmHg through aggressive blood pressure management, as hypertension increases afterload, decreases pump flow, and increases risk of neurological events. 1
Special Circumstances Requiring Modified Approach
Heparin-Induced Thrombocytopenia (HIT)
Use bivalirudin or danaparoid-sodium as alternative anticoagulants if HIT type II is diagnosed, though these agents carry serious bleeding and thromboembolic risks. 4, 5
Consider using heparin intraoperatively only in selected HIT-positive cases with negative heparin-induced platelet aggregation testing at time of implantation, then immediately transition to alternative agents postoperatively. 5
Subtherapeutic INR Management
Resume bridging with UFH or LMWH in outpatient setting until therapeutic INR is re-established, as the necessity of bridging is patient-specific. 1
Do not use direct oral anticoagulants (DOACs) including dabigatran, rivaroxaban, or apixaban, as these are contraindicated for any prosthetic valve or mechanical circulatory support device due to excessive thrombotic complications. 1, 6
Common Pitfalls to Avoid
Never delay warfarin initiation beyond 48 hours unless active bleeding persists, as thromboembolic risk begins immediately after device activation. 1, 2
Never use DOACs instead of warfarin for VAD patients, as dabigatran treatment causes harm compared to warfarin in mechanical assist device patients. 1
Never target INR below 2.0 even in patients at high bleeding risk, as subtherapeutic anticoagulation dramatically increases pump thrombosis risk. 1
Never discontinue aspirin even if bleeding complications occur, as antiplatelet therapy is mandatory due to stasis, thrombosis, and shear-induced platelet dysfunction inherent to continuous-flow devices. 1
Long-Term Anticoagulation Maintenance
Continue warfarin (INR 2.0-3.0) plus aspirin indefinitely for the duration of VAD support, as this represents the standard antithrombotic regimen to minimize pump thrombosis and prevent ischemic stroke. 1
Monitor INR weekly to monthly once stable therapeutic levels are consistently achieved, with more frequent monitoring during intercurrent illness or medication changes. 1
Adjust warfarin dosing promptly for any INR outside the 2.0-3.0 range, as both subtherapeutic and supratherapeutic levels significantly increase morbidity and mortality. 1