The New York Times published an article in their business section (interesting location to put such an article, but I digress) about extracting the Medtronic's advisory Sprint Fidelis defibrillator "cable" recently. (Note to their editors, it's actually a "defibrillator lead" containing multiple wires, not a "cable.") The article quotes some of the best and brightest in the lead extraction field - all of whom are truly experts at the task. It is interesting to note the differences in management style that these guys display: some (Wilkoff) would re-use the lead when it comes times for generator change, while others advise removing the lead at the time of a defibrillator generator (battery) change. There is little mention about placing a new lead next to the old one. Instead, the article suggests that "leaving it in place can make it more difficult to remove later, because of in-grown tissue."
No, that is not the reason to have the lead extracted. On the contrary, that's a reason to leave the lead in place so you can avoid the potential risk of tearing one of the great vessels and bleeding to death during the extraction procedure. After 6 months most of these leads have their "ingrowth" of tissue well-established. The "ingrowth" is not like a cancer that continues to grow. It can become more dense and even calcified over time, however, and the amount of ingrowth varies patient to patient.
Most experienced explanters look for certain characteristics on any lead that needs to be extracted to determine the potential difficulties they might encounter. Leads with more shocking coils are usually more difficult to extract because the coils often become adherent to tissue. Also, leads that passivly fix to the heart by scar formation tend to be harder to extract compared to those that actively screw into the heart muscle (and can have the screw retracted before removal). These are some of the bigger factors to explain why some of these leads come out more easily than others.
Admittedly, sometimes the lead must be extracted because the blood vessel into which the original lead was inserted became completely occluded and a new lead simply cannot be placed next to the old one without removing the old one first. Sometimes there's a desire not to implant a new device from the opposite chest area because of anatomic issues, like a prior mastectomy. Or maybe the lead has become infected, then it MUST be removed because, like a splinter festering in your foot, the infection will never resolve unless the lead is removed in its entirety. These reasons I'd buy as reasons to consider lead extraction. Also, patient preference of anxiety influences the decision to remove the lead, sometimes despite the doctor's best attempts at suggesting alternatives. There will always be a few of these.
But if it is at all possible to place a new lead at the time of battery change, that's seems like a reasonable compromise to me that avoids most future issues with the advisory lead. Certainly, Dr. Wilcoff thinks that the fracture rate is low enough that he'd just re-use it. While this conservative approach might make sense in most instances, is more difficult to justify when a patient is pacemaker-dependent and must have a normally functioning lead at all times for their heart to beat. In these cases, placement of a new lead, especially at the time of device battery change when the risk of infection is unavoidable, might warrant a more aggressive approach to avoid a potentially fatal complication should the lead later fracture. But what to do if the implant vessel is completely occluded and no room exists to place a new lead in such a pacemaker-dependent patient? This is where the toughest clinical issue lies: do you implant a whole new system from the contra-lateral side or just a pace-sense lead and then tunnel the lead to the same side as the others? Or do you extract the lead to make room for a new one? Given the risks involved with extraction, it's hard to know if the "cure" is worse than the disease.
What is certain is that patients with this lead should discuss all of these potential eventualities with their cardiologist or electrophysiololgist before any surgery takes place to develop a game plan should any of these challenges be encountered during routine device battery-change surgeries.
-Wes
Showing posts with label Sprint Fidelis. Show all posts
Showing posts with label Sprint Fidelis. Show all posts
Wednesday, April 08, 2009
Friday, March 13, 2009
Medtronic Updates Doctors on Sprint Fidelis Defibrillator Lead
In anticipation of an upcoming New York Times article to run this weekend, I just received my 'dear doctor' letter from Medtronic updating the status of their advisory Sprint Fidelis defibrillator lead. Reportedly, the NYT article will highlight a recently reported study published online before print from the medical journal Heart Rhythm that describes a higher-than anticipated failure rate from the lead. These data are in contrast to other published data assembled in Medtronic's 'Dear Doctor' letter.
While there is probably no larger cardiac device concern for electrophysiologists and their affected patients, Medtronic's disclosure with patient management recommendations based on Hauser's data and others before the release of the upcoming article in the New York Times is appreciated and should assist patients and doctors as they discuss their treatment options. Importantly, Medtronic points out:
...Monday should be interesting.
-Wes
Addendum:
NYT article 13 Mar 2009: "Medtronic Links Device for Heart to 13 Deaths"
Dr. Wes: Medtronic's Sprint Fidelis Performance Lead Update - May 13, 2008
Dr. Wes: Challenges With a Lead Recall - Oct 17, 2007
Dr. Wes: More on Medtronics Sprint Fidelis Advisory - Oct 15, 2007
While there is probably no larger cardiac device concern for electrophysiologists and their affected patients, Medtronic's disclosure with patient management recommendations based on Hauser's data and others before the release of the upcoming article in the New York Times is appreciated and should assist patients and doctors as they discuss their treatment options. Importantly, Medtronic points out:
"The FDA’s MAUDE database currently has 107 Medical Device Reports (MDRs) that include allegations that the Fidelis lead may have caused or contributed to a patient death. Most of these MDRs were not initiated by medical professionals; the majority were initiated by family members or attorneys with minimal supporting data. Medtronic’s Independent Physician Quality Panel has reviewed 89 of the 107 reports. It is not possible to determine cause of death with certainty. The Panel has identified 13 patient deaths in which a Sprint Fidelis lead fracture may have been a possible or likely contributing factor.So we'll see that the news article says, but one thing's for sure...
The Panel noted that four of the 13 deaths were associated with lead extraction, highlighting the risks associated with that procedure. With the exception of the appearance of deaths associated with lead extraction, no new or unexpected trends have been observed."
...Monday should be interesting.
-Wes
Addendum:
NYT article 13 Mar 2009: "Medtronic Links Device for Heart to 13 Deaths"
Dr. Wes: Medtronic's Sprint Fidelis Performance Lead Update - May 13, 2008
Dr. Wes: Challenges With a Lead Recall - Oct 17, 2007
Dr. Wes: More on Medtronics Sprint Fidelis Advisory - Oct 15, 2007
Tuesday, February 24, 2009
More Concerning News About Medtronic's Sprint Fidelis Lead
... was published online before print in the journal Heart Rhythm yesterday:
-Wes
Addendum: The story in the New York Times.
