Abstract: Objective To evaluate the clinical effect of implanted cardioverter-defibrillators (ICD) for primary prevention of
sudden cardiac death. Methods According to ACC/AHA Guideline of ICD implantation (2005), 35 patients successfully
received ICD/CRT-D implantation for primary prevention of sudden cardiac death in our hospital from January 2006 to
December 2009. All the patients were followed up for a mean of 2 years. Results During the follow up, 11 (31.43%) patients
experienced entricular arrhythmic episodes, for which 16 defibrillation therapies and 75 anti-tachycardia pacing (ATP)
therapies were delivered without mistaken shock or death. The incidence rate of NVM was 100%, that of PVT was 66.67%,
Brugada syndrome 50%, HCM 25% and DCM 16.67%. Of these episodes, the incidence of VF episodes among PVC patients
was 87.5% (14 beats), ventricular tachycardia PVC was 82.28% (65 times), 5 beats in NVM patients, 4 beats in HCM and
Brugada syndrome patients, and 1 beat in DCM patients. No ICD implantation-related complication was detected, and no
ventricular tachycardia induced syncope occurred in these cases. All patients showed improved quality of life after the
implantation. Conclusions ICD implantation can prevent malignant ventricular arrhythmia episodes, especially for PVT, NVM
and Brugada syndrome in high risk SCD patients, demonstrating the value of implantation of ICD as a primary prevention in
high-risk SCD patients.