A number of clinical trials have demonstrated the superiority of the<unk>  over AAD (antiarrhythmic drugs) in the prevention of death from malignant arrhythmias. The SCD-HeFT trial (published in 2005) showed a significant all-cause mortality benefit for patients with<unk> . Congestive heart failure patients that were implanted with an<unk>  had an all-cause death risk 23% lower than placebo and an absolute decrease in mortality of 7.2 percentage points after five years in the overall population.1 Reporting in 1999, the Antiarrhythmics Versus<unk>  Defibrillators (AVID) trial consisted of 1,016 patients, and deaths in those treated with AAD were more frequent (n = 122) compared with deaths in the<unk>  groups (n = 80, p < 0.001). In 2002 the MADITII trial showed benefit of<unk>  treatment in patients after myocardial infarction with reduced left ventricular function (EF<30). Initially<unk> s were implanted via thoracotomy with defibrillator patches applied to the epicardium or pericardium. The device was attached via subcutaneous and transvenous leads to the device contained in a subcutaneous abdominal wall pocket. The device itself acts as an electrode. Most<unk> s nowadays are implanted transvenously with the devices placed in the left pectoral region similar to pacemakers. Intravascular spring or coil electrodes are used to defibrillate. The devices have become smaller and less invasive as the technology advances. Current<unk> s weigh only 70 grams and are about 12.9 mm thick. A recent study by Birnie and colleagues at the University of Ottawa Heart Institute has demonstrated that<unk> s are underused in both the United States and Canada. An accompanying editorial by Dr. Chris Simpson of Queen's University explores some of the economic, geographic, social and political reasons for this.
Implantable cardioverter-defibrillator
Transvenous pacing
Transcutaneous pacing
Pericardial window
Cardioversion
Cardiac pacemaker
Defibrillation
Automated external defibrillator