Tag: aortic surgery

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AAA EVAR open aneurysm surgery

Abdominal Aortic Aneurysm in Remission

Look again, it is a doodle of a CT scan of a patient with an Ancure stent graft with sac shrinkage

I remember in the mid-2000’s, driving very fast to Lutheran Hospital in Des Moines on a Saturday night to fix an aneurysm that had ruptured. He was a man over 70 years of age with a type III endoleak from a component separation. The endografts had been placed by a cardiac surgeon who had taken some courses. I rescued him by open replacement of the aneurysm with a tube graft after I pulled out the endografts. Later, as the patient recovered, I asked him why he never followed up as required on his stent graft. His answer was, in typical Iowa farmer fashion, “Welp. If it was fixed, why should I?”

Indeed, why should he? Looking at his chart from the time of his EVAR, he was determined to be a “high risk” patient, necessitating the new minimally invasive procedure EVAR in 2003. Seeing that he survived the stress test of a ruptured aneurysm, it was clear he was not all that “high risk.” I did reassure him that with the open repair, he was basically cured. Despite scheduling a followup appointment, he never showed up. And that was okay.

EVAR is a treatment for AAA, but currently not a cure. All of the devices instructions for use stipulate the need for lifelong followup with CT scans with contrast and visits with qualified specialists. As I have mentioned in the past, what other condition requires surveillance CT scans with contrast and followup with a specialist? Cancer in remission. For those with good cardiac risk and functional status, placing an endograft rather than open repair creates “Aortic Aneurysm in Remission.” If they are in the majority of patients with a stable aneurysm sac, their endografts are sitting in a bag of static, aging blood. If there are type II endoleaks, and it is my belief that the majority of stable aneurysm sacs have some type II endoleaks that blinker on and off depending on the hemodynamics, particularly through needle holes, they are circulating the products of breakdown of that bag of old blood and exposing a perfect culture medium to potential inoculation. These type II and IV endoleaks can inflate the aortic sac over time. Occasionally, the residual AAA sacs rupture, erasing any of the early advantage conferred by the minimally invasive index procedure in long term followup EVAR v OPEN repair.

What is a cure? A cure is when you quell an infection with an antibiotic. A cure is when you’ve taken out an inflamed appendix. It’s when you’ve eradicated early stage cancer. It’s when you perform an open aortic graft and the patient can disappear after you remove the dressings and never followup, sure in the knowledge that the aneurysm in that spot will never bother them again. With EVAR, only a minority get to the state (figure at top) a sac shrunk intimately around the endograft. Most are not cured but enrolled in a regime of lifelong surveillance and maintenance.

EVAR does allow people to leave the hospital with less scarring and pain, but the consequences of its popularity are:   

1. Letting more practitioners, not all of them vascular surgeons, treat aortic aneurysm disease with less training and with less or no ability to manage the inevitable failures surgically. 

2. Creating the business model for “Advanced, Minimally Invasive, Super-Fantastic Aortic Centers of Excellence” which is predicated on the business of surveillance and maintenance of aortic endografts. It is a busy-ness that generates revenue, but burdens the country with more healthcare costs. It ultimately siphons business away from true centers of excellence involved in training the next generation of vascular surgeons.

3. Skewing the training curriculum of trainees to endovascular so much that I have met vascular surgeons who have done no aortic operations. That was the case when I sat in on an open aortic surgery class at the 2017 ESVS meeting in Lyons, France. All the attendees were very eager to try sewing anastomoses, but felt they needed proctoring which isn’t available.

4. Establishing the expectation that open aortic surgery is a failed, antiquarian, obsolete technique to be relegated to the history books. This last one is infuriating and not true but it is out there in the claims of the aorticians.

5. Resulting in palliation when the aortic aneurysm in remission ruptures and there are no readily available open-capable surgeons experienced in rescuing these patients. This happens. Don’t let it happen to you.

Various solutions have been broached including regionalization of aortic aneurysm care, superfellowships in exovascular surgery to complement the widespread endovascular training, and going back to open aortic surgery as the norm as had been proposed controversially in the UK. There is no turning back the clock. The moment that Dr. Parodi combined an aortic graft with Dr. Palmaz’s stent, a quantum leap occurred. The operation of aortic aneurysm surgery was changed from a challenging operation mastered by a few to a straightforward procedure performed by many.

