Vascular Device Forum

Bart Muhs MD- EVAR technologies Today and Beyond

Dr Bart Muhs, Assistant Professor of Vascular Surgery and Co Director of Endovascular Surgery at Yale University School of Medicine, offered some exclusive insights to VascularDeviceForum.com. Dr Muhs was trained at New York University School of Medicine as a general surgeon and vascular fellow. He subsequently completed a PHD at Utrecht University. EVAR development is lead by an outstanding line up of US trained physicians(many of them surgeons I might proudly add) , including Tim Chuter MD who have broadened their exposure in EVAR space with post doc experiences in the fertile and less regulated landscape of the European medical environment. I do think that these doctors represent the new paradigm shift of physician specialization that is not limited by historic definitions of scope of practice as you may notice from Dr. Muhs academic title in the dept of radiology. Dr Muhs is one of the thought leaders for the field of EVAR assisting in creating a vision for sound research driven innovation that leads to clinically relevant aortic stent graft design.

Some of his current investigational work includes:

Abdominal aortic aneurysm – PYTHAGORAS Study. This study evaluates a new endovascular aortic stentgraft to treat abdominal aortic aneurysm in patients who would otherwise require an open surgery.

Thoracic aortic dissection – This study evaluates the use or thoracic stentgrafts to repair acute aortic dissections or tears that can occur in the descending thoracic aorta.

Abdominal aortic aneurysm – This trial uses magnetic resonance imaging to evaluate the effect of placing aortic stentgrafts for the treatment of abdominal aortic aneurysms. Information from this trial will allow for the design and development of improved stentgrafts with better patient outcomes.

Abdominal aortic aneurysm – This institutional study evaluates prognostic factors that can be used to improve patient outcomes following open and endovascular abdominal aortic aneurysm repair.

This is the first of a two part posting from this informative conversation. The prevailing theme in the conversation is that future advances in EVAR will likely be dictated by a greater appreciation for the physiologic differences that distinguish the aneurysmal disease, dissections and traumatic aortic injuries. As well as the age related physiologic differences in these respective pathologies. Aneurysm physiology and biochemistry will ultimately influence stent graft engineerying and design.

Dr Muhs is using EKG-gated phase contrast imaging of the aorta using MRI technology. Using 2mm windows, compliance is being measured in different areas of the aortic environment. Branch segments, angulated segments, posterior wall versus the anterior aneurysm wall. These parameters can be assessed in different aneuryms morphologies, age groups. The study is sponsored by the American Geriatric Society. This study hopes to provide insight into predicting aneurysm behavior based upon this PhaseContrast MRI. Currently the study has accumulated data on normal and healthy volunteers.

Next, we focused on three distinct areas of aortic pathology:

1)Trauma

2) Dissection

3) AAA

I received quite a few questions leading up to the Dr Muhs interview regarding the use of EVAR in repair of traumatic aortic tears. This group represents the potential for significantly improved outcomes with EVAR technology. Frequently, this blunt trauma pathology is associated with other injuries like pelvic injury and intra abdominal visceral injury. Significantly, increasing the trauma score. In this setting, minimally invasive prompt means to treat this aortic injury is potentially life saving, avoiding the need for open thoracic repair.

Dr Muhs work is particularly important in this context as it should reveal the clinically significant physiologic features that characterize the young person's aorta. Dr Muhs elaborated further: Anatomically, these patients have acutely angulated thoracic arches which are highly compliant. In his experience, one pearl involved in the preparation process is the aortic diameters measured by CT scanning in the hypovolemic, compliant aorta. He described an early patient or two that would undergo successful repair acutely only to have a type I leak on follow up. He recommends approximately 30% oversizing to address this concern.

Additionally, his prediction is that future research will demonstrate that many of these patients have completely healed their injury at 12 months or so. Raising the theoretical consideration that a bio absorbable device would obviate the need for a 20 or 30 year old person to have a current devicetype in place for the rest of their life. Ie a bio absorbable aortic stent graft. More to follow in the next post including our discussion about aortic dissections, the new frontier application for stent graft technology and our evolving understanding Please share your ideas about these innovative EVAR ideas

Diamondback from CSI-Niche useless device or Toolbox Asset

For those of you who have entered the world of athrectomy/atherectomy you might be following the trajectory of CSI(Cardiovascular Systems Inc) which was ramping up to conduct an IPO. Information surfaced in early November 2008 that due to the challenging economic conditions and the IPO drought, they would merge with a struggling existing publicly traded company Replidyne. By reports, Replidyne is essentially a shell company with no products, no revenue and very few employees. What they do have is a Nasdaq listing and a ticker symbol.

