Wednesday, May 17, 2006

Guidant: What We're Not Hearing at the HRS Meeting

It seems Guidant, now a division of Boston Scientific, might have some other news we're NOT hearing about at the Heart Rhythm Society meeting in Boston this week.

As most of us doctors in the field of heart rhythm disorders know, Guidant has been struggling to ressurrect itself from legal problems regarding disclosure of problems with implantable cardiac defibrillators. To reassure investors, a new wireless transmission system, Lattitude Latitude, was developed using the frequency bandwidth of approximately 900MHz (update 18May06: 913-924MHz), the same as cellular phones and some patient telemetry systems in hospitals, that permits communication with their device to interrogate their Contak Renewal 3 ICD to alert patients and doctors about changes in electrical characteristics about the device. The Lattitude system can also be cleverly connected to a weight scale at home so the patient can transmit their weight along with ICD statistics to a central registry database offering additional therapeutic information to physicians about their patient's condition.

Well, wouldn't you know, the system has considerable interference issues with cell phones, electrical noise, and even some telemetry services in hospitals. Yet no patient or physician safety advisory has been issued. It would hurt sales.

To be fair, the problem does not cause reprogramming of the patient's device, but rather interruptions with the downloading of information from the patient's device.

But where's the reassurance to investors, doctors, hospitals, and most of all, patients when these issues are not disclosed?

Medtronic's wireless system for their Virtuoso and Concerto ICD and CRT-D product lines was developed under a special 2.5GHz 402-405MHz mixed bandwidth (used for some weather balloons and a bandwidth reserved for medical device use to avoid such interference), was just approved by the FDA the day before yesterday. As usual, Medtronic is late to the wireless ICD party, but did its homework before jumping on the easy-to-engineer 900MHz bandwidth for their wireless device.


For purposes of disclosure, I do serve on the speaking bureau for Medtronic, but hold no other financial positions with either company mentioned in this post.

Update: 18 May 2006: Seems there have been documented interference issues, particularly in hospitals, with a commercially-available Spectralink phone systems that use the same frequency band. It is routine for Guidant to "sweep" hospitals for such sources of interference before deploying the technology.

No comments: