Dr Yadlapati reviews her address on peroral endoscopic myotomy (POEM) and the factors that must be balanced and taken into account when using POEM in the treatment of achalasia because, she insists, one size does not fit all.

Rena Yadlapati, MD, is director of the Center for Esophageal Diseases and associate professor of Clinical Medicine at the University of California San Diego. 

TRANSCRIPT:

Hi, I'm Dr. Rena Yadlapati, associate professor at UC San Diego, where I direct the Center for Esophageal Diseases. And in DDW, I got to give a talk that was titled POEM, Does One Size Fit All for achalasia? Now, I think that this was a rhetorical question that was asked of me because one size never fits all for achalasia, in my perspective. But the things that we talked about is when we decide that a patient is a candidate for POEM, there are many factors that we need to consider that inform the POEM technique.

So first of all, should this be an anterior or a posterior myotomy? Well, when POEM was first introduced, it was an anterior approach really in hopes of preserving those sling fibers and reducing post-POEM GERD. But now we're learning that the posterior approach can be very effective and maybe technically more feasible. And certainly if a patient has had a prior myotomy or is going to undergo a fundoplication, that'll determine whether you need to take an anterior or posterior approach.

How about full thickness versus a selective circular muscle thickness myotomy? Again, when POEM was first introduced, there was a lot of effort made to try a selective myotomy and preserve some tone, especially at the EGJ. But data from systematic review meta-analysis shows similar outcomes between both the full thickness and a selective circular myotomy, and the full thickness is shorter in procedure duration. So generally most are favoring a full thickness approach, but this can also be personalized.

Where we do see a lot of tailoring is the nanometric subtype of achalasia. So for instance, type 1 and type 2 achalasia, a short myotomy is favored. So about 3 to 4 centimeters on the esophageal side, 2 centimeters on the gastric side. And meta-analyses show that there are similar clinical outcomes between a short and a standard myotomy, but certainly the procedure length is less with a shorter myotomy, and there's less rates of erosive esophagitis and elevated acid exposure after the POEM doing a short myotomy approach. So again, a short myotomy is favored.

Now in type 3 achalasia, the myotomy is tailored to the spastic segment that is determined on the high resolution manometry. And this is really an effort to reduce the risk of a blown-out myotomy. If a myotomy that's too short is done and there's ongoing spasm or there's still ongoing tone at the EGJ, this could risk development of a diverticulum forming at the myotomy site, in which case sometimes the only treatment options that remain are perhaps an esophagectomy.

Now, in terms of post-POEM GERD, if you think your patient's going to be at risk of GERD following POEM, you might consider an antireflux intervention down the line, and this could include endoscopic fundoplication or other interventions. But we have learned at DDW this year that the rates of GERD are waning over time. And so it may be important to wait a few months after the POEM to really see if it's needed. Generally, about 50% of patients will still end up being on PPI therapy following their POEM.

And finally, we talked a lot about other types of motor disorders for which we want to be really careful about a POEM technique. So for instance, hypercontractile esophagus and distal esophageal spasm. Is LES preservation during the POEM okay? There might be risk of a blown-out myotomy formation if we preserve the LES, and so it's really unclear whether we should be cutting across the LES or not. And that's something that I think more research is going to be coming about in the near future. And finally, opioid-induced esophageal dismotility, the outcomes following POEM are poor, and so we really need to be very cautious and conservative for these cases and think about POEM very cautiously and expect that the rates of response might be lower. So it was really great talking about does one size fit all. I hope I've convinced you all that the answer is no. Thank you.