The American Heart Association recently released data on cardiovascular mortality for the last decade. In the period from 1996 to 2006, the cardiovascular mortality rate in the United States dropped by an impressive 29.2 percent. In spite of this improvement, there remain about 350,000 sudden cardiac deaths per year in the United States. 

 

While there are several reasons for the improvement, the three factors that are likely most important are:

Sadly, the utilization of these defibrillators remains relatively low. Some estimates show that less than a third of patients who need them have them. The resistance to their use is largely one of the patient and physician not realizing the appropriate role of a prophylactic defibrillator. Other impediments include a perception that the quality of life is impaired or that this is exceptionally expensive, both of which are not true. 

 

While we don’t have recent data on cost-effectiveness, we do have data from eight years ago. At that time, the cost of an ICD was about $26,000 per life-year saved. Since that time, the cost of ICDs has fallen about 20 percent and the longevity of the batteries has increased by nearly 100 percent. Therefore, the cost per life-year saved would be much lower. Even the $26,000 per life-year saved is well within the cost range of other well-accepted therapies and half the cost of dialysis.

 

That quality of life with ICDs has been studied and is actually quite high. The patients with a poor outcome are those with inappropriate shocks, especially multiple shocks. Fortunately, this is now quite uncommon.  

 

There have been several, large well-designed clinical trials demonstrating remarkable mortality improvements with the implantation of ICDs. The MADIT, MADIT II and MUST studies all revealed that for patients who are at a high risk for ventricular tachyarrhythmia, prophylactic therapy with an implanted defibrillator leads to improved survival as compared with conventional medical therapy. The largest randomized study was the SCDHeFT trial. It revealed that ICDs reduced the mortality in patients with congestive heart failure (CHF) and an ejection fraction of less than 0.36 by 23 percent as compared with placebo and with amiodarone. Further, it revealed that amiodarone was not different than placebo. 

 

Recently, a new “real world” study of ICDs was published. The authors identified patients with congestive heart failure who were at least 65 years old and met the usual criteria for ICD implantation, had a left ventricular ejection fraction of less than 0.36 and an admission for congestive heart failure. There were 4,685 patients included in the study. All were followed for mortality using the Medicare database. They were stratified by whether or not they had an ICD in place. The principal outcome measure was all cause mortality at three years. The average age was 75.2 years with 60 percent of the patients being women. The average ejection fraction was 0.25. Only 8 percent of these patients received an ICD before being discharged from the hospital. The results demonstrated the mortality was significantly improved in the patients who received an ICD. The mortality was 19.8 percent vs. 27.6 percent at one year, 30.9 percent vs. 41.9 percent at two years and 38.1 percent vs. 52.3 percent at three years. See illustration.

These data reveal the mortality improvement with ICDs is quite high. The vast majority of patients with systolic congestive heart failure, in whom sudden death would be a bad thing, should have an ICD implanted. There should be an effort made to make this standard-of-care therapy available to all appropriate patients.