Brian Lacy, MD, and David Tendler, MD, on Mesenteric Ischemia: Part 2

Dr Lacy and Tendler continue their conversation about the diagnosis and treatment of acute and chronic mesenteric ischemia. 

For Part 1 of this podcast, click here.

Brian Lacy, MD, is a professor of medicine at the Mayo Clinic in Jacksonville, Florida. David Tendler, MD, is a clinical associate at Duke University in Durham, North Carolina.

For more insights from experts like Dr Tendler, click here.

TRANSCRIPT:

Dr. Brian Lacy:  Welcome to this "Gastroenterology Learning Network" podcast. My name is Brian Lacy. I'm a professor of medicine at the Mayo Clinic in Jacksonville, Florida. I'm delighted to have Dr. David Tendler return today to finish our discussion on chronic mesenteric ischemia. As you may recall, Dr. David Tendler is clinical associate of medicine at Duke University in Durham, North Carolina.

We had a great first-part discussion on mesenteric ischemia, and we're having him return here today to finish that discussion. Dr. Tendler, welcome. Let's shift gears now and let's consider chronic mesenteric ischemia, which is a different beast in many ways. Is this more of a problem or less of a problem than acute mesenteric ischemia epidemiologically?

Dr. David Tendler:  Statistically, an elderly patient is much more likely to have chronic mesenteric ischemia than acute ischemia. This is analogous to coronary artery disease in that regard. It's just another form of vascular disease in a sense. It's not that uncommon in that population.

Up to 20 percent of elderly adults will be shown to have mesenteric vascular disease, although thankfully, it's relatively a small fraction that will have symptoms on account of that. Again, largely related to the effective collateral system, but it's a much more common problem in acute ischemia.

Dr. Lacy:  To clarify for our listeners, which populations are most at risk? Is it just the elderly or elderly and diabetics, or those with a history of a prior MI or CVA?

Dr. Tendler:  All the above. The risk factors for symptomatic disease generally include being over age 60. It is a little bit more female predominant. History of cigarette smoking, history of coronary artery disease or cerebrovascular disease, history of peripheral vascular disease, or those conditions that predispose to those things such as diabetes.

Dr. Lacy:  Once again, coming back to what you said earlier, taking that history, it just so critical. Thinking about the symptoms, sometimes these symptoms are a little bit different, and I bet sometimes they're overlooked. What do you think are the classic symptoms of chronic mesenteric ischemia we should identify?

Dr. Tendler:  Going back to those old textbooks, they still stand. The classic triad for chronic mesenteric ischemia includes progressive postprandial abdominal pain. Then, on account of that, patients will generally learn since food is causing their pain, they'll develop a food aversion or cibophobia. Then, because of that, they'll lose weight.

The classic triad is postprandial abdominal pain, food aversion, and weight loss. Also, the chronic diarrhea turns out to be a more common symptom than originally reported, but those are the main symptoms. It's very easy to overlook these symptoms, particularly given how common a symptom food-provoked pain is.

The alarm symptoms of developing a fear of eating in order to avoid pain as well as weight loss, that's when it should at least trigger a suspicion in the appropriate patient who may be at risk for vascular disease.

Dr. Lacy:  Wonderful. That older patient, pain with eating, losing weight, really think about chronic mesenteric ischemia. You've mentioned this early on, but it's worth emphasizing again pathophysiologically. How does this differ from acute mesenteric ischemia?

Dr. Tendler:  The pathophysiology is similar to acute thrombotic ischemia. In that, you have a high-grade stenosis of at least two mesenteric arteries. In fact, most cases of acute thrombotic ischemia, most of those patients, generally speaking, will have a history of having had chronic mesenteric ischemia symptoms that may have been indolent at first and then progressive.

Then, generally, you'll see a more subacute presentation before an acute thrombotic ischemia, so it's undiagnosed and chronic mesenteric ischemia is not on your radar. Then, eventually, that will and can progress to acute bowel ischemia and bowel infarction. Clearly, that's what we're trying to avoid.

