While ALGS is often categorized as a "liver disease," the cardiovascular system is involved in over 90% of cases. Peripheral Pulmonic Stenosis (PPS) is the most frequent finding, but more complex defects like Tetralogy of Fallot can also occur.

In 2026, there is an increased focus on neurovascular screening. Because the Notch signaling pathway is essential for blood vessel development, ALGS patients are at a higher risk for intracranial aneurysms and Moyamoya syndrome. Standard protocols now recommend that adolescent patients undergo at least one baseline MRA (Magnetic Resonance Angiogram) to check for "silent" vascular issues in the brain, as these can lead to strokes if left unmanaged.