The spectrum of COL4A1-related disorders is well described, and includes: small-vessel brain disease of varying severity, eye defects (retinal arterial tortuosity, Axenfeld–Rieger anomaly, cataract) and some systemic findings (kidney involvement, muscle cramps, cerebral aneurysms, Raynaud phenomenon, cardiac arrhythmia, and hemolytic anemia) [17,18]. This evidence concerns the gene COL4A1 and cardiac arrhythmia.