"... the hazard of Sprint Fidelis failure accelerated after the first year and continued to increase during the study. In contrast to other defibrillator leads, the Sprint Fidelis failure rate was significantly higher (3.75%/year vs 0.58%/year) and the 3-year estimated survival significantly lower (87.9%, 95% CI 84.8,90.9 vs 98.5%, 95% CI 97.8, 99.3) (p<0.0001). The chance that a Sprint Fidelis lead would survive another year decreased progressively during the study. Most Sprint Fidelis failures were caused by pace-sense conductor fracture (n=63; 87.5%), which caused inappropriate shocks in 36 of 72 patients."As far as I am aware, no new recommendations from Medtronic regarding the management of these leads has been forthcoming (e.g., the cautious "wait and watch approach" seems best for now), but we certainly have seen our share of patients with this problem.
-Wes
Addendum: The story in the New York Times.
Thursday, December 11, 2008
What Price Safety?
In February, 1996, the FDA issued this directive:
For at least the past three years, the large medical device manufacturers have been developing a new 4-electrode connection system called "IS-4" that promises to supplant the IS-1 connection system. Because the medical device industry has argued that the changes to the IS-1 standard used to implement the IS-4 standard were minor, they applied for pre-market approval through the FDA's 510K exemption that does not require human clinical testing prior to market release of devices, but rather relies on historical information from existing technology supplemented by animal and specialized bench testing. While this approach has worked well for some new defibrillator leads, others have not fared so well.
Earlier, the Medtronic Sprint Fidelis defibrillator lead family, a thinner cousin of prior defibrillator leads, was released under the same 510K exemption ruling of the FDA, but subsequently recalled in October, 2007 after post-market surveillance demonstrated an increased failure rate of this lead family compared to its predecessors. Some 235,000 patients were affected.
Now, just before the release of new defibrillator leads containing the new IS-4 standard connections, Drs. Robert G. Hauser and Adrian K. Almquist of the Minneapolis Heart Institute are sounding their concerns over upcoming release, arguing that human testing should be performed before the lead is released to the public at large. They argue, in part, four concerns:
But the FDA, in their accompanying editorial, countered:
Well, in some respects, they both are. No one can argue that patient safety should take priority in this debate, but at what cost? When we review the failure rates of even a known faulty lead like the Sprint Fidelis, its failure is only slightly higher than prior leads. For instance, the failure rate of a "good" Medtronic Model 6947 Sprint Quatro lead has a 1.9%% failure rate at 3 years, versus the 5% 3-year failure rate of the "bad" Medtronic Sprint Fidelis lead. Detecting a signficant difference of 3 percentage-point failure rate would take two fairly large patient comparison groups randomized and followed for many years to detect such a small difference in failure rate with sufficient statitical power. This would add signficant cost to devices, certainly, and would delay market release of newer innovations. The chilling effect on device development would cause every company to think long and hard before bringing any new technology to market.
But the public has grown wary of lack of regulation in many sectors of our economy, especially that portion that has been ridden roughshod by the financial sector. They are aware that the FDA needs the device manufacturers for their review fees, and hence have become skeptical of the FDA's ability to remain unbiased in their review process. They are no longer naïve about the physical and psychological toll such failures have upon patients, thanks, in part, to the unrelenting press coverage that these recalls generate ("Bad news sells best, 'cause good news is no news.") Regretably, we rarely hear about the lives saved by these devices every day.
The technology boom in medicine is under tremendous pressure to contract as health care costs continue to skyrocket and Congress looks for new ways to cut costs. The days of unfettered capitalism and quick profits in medicine are quickly coming to an end. Hitching the bandwagon to "patient safety" will be a powerful driving force for policy advocates to stifle innovation in the health care sector as we cling to the security of the known during this economic contraction.
What are the implications of the loss of post-market surveillance as a means of determining patient safety? What are the implications for costs of devices going forward? How much are we willing to spend to assure relative safety perfection? How safe is safe enough? Have not the existing standards for device approval resulted in some very beneficial and reliable systems? Must we assume there is too little value or economy to post-market surveillance to permit it's exclusive use for introducing new technology?
There's no question that Drs. Hauser and Almquist make important points. The bigger question might ultimately be: how much do we want to spend?
-Wes
References:
Hauser RG, Almquist AK. "Learning from our mistakes? Testing new ICD technology." N Engl J Med 2008;359:2517-2519.
Shein MJ, Schultz DJ. "Testing New ICD Technology," New Engl J Med 2008; 359: 2610.
"In keeping with its commitment to speed up patient access to new medical devices, FDA is exempting 122 categories of low-risk devices from premarket review, adding to the 450 categories already exempted from such review. Since the exempted devices will no longer have to wait for premarket review, they can reach patients sooner and FDA can shift resources to more critical needs."With the increasing complexity of implantable medical devices and a growing desire to innovate ways to manage patient's chronic medical conditions remotely, there is a need to downsize connections of leads and sensors to the computer electronics of these sophistocated devices. Until now, a standard two-electrode connection system called an "IS-1" standard has been used to connect leads and sensors to the housing of implantable cardiac devices.
For at least the past three years, the large medical device manufacturers have been developing a new 4-electrode connection system called "IS-4" that promises to supplant the IS-1 connection system. Because the medical device industry has argued that the changes to the IS-1 standard used to implement the IS-4 standard were minor, they applied for pre-market approval through the FDA's 510K exemption that does not require human clinical testing prior to market release of devices, but rather relies on historical information from existing technology supplemented by animal and specialized bench testing. While this approach has worked well for some new defibrillator leads, others have not fared so well.
Earlier, the Medtronic Sprint Fidelis defibrillator lead family, a thinner cousin of prior defibrillator leads, was released under the same 510K exemption ruling of the FDA, but subsequently recalled in October, 2007 after post-market surveillance demonstrated an increased failure rate of this lead family compared to its predecessors. Some 235,000 patients were affected.
Now, just before the release of new defibrillator leads containing the new IS-4 standard connections, Drs. Robert G. Hauser and Adrian K. Almquist of the Minneapolis Heart Institute are sounding their concerns over upcoming release, arguing that human testing should be performed before the lead is released to the public at large. They argue, in part, four concerns:
- "In our opinion, the decision by the FDA and industry to forgo premarket clinical testing of the connector is not in the best interest of patients. For starters, the four-pole connector is a complex electromechanical design that requires major changes to the ICD lead and pulse generator; it should therefore be considered an investigational technology."