Interesting to me is that illustration at the top of the post is of a common observation – the obliteration of the aortic aneurysm sac around a Guidant Ancure stent graft. When the sac disappears, it is as close to a cure that you can get. For some reason, I see this more frequently with Ancure than with other grafts over the past twenty years.

Odd fact -I may have been the last surgeon to implant an Ancure in the world. In 2003, I was treating a AAA with an Ancure graft when the delivery system froze in mid deployment. I called Dr. Dan Clair away from some meeting, and he called for pliers, screw drivers, and a saw, and after deconstructing the delivery system, deployed the graft and returned to his meeting with nary a word. The Guidant rep, who had been on the phone, looked up with saucer eyes, and said, “Wow. They’ve pulled Ancure off the market.”

I think it is because of the design, which is now off the market. When stents are sewn to cloth, the needle holes leak, and leak particularly where the stent graft makes a turn, stretching the suture hole. Junctions and seams leak. The Ancure, aside from the stents at top and bottom in the seal zone, has no such holes as it is unsupported and manufactured as a single piece with no junctions or seams. It is the closest you get to sewing in a graft by open surgery. If it weren’t for its overly complicated delivery system which was its downfall, I think it would be in its third generation with visceral branches that are created off the textile machines rather than joined inside the patient. There are lessons to be learned from this abandoned tech.

I believe a treat once and walk-away cure is achievable in EVAR. The idea is not to be satisfied with anything less than a cure, anything that ends with aortic aneurysm in remission. We have to understand we have chosen a path of iteration and continuous but slow improvement in the EVAR space. The front end benefits of EVAR are clear but it is in the long term we have to focus. Until then, warranties would be great.

Categories
acute mesenteric ischemia aortic dissection bypass chronic mesenteric ischemia complications ruptured AAA taaa tbad techniques TEVAR thoracabdominal aortic aneurysm training type b aortic dissection visceral malperfusion

Life imitates social media: a ruptured type V thoracoabdominal aortic aneurysm or IT saves a life

ARTERIAL (2) (2)
Type V TAAA Rupturing into Right Pleural Cavity

It was only last month when I came across a post of an aortic aneurysm in a difficult spot (link) and I couldn’t help chiming in some comments. Reading it now, I sound insufferable, because I wrote,

“Depends on etiology and patient risk stratification. Also assuming aneurysm goes to level of SMA and right renal artery origins and involves side opposite celiac. Options depending on resources of your institute: 1.Open repair with cannulation for left heart bypass and/or circulatory arrest 2.Open debranching of common hepatic, SMA, R. Renal from infrarenal inflow and then TEVAR 3.FEVAR from custom graft from manufacturer on protocol 4.Parallel grafting to CA, SMA, R. RA with TEVAR 5.Surgeon modified FEVAR 6.Open Repair We would have a multidisciplinary huddle around this patient -Vascular, Cardiac Surgery, Cardiology, Anesthesia, and ID (if needed) to help choose. Be ready to refer to a center with more resources -including prepping patient for transfer and imaging -including uploading images to the cloud for transfer with patient’s permission. More info please”

More Info Please, Indeed

The post I commented on was of a saccular aneurysm in the transdiagphragmatic segment of aorta. Ironically, only a few weeks later, I got called from hospital transfer center about a patient with a leaking aortic aneurysm, a type V thoracoabdominal aortic aneurysm as it turned out, from an outside hospital, needing urgent attention, and we accepted in transfer based on the conversation I had with the tranferring physician. And that was the problem -usually in taking these inter-hospital transfers, you have to pray that the precious CT scans come along with the patient burned correctly onto a CD-ROM. You can buy and watch a movie in 4K resolution over the internet -about 4 gigabytes, but a patient’s CT scan which is about 200 megabytes -because of various self imposed limits, overly restrictive interpretations of laws, and lack of computer skills, these life saving images get transferred on CD in 2019. That last time I purchased a CD for anything was over 15 years ago.

