Objectives: The aim of this prospective study was to assess the risks of electrical shock cardio-version in the treatment of supraventricular rhythm disorders when administered under effective-dose but short duration anticoagulation in patients with no intracavitary thrombus detectable by transesophageal echocardiography.
Patients and methods: One hundred nineteen patients, mean age 66 years, with permanent arrhythmia due to atrial fibrillation (n = 102), atrial flutter (n = 16) or atrial tachycardia (n = 1) and taking no long-term anticoagulant therapy were treated by electrical shock cardioversion. The patients were given heparin at an effective dose 72 hours prior to cardioversion. A transthoracic and a transesophageal echocardiography were performed less than 24 hours prior to cardioversion.
Results: Twenty-one thrombi were evidenced in 16 patients (14.6%) including 18 in the left auricle, 1 in the left atrium and 2 in the right atrium. A spontaneous contrast was visualized in 38 patients (32%). Cardioversion was performed in 103 patients without thrombus and later in 9 of the 16 patients with thrombus after absorption under anticoagulant therapy as evidenced on the control transesophageal echocardiography. A sinus rhythm was obtained in 82% of the cases. All patients were given anti-vitamin K anticoagulants for one month. There were no clinical manifestation of ischemic vascular events during cardioversion nor during the one-month follow-up.
Conclusion: Early use of electrical shock cardioversion in patients with supraventricular rhythm disorders can be proposed without long-term anticoagulation therapy if the absence of thrombi is demonstrated by transesophageal echocardiography and short-term heparin is given followed by oral anticoagulants for at least 4 weeks. A large-scale randomized prospective study comparing the conventional strategy with the protocol used in this study would be required to definitively validate this approach and determine its possible advantages.