What are the other Names for this Condition? (Also known as/Synonyms)

• Acquired Coronary Artery Fistula
• CAF (Coronary Artery Fistula)
• Congenital Coronary Artery Fistula

What is Coronary Artery Fistula? (Definition/Background Information)

• Coronary Artery Fistula (CAF) is a heart condition characterized by an abnormal connection between a coronary artery (the blood vessel that carries oxygen-rich blood to the heart) and another blood vessel or the heart chamber
• Coronary Artery Fistulas are classified into several types based on the blood vessel of origin, segment of origin, site and mode of termination, fistula morphology and numbers, fistula size (based on angiographic studies), and physiological abnormalities
• Coronary Artery Fistula is a rare condition and most of the affected individuals may have other heart defects as well. CAF is often congenital in nature and children may be born with this condition (in over 90% of the cases)
• In case of Coronary Artery Fistula manifesting at birth, it usually occurs when one of the coronary arteries does not develop properly during gestation. However, some individuals may also develop this condition after birth, termed Acquired CAF. It is reported that much less than 10% of the cases are acquired
• The condition can result in chest pain, heart murmur, and fatigue. In some individuals, severe complications such as rupture of the fistula, cardiac arrhythmias, or even heart failure may develop from Coronary Artery Fistula
• Coronary Artery Fistula is usually treated through a corrective surgery to restore proper blood flow to the heart. With early diagnosis and prompt treatment, the prognosis of Coronary Artery Fistula is typically good; a majority of the affected individuals recover well and have a normal life-span

Who gets Coronary Artery Fistula? (Age and Sex Distribution)

• Coronary Artery Fistula is a rare condition that comprises less than 0.5% of all congenital cardiac anomalies
• Both males and females are equally affected by this heart condition
• It may be seen in individuals of any age, but it is most commonly diagnosed in early childhood when an irregular heartbeat is detected
• Coronary Artery Fistula is prevalent among all racial and ethnic groups

What are the Risk Factors for Coronary Artery Fistula? (Predisposing Factors)

Some known risk factors for Coronary Artery Fistula include:

• Heart surgeries that include any of the following:
  • Coronary artery bypass grafting (CABG)
  • Coronary stenting
  • Endomyocardial or transbronchial biopsy
  • Epicardial procedures
  • Pacemaker implantation
  • Radiofrequency ablation
  • Valve surgeries
• Any infection that may weaken the heart such as infective endocarditis
• Vasculitis of the coronary arteries, wherein inflammation of the coronary arteries is noted
• Injury to the heart, typically a penetrating chest trauma

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Coronary Artery Fistula? (Etiology)

Coronary Artery Fistula may be caused by certain biological factors during gestation or after birth.

• Congenital Coronary Artery Fistula: It occurs from factors before birth, such as due to an incorrect formation of the coronary artery during gestation
• Acquired Coronary Artery Fistula from factors that may include:
  • An infection weakening the wall of the coronary artery and the heart 
  • Certain heart surgeries
  • A penetrating injury to the chest from an accident or a trauma
  • Coronary vasculitis

What are the Signs and Symptoms of Coronary Artery Fistula?

The signs and symptoms depend on the classification type of Coronary Artery Fistula and may include:

• Heart murmur
• Chest pain that may be chronic
• Shortness of breath
• Slow physical growth and development during childhood
• Fast or irregular heartbeat
• Fatigue
• Fainting, in some cases
• Signs and symptoms of any existing comorbidity may be noted

In a majority of cases, small and asymptomatic fistulas grow to become large and symptomatic conditions.

How is Coronary Artery Fistula Diagnosed?

A diagnosis of Coronary Artery Fistula is made on the basis of information gathered from the following tests and exams:

• Complete physical evaluation and a comprehensive analysis of medical history
• Assessment of the presenting signs and symptoms
• Imaging tests that may include X-rays, coronary angiography, cardiac catheterization, echocardiogram, MRI and/or CT scans
• Treadmill testing and cardiopulmonary exercise testing (CPET)
• Differential diagnosis to rule out other conditions that may present similar signs and symptoms

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Coronary Artery Fistula?

The following complications of Coronary Artery Fistula may be observed in some individuals:

• Opening (rupture) of the fistula
• Poor oxygen supply to the heart
• Atrial fibrillation; a severe heart rhythm disorder
• Abnormal heart rhythm (arrhythmia)
• Heart attack
• Heart failure
• Complications that arise from surgical procedures to treat Coronary Artery Fistula

How is Coronary Artery Fistula Treated?

Coronary Artery Fistula may be treated as follows:

• The healthcare provider may determine the course of treatment for small and asymptomatic fistulas
• Surgical intervention is generally necessary for larger fistulas. It is the primary method of treatment, to close the abnormal connection of the blood vessels
• A coil or an occlusion device may be inserted into the heart with a catheter (a long thin tube) to close the abnormal connection
• Undertaking adequate treatment of any underlying condition or comorbidties

In some rare cases, the abnormal connection may close on its own and may not require any treatment.

How can Coronary Artery Fistula be Prevented?

At the present time, no methods or guidelines are available for the prevention of Coronary Artery Fistula, particularly if it is congenital in nature.

• However, seeking early medical treatment following the onset of symptoms may help prevent its progression into a severe disease
• Undertaking early treatment of any heart condition, such as an infection or trauma to the heart/chest, may help minimize one’s risk for Acquired CAF

What is the Prognosis of Coronary Artery Fistula? (Outcomes/Resolutions)

• The prognosis of Coronary Artery Fistula is typically good with treatment; most of the affected individuals generally do well after surgery. However, the prognosis can be unpredictable and vary from one individual to another
• A majority of individuals with Coronary Artery Fistula are known to have normal life-spans following appropriate treatment. However, a small percentage of the affected individuals may require multiple surgeries to correct the condition

Additions and Relevant Useful Information for Coronary Artery Fistula:

The following DoveMed website links are useful resources for additional information:

https://www.dovemed.com/common-procedures/procedures-surgical/coronary-artery-bypass-graft-cabg/

https://www.dovemed.com/common-procedures/procedures-surgical/pacemaker-implantation/