ADD-ONS / MEDICATION

Perioperative and Periprocedural Management of the Anticoagulant Therapy

Created 09/02/2022, last revision 05/11/2023

2017 – ACC Expert Consensus Decision Pathway for Periprocedural Management of Anticoagulation in Patients With Nonvalvular Atrial Fibrillation

long-term anticoagulation therapy often has to be interrupted for various reasons (most often due to planned diagnostic or surgical procedures); for the interruption in emergencies, see the chapter on neutralizing the anticoagulant effect
the decision to discontinue anticoagulation periprocedurally represents a complex balancing act between the estimated risk of thromboembolism and bleeding
4 questions need to be addressed:
- is it necessary to discontinue anticoagulation?
- if so, how long before the procedure should it be discontinued?
- is bridging therapy necessary? at what dose?
- when should the anticoagulant therapy be restarted after the procedure?
to answer these questions, we need to evaluate:
- individual risk of thromboembolism
- the risk of bleeding (taking into account the characteristics of the patient and the planned procedure)
  - type of procedure and its risk of bleeding
  - features of the prescribed anticoagulant agent (warfarin x DOAC)
  - renal functions

warfarin requires a rather complex procedure – timely discontinuation (at least 3-5 days before the procedure), then monitoring of INR decline and starting LMWH once INR gets below 2 (if bridging is indicated)
DOACs simplify the situation because of their rapid onset of action and predictable, relatively short-lasting normalization of coagulation parameters (LMWH bridging is therefore not necessary in most cases)

Is it really necessary to stop anticoagulant therapy?

it is always a matter of better or worse estimate because the ratio of the thromboembolism risk (TE) when anticoagulation is withdrawn and bleeding when it is retained is often unclear
- TE is relatively rare but can be fatal
- bleeding with continued anticoagulation is more common but often less clinically relevant, usually without permanent sequelae

Thromboembolism risk assessment

use the CHA₂DS₂-VASc score in patients with Afib
in patients with venous thrombosis (VTE), the time since the diagnosis of VTE and the presence/absence of thrombophilia (a prothrombotic state) are taken into account
in patients with a mechanical valve, the risk depends on the type and location of the valve and the presence of contributing risk factors (AFib, heart failure, hypertension, diabetes, age >75y, previous stroke)

	Clinical Indication for Anticoagulant Therapy
Thromboembolic Risk Category	Atrial Fibrillation	Mechanical Heart Valve	VTE
High risk (annual risk >10%)	CHADS₂ score 5-6 recent (< 3 months) stroke/TIA rheumatic valvular heart disease	any mechanical mitral valve older aortic mechanical valve (caged ball, tilting disk) recent (< 3 months) stroke or TIA	recent (< 3 months) VTE high-risk thrombophilia (deficiency of protein C, protein S, or antithrombin; antiphospholipid syndrome; homozygous factor V Leiden or prothrombin gene mutation)
Moderate risk (annual risk 5% to 10%)	CHADS₂ score 3-4	bileaflet aortic valve prosthesis with ≥1 risk factor	VTE within 3–12 months moderate-risk thrombophilia (heterozygous factor V Leiden or prothrombin gene mutation) recurrent VTE active cancer (metastatic or treated within the past 6 months)
Low risk (annual risk <5%)	CHADS₂ score 0–2 (no prior stroke or TIA)	bileaflet aortic valve prosthesis without any risk factors	VTE >12 months ago

Bleeding risk assessment

consider a combination of individual patient risks and the risk of the procedure itself
take into account the localization and invasiveness of the procedure
many procedures can be safely performed without interrupting anticoagulation (either warfarin or DOACs) – dermatological, ophthalmological, and dental procedures

CHA2DS2-VASc score

→ see here

ABC score

in addition to clinical factors, the ABC-bleeding risk score also incorporates the biomarkers: high-sensitivity troponin T, growth differentiation factor–15, and hemoglobin

