ICD (implantable cardioverter-defibrillator) has been recently accepted as the most effective treatment for patients with medically refractory or life threatening ventricular tachycardia or ventricular fibrillation. Determination of the DFT (defibrillation threshold) is important in the implantation of ICD. DFT is the lowest shock energy that successfully terminates ventricular fibrillation. Preoperative amiodarone use, increased body size, and left ventricular dilatation are associated with high DFT. Recently, we experienced a 66 year-old male patient presenting with syncope due to idiopathic ventricular fibrillation in whom DFT was high and unstable, probably due to preoperative use of amiodarone.
Aged ; Amiodarone ; Body Size ; Dilatation ; Humans ; Male ; Shock ; Syncope ; Tachycardia, Ventricular ; Ventricular Fibrillation*

Malignant melanoma develops from the melanocyte and the most common primary site is skin, followed by mucosa and retina. Even though any other tissue where melanocytes reside could be the primary site of the malignant melanoma, the one developed in the mediastinum is rarely reported. We experienced a patients of 54 years old woman whose initial symptom was progressive dyspnea for one month, and proved to have the anterior mediastinal mass with pleural effusion and the small mass in the abdominal soft tissue. The needle aspiration biopsy from the mediastinal mass showed the consistent findings with malignant melanoma. We concluded the mediastinum was the primary site of the malignant melanoma of this patient because we couldn't find any other evidence of primary tumor in skin, oral and gastrointestinal mucosa, and retina. She has been treated with combined chemotherapy with dacarbazine, cisplatin and vinblastine. Her symptom was improved after chemotherapy and follow up chest CT after three cycles of chemotherapy showed the decreased tumor size in the mediastinum.
Biopsy, Needle ; Cisplatin ; Dacarbazine ; Drug Therapy ; Dyspnea ; Female ; Follow-Up Studies ; Humans ; Mediastinum* ; Melanocytes ; Melanoma* ; Middle Aged ; Mucous Membrane ; Needles ; Pleural Effusion ; Retina ; Skin ; Tomography, X-Ray Computed ; Vinblastine