Sunday, September 14, 2008

DFT testing may have little bearing on the efficacy of shocks

Thanks everyone for a successful meeting! Here’s the link I promised regarding our discussion whether DFT (Defibrillation Threshold) testing is still necessary at the time of implantation.

According to the article, new analysis indicates that DFT testing has little bearing on the efficacy of delivered shocks or long-term mortality. It quotes Dr. Joseph Blatt (University of Washington, Seattle), who says that “when we look carefully at the data, we don’t really see that it provides any particular benefit.”

DFT Testing puts a patient under further risk of sudden death. It’s a low risk (<0.1%), but is it really worth it?

This is from the book The Nuts and Bolts of ICD Therapy (by Tom Kenny, Blackwell Publishing, 2005.)

“In some cases, the implanting physician may opt to forego DFT testing because it is painful, time-consuming, and consumes battery energy, If the implanting physician intends to program the device to maximum output anyway, DFT testing (which would allow programming less than maximum output values) may not be worth the effort. Furthermore, many patients are likely to be shocked only rarely and then for serious situations. For such patients, programming maximum energy therapy is appropriate, and DFT testing is not necessary. Increasingly, DFT testing is omitted at implant. However, when performed, DFT testing can help physicians optimize the output settings of the device.

The goal of any DFT test is first to induce an arrhythmia and then to allow the device to shock the patient and convert the rhythm. If DFT testing is to be conducted, the anesthesiologist should be advised to administer deeper sedation, since this portion of the procedure is definitely considered painful. The entire team should be readied. At the programmer, it may be necessary to select options for DFT testing, since many devices offer a variety of ways to do this sort of testing.”

1 comment:

Julia Lloyd said...

thanks for posting this info... very interesting.