An Interested Party

The technical solution –to use the internet to transfer critical life saving information between hospitals – came about when our IT folks took an interest in my quarterly complaint email about using the newfangled internet for sharing files. After mulling various solutions ranging from setting up a server to using commercial cloud solutoins, we came upon the compromise of using our internal cloud with an invitation sent to the outside hospital. I would send this invitation to upload the DICOM folder of the CD-ROM to an outisde email address. It was simple and as yet untried until this night. “Would the patient agree to have his CT scan information transmitted to us electronically?” I asked the other physician. He assured me that the patient was in agreement.

It Takes Two to Tango

Of course, being able to transfer these pictures requires a willing partner on the other side, and the referring physician made it clear he did not have the technical expertise to do so. It took a bit of social engineering to think about who would have that ability. Basically, aside from myself, who spend all their time in dark rooms in the hospital in front of giant computer monitors? The radiologists! I got through to the radiologist who had interpreted the report and explained the simple thing I needed. Gratefully, he agreed, and I sent him a link to our cloud server. I explained to him, “When you receive this, clicking the link opens a browser window and then you open the CD-ROM and find the DICOM folder and drag and drop it on the browser window.” The 200-500 megabytes of data then get sent in electronic form, as it was meant to in 2019.

The Internet Saves a Life

The brutal truth is that in locking down a computer system, many hospitals make it impossible to even load an outside CD-ROM, creating many self imposed barriers to care. Thankfully, at CCAD, we were able to work together to find a secure solution. With the CTA on our servers, I was able to review the study within 15 minutes of accepting the patient, and arrange for the right team to be assembled, and confirm that we had the right material (stent grafts) for treating the patient. When the patient arrived, OR was ready to go, saving hours of time that normally would have been required if the CT scan had to be reviewed from the CD-ROM that came with the patient. Sometimes, the CD-ROM does not come, and in a critical situation, the CTA has to be repeated with some risk to the patient for complications of the contrast and radiation.

What to Do

The patient had a 8cm sphere shaped aneurysm arising in the transdiagphragmatic aorta, leaking into the right pleural cavity.

Screen Shot 2019-06-19 at 9.29.15 PM

The patient was otherwise a healthy middle aged man with risk factors of smoking and hypertension. The centerline reconstructions showed the thoracic aorta above the aneurysm to be around 20mm in diameter and same below, with the celiac axis and superior mesenteric artery in the potential seal zone of a stent graft. The only plaque seen was around the level of the renal arteries and was focal and calcified. Looking at the list I had made as a comment to the Linked-In post, I realized that I really only had one viable option.

ARTERIAL (10).jpeg

Open repair, usually the most expeditious option, was made challenging by the right hemothorax, making a left thoracotomy hazardous if the lung had to be deflated. Cardiopulmonary bypass would have to be arranged for, and that adds a metabolic hit that greatly raises the stakes. Of the endovascular solutions, the only viable option was TEVAR to exclude the rupture and debranching of the celiac axis and superior mesenteric artery. To those who would advocate for parallel grafts, there was no room in the normal 20mm diameter aorta. And branch systems for rupture are some time in the future. Also, the patient was becoming hypotensive. So the planned operation was first TEVAR to stop the bleeding, and then open surgical debranching. A hybrid repair.

plan sketch.PNG

The smallest stent graft we have is a 21mm graft, but it would not be suitable for this aorta. In practice, the normal aorta is quite elastic and will dilate much more than what is captured on a CTA. The next size we have is 28mm graft and I chose this to exclude the rupture, which was done percutaneously.