→ ABC-bleeding score online calculator

→ more about the ABC score here

ABC-stroke score

ABC-bleeding score

HAS-BLED score

→ HAS-BLED score calculator

a tool to guide the decision to initiate anticoagulation in patients with Afib
always compare the risk for major bleeding (calculated by the HAS-BLED score) with the risk of thromboembolic events (calculated by the CHA₂DS₂-VASc score) ⇒ does the benefit of anticoagulation outweigh the risk of bleeding?
a study comparing HEMORR2HAGES, ATRIA, and HAS-BLED showed superior performance of the HAS-BLED score compared to the other two scores

HAS-BLED score
Hypertension	uncontrolled BP (SBP >160 mmHg)	1
Abnormal liver/renal function	renal disease – dialysis, transplant, Cr >2.26 mg/dL or >200 µmol/L liver disease – cirrhosis or bilirubin >2x normal or AST/ALT/AP >3x normal	1 1
Stroke	previous stroke	1
Bleeding	prior major bleeding or predisposition to bleeding	1
Labile INR	unstable INR, time in therapeutic range <60%	1
Elderly	age ≥ 65 years	1
Drugs/alcohol	medication predisposing to bleeding – aspirin, clopidogrel, NSAIDs heavy alcohol use	1 1

HAS-BLED score	Pisters et al. annual ICH risk	Lip et al. annual ICH risk
0	1.1%	0.9%
1	1%	3.4%
2	1.9%	4.1%
3	3.7%	5.8%
4	8.7%	8.9%
5	12.5%	9.1 %
Not enough data for higher scores; risk is most likely > 10%

A score ≥ 3 is associated with an increased risk of major bleeding.
Frequent monitoring, DOAC use, or alternatives to anticoagulation (such as LAA occlusion) are recommended.

ORBIT score

The ORBIT bleeding risk score has a superior predictive ability for major bleeding in AFib patients compared to the HAS-BLED and ATRIA risk scores. The ORBIT risk score may provide a simple, easy-to-remember tool to assist in clinical decision-making [O´Brian, 2015] [Hilkens, 2017]

→ ORBIT online calculator

Older age ( >75 y)	1
Reduced hemoglobin/Hct/anemia (men <13 g/dL and Hct < 40%, women < 12 g/dL and Hct < 36% )	2
Bleeding	2
Insufficient kidney function (GFR < 60 mL/min/1.73 m²)	1
Treatment with antiplatelets	1

Maximum score	7
score 0–2 – low risk ~ 2.4% / y score 3 – medium risk ~ 4.7% / y score ≥ 4 – high risk ~ 8.1% / y

The risk of bleeding is unlikely to be increased	simple dental procedures
The risk of bleeding is probably not increased	cataract surgery dermatological procedures TRUS (ultrasound-guided prostate biopsy) spinal and epidural punctures carpal tunnel surgery
The risk of bleeding is apparently not increased	EMG transbronchial biopsy colonoscopic polypectomy endoscopic gastric biopsy ultrasound-guided biopsies sphincterotomy
The risk of bleeding is possibly increased
The risk of bleeding is probably increased	total endoprosthesis (TEP)

Timing of anticoagulant therapy discontinuation

Warfarin

discontinue warfarin 3-5 days before the procedure
monitor INR

DOAC

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Discontinuation of DOAC before neuraxial anesthesia

higher perioperative hemorrhagic risk is assumed; therefore, a longer interval is recommended
- for dabigatran 4-5 days before surgery
- for Xa inhibitors 3-5 days before surgery
restart DOAC ≥ 24 hours after the procedure
consider LMWH bridging in high-risk patients
separate guidelines for spinal and analgesic procedures are here and here

Is bridging required?

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Restart of the anticoagulant therapy

restart timing is sometimes a neglected issue, although it is an important factor influencing the outcome
it is usually not necessary to start full anticoagulation (heparin, LMWH, DOAC) within 6-12 hours after the procedure
according to the BRIDGE trial, it is not recommended to start full anticoagulant therapy within 24-72 hours after the procedure
- in patients at high risk of bleeding, wait for 72 h (especially for DOACs or LMWH, where the onset of anticoagulant effect is rapid)
- warfarin may be given earlier due to the delayed onset of full action