Prevalence of atrial thrombi in patients with atrial fibrillation/flutter and subtherapeutic anticoagulation prior to cardioversion.

AIMS: Thromboembolism may complicate electrical cardioversion (ECV) of atrial fibrillation/flutter (AF). The use of 3 weeks of warfarin before ECV results in a substantial reduction of thromboembolic complications. Nevertheless, in patients scheduled for ECV subtherapeutic INR levels are common. We sought to assess the prevalence and the predictors of atrial thrombi in patients affected with sustained AF in whom subtherapeutic INR values were detected in the 3 weeks preceding scheduled ECV. METHODS AND RESULTS: Forty-one patients with persistent AF and > or =3 weeks warfarin anticoagulation who exhibited subtherapeutic INR values in the last 3 weeks underwent a transoesophageal echocardiogram (TOE) before a scheduled ECV. A left atrial appendage (LAA) thrombus was diagnosed on TOE in four patients (9.8%). Patients with thrombus had lower INR values (1.45+/-0.09 vs 1.72+/-0.20; p=0.0068), lower LAA emptying velocities (13.75+/-4.5 vs 25.86+/-12.4 cm/s; p=0.0313) and higher prevalence of atrial smoke (100 vs 37.8%,p=0.03). CONCLUSIONS: Subtherapeutic levels of anticoagulation before elective ECV of AF may expose patients to post-ECV thromboembolic sequelae, especially in patients with lowest INR values. Current recommendations of a full course of therapeutic anticoagulation before ECV of persistent AF should be firmly observed.

Efficacy and tolerability of a very low molecular weight heparin compared with standard heparin in patients with unstable angina: a pilot study.

BACKGROUND: Unstable angina is an active thrombotic process that involves thrombus formation and platelets. It requires a rapid and intensive treatment with anticoagulants and antiplatelets. HYPOTHESIS: The aim of the present study was to compare the efficacy of a very low molecular weight heparin, OP 2000, with standard heparin in the treatment of unstable angina. Tolerance and safety were also assessed. METHODS: The study population included 120 consecutive hospitalized patients with unstable angina randomized for treatment with very low molecular weight heparin or with standard heparin. The dosage of the study drug was 200 mg intramuscular (i.m.) the first day followed by 150 mg IM/day. The control drug was standard heparin starting at a dosage of 5,000 UI/ml intravenously (i.v.) and followed by continuous infusion at an activated partial thromboplastin time-adjusted dosage. The primary end points were death, acute myocardial infarction, urgent revascularization, and recurrence of angina. Tolerability was assessed using bleeding parameters, thrombocytopenia, and allergic reactions. RESULTS: Fourteen clinical events were reported in the study group compared with 25 events in the control group (p < 0.05). No adverse events were reported in either group. CONCLUSION: During the acute phase of unstable angina, treatment with a very low molecular weight heparin plus aspirin was more effective than treatment with standard heparin plus aspirin.