- "Second, no published study has shown that the results of bench testing or testing in animals accurately predict the clinical reliability of ICD systems. If they did, recalls would be uncommon."
- "Third, there is no medically necessary reason for rapidly deploying the four-pole connector. Current connector systems have been in use for more than a decade and are performing reliably."
- "Fourth, FDA approval would allow the four-pole connection system to be used in patients without the level of informed consent that is usually required for investigational devices. After the recent Supreme Court decision in Riegel v. Medtronic, FDA approval would also leave patients without the ability to sue the manufacturer for compensation for injuries caused by a four-pole connector."
But the FDA, in their accompanying editorial, countered:
"When preclinical studies and existing clinical data support approval and expected long-term failure rates are low, postapproval studies may provide an appropriate means for verifying long-term device performance. Ensuring device safety does not necessarily require that every device be clinically evaluated before marketing. Approval of some implantable leads with IS-4 connectors may be appropriate without new clinical data. The FDA decides what information is needed to support an approval on the basis of its review of an individual application. This is a scientifically sound approach to protecting public health.So which side is right in this debate?
Well, in some respects, they both are. No one can argue that patient safety should take priority in this debate, but at what cost? When we review the failure rates of even a known faulty lead like the Sprint Fidelis, its failure is only slightly higher than prior leads. For instance, the failure rate of a "good" Medtronic Model 6947 Sprint Quatro lead has a 1.9%% failure rate at 3 years, versus the 5% 3-year failure rate of the "bad" Medtronic Sprint Fidelis lead. Detecting a signficant difference of 3 percentage-point failure rate would take two fairly large patient comparison groups randomized and followed for many years to detect such a small difference in failure rate with sufficient statitical power. This would add signficant cost to devices, certainly, and would delay market release of newer innovations. The chilling effect on device development would cause every company to think long and hard before bringing any new technology to market.
But the public has grown wary of lack of regulation in many sectors of our economy, especially that portion that has been ridden roughshod by the financial sector. They are aware that the FDA needs the device manufacturers for their review fees, and hence have become skeptical of the FDA's ability to remain unbiased in their review process. They are no longer naïve about the physical and psychological toll such failures have upon patients, thanks, in part, to the unrelenting press coverage that these recalls generate ("Bad news sells best, 'cause good news is no news.") Regretably, we rarely hear about the lives saved by these devices every day.
The technology boom in medicine is under tremendous pressure to contract as health care costs continue to skyrocket and Congress looks for new ways to cut costs. The days of unfettered capitalism and quick profits in medicine are quickly coming to an end. Hitching the bandwagon to "patient safety" will be a powerful driving force for policy advocates to stifle innovation in the health care sector as we cling to the security of the known during this economic contraction.
What are the implications of the loss of post-market surveillance as a means of determining patient safety? What are the implications for costs of devices going forward? How much are we willing to spend to assure relative safety perfection? How safe is safe enough? Have not the existing standards for device approval resulted in some very beneficial and reliable systems? Must we assume there is too little value or economy to post-market surveillance to permit it's exclusive use for introducing new technology?
There's no question that Drs. Hauser and Almquist make important points. The bigger question might ultimately be: how much do we want to spend?
-Wes
References:
Hauser RG, Almquist AK. "Learning from our mistakes? Testing new ICD technology." N Engl J Med 2008;359:2517-2519.
Shein MJ, Schultz DJ. "Testing New ICD Technology," New Engl J Med 2008; 359: 2610.
Monday, November 03, 2008
Software Said To Reduce Inappropriate ICD Shocks
In October, 2007, Medtronic issued one of the largest defibrillator lead advisory alerts for their popular and thin Model 6949 Sprint Fidelis lead due to the lead's higher-than-expected fracture rate. More recently, a software patch called a Lead Integrity Alert has been developed that can be uploaded into affected patients' defibrillators in hopes of improving the detection of lead fracture conditions. The software also automatically readjusts the settings of the defibrillator to make it less prone to deliver inappropriate shocks caused by lead failure.
Today in Circulation, the efficacy of this algorithm to avoid shocks was published from in vitro testing on leads returned to the manufacturer.* Real life effectivness of the algorithm has not been tested to date. So far, the algorithm theoretically shows improvement in avoiding unnecessary shocks:
The difficult decision will come when there is no venous access in which to place a new lead from the same side as the existing defibrillator. Should we abandon the existing side and place an entirely new system on the opposite side with new, non-recalled leads? Should we send the patient for lead extraction and replacement? Or should we re-connect the old lead and hope for the best if no other option presents itself?
These are not easy decisions.
Patients with Sprint Fidelis leads should discuss what's involved with each of these scenarios with their doctors when the time comes to replace their defibrillator battery. Hopefully, we'll have additional trend data regarding lead survival on which to base future management recommendations. But until we do, battery changes in these patient's with Sprint Fidelis leads will be anything but routine.
-Wes
*The study was funded by Medtronic.
Other information:
Medtronic's Official Sprint Fidelis Information WebSite
TheHeart.org: Updated Lead Failure Rate Information
Medtronic to Pull Its Most Popular Defibrillator Lead
More on the Medtronic's Sprint Fidelis Advisory
Medtronic's Sprint Fidelis Perfomance Lead Update
Today in Circulation, the efficacy of this algorithm to avoid shocks was published from in vitro testing on leads returned to the manufacturer.* Real life effectivness of the algorithm has not been tested to date. So far, the algorithm theoretically shows improvement in avoiding unnecessary shocks:
To reduce inappropriate shocks, the lead-integrity algorithm increases the number of intervals to detect (NID) ventricular fibrillation when triggered. The lead-integrity algorithm was tested on data from 15,970 patients with Fidelis leads (including 121 with clinically diagnosed fractures) and 95 other fractured leads confirmed by analysis of returned product. The effect of the NID on inappropriate shocks was tested in 92 patients with 927 shocks caused by lead fracture. Increasing the NID reduced inappropriate shocks (P<0.0001). The lead-integrity algorithm provided at least a 3-day warning of inappropriate shocks in 76% (95% CI, 66 to 84) of patients versus 55% (95% CI, 43 to 64) for optimal impedance monitoring (P=0.007). Its positive predictive value was 72% for lead fractures and 81% for lead fractures or header-connector problems requiring surgical intervention. The false-positive rate was 1 per 372 patient-years of monitoring.The distribution of the fractures reported was also interesting:
Of the 95 patients in the RPA (returned product analysis) group, 41 (43%) had fractures of the coil conductor to the tip electrode and 54 (57%) had fractures of the cable conductor to the ring electrode. Figure 5 shows that all coil fractures occurred at the anchor sleeve, whereas 52 of the cable fractures (96%) occurred distally or at the bifurcation/trifurcation.We are about to see a rising number of patients with these leads enter the clinical arena as their ICD batteries reach their elective replacement indicators warning us of battery depletion. Recommendations from the company have so far been few, but most suggest a relatively conservative watch and wait approach. But when the patient's ICD pocket is opened for a battery change, the opportunity to place a new, non-recalled lead presents itself and should be considered (provided of course venous access still exists in which to place the new lead).
