Inclusion Criteria:  Written informed consent Age: 18+ Sex: male/female Patients with the m.3243A>G mutation  Exclusion Criteria:  Use of anti-coagulants, anti-thrombotics and other medication influencing coagulation Have a weekly alcohol intake of ≥ 35 units (men) or ≥ 24 units (women) Current history of drug abuse Deficient immune system or autoimmune disease Significant concurrent illness Ongoing participation in other clinical trials Major surgery within 4 weeks of the visit Vaccination within 4 weeks of the visit Pregnant or lactating women Psychiatric or other disorders likely to impact on informed consent Patients unable and/or unwilling to comply with treatment and study instructions Any other factor that in the opinion of the investigator excludes the patient from the study A history of strokes Allergy for contrast fluid Peripheral signs of ischemia or vasculopathy