Should all patients with dilated cardiomyopathy receive chronic anticoagulation?
JW Cheng
and
SA Spinler
OBJECTIVE: To review the mechanism of intracardiac thrombus formation, describe the risk of systemic thromboembolization, critically evaluate the literature regarding the use of oral anticoagulation, review the American College of Chest Physicians (ACCP) guidelines, and provide recommendations for oral anticoagulation in patients with dilated cardiomyopathy (DCM). DATA SOURCES: English language clinical studies, abstracts, and review articles pertaining to oral anticoagulation and DCM. STUDY SELECTION AND DATA EXTRACTION: Relevant human studies examining the role of anticoagulation for preventing systemic thromboembolism in patients with DCM. DATA SYNTHESIS: Potential mechanisms and risk factors for systemic thromboembolization in patients with DCM are discussed. Studies evaluating the benefits and risks of chronic oral anticoagulation to prevent systemic thromboembolization are critiqued. Recommendations for oral anticoagulation in patients with DCM from the second and third ACCP Consensus Conferences are reviewed. Suggestions for study design of a new clinical trial are presented. CONCLUSIONS: The second ACCP Consensus Conference recommended chronic anticoagulation for all patients with DCM, but the third conference did not address this issue. Review of demographic data from clinical trials demonstrates reluctance to use anticoagulation in all patients with DCM because of lack of support from prospective, controlled trials. Recent data from large clinical trials suggest that the risk of systemic embolization may be lower than previously believed. We recommend the use of chronic anticoagulation with warfarin in patients for whom the risk of embolism is greater than the risk of major bleeding, such as those with atrial fibrillation or previous systemic embolization. Lack of compliance with ACCP guidelines suggests that clinicians require additional information regarding the bleeding risk and systemic embolization rate reduction of chronic anticoagulation in patients with DCM who remain in normal sinus rhythm. It is only through prospective, controlled trials that this risk/benefit ratio to prevent systemic embolism in patients with DCM can be established.
