What constitutes scopic surveillance for a patient with a history of achalasia and previous Peroral Endoscopic Myotomy (POEM) surgery?

Endoscopic Surveillance After POEM for Achalasia

All patients with achalasia who have undergone POEM should receive long-term endoscopic surveillance to monitor for disease progression, asymptomatic GERD complications, and esophageal cancer risk. 1

Core Components of Post-POEM Surveillance

Initial Post-Procedure Assessment (6-12 months)

• Upper endoscopy to evaluate for erosive esophagitis, Barrett's esophagus, strictures, and structural abnormalities 1
• 24-hour pH monitoring to objectively document pathologic acid exposure, as 25% of patients with esophagitis remain asymptomatic 1
• High-resolution manometry (HRM) to assess lower esophageal sphincter function and treatment efficacy 2
• Timed barium esophagram to evaluate esophageal clearance and structural changes 1

Rationale for Comprehensive Surveillance

The need for ongoing monitoring is driven by multiple high-risk factors:

• High GERD burden: 41-65% of post-POEM patients develop esophagitis, with 41-56% showing abnormal acid exposure on pH monitoring 1
• Asymptomatic disease: Up to 25% of patients with erosive esophagitis have no reflux symptoms, making symptom-based monitoring inadequate 1
• Progressive esophagitis: 31% of patients with initially normal endoscopy develop esophagitis at subsequent surveillance (mean 29 months), including new Barrett's esophagus in some cases 1
• Elevated cancer risk: Patients with achalasia have a 5-fold increased risk of esophageal cancer (HR 4.6,95% CI 2.3-9.2) compared to the general population 1

Long-Term Surveillance Strategy

Endoscopic surveillance should be performed at regular intervals, though specific timing remains an area of ongoing investigation 1. The most practical approach includes:

• Alternating modalities: Some expert centers alternate between esophagram and endoscopy to monitor structural changes, esophageal clearance, and mucosal abnormalities 1
• FLIP integration: Functional luminal impedance planimetry (FLIP) can be incorporated during endoscopy to assess esophagogastric junction opening 1
• Objective reflux assessment: Follow-up pH monitoring should be strongly considered even in asymptomatic patients, as symptoms alone are insufficient to detect pathologic acid exposure 1

Evaluation for Treatment Failure

Approximately 10-15% of patients experience persistent or recurrent symptoms after POEM 1. When symptoms recur, comprehensive re-evaluation must include:

• Repeat esophagogastroduodenoscopy to assess for structural complications 1
• High-resolution manometry to evaluate LES function 1
• Timed barium esophagram to assess esophageal emptying and identify anatomic issues 1

Critical Pitfalls to Avoid

• Relying on symptoms alone: One-quarter of patients with esophagitis are asymptomatic, making objective testing essential 1
• Discontinuing surveillance prematurely: Achalasia is a chronic progressive condition requiring lifelong monitoring 1
• Ignoring reflux in asymptomatic patients: Erosive esophagitis can progress silently to Barrett's esophagus without intervention 1
• Failing to distinguish reflux types: Post-POEM chest pain may represent pathologic acid reflux, nonreflux esophageal acidification from food stasis, or visceral hypersensitivity—objective testing is required for differentiation 1

Management Based on Surveillance Findings

• If erosive esophagitis is detected: Optimize PPI therapy and consider lifelong acid suppression given the high rate of abnormal acid exposure post-POEM 1
• If Barrett's esophagus develops: Follow established Barrett's surveillance protocols given the already elevated baseline cancer risk 1
• If treatment failure is confirmed: Consider repeat POEM, which may be superior to pneumatic dilation for failed initial myotomy 1

The goal of implementing this surveillance strategy is to tailor interventions that may delay or prevent progression to end-stage achalasia while identifying and managing GERD complications before they become symptomatic or lead to malignancy 1.