Mechanical heart valve thrombosis and novel oral anticoagulants: a word of caution
Notice bibliographique
Résumé
not surprising that even vitamin K antagonists are prescribed to achieve different therapeutic levels in patients with AF versus mechanical heart valves, particularly in the mitral position. Therefore, the dosing of the new anticoagulants will likely have to be tailored to the indication for anticoagulation. There have only been a few preclinical models investigating the possible role of either dabigatran or rivaroxaban in mechanical valve thrombo-prophylaxis. McKellar and colleagues used an in vivo swine model whereby a modified bileaflet mechanical valved conduit (St Jude Masters Series, St Jude Medical, Inc., MN, USA) was implanted to bypass the ligated, native descending thoracic aorta to compare the amount of valve thrombosis at 30 days in a control group (no anticoagulation), a clinical group control (enoxaparin 2 mg/kg twice daily) and experimental group (dabigatran 20 mg/kg twice daily) [7]. Their short-term results demonstrated that dabigatran was as effective as enoxaparin in preventing modified heterotopic mechanical aortic valve thrombosis. There was no mortality difference between all groups. Conversely, Schomburg and colleagues used an orthotopic swine mechanical mitral valve replacement model (27 mm Carbomedics OptiFormTM Mitral Valve, Sorin, Vancouver, Canada), comparing control group (no anticoagulation), clinical control group (warfarin therapy) and experimental group (dabigatran therapy at 20 mg/kg twice daily) and demonstrated a significant survival benefit of the use of dabigatran when compared with warfarin therapy. However, thrombus presence at necropsy was found to be twice as high in the dabigatran group (80%) versus the warfarin group (40%; p = 0.2) [8]. Although in vitro studies demonstrated similar effectiveness of dabigatran or rivaroxaban to unfractionated heparin and low molecular weight heparin in Oral anticoagulant therapeutic options are currently expanding, not only in drug types, but their clinical indications. Dabigatran etexilate (Pradaxa) is a direct thrombin (IIa) inhibitor that has been approved for prevention of embolic stroke related to nonvalvular atrial fibrillation (AF) following results from the RE-LY trial, a study comparing dabigatran (110 or 150 mg twice daily) with warfarin in patients with nonvalvular AF, were published in 2009 [1,2]. RE-LY demonstrated similar rates of thromboembolic events in low-dose dabigatran versus warfarin, while higher doses of dabigatran showed even fewer thromboembolic events [2]. Along with other trials investigating new oral anticoagulants in patients with nonvalvular AF (RE-LY [2], ARISTOTLE [3], AVERROES [4], ROCKET-AF [5]), current national guidelines now have recommendations for the use of dabigatran, apixaban and rivaroxaban for prevention of stroke in nonvalvular AF patients and prevention of deep vein thrombosis following orthopedic surgery [1,6]; however, there is little information regarding the use of these medications in mechanical valve thromboprophylaxis. Thus, off-label use of these new drugs could lead to catastrophic complications, since their mechanism of anticoagulation does not mirror that of vitamin K antagonists.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».