Title:
Percutaneous device closure of hemodynamically significant coronary fistula following endomyocardial biopsy in a pediatric heart transplant patient
Introduction:
Coronary artery fistula (CAF) is a rare but well-documented complication of right ventricular endomyocardial biopsy (RVEMB), particularly in the adult population. Typically these fistulae never reach clinical or hemodynamic significance, and can be managed conservatively without intervention. We report a case of a significant CAF requiring device closure in the cardiac catheterization laboratory with subsequent improvement of clinical symptoms and diastolic function.
Clinical Case:
A 22 year old patient presented to the cardiac catheterization laboratory for surveillance RVEMB after undergoing orthotopic heart transplant as an infant secondary to failed stage I palliation for hypoplastic left heart syndrome. She had been diagnosed with a small CAF from the left anterior descending coronary artery (LAD) to the right ventricle three years prior, which had been followed conservatively; however, at the time of presentation, she reported a six-month history of new-onset exercise intolerance and substernal chest pain with exercise. Echocardiogram demonstrated the persistent CAF with left coronary artery and biventricular dilation. Angiography demonstrated diffuse dilation of the left main coronary artery and LAD, along with enlargement of the CAF. Despite the absence of a detectable left to right shunt by oximetry data, she had significant elevation of the left ventricular end diastolic pressure to 17 mmHg. Newly developed elevated filling pressures, symptoms concerning for myocardial perfusion abnormality with exercise, and ventricular dilation on echocardiogram led to the decision to close the CAF percutaneously. The CAF was cannulated retrograde from the femoral artery, and an arteriovenous wire loop was made by advancing a wire through the fistula into the right ventricle and pulmonary artery followed by snaring and externalization of the wire through the femoral vein sheath. A 4 French Glide catheter was advanced prograde over the wire into the distal CAF. A 6 mm Amplatzer Vascular Plug 4 device (Abbott, Chicago, Illinois) was delivered through the Glide catheter. Angiography following device deployment demonstrated no significant residual shunt through the fistula and no obstruction to the normal coronary flow. Dual antiplatelet therapy was initiated for coronary prophylaxis. She subsequently had resolution of symptoms, and repeat catheterization one year later demonstrated normalization of left ventricular end diastolic pressure to 10 mmHg with no residual shunt through the device. Additionally, follow up echocardiograms demonstrated normalization of ventricular size.
Discussion:
CAF following RVEMB has been well described in the literature. While there are no current major guidelines, management is typically conservative as these fistulae will often either close spontaneously or fail to reach hemodynamic significance. In extreme cases, the fistulae can become hemodynamically significant or even cause myocardial ischemia as was felt to be occurring in our patient. This case highlights the importance of following these patients closely with diligent investigation of new symptoms, and demonstrates that percutaneous closure of hemodynamically significant CAF remains a reasonable treatment option in these rarely encountered circumstances, leading to resolution of cardiac dysfunction and symptoms.