TEVAR angio.png

As seen below, the graft excluded the celiac and SMA. Late in the phase of the final aortogram (second panel) there was an endoleak that persisteed despite multiple ballooning. The timing suggested the intercostals and phrenic vessels contributed to a type II endoleak, but it was concerning.

postangio.png
Find the Endoleak

The bypasses were sent from the infrarenal aorta to the common hepatic artery and the SMA close to its origin, and the origins of the celiac axis and SMA were clipped. The bypasses were then done with a 10x8mm bifurcate Dacron graft originally for axillofemoral bypassing. It had spiral rings which I removed at the anastomosis and this resulted in a kink at the closer bypass. Usually, I loop this for iliomesenteric bypass but there was not enough distance from the infrarenal aorta. I have to add a little trick I modified from my pediatric surgery experience as a resident -a Heinecke-Mikulwicz graftoplasty:

IMG_2646.JPG

This worked to relieve the kink as evidenced on the aortogram above. After closing the laparotomy, I placed a chest tube in the right chest. The patient had a course prolonged by a classic systemic inflammatory response syndrome, with fevers, chills, and leukocytosis. He bled for a while but stopped with correction of his coagulopathy. All blood cultures were negative, but a CT scan was performed out of concern for the endoleak, and the possibility of continued bleeding.

postCTA.jpg

No endoleak was detected as the sac was fully thrombosed. There was a consolidation of the blood in the right chest, but it resolved with fibrinolytic therapy.

Discussion

This case illustrates several points I have been making on this blog.

  1. Hybrid repairs are not some kind of compromise but the full realization of a complete skill set. When students ask me how to judge a training program, one of the best metrics is how frequently are hybrid operations performed. It means either the endovascularist and open surgical operator are in complete synchrony or there are individual surgeons competent in both open and endovascular surgery. Hybrid operations, rather than being a compromise, are an optimization.
  2. Time -Laying the stent graft across the celiac and SMA origins starts a warm ischemia clock. The liver and intestines, in my reckoning, should be able to tolerate the 2 hours of work to get the bypasses working. Cardiopulmonary bypass may give you less ichemia but at the metabolic cost of the pump time. These negative factors add up, but were surmounted by the fact that early control of hemorrhage was achieved. Stopping the bleeding and restoring flow are the core functions of vascular surgery.
  3. Planning and preparation. The ability to see the CT images and prepare the teams and materiel before the patient transferred was lifesaving. This is where our IT gets credit for responding to a critical need and formulating a solution that meets internal policies, external regulations, and saves a life. It illustrates so many opportunities particularly with electronic medical records and their processes which focus more on documentation for billing. A discharge summary should be multimedia like this blog post and it should be normal and easy to generate. And finally, as clinicians, we should mind technology with as much attention as we give to the latest medical devices and techniques.
Categories
AIOD aortoiliac occlusive disease (AIOD) bypass CTA pheocromacytoma

Incidental Pheochromacytoma

An oldie but a goodie from my first blog, “The Pipes Are Calling” on Medscape. This case came to mind when I recently diagnosed a pheochromacytoma from my clinic -middle aged man with difficult to control hypertension and unilateral renal artery stenosis. One of the most critical lessons learned from medical school, the Columbia University College of Physicians and Surgeons, was to be a complete physician, to be curious and engaged in the well being of your patient even outside the narrow focus of your specialty. This I learned especially from people like Drs. Harold Neu and Mark Hardy.

Incidental Pheochromacytoma

W. Michael Park, MD, Surgery, Vascular, 05:24PM Jun 23, 2010

The patient is a middle aged man who developed rest pain of his left leg after CABG for 3VCAD/MI. Workup revealed an occluded left iliac arterial system with diffuse atherosclerosis of his aorta and iliac arteries. He had a long history of bilateral calf claudication and his right SFA was occluded and his left SFA was diffusely diseased. CTA was performed and showed the described anatomy

And a “2.2cm peripherally enhancing mass” probably representing a lymph node with central necrosis, adjacent to the aorta.

I proceeded with aorto-right iliac and left femoral bypass, planning on later leg revascularization as needed after establishing inflow. During the retroperitoneal dissection over the aorta, I ran into this purplish mass and on manipulation, the patient’s blood pressure shot to 210mmHg. As my brain processed, my resident who had just finished reading his chapter on endocrine, said, “this could be a pheochromocytoma.”

That tumor was out quicker than you could say “snit.” Frozen section, and later final pathology returned paraganglionoma.

The patient recovered well and graciously gave permission, as all my patients here do, to allow this to be discussed. He noted that hypertension kept him out of Vietnam. Records showed an uneventful CABG.

Applying the retrospectocsope, I will now be far more wary of midline retroperitoneal lesions that are highly vascularizad.