Related Experiment Video
Updated: Mar 21, 2026
Full-root Aortic Valve Replacement by Stentless Aortic Xenografts in Patients with Small Aortic Roots
Published on: May 21, 2017
Safety and Use of Anticoagulation After Aortic Valve Replacement With Bioprostheses: A Meta-Analysis
Haris Riaz1, Shehab Ahmad Redha Alansari2, Muhammad Shahzeb Khan2
1From the Department of Internal Medicine, Cleveland Clinic, OH (H.R., S.A.R.A.); Department of Cardiothoracic Surgery, Heart and Vascular Institute, Cleveland Clinic, OH (S.A.R.A., S.R.); Department of Internal Medicine, Dow University of Health Sciences, Karachi, Pakistan (M.S.K.); Department of Internal Medicine, Bronx Lebanon Hospital, New York, NY (T.R.); Department of Cardiovascular Medicine, Mercy Saint Vincent Medical Center, Toledo, OH (F.K.L.); Department of Cardiovascular Medicine, University of Louisville, KY (A.R.K.); Department of Internal Medicine, University of Arizona, Tucson (I.B.R.); and Department of Cardiovascular Medicine, Duke University, Durham, NC (R.A.K.). riazh@ccf.org.
Insights
Anticoagulation after aortic bioprosthesis replacement increases bleeding risk without improving outcomes, challenging current guidelines. Further research is needed to refine treatment strategies for these patients.
Area of Science:
- Cardiology
- Cardiovascular Surgery
- Pharmacology
Background:
- Current American College of Cardiology guidelines recommend 3 months of anticoagulation for patients with bioprosthetic aortic valves.
- Clinical practice varies, and study results conflict regarding the optimal duration of anticoagulation.
- Evidence is pooled to inform clinical decision-making on anticoagulation risks and benefits.
Purpose of the Study:
- To assess the association between anticoagulation and outcomes after aortic bioprosthesis replacement.
- To evaluate the risk of bleeding versus the benefit of preventing thromboembolic events.
- To provide evidence-based recommendations for clinical practice.
Main Methods:
- A systematic literature search was conducted on PubMed up to April 2015.
- Included studies compared warfarin with aspirin or no antiplatelet/anticoagulant therapy.
- Meta-analysis using random effects model assessed outcomes including thromboembolism and bleeding events.
Main Results:
- Warfarin use significantly increased bleeding risk (OR 1.96) compared to aspirin or placebo.
- No significant difference in thromboembolic events (stroke, TIA) at 3 months (OR 1.13) or beyond (OR 1.12).
- Pooled data from 13 studies (8251 patients) informed these findings.
Conclusions:
- Anticoagulation with warfarin increases bleeding risk post-aortic bioprosthesis without reducing thromboembolic events.
- Findings contradict current guidelines, suggesting a need for reassessment.
- Larger randomized controlled trials are recommended to guide clinical practice.
Background:
The American College of Cardiology guidelines recommend 3 months of anticoagulation after replacement of the aortic valve with a bioprosthesis. However, there remains great variability in the current clinical practice and conflicting results from clinical studies. To assist clinical decision making, we pooled the existing evidence to assess whether anticoagulation in the setting of a new bioprosthesis was associated with improved outcomes or greater risk of bleeding.
Methods And Results:
We searched the PubMed database from the inception of these databases until April 2015 to identify original studies (observational studies or clinical trials) that assessed anticoagulation with warfarin in comparison with either aspirin or no antiplatelet or anticoagulant therapy. We included the studies if their outcomes included thromboembolism or stroke/transient ischemic attacks and bleeding events. Quality assessment was performed in accordance with the Newland Ottawa Scale, and random effects analysis was used to pool the data from the available studies. I(2) testing was done to assess the heterogeneity of the included studies. After screening through 170 articles, a total of 13 studies (cases=6431; controls=18210) were included in the final analyses. The use of warfarin was associated with a significantly increased risk of overall bleeding (odds ratio, 1.96; 95% confidence interval, 1.25-3.08; P<0.0001) or bleeding risk at 3 months (odds ratio, 1.92; 95% confidence interval, 1.10-3.34; P<0.0001) compared with aspirin or placebo. With regard to composite primary outcome variables (risk of venous thromboembolism, stroke, or transient ischemic attack) at 3 months, no significant difference was seen with warfarin (odds ratio, 1.13; 95% confidence interval, 0.82-1.56; P=0.67). Moreover, anticoagulation was also not shown to improve outcomes at time interval >3 months (odds ratio, 1.12; 95% confidence interval, 0.80-1.58; P=0.79).
Conclusions:
Contrary to the current guidelines, a meta-analysis of previous studies suggests that anticoagulation in the setting of an aortic bioprosthesis significantly increases bleeding risk without a favorable effect on thromboembolic events. Larger, randomized controlled studies should be performed to further guide this clinical practice.
Related Concept Videos
01:22Aneurysm IV: Nursing Management
01:25Aortic Regurgitation III: Medical Management
01:29Venous Thrombosis III: Interprofessional Care
01:26Aneurysm III: Interprofessional Care
01:18Anticoagulant Drugs: Vitamin K Antagonists and Direct Oral Anticoagulants
Warfarin, a prominent vitamin K antagonist family member, exerts its effect by inhibiting the enzyme VKORC1 (vitamin K epoxide reductase complex 1). By hindering this enzyme, warfarin...
01:30Anticoagulant Drugs: Low-Molecular-Weight Heparins