Case report
Percutaneous closure of Waterston shunt in an adult after correction of congenital heart disease – a case report

Introduction

In patients with cyanotic congenital heart diseases and diminished pulmonary blood flow, palliative procedures are performed in order to increase pulmonary flow, and therefore to decrease tissue hypoxia due to direct or indirect connection of pulmonary arteries and systemic veins or systemic circulation. The Waterston shunt, first introduced in 1962, was the side-to-side anastomosis of the right pulmonary artery with the ascending aorta [1]. Because of the high complication rate and difficulties during shunt occlusion, this surgery has not been performed for many years. The most common complications of the Waterston shunt are stenosis and “bending” of the right pulmonary artery with unequal pulmonary flow, pulmonary hypertension or left ventricular failure due to long-lasting volume overload [2, 3]. Currently, increasingly often, the total correction of the defect is performed without prior palliative shunt.

Case report

A thirty-year-old man with congenital heart disease composed of double outlet right ventricle, subvalvular and valvular pulmonary stenosis and ventricular septal defect, after Waterston shunt in the 1st year of life and Blalock-Taussig shunt in the 5th year of life, after complete correction of the disease (VSD closure with a velour patch, enlargement of the pulmonary artery using a pericardial patch, closure of the aorto-pulmonary shunts), with severe pulmonary valve regurgitation and patent Waterston shunt was admitted to the ward due to another episode of decompensated heart failure which had occurred several times in the preceding half of the year.

Physical examination revealed resting dyspnoea, hepatomegaly, ascites and peripheral oedema. Chest X-ray showed a massively enlarged heart, dilated pulmonary arteries and their ramifications in the pulmonary hili and a reduction of the peripheral pulmonary arterial circulation. Laboratory examinations disclosed increased hepatic markers (GPT 102 U/l, GOT 68 U/l, -GTP 268 U/l) and NT-proBNP (3697 pg/ml). Echocardiographic examination showed significant pulmonary regurgitation with enlarged, hypo­kinetic right ventricle and dilated left ventricle (up to 6 cm in diastole) with global, severe hypokinesis (LVEF = 20%).

Cardiac magnetic resonance demonstrated the presence of left-to-right systolodiastolic flow of about 50 ml/heart cycle through the Waterston shunt (which comprised about 60% of the left ventricular output) with Qp : Qs = 3 : 1. The patient required administration of intravenous diuretics (furosemide, aldactone) and catecholamines (dobutamine, dopamine). Due to lack of clinical status improvement despite intensive pharmacological treatment it was decided to perform percutaneous closure of the Waterston shunt.

To close the shunt a 5 mm Amplatzer Septal Occluder was introduced through the 7 Fr delivery system via the femoral artery and was used to tightly seal the left-to-right shunt (fig. 1-3).

The patient’s clinical condition improved in the following days. Catecholamines were withdrawn and an oral diuretic was introduced. The patient was discharged from the hospital in a good condition. Examinations performed 2 months after the procedure showed impro­vement of the left ventricular ejection fraction (LVEF = 26%). Nevertheless, there was a persistent very low maximal oxygen uptake (max. V VO2 = 9.2 ml/m²/min). At this moment a decision regarding surgical correction of the pulmonary regurgitation has not been made.

Discussion

Waterston shunt is currently a historical method of treatment. The most frequently observed complication after this kind of procedure was pulmonary hypertension caused by increased pulmonary inflow. This was related to the fact that tailoring of the right shunt size was very difficult. Another problem consisted of asymmetric pulmonary inflow caused by bending and stenosis of the right pulmonary artery. A long-lasting left ventricular volume overload (as in congenital heart disease with coexisting shunt) caused left ventricular dilation and failure. Additional problems included difficulties in the surgical closure of the shunt [4].

In the presented case, complete correction of the congenital heart disease was performed in the 5th year of life. It consisted of VSD closure using a velour patch, pulmonary artery enlargement using a pericardial patch, closure of the Blalock-Taussig shunt and an attempt to close a Waterston shunt. Several years after the correction the shunt was still patent and led to a continuous left-to-right flow with a pulmonary-to-systemic ratio of 2 : 1, which caused a left ventricular volume overload. For that reason the patient was qualified for reoperation, which he refused.

In the course of several years, symptoms of severe biventricular failure developed. The patient was in a severe clinical condition and a surgical procedure could not be performed due to unacceptable risk. Heart transplantation was debated and subsequently renounced because of the high pulmonary pressure. The shunt was successfully closed percutaneously using the Amplatzer occluder. Reduction of left ventricular volume overload led to an immediate improvement of the patient’s clinical condition. It was possible to withdraw intravenous diuretics and catecholamines and to introduce oral diuretics, which permitted continuation of treatment at home. Control examinations performed after 2 months showed improvement of the left ventricular ejection fraction. Percutaneous closure of the patent Waterston shunt led to stabilization of the patient’s condition. Control examinations planned for the following months will demonstrate if there is a chance of continued improvement of the left ventricular function which could permit surgical treatment of the pulmonary regurgitation.

References

1. Waterston DJ. Treatment of Fallot’s tatralogy in children under one year of age. Rozhl Chir 1962; 41: 181.

2. Therrien J, Webb GD. Congenital heart disease in adults. In: Braunwald E, Zipes D, Libby P (eds.) Heart disease: a textbook of cardiovascular medicine. 6th ed., Philadelphia, WB Saunders Co. 2001; 1592-1621.

3. Hoffman P, Białkowski J, Demkow M, et al. Standardy Polskiego Towarzystwa Kardiologicznego – Wady wrodzone serca u dorosłych 2000. http://www.ptkardio.pl/files/file/2000_3.

4. Wojtalik M, Henschke J, Skalski JH. Zabiegi łagodzące. http://www. kardiochirurgiadziecieca.cm-uj.krakow.pl/r17.pdf.