Dr. Lacy:  David, let's say, we're sitting with a nice 74-year-old woman, ex-smoker, heart disease, TIA a couple of years ago, pain with eating, losing weight, and you're considering this diagnosis. Diagnostically, where do we start in the office that day? Maybe if even had a step-wise approach, a simple test, a more invasive test. How do you like to do this?

Dr. Tendler:  Short of CT or MR angiogram, you're probably circling your tail. There are institutions that have very good expertise with Doppler ultrasound, and there are some good studies out of those institutions showing a very high degree of sensitivity of picking up mesenteric ischemia with that.

However, generalizing to most of our institutions, CT angiography or MR angiography remains a standard diagnostic test of choice. Both have a very high sensitivity for diagnosing high-grade stenosis of the mesenteric arteries.

Dr. Lacy:  If you're not at a great center of excellence with a mesenteric duplex, maybe jump into the best diagnostic test and skip that unnecessary test.

Dr. Tendler:  I think so. Once that condition pops up on your radar, if you're thinking about it, at that point I think you really should. If there's a high enough index of suspicion, you should just go right to the test so going to answer that question.

Dr. Lacy:  Great. Treatment options, is this send them back to the primary care doctor and say, "Take care of the blood pressure and cholesterol issues?" Do you send them to the vascular surgeon? What else can we offer these patients?

Dr. Tendler:  It depends on whether they got asymptomatic vascular disease or whether they're symptomatic. For patients that may have incidentally discovered mesenteric vascular disease that are asymptomatic, conservative measures in that population are appropriate, and of course, monitoring. You don't want to pat him on the back and never see them again.

In terms of conservative measures, optimizing management of high blood pressure, lipid disorders, obesity, optimizing control diabetes, addressing smoking cessation, all of those things, we would consider conservative measures are appropriate in those patients as they would be for other patients with other forms of vascular disease.

Generally, unless it's otherwise contraindicated, antiplatelet therapy is a good idea if they're not on it already. For symptomatic patients, they need to be revascularized. We're trying to avoid a catastrophic outcome. Surgical or endovascular revascularization is important in that population.

That,again, maybe surgery, angioplasty stenting, which is chosen again, a lot of factors that come into that probably beyond the scope of this discussion. The patient characteristics and institutional expertise become important factors.

In my mind, the first issue is, are you discovering the mesenteric vascular disease incidentally asymptomatically, or are they symptomatic in which case you do need to pursue revascularization to avoid a bad outcome.

Dr. Lacy:  Again, pulling in that hematologist, pulling in that vascular surgery service, and doing this as a team effort. Wonderful. David, this really has been a wonderful [laughs] conversation. I learned an awful lot. I know our listeners have as well. Any last thoughts for our listeners?

Dr. Tendler:  I know I sound like a broken record, Brian, but the most important take-home point remains having these conditions on your clinical radar. A high index of suspicion will typically result in the right course of action, but none of that's going to happen if the diagnosis is never considered.

Despite advances in diagnostic imaging, despite advances in surgical technique, and endovascular therapies, none of those factors come close to affecting patient outcome relative to making a rapid diagnosis. While that's probably true for many things, it's so important for clinicians to evaluate pain in the context of this specific patient.

If the patient's presenting with pain, that's out of proportion to the physical exam. They're elderly, they may be at risk for vascular disease, or in the case of a younger patient, might have risk factors from thromboembolism, all that needs to be getting our mesenteric ischemia antennas up.

Dr. Lacy:  Wonderful. Great teaching points, especially for some of the clinicians and healthcare providers who maybe are a little bit earlier in their career. David, thank you so much. This has been just a wonderful conversation. I appreciate it. I know our listeners do.

For all of our listeners who are here today or another days, look forward to another podcast in the future on the GI Learning Network. Thank you so much.

Dr. Tendler:  Thank you for having me.