【Abstract】 Objective :Implantable cardioverter defibrillator (ICD) were implanted in two patients with drug refractory vertricular tachycardia ( VT) and ventricular fibrillation (VF)- Methods : Two patients were with organic heart disease (one case of old myocardialinfraction ,and the other of dilated cardiomyopathy) and had history of VTor VF- Antiarrhythmic drug therapy was unsuccessful- ICD was implanted in the chest pocket by nonthoracotomicalapproach- The pulse generator was connected with a single intravenous lead- Shocks were delivered through distal coilto the ICDshell- Results : Two patients had successful implantation using single lead ICDs- The defibrillation threshold was less than 15 J- No operative andperioperative complication occurred ,during follow up ,one patient had VFand was terminated by defibrillation , but 4 months afterimplantation the patient died due to necurrent VF;the other one after using of propaferone had recurrent VT with slow rate , which was not detected by the ICD,the VT window was reprogram med- Conclusion : Transvenous implantation of single lead ICDs is easy to perform and is an effective approach to treat ventricular arrhythmias-更多还原