Antithrombotic Strategy in the Three First Months following Bioprosthetic Heart Valve Implantation

Abstract

Heart valve prosthesis unquestionably improve quality of life and survival of patients with severe valvular heart disease, but the need for antithrombotic therapy to prevent thromboembolic complications is a major challenge to clinicians and their patients. Of the articles analyzed, most were retrospective series of cases or historical cohorts obtained from the database. The few published randomized trials showed no statistical power to assess the primary outcome of death or thromboembolic event. In this article, we decided to perform a systematic literature review, in an attempt to answer the following question: what is the best antithrombotic strategy in the first three months after bioprosthetic heart valve implantation (mitral and aortic)?After two reviewers applying the extraction criteria, we found 1968 references, selecting 31 references (excluding papers truncated, which combined bioprosthesis with mechanical prosthesis, or without follow-up).Based on this literature review, there was a low level of evidence for any antithrombotic therapeutic strategy evaluated. It´s therefore interesting to use aspirin 75 to 100 mg / day as antithrombotic strategy after bioprosthesis replacement in the aortic position, regardless of etiology, for patients without other risk factors such as atrial fibrillation or previous thromboembolic event. In the mitral position, the risk of embolism, although low, is more relevant than in the aortic position, according to published series and retrospective cohorts comprised mostly of elderly non-rheumatic patients.The current evidence is limited to have a consistent and safe level of evidence regarding the best therapeutic strategy. Based on these studies, 75 to 100 mg/day of aspirin is interesting as antithrombotic strategy after implantation of aortic bioprosthesis, regardless of etiology, for patients with no other risk factors such as atrial fibrillation or previous thromboembolic event. As for mitral bioprosthesis, the risk of embolism, although low, is more relevant than in the aortic position, according to published series and retrospective cohorts - usually elderly non rheumatic patients.

Dabigatran Versus Warfarin After Bioprosthesis Valve Replacement for the Management of Atrial Fibrillation Postoperatively: DAWA Pilot Study

“…The bioprosthesis emerged last century with the expectation of replacing existing mechanical prosthesis, due to not theoretically requiring permanent oral anticoagulation. Actually, the recommendations of the main international guidelines on antithrombotic therapy after bioprosthesis implantation demonstrate a low level of evidence (Grade C), which may be explained by the lack of randomized trials in this scenario [ 13 ].…”

“…Besides, stroke, death and major bleeding occurred only in the first group. All patients in our study have more than a 3-month interval from surgery for recruitment, a period known to have a lower incidence of embolic events [ 20 ].…”

Follow-up and management of valvular heart disease patients with prosthetic valve: a clinical practice guideline for Indian scenario

“…The optimal antithrombotic regimen and its duration after placement of a bioprosthetic device are less clear. Studies have demonstrated that bioprosthetic devices have an increased risk for thromboembolic events during the first three months after the procedure which is less than that associated with mechanical valves [54,55].…”