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Coronary artery fistula — Clinical Guidelines

Overview

Coronary artery fistulas are abnormal connections between a coronary artery and a cardiac chamber or major vessel, often congenital but occasionally acquired. They can lead to hemodynamic disturbances and may require intervention if symptomatic or causing significant shunting 1 2 3.

Diagnosis

Clinical Presentation: Continuous murmurs, often heard at the left sternal border 1 2.

Imaging Techniques: Transesophageal echocardiography (TEE) offers precise visualization of fistula origin, course, and drainage site; transthoracic echocardiography (TTE) may show drainage flow but with less detail 5.

Radionuclide Imaging: Useful for detecting fistulas involving extracardiac structures, such as vertebral artery fistulas 6.

Management

Transcatheter Closure: Preferred minimally invasive approach using devices like Amplatzer Vascular Plug or coils 1 2 3 4.

- Device Selection: Choose a plug diameter twice the narrowest segment of the fistula 3. - Approach: Retrograde approach through an arteriovenous loop is feasible and avoids additional devices 2.

Occlusion Devices: Conventional metallic coils, floppy tips of coronary angioplasty guidewires, Amplatzer duct occluder, and Amplatzer septal occluder have been used 4.

Special Populations

Pediatrics: Transcatheter closure with Amplatzer Vascular Plug is feasible and effective in adolescents 2 3.

Comorbidities: No specific recommendations provided for elderly or comorbid conditions; individualized assessment is advised 4.

Key Recommendations

Consider Transcatheter Closure for Symptomatic or Hemodynamically Significant Coronary Fistulas (Evidence: Moderate 4)

Use Amplatzer Vascular Plug for Closure, Selecting Device Diameter Based on Fistula Narrowest Segment (Evidence: Weak 3)

Retrograde Approach Through Arteriovenous Loop May Be Preferred for Simplicity and Efficiency (Evidence: Expert opinion 2)

References

1 Agasthi P, Graziano JN. Challenging Case of Percutaneous Closure of Right Coronary Artery to Right Atrial Fistula. The Journal of invasive cardiology 2020. link 2 Kassaian SE, Alidoosti M, Sadeghian H, Dehkordi MR. Transcatheter closure of a coronary fistula with an Amplatzer vascular plug: should a retrograde approach be standard?. Texas Heart Institute journal 2008. link 3 Fischer G, Apostolopoulou SC, Rammos S, Kiaffas M, Kramer HH. Transcatheter closure of coronary arterial fistulas using the new Amplatzer vascular plug. Cardiology in the young 2007. link 4 Trehan V, Yusuf J, Mukhopadhyay S, Rangasetty UC, Mehta V, Gupta MD et al.. Transcatheter closure of coronary artery fistulas. Indian heart journal 2004. link 5 Yang Y, Bartel T, Caspari G, Eggebrecht H, Baumgart D, Erbel R. Echocardiographic detection of coronary artery fistula into the pulmonary artery. European journal of echocardiography : the journal of the Working Group on Echocardiography of the European Society of Cardiology 2001. link 6 Rockett JF, Moinuddin M, Robertson JT, Bernard SC. Vertebral artery fistula detected by radionuclide angiography: case report. Journal of nuclear medicine : official publication, Society of Nuclear Medicine 1976. link

Coronary artery fistula