The difficult decision will come when there is no venous access in which to place a new lead from the same side as the existing defibrillator. Should we abandon the existing side and place an entirely new system on the opposite side with new, non-recalled leads? Should we send the patient for lead extraction and replacement? Or should we re-connect the old lead and hope for the best if no other option presents itself?
These are not easy decisions.
Patients with Sprint Fidelis leads should discuss what's involved with each of these scenarios with their doctors when the time comes to replace their defibrillator battery. Hopefully, we'll have additional trend data regarding lead survival on which to base future management recommendations. But until we do, battery changes in these patient's with Sprint Fidelis leads will be anything but routine.
-Wes
*The study was funded by Medtronic.
Other information:
Medtronic's Official Sprint Fidelis Information WebSite
TheHeart.org: Updated Lead Failure Rate Information
Medtronic to Pull Its Most Popular Defibrillator Lead
More on the Medtronic's Sprint Fidelis Advisory
Medtronic's Sprint Fidelis Perfomance Lead Update
Thursday, September 04, 2008
Software Coming to Help Detect Medtronic Sprint Fidelis Lead Fractures
Sometime next week, we should be receiving software, called the "Lead Integrity Alert" that can be uploaded into existing Medtronic implantable cardiac defibrillators (ICDs) to help detect lead fractures from the recalled Sprint Fidelis (Model 6949) defibrillator leads. This software was approved by the FDA today and can be uploaded into the Medtronic's Marquis, Maximo, Virtuoso and Concerto ICD models non-invasively during a routine office visit. It is thought that such programming changes can reduce the number of patients who receive an inappropriate shock from a lead fracture before it is explanted by 38 to 40%. While not perfect, it might alert both the patient and physician earlier to a avoid unnecessary shocks should a lead fracture.
How the Software Works
There is a so-called Sensing Integrity Counter that usually trips an alert if there are greater than 300 counts of non-physiologic sensed intervals by the device. This software will lower this number to 30 or more to trigger an alert. Further, if there are an excessive number of very short "non-sustained ventricular tachycardia" sensed intervals, this also could trigger an alert. The software also allows an automatic adjustment of the "number of intervals to detect" to be automatically incremented to the next-higher detection ratio in hopes of averting a shock, while beeping six times a day (rather than once) to improve the chances a patient will notice the new alert state if tripped.
What to Do
Patients with the advisory leads will have the software automatically installed during their next routine office device check, but those who want it installed earlier should contact their doctor and inquire if the software could be installed earlier.
Realize this software only affects Medtronic ICDs. St. Jude and Boston Scientific devices are NOT affected.
-Wes
11 Sep 2008 Update: Medtronic's Info on the Lead Integrity Alert.
How the Software Works
There is a so-called Sensing Integrity Counter that usually trips an alert if there are greater than 300 counts of non-physiologic sensed intervals by the device. This software will lower this number to 30 or more to trigger an alert. Further, if there are an excessive number of very short "non-sustained ventricular tachycardia" sensed intervals, this also could trigger an alert. The software also allows an automatic adjustment of the "number of intervals to detect" to be automatically incremented to the next-higher detection ratio in hopes of averting a shock, while beeping six times a day (rather than once) to improve the chances a patient will notice the new alert state if tripped.
What to Do
Patients with the advisory leads will have the software automatically installed during their next routine office device check, but those who want it installed earlier should contact their doctor and inquire if the software could be installed earlier.
Realize this software only affects Medtronic ICDs. St. Jude and Boston Scientific devices are NOT affected.
-Wes
11 Sep 2008 Update: Medtronic's Info on the Lead Integrity Alert.
Tuesday, May 13, 2008
Medtronic's Sprint Fidelis Performance Lead Update
It's now been six months since Medtronic's lead recall of their 7-French Model 6949 Sprint Fidelis defibrillator lead in October 2007. The first update of the lead performance arrived in my office this week, dated 7 May 2008 (you can view it here). With this letter came the first trending data of the failure rates as determined by evaluation of Medtronic's Carelink follow-up database and Returned Product Analysis (RPA) reports as well.While the number of lead failures remains relatively small and current follow-up recommendations have not changed, the failure trends, albeit early, remain concerning. It appears that a continued number of failures throughout the life of the lead can be expected. By Medtronic's analysis of a typical 1000-patient ICD clinic, over the next 12 months, nine (9) patients can be expected to have an anode or cathode failure and half of those patient's will have little warning of an impending fracture.
The implications of these recommendations are far-reaching, for it now seems the fault with the lead was not a physician implant technique problem as originally surmised, but rather a design flaw. Further, when it comes to replacing these patient's defibrillator batteries over the next four or five years, electrophysiologists will likely be advised to replace the 6949 lead with a more reliable defibrillator lead model, like the 6947, increasing the difficulty of a typical device battery change procedure.
-Wes
Friday, March 07, 2008
A Conversation I Never Want to Have
Mr. Smith, welcome back to the real world!
Did you know that your heart stopped earlier today, but thanks to your friendly neighborhood paramedic and a handy-dandy AED, we got it going again?
Amazing, huh?
We've done an extensive evaluation of your medical condition, Mr. Smith, and we think you need to have and ICD implanted.
What's that? Oh, an "ICD" is short for a implantable cardioverter defibrillator. It's a little device we implant under your skin that is attached to special wires we place in your heart that monitors your heart rhythm, so that should this happen again, the device can automatically detect, charge, and shock your heart back to normal rhythm lickety split.
Sound good? Great!
