What is the treatment for Acitrom (Acenocoumarol) toxicity with elevated INR and gum bleeding after MVR and AVR?

Management of Acitrom (Acenocoumarol) Toxicity with INR >7 and Gum Bleeding Post-MVR+AVR

For a patient with mechanical MVR+AVR presenting with INR >7 and active gum bleeding, immediately hold acenocoumarol and administer low-dose oral vitamin K (1-2 mg) to reverse the coagulopathy while avoiding overcorrection that could precipitate valve thrombosis. 1

Immediate Management Algorithm

Step 1: Stop Anticoagulation and Assess Bleeding Severity

• Immediately discontinue acenocoumarol 1
• Assess if bleeding is minor (gum bleeding only) versus life-threatening (intracranial, massive GI, hemodynamic instability) 1
• For minor bleeding with INR >7: This represents significant over-anticoagulation requiring reversal but not emergency measures 2

Step 2: Vitamin K Administration Strategy

For INR >7 with minor bleeding (gum bleeding):

• Administer oral vitamin K₁ (phytomenadione) 2.5-5 mg orally 1, 2
• Oral route is strongly preferred over IV to avoid anaphylactoid reactions 1, 2
• This dose will reduce INR from >7 to 2.0-5.0 range within 24-48 hours 2
• Avoid high-dose vitamin K (>5 mg) as it creates prolonged resistance to warfarin and potential hypercoagulable state, which is particularly dangerous in patients with both mechanical MVR and AVR 1

Critical caveat: Acenocoumarol responds less effectively to vitamin K reversal compared to warfarin, so expect slower INR correction 2

Step 3: Emergency Reversal (If Needed)

Only if life-threatening bleeding develops:

• Administer fresh frozen plasma (FFP) or intravenous prothrombin complex concentrate (PCC) for immediate reversal 1
• Add low-dose vitamin K (1-2 mg oral) because FFP/PCC have shorter half-lives than acenocoumarol's anticoagulant effect 1
• Do NOT use recombinant Factor VIIa - this is contraindicated in mechanical valve patients due to thrombosis risk 3

Monitoring and Follow-Up

INR Monitoring Schedule

• Check INR at 24 hours post-vitamin K administration 2
• Continue daily INR monitoring until stable in therapeutic range 1
• For this patient with MVR+AVR, target INR should be 2.5-3.5 once restarted 4, 5

When to Restart Acenocoumarol

• Resume acenocoumarol when INR falls to <3.0 and bleeding has completely stopped (typically 12-24 hours after bleeding cessation) 1
• Start at reduced dose (approximately 50-75% of previous maintenance dose) 2
• This patient requires lifelong anticoagulation due to dual mechanical valves, so prompt but safe reinitiation is essential 1

Risk Stratification for This Patient

High Thrombotic Risk Factors Present

This patient has extremely high thrombotic risk due to:

• Mechanical MVR (highest risk valve position) 1
• Combined MVR+AVR (multiple mechanical valves) 1
• Any interruption of anticoagulation carries substantial stroke/valve thrombosis risk 4, 5

Bleeding Risk Assessment

• INR >7 increases bleeding risk dramatically, though absolute risk remains <5.5 per 1000 per day 2
• Gum bleeding represents minor hemorrhage that is easily controlled 1
• The thrombotic risk from overcorrection equals or exceeds the bleeding risk at this INR level 2

Target INR Range for Long-Term Management

For mechanical MVR+AVR (double valve replacement):

• Target INR: 2.5-3.5 4
• Asian populations may tolerate slightly lower ranges (2.0-2.5 for MVR) with acceptable thrombotic outcomes, but this patient has dual valves requiring higher targets 5
• Weekly INR monitoring once stable 6

Common Pitfalls to Avoid

1. Never use high-dose vitamin K (>5 mg) - causes warfarin resistance lasting weeks and creates prothrombotic state dangerous for mechanical valve patients 1

2. Never use direct oral anticoagulants (DOACs) - absolutely contraindicated in mechanical valve patients due to increased thrombosis and bleeding 1

3. Do not delay vitamin K administration - waiting for "spontaneous" INR correction with acenocoumarol holding alone takes too long and maintains bleeding risk 2

4. Avoid subcutaneous vitamin K - causes cutaneous reactions and has unpredictable absorption; oral route is superior 2

5. Do not over-correct INR to <2.0 - this patient's thrombotic risk with dual mechanical valves is catastrophic if under-anticoagulated 4, 5

Identifying the Cause of INR Elevation

Investigate these common causes:

• Infectious processes (34% of INR derangements in mechanical valve patients) 4
• Poor medication compliance (15% of patients show poor compliance) 4
• Drug interactions - particularly antibiotics like amoxicillin which can dramatically increase acenocoumarol effect 7
• Dietary changes affecting vitamin K intake 2

Patient education is critical: 85% compliance rate is achievable with proper counseling about daily anticoagulation importance 4