ABSTRACT
Introduction Systemic arterio-venous fistulas are a group of vascular anomalies characterized by abnormal communications between systemic arteries and veins without normal capillary development. This situation results in shunting of blood from the high pressure arterial to the low pressure venous system. This abnormal circuit steals blood from the normal capillary bed and can result in tissue ischemia. Increased flow in the afferent artery and efferent vein causes dilatation, thickening, and tortuosity of the vessels. Depending on the shunt volume, it may cause right ventricular volume overload and decrease of the peripheral vascular resistance, leading to increased stroke volume and cardiac output. Such hemodynamics can lead to heart failure.
