Dr John Mandrola practices cardiac electrophysiology in Louisville, KY. He finished training at Indiana University in 1996. His practice encompasses catheter ablation, including an eight-year experience with AF ablation, device implantation, and consultative EP. Outside of the EP lab, Dr Mandrola's two hobbies include competitive cycling and writing. He has maintained a medical, fitness, and cycling blog, Dr John M, for the past two years.
Trials and Fibrillations with Dr John MandrolaView all posts »
Help in the management of Riata ICD leads--from the FDA?Aug 17, 2012 02:33 EDT
It's unrelenting. The bad news just won't stop.
This could only mean yet another story concerning St Jude Medical's Riata family of ICD leads. The troubled leads were recalled in December 2011 after it became clear that they were prone to dramatic and sudden insulation failures in which the lead can externalize in the vasculature, result in inappropriate shocks, or fail to pace or defibrillate. It's a major understatement to say patients with these leads pose vexing clinical management problems. It's no small matter to revise or extract Riata leads. Warning systems such as remote monitoring may not predict lead failures. Tragically, a high-voltage shock—that's needed to defibrillate—can result in shorting of the system and absence of therapy.
Keep in mind too, that in many cases, these potential harm-creators were implanted in asymptomatic patients—who were more likely not to need a shock. (Think numbers needed to treat in the primary-prevention trials.)
Electrophysiologists are struggling mightily. I know I am.
To the news:
Yesterday, the US Food and Drug Administration forcefully inserted itself into the clinical management of patients with Riata leads. The press release was clear and strongly worded. The FDA recommended that patients with a Riata lead undergo "X-rays or other imaging alternatives to check for abnormalities in the insulation surrounding the lead." In addition, it also required St Jude Medical to conduct postmarket surveillance studies on two models of its LV/CRT leads and its currently approved Durata family of leads.
I know what you are thinking: Here we go again—not another Riata story. I wondered the same thing. For the FDA to have made such a bold recommendation, there must have been new news.
No. It turns out that there is no new study on Riata. Rather, I learned from this Wall Street Journal article (published two hours after the press release) that the FDA has been "amalgamizing" the scientific data on Riata and has come up with a few helpful recommendations.
So you ask: What's the big deal? Get an X-ray. And why shouldn't St Jude Medical study Durata closely? It's a lead that shares design similarities to Riata. It could fail, too.
Let me tell you why these simple and well-meaning recommendations trouble me—and why they should trouble you.
Start with this given. I'm absolutely (not 99.9%, but 100%) certain of one fact concerning Riata:
Nobody knows the best way to manage these leads. Not the professors, not us masters of obvious in the clinical world, and surely not the amalgamizers in cubicles at the FDA. The only fair words to use in describing this situation are:
We do not know.
So what do (some) doctors do when they don't know? They default to doing more tests; to be sure, to learn more, and as the FDA press release wishfully suggests: "to help healthcare providers develop individualized patient treatment plans."
Treating uncertainty with willy-nilly testing is one of the most commonly made mistakes in clinical medicine. One of the first lessons young doctors learn is not to do tests unless the results will change what they do. In the specific case of Riata, doing X-rays to determine insulation breaches isn't likely to change what we recommend. For instance, we know that most externalized Riata leads function normally. We also know that normal-appearing Riata leads can fail abruptly. Most important, we know that extraction (or revision) of Riata leads exposes the patient to significant risk. In other words, a negative test doesn't necessarily reassure, and a positive test doesn't always mean trouble.
That's not to say looking for insulation breaches in selected patients isn't helpful. It is. But that's not what the FDA's words say. They don't urge doctors to consider doing X-rays in selected patients; they say patients with Riata "should have" X-rays.
In other words, they make it a medical error not to do a test. It is an ominous precedent when a powerful agency inserts protocol and dogma into a situation best handled with nuance and shared decision-making. I'm surprised and disappointed. I would have thought the tailwinds from the less-is-more and Choosing Wisely movements would have pervaded at the FDA. This powerful agency should well know of the dangers of widespread testing in asymptomatic patients.
That's the doctor side of the argument. It's not the strongest one against the FDA's decree.
Consider the patients' side of the issue. When faced with difficult clinical decisions, I like to put myself in the patient's shoes. What if you had a Riata lead? Would you want an X-ray? If so, how often would you expose yourself to the radiation? And if your lead were externalized but functioning normally, what then? I guess worrying about it would help. That's the thing: patients with Riata leads aren't all the same. A young pacemaker-dependent patient with a Riata lead attached to an older-generation generator (one that does not have remote monitoring capability) may be managed differently from an older patient with a primary-prevention indication. Likewise, if the FDA folks took care of real patients, they would understand that some patients would be devastated to know that their normally functioning lead had an externalization.
The bottom line:
Patients with Riata leads need to be considered carefully and individually. There is no protocol or right answer. Physicians need to keep abreast of the rapidly emerging science on the matter. As we have learned with prior hardware recalls, with time and continued surveillance, a clearer picture emerges. Although we want to protect our patients, for it is we who implanted the troubled lead, it is often the case that doing things isn't always the best answer. Alas, doing things got us into this mess.
Let's close on a positive note. I agree with the FDA's requirement that St Jude closely study its current ICD lead Durata. Here, the FDA is right; Durata shares enough similarities to Riata to make us worry about long-term performance. Enhanced postmarket surveillance of ICD leads should not be controversial. In fact, I would think St Jude would welcome the opportunity to prove to its customers that Durata is reliable. As an implanter of ICDs bent on minimizing harm, I look forward to these studies.