Anticoagulation for primary prophylaxis of thromboembolic events in patients with left ventricular dysfunction

Background: Patients with heart failure have an increased risk for thromboe mbolic events. In clinical practice the physician is often en confronted wi th the decision to establish a prophylactic anticoagulation. Data: The incidence for clinical embolization is 1.5 to 3.5% per ye;ir. It seems that patients with a lower peak oxygen uptake and with a lower ejecti on fraction are at higher risk for embolic events. There is no evidence for a correlation of such events with the clinical classification (NYHA) or wi th the genesis of heart failure. Concerning a prophylactic anticoagulation, the results of the published studies and meta-analyses are inhomogenous wi th a benefit in some, no difference in others and a significant disadvantag e for the patients with and coagulation in a part of them compared to a non -treated control group. None of these data is established by a prospective, randomized, controlled study with the primary endpoint thromboembolic even t in patients with or without anticoagulation. The incidence for a hemorrha ge under anticoagulation is 0.6-5.3% per year for life-threatening and 0.04 -0.64% for fatal bleeding. Conclusion:Because of similar incidences for thromboembolic events and for the bleeding complication of anticoagulation, there is no evidence for a ge neral indication for anticoagulation of patients with heart failure, persis tent sinus rhythm and lack of risk factors; In patients with high-grade hea rt failure (e.g. VO2max < 14 ml/min/kg body weight or left ventricular ejec tion fraction < 20-30%), who belong to a high-risk population, anticoagulat ion should be considered and may be acceptable in individual cases.