Arteriovenous fistula

Arteriovenous fistula
Illustration of an arteriovenous fistula
Specialty	Cardiology

An arteriovenous fistula is an abnormal connection or passageway between an

Hereditary hemorrhagic telangiectasia is a condition where there is direct connection between arterioles and venules without intervening capillary beds, at the mucocutaneous region and internal bodily organs. Those who are affected by this conditions usually do not experience any symptoms. Difficulty in breathing is the most common symptom for those who experience symptoms.^[3]

Just like

• Congenital (developmental defect)[5]
• Rupture of arterial aneurysm into an adjacent vein^[5]
• Penetrating injuries^[5]
• Inflammatory necrosis of adjacent vessels^[5]
• Complication of catheter insertion rarely causes arteriovenous fistula. It is usually caused by brachial artery puncture because brachial artery is located between two brachial veins.^[6]

Surgically created Cimino fistula is used as a vascular access for hemodialysis. Blood must be aspirated from the body of the patient, and since arteries are not easy to reach compared to the veins, blood may be aspirated from veins. The problem is that the walls of the veins are thin compared to those of the arteries. The AV fistula is the solution for this problem because, after 4–6 weeks, the walls of the veins become thicker due to the high arterial pressure. Thus, this vein can now tolerate needles during hemodialysis sessions.

Mechanism

When an arteriovenous fistula is formed involving a major artery like the

An arteriovenous fistula can increase preload.^[8] AV shunts also decrease the afterload of the heart. This is because the blood bypasses the arterioles which results in a decrease in the total peripheral resistance (TPR). AV shunts increase both the rate and volume of blood returning to the heart.^{[citation needed]}

Diagnosis

The diagnosis of this condition can be done via ultrasound^{[citation needed]}

See also

References