The coffee urns were steaming and the Danishes were piled high. It was a little before 9am on a rainy Thursday in May, 2003. The FDA’s Circulatory System Devices Panel was convening again at the Gaithersburg Holiday Inn. Professor Calkins went through his notes for the big presentation one more time. Others read the Wall Street Journal or looked through their information packets.
Calkins, taking time out from his big pulmonary vein ablation study, was there in order to persuade his friends and colleagues on the panel to approve Cardima’s REVELATION Tx cardiac catheter ablation system. It was an elaborately choreographed Power Point presentation, which would work nicely in the newly renovated Walker/Whetstone Room.
On the street out front, first responders were in full swing at the scene of a gory head-on collision that tied up traffic and made a couple of sales reps from Medtronic late for the meeting. At 9:18, Chairman Warren K. Laskey, M.D. looked at his Rolex. He tapped his microphone. The doctors put their Danishes down and the meeting came to order.
Before Hugh Calkins could get in there and pitch for Cardima, there was other business to be dealt with, and pretty grim business at that. Laskey told the group that “Before we commence with the topic of the day, there will be a brief presentation by Marian Kroen of the FDA …”
Marian had been dispatched from the Issues Management staff at the ominous-sounding Office of Surveillance and Biometrics to alert the cardiology world to a potential danger. Two people had died, or, in the parlance of the trade, there had been adverse events involving Medtronic products.
Medtronic makes some sophisticated gadgets. They make implantable medicine pumps, and stents for clogged arteries. They make neurostimulators, which are electrodes buried deep in the brain to help Parkinson’s disease patients. For stubborn muscle pain, there is diathermy, which is basically a way to warm up your muscles via microwave.
A couple of people who had both stimulators in their brains and sore backs went to get their muscles microwaved. They fell asleep and never woke up. Medtronic and the FDA had done some tests to figure out what exactly had felled the victims, and an autopsy was performed on one of the expired medical consumers.
Conclusion: A deadly interaction of the two Medtronic devices.
It seems that sometimes the electromagnetic field from the diathermy heating pads cause the electrode tips stimulating a person’s brain to turn red hot, which cooks the brain from the inside out. The good news is that because the brain has no pain receptors, the victims don’t feel a thing, which I suppose would count as a victory in the eyes of the director of the pain clinic.
“So what did the FDA do?” said Marian, “We reached into our toolbox and took some actions.” Bold actions. The FDA made Medtronic put bigger warning labels on the packages of both devices, so that both neurosurgeons and pain docs could beware the broiled brain.
Some of the cardiologists seemed impatient, What’s this got to do with us?
“As you all know,” said Marian, “Cardiac ablation happens at around 50 to 55 degrees Celsius… ” The cardiologists did indeed know that when a wire inserted into the heart raises nearby tissue to about 130°F it kills that tissue, which creates scar tissue, which blocks the pathway of rogue electrical beats that cause your heart to quiver.
That’s the idea anyway.
Her point was that there may have been adverse interactions between pacemakers, defibrillators and diathermy—as a matter of fact there should have been—but there were no reports.
How can that be?
Collateral Damage: A Patient, a New Procedure and the Learning Curve 