Medical devices are divided into three classes (I, II, or III) depending on their "risk." Pacemakers and ICDs are considered "high risk" devices (Class III) because people's lives or health may very well depend on the adequate function of these devices.
So how does a new pacemaker go from the drawing board on the inventor's desk at a manufacturer to being ready for implant into the human body? It has to be approved by the Food & Drug Administration (FDA). For Class III devices, the process is called pre-market approval or PMA.
A PMA is actually an application that a company makes to the FDA asking for its new pacemaker or ICD (or other high-risk device) to be commercially cleared for release. In other words, the company wants to be able to start selling its products to the American healthcare consumer.
Part of the PMA process involves collecting data on the device. The FDA is mainly interested in safety (which is self explanatory) and efficacy (which is a fancy term that means the device does what it says it does). Among the information that the FDA wants to see in a PMA are data from scientific studies proving the device is safe and efficacious.
In order to get that data, the manufacturer conducts studies or arranges for third parties to conduct studies on its behalf. The system works on checks-and-balances, that is, the manufacturers run the studies but the FDA has to approve them.
If the company can show the FDA sufficient data backing up its product, the product is cleared for market release. At that point, the paperwork of the PMA, including most of the study data, product manuals, and some correspondence, is made public.
The JAMA paper is the first time (to my knowledge–I may be wrong here) that anyone has gone back and dug through the studies used to support PMAs.
No one is charging that the process for approving pacemakers is flawed. The PMA methodology of submitting scientific study data to support a product's claims seems to be working. The notion that manufacturers conduct the studies and the FDA approves them has not been called into question, either. The problem raised in the Dhruva article in JAMA is this: the scientific data used to support these PMAs is not as scientifically rigorous as it ought to be.
Are they right? The JAMA article makes a pretty compelling case, but we do not know exactly why manufacturers ran the studies the way they did and why the FDA accepted them. There may be more to the story than we are seeing.
Furthermore, there are a lot of pressures right now on the entire healthcare industry. Americans want better medical care at lower prices and faster turnaround times from the FDA. In demanding so much, it appears we have come up short in some areas. The problem may not be that studies were imperfect but that we need to make hard choices: do we want more stringent, scientifically sound cardiac device approvals and, if so, are we willing to take the time and pay the cost?
