Esophageal Motility: Spasm and Hypercontractile

0:00Welcome to Board Pearls. This is episode three of four of the Esophageal Motility chapter, in the Esophageal Disorders module. The last two episodes lived on one number, the integrated relaxation pressure, the IRP, because it answers the only question that reorganizes the entire differential: is the sphincter the problem, or not. Once achalasia is off the table, that question doesn't stop working, it just points the other way, into the body of the esophagus. A normal IRP means the sphincter is fine, so the problem is in the body, and the body can only fail in one of two ways, contracting too much or too little. This episode is the too-much side: distal esophageal spasm and the hypercontractile esophagus.

0:42Distal esophageal spasm and hypercontractile esophagus get taught together for a reason worth internalizing: they present identically, dysphagia and non-cardiac chest pain in someone whose heart is already cleared, and they share a normal IRP, which is the single fact that keeps them out of type three achalasia. So the moment you see a spastic-looking distal body, your first move isn't to name it, it's to look up at the IRP, because that number decides whether you're looking at a treatable body disorder or an unrelaxing sphincter wearing the same costume.

1:13Take spasm first. It's a normal IRP with a short distal latency on at least a fifth of swallows in a symptomatic patient, and the piece that actually teaches you something is what distal latency represents. It's the time from the sphincter opening to the contraction decelerating near the bottom of the esophagus, and when it runs under four and a half seconds, the contraction has arrived too early, squeezing a bolus with a wave that never properly propagated. That's the whole disease in one image, a premature squeeze. And the reason latency is the number you care about is that it tracks the symptom, it picks out the patients who actually have dysphagia, which is the only thing that earns a manometric number its place.

1:52Jackhammer, the hypercontractile pattern, is the mirror complaint, not too early but too hard, a normal IRP with a distal contractile integral, the DCI, over eight thousand on a fifth of swallows. The thing to understand rather than memorize is why the bar sits so high: eight thousand is deliberately well past anything a healthy esophagus ever generates, so it catches genuine abnormal vigor and leaves the upper tail of normal alone. That's the point of the number, you're not flagging a strong swallow, you're flagging a pathologically strong one, which is why the pattern only counts when the patient also has the symptoms to match.

2:31And here's the discipline that ties both together. The criteria require symptoms for either diagnosis, and that requirement is doing real work, not box-checking. Short-latency swallows and high-DCI swallows show up in healthy people, so on their own they aren't disease, and the classification explicitly calls them inconclusive without symptoms. Which means the vignette where a quarter of the swallows are premature but the patient has no dysphagia and no chest pain is a trap: the manometric pattern is necessary but never sufficient, and the answer is that this person doesn't have spasm.

3:07The sharper trap, though, is type three achalasia, and it's worth walking slowly because it's exactly where careful reading leads you wrong. Type three also fires premature contractions in the distal body, so the body tracing can look identical to spasm. The only thing separating them is the number you were told to check first, the IRP, which is elevated in type three because the sphincter isn't letting go. Read the body and forget the sphincter, and you'll call spasm when the truth is achalasia, and the two answers could not be further apart: premature contraction with an elevated IRP is type three achalasia and gets a tailored myotomy, usually POEM extended proximally, while premature contraction with a normal IRP is spasm and gets the medications instead. Same body, opposite management, and the IRP is the one thing that separates them. This is the recurring lesson of the chapter in miniature, the body pattern is never the answer by itself.

4:02Before you treat spasm or jackhammer as a primary disease, there's one more step: prove it isn't secondary, because several common things reproduce these exact patterns. Opioids lead the list, and understanding why matters, they act on enteric inhibitory neurons, raising the DCI and shortening the latency, so chronic oxycodone can manufacture spasm, jackhammer, or type three achalasia depending on which parameter dominates. That's why an opioid history flips your first therapeutic move from a procedure to simply stopping the drug and restudying. Reflux can drive the same hyperexcitable body, so reflux symptoms earn a PPI trial before you commit. Eosinophilic esophagitis can masquerade as a spastic tracing, so biopsies belong in the first endoscopy, not the third visit. And a mechanical narrowing below the sensor can force a compensatory high-DCI pattern, which is one more reason endoscopy comes before you ever call the motility primary. The point is that a manometric pattern is only a starting hypothesis, and clearing these mimics is how it earns the word diagnosis.

5:09Only once you've cleared them does treatment make sense, and the sequence follows a logic worth hearing rather than a list to recite. You're going after two things, relaxing the smooth muscle and calming the nerve hypersensitivity, and since the evidence is thin at every step, you start with the cheapest, safest option and move up only if it fails. Calcium channel blockers relax the muscle directly, diltiazem sixty to ninety milligrams four times daily or a sustained-release form, with short-acting nifedipine avoided for cardiovascular reasons. Nitrates before meals and sildenafil at fifty milligrams both work through the nitric-oxide pathway to the same end, and peppermint oil earns its odd place on the list precisely because menthol is itself a calcium channel blocker on smooth muscle. When relaxing the muscle fails, you switch targets rather than push harder, moving to a neuromodulator, a low-dose tricyclic like imipramine or amitriptyline at twenty-five to fifty milligrams at bedtime, or trazodone, or an SSRI, which quiets the afferent signal centrally instead of changing the contraction at all. Botulinum toxin and a long POEM myotomy come last, for refractory, disabling, well-documented disease, and the reason outcomes here are less predictable than in achalasia is that the manometry and the symptoms so often disagree.

6:31So the short version of the too-much body is this. A normal IRP keeps you out of achalasia, and then the body names itself by how it overdoes it: too early is spasm, on a short distal latency, and too hard is jackhammer, on a DCI over eight thousand. Both require symptoms to count, because the tracing alone shows up in healthy people, and both demand you clear the secondary causes first, opioids above all, then reflux, eosinophilic esophagitis, and mechanical obstruction. And the sharpest trap is that the very same premature-contraction body is type three achalasia the moment the IRP is high, which is why you always read the sphincter before you name the body.

7:11The next episode takes the other way a body fails on a normal IRP, doing too little: ineffective motility and the fundoplication question it decides, absent contractility, and scleroderma, where a failed pump meets an open sphincter. And it closes on the one finding you're required to distrust, outflow obstruction with an elevated IRP but peristalsis still firing.

7:33For the full chapter, the practice vignettes, and the topic-tagged question bank, head to board pearls dot com. You'll find the rest of the series on Apple Podcasts, Spotify, or wherever you listen to podcasts. That brings us to the end of episode three of four of chapter two, and I'll see you in the next one.