Over the past few months, IPOs have ground to a halt, forcing companies to either postpone or pull their stock debuts altogether. In the first nine months of this year, 77 companies withdrew their IPOs, 19 in the third quarter alone, according to Bloomberg News. Through September, just 55 companies have gone public, down from 226 during the same period in 2007.

Getting creative

Im interested to get some feedback on this device. We know that the Silverhawk formerly of Foxhollow and now EV3 fame had limitations such as an inability to treat vessel calcification. The initial company push for the Diamondback is for the treatment of calcific athero-occlusive disease. I have successfully used it in densely calcified infra popliteal vessels. The question becomes, depending upon ones population, is the presence of segmentally, calcified infra pop disease so infrequent as to make the indicated use for this device relatively few and far between. I have used it on minimally calcified vessels with underwhelming results as one would expect  based upon its theoretical mechanism of action which is atherectomy of calcific, non compliant tissue.

The major cost associated with the device include multiple catheter sizes and a couple of different crown types for various disease levels. To date, my impression is that a lot of enthusiasm for this device is in the interventional cardiology space. I feel that durable results with minimally invasive technology is really limited to focal tibial level disease with good run off. Unfortunately, many of the diabetic and renal insufficiency patients with dense calcific vessel disease have an extremely diffuse pattern. And in the circumstance when there is significant tissue loss, I personally feel that direct pulsatile flow to the area of tissue loss is the most reliable means of salvaging the limb if adequate conduit is available. Furthermore, products like the propaten graft from Gore Medical and the Venaflo from CR Bard offer reasonable alternatives to spliced vein autologous vessel bypass.

Bottom line, is that I would like to get a some feedback on what others are experiencing in their practice with the use of this technology.

Sensei™ System from Hansen Medical

At the Veith Meeting in New York, I saw my former mentor and attending in general surgery, William H Hendren. He now is an active consultant for Hansen Medical. Professor Nick Chesire is their physician face and he presented a very interesting experience with this technology and its application in EVAR

The theoretical end point would be a proceduralist seated away from the patient, remotely performing the procedure with robotic assistance.

No More Device Reps in the OR, Cath lab?

Imagine that. No more product and device representatives in the IR suite, Cath Lab or OR? No more anxious, ambitious type A's with their company stock option portfolio feigning interest in a difficult case hoping quietly that the proceduralist calls for their device or product so that they can keep their regional supervisor off of their back for another fiscal quarter. OK, that's an exagerration but there is quite the perverse relationship in some setting where there are numerous products/devices available to procedurally treat the same disorder.

As the scrutiny of this relationship between industry, proceduralist and hospital/university increases, a proper balance will be necessary to avoid the extreme moratorium that will result when Congress begins to regulate the process. Currently, a number of orthopedic and cardiology physicians have been sent letters to describe their relationship with industry in various "consultant" arrangements. There is certainly more to come and the heat will be turned up on the process. Its emotionally compelling, the public loves to see the money grubbing professional exposed and to be truthful-the relationship really does need to be examined. Read one surgeons comments Source

Device Reps Should Limit Their Role In The Operating Room, Says Surgeon

Full article reprinted from "The Gray Sheet" - December 8, 2008

Find out how device company representatives have a legitimate role in the surgical suite, but many overstep, according to surgeons speaking at a meeting in Washington, D.C., Dec. 3.

Device Reps Should Limit Their Role In The Operating Room, Says Surgeon

Full article reprinted from "The Gray Sheet" - December 8, 2008

"It takes leadership to figure out how to work together, to have physicians, the hospital and the device company on the same page," said Kevin Bozic, University of California, San Francisco, at an ECRI Institute conference on value-based purchasing.

Bozic, a practicing orthopedic surgeon and chair of the Healthcare Technology Assessment Program at UCSF Medical Center, said device reps have two important roles within his OR: to help with inventory management and to provide technical assistance for the nursing staff.

"His role is not to upsell me on the technology," Bozic said, although he acknowledged that the problem "happens in orthopedics every day."

From the audience, another physician raised concerns about the "latest and greatest technology" being chosen for implants because a device rep pulls it out of the trunk, "as opposed to thoughtful consideration as to whether the patient should get the device."

Hospitals Push Back With Attempts To Deny Access

In extreme cases, device representatives can put patients, hospitals, physicians and employers at risk if unwarranted advice in the OR leads to poor patient outcomes.

Stories about such cases in the mainstream media have put pressure on stakeholders to reduce any appearance of conflict of interest or compromise in patient care.

Liability issues have led some hospitals to require vendor credentialing - covering anything from background checks to vaccinations - for device reps to gain access to facilities or physicians (¹"The Gray Sheet" March 24, 2008, p. 14.)

Bozic is concerned that hospital backlash against device reps can get heavy-handed.

