Application of electrical energy to the heart is effective in treating many dysrhythmias. There are, however, also disadvantages associated with cardioversion. Employment of external electrical current has been shown to induce epicardial and myocardial damage at the site of electrode application. We present the only case in the English literature of vocal fold paralysis in which the single identified associated event was cardioversion. In this case of temporary vocal fold paralysis, there was no invasive procedure to directly damage the nerve. Echocardiography of the patient revealed a large left atrium, placing the recurrent laryngeal nerve in an abnormal anatomic position where it was vulnerable to the electric current.