Now, a few things I need to ask you: we have three main manufacturers that make these devices here in the US: Medtronic, Boston Scientific, and St. Jude Medical. If those don't sound good, you can alternatively have us special-order you a device from Germany called a Biotronik device. It might cost you a bit more and I'm not sure there will always be a rep available to help check the device, but hey, we want to keep you well informed about ALL possibilities. Any preference?
What's that you say, you're not sure? Well, here's some more information:
The safety record for each of these manufacturers has been pretty good, but once in a while there have been some problems with recalls of leads and batteries of these devices. When this happens, believe it or not these suckers can explode inside your chest with lots of great big shocks and maybe even kill you. I'm not kidding. Really. Now admittedly this happens infrequently, but hey, I just want you to know about this. We want you informed. There's even legal action pending against all of the manufacturers. Did you know this? Now the FDA has all kinds of requirements that they make these device companies jump through, but you know, they've been a bit short-staffed lately. But they're getting stricker now. I mean they check everything now - heck new products? Well, they're still checking out the old ones. Oh, and those overseas plants that make parts? Well the FDA has to keep checking those too.
How often are there problems? Well, I'm so glad you asked!
Here's the manufacturers' published safety statistics for Boston Scientific, Medtronic, St. Jude. Study this information carefully. I really don't want you making the wrong decision! What's that you say? You're not sure if you should have one? But the data are so CLEAR!
Oh well, that's your decision, Mr. Smith. Never mind that you saw God earlier today.
Hey, at least I feel good you're now COMPLETELY informed!
* * *
It's easy to criticize our current system of checks and balances for medical device safety, as William H. Maisel, MD, MPH does so well in the New England Journal of Medicine this week. And while he makes some good points about the need for consideration of better overview of pre-release testing of new devices to the market, can we really expect that patients can understand all of the implications of ICD type, safety information, and implications for their care just after they've suffered an episode of aborted sudden death?
With remarkable failure to acknowledge efforts by the FDA, Heart Rhythm Society, and manufacturers already underway to improve post-market performance evaluations, he writes:
Certainly, we should always strive for improved patient safety. But to suggest that efforts are not underway to assure timely reporting of post-market performance analysis flies in the face of the many countless individuals who have devoted huge personal effort and resources to continually improve this endeavor.
Maybe, just maybe, we should empower the doctors to present the data to the patient, rather than impose more governmental regulation.
No. I forgot.
In the medicine of today, bureaucracy always wins.
-Wes
Did you know that your heart stopped earlier today, but thanks to your friendly neighborhood paramedic and a handy-dandy AED, we got it going again?
Amazing, huh?
We've done an extensive evaluation of your medical condition, Mr. Smith, and we think you need to have and ICD implanted.
What's that? Oh, an "ICD" is short for a implantable cardioverter defibrillator. It's a little device we implant under your skin that is attached to special wires we place in your heart that monitors your heart rhythm, so that should this happen again, the device can automatically detect, charge, and shock your heart back to normal rhythm lickety split.
Sound good? Great!
Now, a few things I need to ask you: we have three main manufacturers that make these devices here in the US: Medtronic, Boston Scientific, and St. Jude Medical. If those don't sound good, you can alternatively have us special-order you a device from Germany called a Biotronik device. It might cost you a bit more and I'm not sure there will always be a rep available to help check the device, but hey, we want to keep you well informed about ALL possibilities. Any preference?
What's that you say, you're not sure? Well, here's some more information:
The safety record for each of these manufacturers has been pretty good, but once in a while there have been some problems with recalls of leads and batteries of these devices. When this happens, believe it or not these suckers can explode inside your chest with lots of great big shocks and maybe even kill you. I'm not kidding. Really. Now admittedly this happens infrequently, but hey, I just want you to know about this. We want you informed. There's even legal action pending against all of the manufacturers. Did you know this? Now the FDA has all kinds of requirements that they make these device companies jump through, but you know, they've been a bit short-staffed lately. But they're getting stricker now. I mean they check everything now - heck new products? Well, they're still checking out the old ones. Oh, and those overseas plants that make parts? Well the FDA has to keep checking those too.
How often are there problems? Well, I'm so glad you asked!
Here's the manufacturers' published safety statistics for Boston Scientific, Medtronic, St. Jude. Study this information carefully. I really don't want you making the wrong decision! What's that you say? You're not sure if you should have one? But the data are so CLEAR!
Oh well, that's your decision, Mr. Smith. Never mind that you saw God earlier today.
Hey, at least I feel good you're now COMPLETELY informed!
It's easy to criticize our current system of checks and balances for medical device safety, as William H. Maisel, MD, MPH does so well in the New England Journal of Medicine this week. And while he makes some good points about the need for consideration of better overview of pre-release testing of new devices to the market, can we really expect that patients can understand all of the implications of ICD type, safety information, and implications for their care just after they've suffered an episode of aborted sudden death?
With remarkable failure to acknowledge efforts by the FDA, Heart Rhythm Society, and manufacturers already underway to improve post-market performance evaluations, he writes:
According to its mission statement, the FDA is "responsible for protecting the public health" and for "helping the public get the accurate, science-based information they need." Unfortunately, the agency is failing to fulfill that mission. In 1998, the Advisory Commission on Consumer Protection and Quality in the Health Care Industry adopted a Patients' Bill of Rights whose primary tenet is that patients have "the right to receive accurate, easily understood information to assist them in making informed decisions." Regrettably, patients considering implantation of medical devices often fail to receive critical information on device safety.Should patients be faced with all available safety information when they present as the fictional patient above does? And what about the product performance report references that are already published, updated quarterly, and available on the web? Should they be given the opportunity to scour these data before signing their surgical consents? Should the data be updated weekly? Will patients be able to understand these data and the nuances of the recalls underway? How much more "safety data" will patient's need to absorb to meet Dr. Maisel's expectations for full "disclosure?"
Certainly, we should always strive for improved patient safety. But to suggest that efforts are not underway to assure timely reporting of post-market performance analysis flies in the face of the many countless individuals who have devoted huge personal effort and resources to continually improve this endeavor.
Maybe, just maybe, we should empower the doctors to present the data to the patient, rather than impose more governmental regulation.
No. I forgot.
In the medicine of today, bureaucracy always wins.
-Wes
Thursday, December 13, 2007
More on Medtronic's Sprint Fidelis Lead
... recall appears in the New York Times today.
