Arteriovenous fistula

There are abnormal channels between arteries and veins, called arteriovenous fistulas. The normal blood flow of arteries into the accompanying veins can cause local vascular lesions of the fistula and hemodynamic changes in the local, peripheral circulation, and systemic system of the fistula. Can be congenital or acquired due to trauma. Arteriovenous fistula allows some arterial blood to flow directly into the vein without flowing through the capillaries of the tissue that should be perfused. This part of the blood does not undergo material exchange in the tissue and becomes an ineffective circulation. This can cause tissue ischemic necrosis; total peripheral resistance is reduced, blood pressure is reduced, and Cardiac compensation increases, returning blood volume exceeds heart load and heart failure. Arteriovenous fistula patients have peripheral varicose veins, slightly higher local skin temperature, hyperpigmentation, and ulceration; vascular murmurs or tremors may be present at the fistula. In the later stage, there is enlarged heart and heart failure.