Management of Coronary Pulmonary Fistula
Large coronary pulmonary fistulas should be closed via either a transcatheter or surgical approach regardless of symptomatology, while small to moderate fistulas should be closed only when symptomatic or causing complications. 1
Definition and Prevalence
Coronary artery-pulmonary fistulas (CAVFs) are abnormal direct connections between coronary arteries and the pulmonary vasculature, bypassing the normal capillary network. They represent:
- 0.1-0.2% of all catheterized patients 1
- Second most common coronary artery congenital abnormality after anomalous origin of coronary arteries 1
- Can arise from either or both coronary arteries, typically draining into the pulmonary trunk or branches 1, 2
Risk Assessment and Clinical Presentation
Clinical Manifestations
- Many small fistulas are asymptomatic and detected incidentally 1, 2
- Symptomatic patients may present with:
Complications
- Myocardial ischemia and infarction 1
- Endocarditis 4
- Rupture of the fistula 1
- Arrhythmias 1
- Ventricular dysfunction 1
- Pulmonary hypertension (in large shunts)
Diagnostic Approach
If a continuous murmur is present, its origin should be defined using one or more of the following:
- Echocardiography (transthoracic with bubble study)
- MRI
- CT angiography
- Cardiac catheterization 1
Cardiac catheterization with coronary angiography remains the gold standard for definitive diagnosis and anatomical delineation of the fistula course and drainage site 1, 3.
Management Algorithm
1. For Large CAVFs:
- Intervention indicated regardless of symptoms 1
- Transcatheter or surgical closure should be performed after delineation of the fistula course 1
2. For Small to Moderate CAVFs:
A. With any of these conditions:
- Documented myocardial ischemia
- Arrhythmias
- Unexplained ventricular dysfunction
- Chamber enlargement
- Endarteritis
- Intervention indicated: Transcatheter or surgical closure 1
B. Without symptoms:
- Clinical follow-up with echocardiography every 3-5 years to monitor for:
- Development of symptoms
- Arrhythmias
- Progression of size
- Chamber enlargement 1
3. For Clinically Insignificant CAVFs:
- Intervention not indicated (normal-sized cardiac chambers, asymptomatic) 1
Treatment Options
1. Transcatheter Closure
- First-line approach for suitable anatomy 2
- Should be performed only in centers with expertise 1
- Devices used include coils, vascular plugs, and occluder devices 2
- Success rates are good with acceptable procedure-related morbidity 5
2. Surgical Closure
- Indicated when:
- Transcatheter approach is not feasible
- Complex anatomy
- Very large fistulas
- Concomitant cardiac surgery required
- Should be performed by surgeons with training and expertise in congenital heart disease 1
- Techniques include direct epicardial or endocardial ligation 5
Post-Intervention Follow-up
- Clinical evaluation with imaging (echocardiography) to assess:
- Resolution of symptoms
- Ventricular function
- Residual shunting
- Long-term follow-up to monitor for potential recanalization or development of coronary artery stenosis 2
Special Considerations
- In heart transplant recipients, fistulas may be observed if asymptomatic with normal cardiac dimensions and hemodynamics 6
- Patients with concomitant coronary artery disease may require additional interventions 4
- Small fistulas may close spontaneously over time 2
Pitfalls and Caveats
- Incomplete closure can lead to residual shunting
- Risk of device embolization during transcatheter procedures
- Potential for thrombus formation in venous channels
- Inadvertent occlusion of nearby non-fistulous branches must be avoided 1
- Myocardial infarction can occur as a complication of closure 2
By following this structured approach to management, clinicians can optimize outcomes for patients with coronary pulmonary fistulas while minimizing risks of complications.