The issue regarding replacing these leads in pacemaker-dependent patients is raised in the article. This is a tough decision. It is clear that some are recommending extraction of leads in this case and at first blush, this might be appropriate. But the risk of introducing an infection anytime a pocket is opened remains. This risk is about 1%, even in experienced centers. Is the risk of replacement worth this? We have little data to know at this time. Unfortunately, we do not know if the incidence of lead fracture stays constant, increases, or decreases with time. This is important information and will only come as additional follow-up of these leads is forthcoming. If the risk of fracture is greatest in the first few months after implant, and then tapers off, perhaps NOT replacing a more chronic lead will become the more advisable approach. If it increases with time, then extraction might be worth the risk.
What is certain right now, is that none of us has the right answer - so patients should have a thorough discussion with their doctors about all of the pros and cons about lead extraction. Believe me, lead extraction is not always as easy as the Spectranetics company (with their video that accompanies the NYT article) would suggest.
-Wes
The issue regarding replacing these leads in pacemaker-dependent patients is raised in the article. This is a tough decision. It is clear that some are recommending extraction of leads in this case and at first blush, this might be appropriate. But the risk of introducing an infection anytime a pocket is opened remains. This risk is about 1%, even in experienced centers. Is the risk of replacement worth this? We have little data to know at this time. Unfortunately, we do not know if the incidence of lead fracture stays constant, increases, or decreases with time. This is important information and will only come as additional follow-up of these leads is forthcoming. If the risk of fracture is greatest in the first few months after implant, and then tapers off, perhaps NOT replacing a more chronic lead will become the more advisable approach. If it increases with time, then extraction might be worth the risk.
What is certain right now, is that none of us has the right answer - so patients should have a thorough discussion with their doctors about all of the pros and cons about lead extraction. Believe me, lead extraction is not always as easy as the Spectranetics company (with their video that accompanies the NYT article) would suggest.
-Wes
Saturday, October 20, 2007
Office Heroics
To the heroic office staff all over the world who have worked hard to notify patients about the Medtronic's Sprint Fidelis lead recall this week, I offer this short video by Zack Lipovsky:
-Wes
-Wes
Friday, October 19, 2007
Kick 'em When They're Down
The hallmark of junk science reporting is quoting statistics out of context.
“Heart Wires May Pose More Risk for the Young” was the title of the article (subscription) in the Wall Street Journal this morning. The article noted the work of a fellow Northwestern University pediatric cardiologist, Wayne H. Franklin, MD who found preliminary data of higher than expected lead fracture rates in children with congenital heart disease under the age of 21. Dr. Franklin pooled data from 32 institutions who specialize in treating pediatric patients had noted a fracture rate of 6.7% of 569 patients with Medtronic’s Sprint Fidelis lead compared to Medtronic’s quoted 2.3% failure rate in the overall defibrillator population.
But what the article failed to mention was that failure rates of all types of transvenous pacing and defibrillator leads are always higher in children than in adults:
-Wes
“Heart Wires May Pose More Risk for the Young” was the title of the article (subscription) in the Wall Street Journal this morning. The article noted the work of a fellow Northwestern University pediatric cardiologist, Wayne H. Franklin, MD who found preliminary data of higher than expected lead fracture rates in children with congenital heart disease under the age of 21. Dr. Franklin pooled data from 32 institutions who specialize in treating pediatric patients had noted a fracture rate of 6.7% of 569 patients with Medtronic’s Sprint Fidelis lead compared to Medtronic’s quoted 2.3% failure rate in the overall defibrillator population.
But what the article failed to mention was that failure rates of all types of transvenous pacing and defibrillator leads are always higher in children than in adults:
Current practice suggests that transvenous pacing leads routinely can be placed in children weighing more than 10 kg. This figure is likely to continue to decrease as pacing technology continues to reduce lead body diameter. Because of continued growth and vigorous activity, however, pediatric patients have lead fracture and failure rates distinctly higher than adults. Actual survival comparisons have been performed for transvenous pacing leads in children. These comparisons show progressive lead failure over time from fracture, insulation discontinuities, adapter/header failures, or pacing exit block.While I have no argument with the findings of Dr. Franklin, journalists using these specialists’ data to produce sensationalist headlines for business interests which serve to panic pediatric patients and families already in a difficult and fragile situation is irresponsible. I mean, is there another dog we can kick?
-Wes
Wednesday, October 17, 2007
Challenges with a Lead Recall
Not surprisingly, the inevitable investigations and litigation regarding the Sprint Fidelis lead situation has started:
Then again, maybe not.
I thought it would be informative to check the FDA's MAUDE database for Medtronic's "safe" Sprint Quattro leads, and check on the number of deaths with that lead since 1/2005. And you know what? There are four deaths not related to infection. Hmm. 4 of 126,400 implants of Quattro leads (1 in 31,600) verses five of 268,000 implants of the "faulty" Sprint Fidelis (1 in 53,600). These data seem to support the Sprint Fidelis as less lethal than the Quattro. Could this be true? Admittedly, the FDA's MAUDE database is not the best place to evaluate such occurrences, but the point remains: verifying if the cause of death in an individual patient was actually caused by the lead itself is difficult - the circumstances of each death must be carefully evaluated and sometimes data are not available to ascertain the actual circumstances that caused death. How much time should a company get to do such an investigation before informing the public?
It does seem there are more fractures with the Sprint Fidelis than the earlier Sprint Quattro leads. But, according to Medtronic's 2007 Product Performance Report, the Quattro lead was also subject to fractures on occasion. So what number of lead fractures is tolerable? Zero of 126,400? One in 126,400? Twenty in 126,400? Two hundred in 126,400? When should the public be notified?
And if the leads fracture, don't we want to know why? What component was failing? What action is needed to correct the problem? Was the engineering of the lead responsible for the defect or the implant physician's technique? Does it matter? How long should a company be permitted to attempt to identify the root cause for a defect before the public is notified - 24 hours? A week? A month? 6 months? Should Medtronic have notified physician's first or the patients? Should Medtronic have notified the doctors before having an action plan established and a website developed to accompany the calls and questions?
These are all difficult questions to answer.
