Vasculopathy in mitochondrial disorders

Objectives: Mitochondrial disorders (MIDs) are usually multisystem diseases and may manifest in addition to other systems also in the vasculature. Method: Literature review by using appropriate key words. Results: Vasculopathy in MIDs particularly manifests in arteries in form of a macroor microangiopathy. Direct evidence for microangiopathy in MIDs derives from the following findings: histologically confirmed generalised microangiopathy in MELAS patients; increased mtDNA mutation load in leptomeningeal and cortical vessels of MELAS patients; strongly SDH-reactive blood vessels on muscle biopsy in MELASand MERRF-patients; swollen endothelial cells in MERRF-patients. Findings indicating macroangiopathy include: dilation of the aorta in MID patients; aortic rupture in MELAS-patients; spontaneous cerebral artery dissection in MELAS-patients; transient occlusion of internal carotid artery in MID-patients; or high prevalence of premature atherosclerosis in MID-patients. Indirect evidence for vasculopathy in MIDs derives from findings like: stroke-like lesions, which also contain areas of cytotoxic edema; decreased cerebral perfusion on SPECT and perfusion-CT in MELAS-patients; migraine frequently associated with MID; CADASIL-patients, which develop features of MID and carry mtDNA mutations; impaired CO2 reactivity of intracerebral arteries in MID-patients; or reduced flow-mediated vasodilation due to altered NO-generation. Conclusion: Endothelial cells or smooth muscle cells of large or small arteries may be affected in MIDs. Arteriopathy in MIDs contributes significantly to the course and outcome in these patients and is often the cause of premature morbidity or mortality