Medial Arcuate Ligament Syndrome, MALS, is a rare vascular compression disorder characterized by the external compression of the celiac artery and the celiac ganglion by the median arcuate ligament, a fibrous band of the diaphragm. This compression can lead to reduced blood flow as well as dysfunction of the nerves connecting to the abdominal organs, causing symptoms such as postprandial abdominal pain, weight loss, nausea, and sometimes an audible abdominal bruit. The downward movement of this ligament on expiration can worsen the compression.

In some cases, the median arcuate ligament is compressing the celiac ganglions without compressing the artery which sits just below the ganglions. This is called neurogenic Median Arcuate Ligament Syndrome, or nMALS. Because there is no imaging evidence of arterial compression, this diagnosis is not universally agreed upon by the vascular specialists. Experts in this fields do tend to appreciate the fact that inflammatory changes of the celiac ganglions due to repeated compression from the movement of the low lying diaphragm is enough to cuase the symptoms, and subsequent resolution of them upon successful surgical outcome. Because there’s no imaging to correlate with the symptoms, a strong clinical suspicion is supported with a celiac ganglion block.

While these are three most common presenting symptoms, patients present with many more symptoms related to MALS that has resolved with surgical correction. Our observations include:

Difficulty taking a deep breath
Exercise-induced shortness of breath
Tightness around the lower chest “bra-line squeezing sensation”
Increased heart rate on oral intake
Mid back pain
Pelvic pain
Bilateral flank pain
Postural orthostatic tachycardia syndrome

Diagnostic Work Up

CT | MR | Mesenteric Duplex | Angiogram

Angiogram: Inspiration