The Heart Rhythm Society has developed guidelines which begin to address and underscore the importance of many of these issues. Many of the actions taken with this recall have been in line with the initial draft of these proposals. Certainly, the information provided immediately to patients and physicians is much better with this recall than that we experienced in 2005 with earlier defibrillator recalls, but the challenges regarding patient notification and dealing with the clinical issues at hand remain.
I believe that the investigations ongoing and questions being asked are appropriate and worthwhile. The legal actions, too, may serve as an impetus for improvement of ICD systems. But in all of these dealings it is helpful to realize the complexity of the issues being discussed, and that in the end, it's the patients' interests that should matter most. After all, they're the ones dealing with the fallout.
-Wes
(WSJ) In early signs of the pressure likely to come for Medtronic and the FDA, (Senator) Mr. (Chuck) Grassley, a Republican, last night sent letters to the company and the agency asking for more information about the leads. Separately, consumer group Public Citizen argued in a letter that the company and agency should have taken action sooner.Now, looking back, things seem so obvious, don't they? It's all so easy, to detect these trends of lead fracture, isn't it? Well, maybe.
In addition, a group of plaintiffs attorneys, which has been a leader in major heart-device lawsuits, filed suits against Medtronic related to the Sprint Fidelis leads in federal court in Minneapolis and Puerto Rico, according to Hunter Shkolnik, one of the lawyers.
The investigations are likely to again focus attention on the FDA's oversight of medical devices, which are regulated under different standards than drugs. For instance, the Sprint Fidelis leads, which went on the U.S. market in 2004, weren't required to be tested in humans before they won FDA approval. Previous versions were tested in humans, but the Sprint Fidelis models weren't different enough from those earlier iterations to require human trials, the FDA said.
Then again, maybe not.
I thought it would be informative to check the FDA's MAUDE database for Medtronic's "safe" Sprint Quattro leads, and check on the number of deaths with that lead since 1/2005. And you know what? There are four deaths not related to infection. Hmm. 4 of 126,400 implants of Quattro leads (1 in 31,600) verses five of 268,000 implants of the "faulty" Sprint Fidelis (1 in 53,600). These data seem to support the Sprint Fidelis as less lethal than the Quattro. Could this be true? Admittedly, the FDA's MAUDE database is not the best place to evaluate such occurrences, but the point remains: verifying if the cause of death in an individual patient was actually caused by the lead itself is difficult - the circumstances of each death must be carefully evaluated and sometimes data are not available to ascertain the actual circumstances that caused death. How much time should a company get to do such an investigation before informing the public?
It does seem there are more fractures with the Sprint Fidelis than the earlier Sprint Quattro leads. But, according to Medtronic's 2007 Product Performance Report, the Quattro lead was also subject to fractures on occasion. So what number of lead fractures is tolerable? Zero of 126,400? One in 126,400? Twenty in 126,400? Two hundred in 126,400? When should the public be notified?
And if the leads fracture, don't we want to know why? What component was failing? What action is needed to correct the problem? Was the engineering of the lead responsible for the defect or the implant physician's technique? Does it matter? How long should a company be permitted to attempt to identify the root cause for a defect before the public is notified - 24 hours? A week? A month? 6 months? Should Medtronic have notified physician's first or the patients? Should Medtronic have notified the doctors before having an action plan established and a website developed to accompany the calls and questions?
These are all difficult questions to answer.
The Heart Rhythm Society has developed guidelines which begin to address and underscore the importance of many of these issues. Many of the actions taken with this recall have been in line with the initial draft of these proposals. Certainly, the information provided immediately to patients and physicians is much better with this recall than that we experienced in 2005 with earlier defibrillator recalls, but the challenges regarding patient notification and dealing with the clinical issues at hand remain.
I believe that the investigations ongoing and questions being asked are appropriate and worthwhile. The legal actions, too, may serve as an impetus for improvement of ICD systems. But in all of these dealings it is helpful to realize the complexity of the issues being discussed, and that in the end, it's the patients' interests that should matter most. After all, they're the ones dealing with the fallout.
-Wes
Tuesday, October 16, 2007
If It Ain't Broke, Don't Fix It
Reiterating most electrophysiologists' recommendations regarding Medtronic's Sprint Fidelis recall from the market, Tom Burton from the Wall Street Journal reports this morning:
Should a lead become fractured and the defibrillator system require revision, however, one other option exists that was not mentioned in the WSJ article: a new lead (or even a new system), could be implanted from the contralateral (opposite) arm. In some cases of lead fracture, this might be the safest route to take.
-Wes
Perhaps most important, Medtronic isn't recommending that the leads be taken out unless they are actually fractured. And cardiologists overwhelmingly agree with that advice. Surgical removal of a lead is potentially deadly itself. The lead sits in the patient's vein. Scar tissue forms there and at the point in the heart where the lead attaches. So extracting it can trigger bleeding, which can be lethal.What most agree, again, is that if a patient does not have an actual fracture, that leaving the lead alone is probably the most prudent advice and to continue close monitoring. Every time a device pocket is opened to revise the system, there is also a small but real risk of infecting the defibrillator system.
If a lead is found to be fractured, patients may have a choice of intervention. Doctors differ as to whether lead extraction or adding a new lead threaded through the same vein is a better approach. But many patients will have to have it extracted because there isn't room for a new lead in the vein.
Should a lead become fractured and the defibrillator system require revision, however, one other option exists that was not mentioned in the WSJ article: a new lead (or even a new system), could be implanted from the contralateral (opposite) arm. In some cases of lead fracture, this might be the safest route to take.
-Wes
Monday, October 15, 2007
More on Medtronic's Sprint Fidelis Advisory
With the issuance of the Medtronic's Sprint Fidelis lead advisory (on defibrillator lead models 6930, 6931, 6948, 6949) issued today, our office has already received over 50 calls with excellent questions. Understandably, people are concerned, so I thought I would take a moment to review the issues of the recall and answer a few of the more common questions.
Why would Medtronic have tried to design a thinner (6.6 Fr) lead, when their larger lead already had a fairly good track record for performance?
With the advent of biventricular defibrillators, that require three leads (one for the atrium, one for the right ventricle and one for the left ventricle), there is limited space in the subclavian and axillary vein. With the additional lead requirement of biventricular pacing, it was hoped that the smaller lead size would permit fewer vascular complications.
Why did Medtronic decide to voluntarily withdraw the Sprint Fidelis leads from the market?
