Who should follow up on Median Arcuate Ligament Syndrome (MALS) patients?

Follow-Up for Median Arcuate Ligament Syndrome (MALS)

MALS patients should be followed by a multidisciplinary vascular team on a regular basis, with surveillance imaging at 1,6, and 12 months post-intervention, then annually thereafter. 1

Primary Follow-Up Responsibility

• A vascular team should manage all MALS patients, as recommended by the 2024 ESC Guidelines for peripheral arterial and aortic diseases 1
• The multidisciplinary approach should include vascular surgeons, interventional radiologists, and gastroenterologists to achieve optimal outcomes 1

Surveillance Imaging Schedule

Post-Revascularization Protocol:

• First surveillance imaging at 1 month post-intervention 1
• Repeat imaging at 6 months after the procedure 1
• Third surveillance at 12 months 1
• Annual imaging thereafter to monitor for recurrence 1

The Society for Vascular Surgery recommends duplex ultrasound (DUS) as the primary surveillance modality at these intervals 1. Computed tomography angiography (CTA) may be used as an alternative or complementary imaging technique 1.

Clinical Assessment Parameters

At each follow-up visit, assess:

• Clinical and functional status including symptom resolution or recurrence 1
• Hemodynamic status to evaluate adequacy of revascularization 1
• Limb symptoms (if applicable to broader mesenteric ischemia concerns) 1
• Medication adherence for antiplatelet or anticoagulation therapy 1
• Cardiovascular risk factors requiring ongoing management 1
• Weight changes and resolution of food aversion 1

Rationale for Intensive Surveillance

• Recurrent acute mesenteric ischemia after mesenteric revascularization accounts for 6-8% of late deaths, making surveillance critical 1
• Freedom from reintervention is only 64% at 6 months even with optimal multidisciplinary management 1
• Persistent celiac stenosis >30% may require additional intervention with stenting or surgical bypass 1

Special Monitoring Considerations

For patients with residual stenosis:

• More frequent imaging may be warranted if residual celiac artery stenosis exceeds 30% after surgical release 1
• Consider additional revascularization (endovascular stent or surgical bypass) if symptoms persist or recur 1

For patients with collateralization:

• Patients with mesenteric collateralization on angiography may be less likely to benefit from surgical release and require closer monitoring 1

Common Pitfalls to Avoid

• Do not rely solely on imaging findings—clinical symptom assessment must always accompany imaging surveillance 1
• Do not delay intervention for recurrent symptoms—symptomatic recurrence warrants prompt vascular team evaluation 1
• Do not use inconsistent imaging protocols between follow-up visits, as this makes comparison difficult and may miss subtle progression 1
• Do not assume symptom resolution is permanent—long-term data beyond 5 years are lacking, necessitating continued surveillance 2

Long-Term Outcomes Monitoring

• Complete symptom resolution occurs in approximately 75% of patients at 6 months when using a multidisciplinary approach 1
• Symptomatic relief is reported in 84.6% of patients after surgical MAL release 1
• Patients with vascular reconstruction in addition to decompression have 76% persistent symptom resolution compared to 53% with decompression alone 1