|via NHLBI website; image on left is an ICD, right is pacemaker|
There is plenty of evidence about which patients benefit from these devices, but also clear evidence about those who do not benefit. What was surprising about the study is the number of people getting the ICD implanted in groups that are known not to benefit from it.
A really good perspective on why this might be the case is offered by Harlan Krumholz, a cardiologist on the Board of Trustees at the American College of Cardiology. Of course, guidelines cannot cover all circumstances, and there are cases where going against guidelines could be a reasonable decision if the patient is given full disclosure and understands the risks and benefits.
This study also highlights how important patient registries are becoming in monitoring outcomes. The federal government, through Medicare/Medicaid, pays for a lot of ICD implantations and thus required the formation of a registry to track these outcomes.
The results of the study may prompt stricter criteria from CMS on the implantation of ICDs or perhaps stricter controls on who can implant them. I assumed the majority of ICDs were being implanted by electrophysiologists, but it turns out quite a few cardiologists, thoracic surgeons and even other specialists are implanting them.
As with any procedure, it is always best to go to someone who does a high volume of cases. Ultimately, the decision to implant an ICD is best made in consultation with a physician who knows you well and when you are clear on the risks and benefits of the procedure given your particular situation.