There had already been a recognition my Medtronic and others that the lead may have a higher failure rate than prior lead models. An article in the journal Heart Rhythm also noted a higher-than-expected early fracture rate for this lead, but initial failures appeared clustered in certain centers. Hence, it was uncertain whether the failures were from implant technical issues or the lead design itself. Upon review of Medtronic’s ongoing quality review at their 30-month assessment, they felt the 2.3% failure rate sufficiently exceeded the complication rate of former leads (<1% failure rate) and decided to withdraw the lead, even though the fracture rate had not yet reached statistical significance. The trend, it seemed, suggested it would eventually reach significance.
What kind of problems can arise as a result of a lead malfunction?
The Sprint Fidelis lead contains four wires. Two of these wires are used for the rate sensing and pacing function of the lead, while the other two high-voltage wires are used for the shock-delivery function of the defibrillator system. If a fracture of one of the pacing/sensing leads were to fracture, typically noise is detected by the device as the wires rub together, and this might be interpreted by the device as an abnormal heart rhythm which, if it occurs long enough, could cause the device to deliver an inappropriate shock. Alternatively, a fractured pace/sense lead could lead to failure of the device to effectively pace the heart. If a shocking coil were fractured, while it might not effect the pacing or sensing feature of the device, it could lead to ineffective shock delivery during rapid heart rhythms, leading to ineffective termination of the arrhythmia.
Have deaths occurred from the lead malfunction?
Five deaths have been reported on the FDA's Maude database that are not related to infection of the device and may have been attributable to lead malfunction. Several instances of device undersensing of arrhythmias have been reported to the FDA database, and at least one episode of recurent shocks that may have contributed to death, but the details of these deaths have been limited.
I have a Sprint Fidelis lead. Should I have it replaced?
It is important to remember that a very small number of complications of this lead have occurred. The total complication rate with this lead was been 2.3% of the implanted devices to date. 97.7% of the leads implanted are performing correctly at this time. Because removal of the lead has a relatively high 1.4-7.3% mortality risk associated with their removal, it is generally not recommended these leads be removed at this time. If a lead fracture should occur, then placement of a new lead adjacent to the existing lead and leaving the old lead in place is usually recommended rather than extraction of the old lead with new lead implantation. Certainly, there may be circumstances where lead extraction is required, but these should be reviewed with your doctor.
Additional surveillance will be required to see how the remaining leads perform in the future. For now, most of us are recommending that the Patient Alert features on a patient’s defibrillator system be programmed to make them more sensitive to changes in lead impedance (a resistance measurement that might precede lead failure). Patients should make the appointments with their device clinic. The urgency of this reprogramming is generally up to the patient, but should probably be performed within the next 30-60 days.
Additional physician information, including parameters for programming the patient alert features can be found at http://www.medtronic.com/fidelis/physician-letter.html.
Information from Medtronic Regarding the Fidelis Advisory can be found at http://www.medtronic.com/fidelis.
-Wes
New York Times article on the lead advisory.
Why would Medtronic have tried to design a thinner (6.6 Fr) lead, when their larger lead already had a fairly good track record for performance?
With the advent of biventricular defibrillators, that require three leads (one for the atrium, one for the right ventricle and one for the left ventricle), there is limited space in the subclavian and axillary vein. With the additional lead requirement of biventricular pacing, it was hoped that the smaller lead size would permit fewer vascular complications.
Why did Medtronic decide to voluntarily withdraw the Sprint Fidelis leads from the market?
There had already been a recognition my Medtronic and others that the lead may have a higher failure rate than prior lead models. An article in the journal Heart Rhythm also noted a higher-than-expected early fracture rate for this lead, but initial failures appeared clustered in certain centers. Hence, it was uncertain whether the failures were from implant technical issues or the lead design itself. Upon review of Medtronic’s ongoing quality review at their 30-month assessment, they felt the 2.3% failure rate sufficiently exceeded the complication rate of former leads (<1% failure rate) and decided to withdraw the lead, even though the fracture rate had not yet reached statistical significance. The trend, it seemed, suggested it would eventually reach significance.
What kind of problems can arise as a result of a lead malfunction?
The Sprint Fidelis lead contains four wires. Two of these wires are used for the rate sensing and pacing function of the lead, while the other two high-voltage wires are used for the shock-delivery function of the defibrillator system. If a fracture of one of the pacing/sensing leads were to fracture, typically noise is detected by the device as the wires rub together, and this might be interpreted by the device as an abnormal heart rhythm which, if it occurs long enough, could cause the device to deliver an inappropriate shock. Alternatively, a fractured pace/sense lead could lead to failure of the device to effectively pace the heart. If a shocking coil were fractured, while it might not effect the pacing or sensing feature of the device, it could lead to ineffective shock delivery during rapid heart rhythms, leading to ineffective termination of the arrhythmia.
Have deaths occurred from the lead malfunction?
Five deaths have been reported on the FDA's Maude database that are not related to infection of the device and may have been attributable to lead malfunction. Several instances of device undersensing of arrhythmias have been reported to the FDA database, and at least one episode of recurent shocks that may have contributed to death, but the details of these deaths have been limited.
I have a Sprint Fidelis lead. Should I have it replaced?
It is important to remember that a very small number of complications of this lead have occurred. The total complication rate with this lead was been 2.3% of the implanted devices to date. 97.7% of the leads implanted are performing correctly at this time. Because removal of the lead has a relatively high 1.4-7.3% mortality risk associated with their removal, it is generally not recommended these leads be removed at this time. If a lead fracture should occur, then placement of a new lead adjacent to the existing lead and leaving the old lead in place is usually recommended rather than extraction of the old lead with new lead implantation. Certainly, there may be circumstances where lead extraction is required, but these should be reviewed with your doctor.
Additional surveillance will be required to see how the remaining leads perform in the future. For now, most of us are recommending that the Patient Alert features on a patient’s defibrillator system be programmed to make them more sensitive to changes in lead impedance (a resistance measurement that might precede lead failure). Patients should make the appointments with their device clinic. The urgency of this reprogramming is generally up to the patient, but should probably be performed within the next 30-60 days.
Additional physician information, including parameters for programming the patient alert features can be found at http://www.medtronic.com/fidelis/physician-letter.html.
Information from Medtronic Regarding the Fidelis Advisory can be found at http://www.medtronic.com/fidelis.
-Wes
New York Times article on the lead advisory.
Subscribe to:
Comments (Atom)