"The relatively short-sighted response of most hospitals unfortunately has been to develop policies to try to keep these people out," said Bozic, who also serves on the board of the American Academy of Orthopaedic Surgeons.

"In my hospital, they wear red stripes; they look like prisoners."

In discussions with colleagues around the country, Bozic has heard others joke that "we make them stand out in the cold for an hour in the freezing cold in Chicago, and get a badge."

Manufacturer Focus Is On Training And Testing

Device maker Medtronic would be "happy not to have our reps in operating rooms," as long as hospital staff were well-trained in using the technology in the company's implantable devices, according to David Steinhaus, medical director and vice president for strategy and professional relations for the firm's cardiac rhythm disease management division.

When it comes to complex devices such as implantable cardioverter defibrillators, "our devices have to be tested in the operating room," Steinhaus said. He said that especially for cardiac devices, Medtronic's reps are "highly trained."

Training hospital personnel becomes more of a challenge when nurses support multiple doctors who choose a variety of devices from multiple vendors.

"If you are doing surgeries in an operating room and you have different surgeons doing different implants, it's hard to train nurses to understand how to do this, which makes us more dependent on the role of the rep," said Bozic. "And there is a lot of inventory management. It is a huge problem."

A private payer attending the conference said hospitals and industry should not consider the issue of device reps in the OR an "all or none" proposition.

She added that insurers are interested in understanding more about the kinds of incentives device reps receive from their employers for their work within the operating room.

- Monica Hogan

Share your comments about the role of the device rep and regulation/oversite

Full article reprinted from "The Gray Sheet" - December 8, 2008

Find out how device company representatives have a legitimate role in the surgical suite, but many overstep, according to surgeons speaking at a meeting in Washington, D.C., Dec. 3.

Device Reps Should Limit Their Role In The Operating Room, Says Surgeon

Full article reprinted from "The Gray Sheet" - December 8, 2008

"It takes leadership to figure out how to work together, to have physicians, the hospital and the device company on the same page," said Kevin Bozic, University of California, San Francisco, at an ECRI Institute conference on value-based purchasing.

Bozic, a practicing orthopedic surgeon and chair of the Healthcare Technology Assessment Program at UCSF Medical Center, said device reps have two important roles within his OR: to help with inventory management and to provide technical assistance for the nursing staff.

"His role is not to upsell me on the technology," Bozic said, although he acknowledged that the problem "happens in orthopedics every day."

From the audience, another physician raised concerns about the "latest and greatest technology" being chosen for implants because a device rep pulls it out of the trunk, "as opposed to thoughtful consideration as to whether the patient should get the device."

Hospitals Push Back With Attempts To Deny Access

In extreme cases, device representatives can put patients, hospitals, physicians and employers at risk if unwarranted advice in the OR leads to poor patient outcomes.

Stories about such cases in the mainstream media have put pressure on stakeholders to reduce any appearance of conflict of interest or compromise in patient care.

Liability issues have led some hospitals to require vendor credentialing - covering anything from background checks to vaccinations - for device reps to gain access to facilities or physicians (¹"The Gray Sheet" March 24, 2008, p. 14.)

Bozic is concerned that hospital backlash against device reps can get heavy-handed.

"The relatively short-sighted response of most hospitals unfortunately has been to develop policies to try to keep these people out," said Bozic, who also serves on the board of the American Academy of Orthopaedic Surgeons.

"In my hospital, they wear red stripes; they look like prisoners."

In discussions with colleagues around the country, Bozic has heard others joke that "we make them stand out in the cold for an hour in the freezing cold in Chicago, and get a badge."

Manufacturer Focus Is On Training And Testing

Device maker Medtronic would be "happy not to have our reps in operating rooms," as long as hospital staff were well-trained in using the technology in the company's implantable devices, according to David Steinhaus, medical director and vice president for strategy and professional relations for the firm's cardiac rhythm disease management division.

When it comes to complex devices such as implantable cardioverter defibrillators, "our devices have to be tested in the operating room," Steinhaus said. He said that especially for cardiac devices, Medtronic's reps are "highly trained."

Training hospital personnel becomes more of a challenge when nurses support multiple doctors who choose a variety of devices from multiple vendors.

"If you are doing surgeries in an operating room and you have different surgeons doing different implants, it's hard to train nurses to understand how to do this, which makes us more dependent on the role of the rep," said Bozic. "And there is a lot of inventory management. It is a huge problem."

A private payer attending the conference said hospitals and industry should not consider the issue of device reps in the OR an "all or none" proposition.

She added that insurers are interested in understanding more about the kinds of incentives device reps receive from their employers for their work within the operating room.

- Monica Hogan

Share your comments about the role of the device rep and regulation/oversite