Successful Retrieval of a Migrated Shunt Catheter Causing Severe Pulmonary Insufficiency.

We report a case of a woman who presented with worsening shortness of breath due to a migrated ventriculoatrial shunt catheter into the pulmonary artery causing severe pulmonary insufficiency. She underwent surgical catheter removal. The majority of the catheter was easily retrieved; however, there were areas where the catheter was embedded into the myocardium, which would have posed a challenge with an endovascular approach.

INTRODUCTION

A ventriculoatrial (VA) shunt is an established treatment for hydrocephalus. The preferred distal site to shunt the cerebrospinal fluid is the peritoneal space with the ventriculoperitoneal (VP) shunt; however, previous intra-abdominal infection or scarring may necessitate alternative sites such as the atria of the heart or pleural space. Complications of the VA shunt include malfunction, infection, or thromboembolism; however, migration of catheter to the pulmonary artery is rarely reported.

CASE REPORT

A 50-year-old woman with an extensive medical history including spina bifida and hydrocephalus with placement of VA shunt and subsequent VP shunt due to VA shunt failure, both in her early 20s, presented with worsening shortness of breath for several years. An echocardiogram revealed normal left and right ventricular size, and systolic function however showed severe pulmonic valve insufficiency secondary to a migrated VA shunt catheter into the pulmonary artery [Figure 1a and b]. Color Doppler and continuous wave Doppler assessment was consistent with severe pulmonic insufficiency with large regurgitant jet size and broadwidth (vena contracta jet width to transpulmonary annulus ratio 64%) as well as a dense jet on continuous wave Doppler with greatly increased pulmonic systolic flow compared to systemic flow by pulsed wave Doppler [Figure 1c and d]. She underwent an exercise stress echocardiogram to assess her functional capacity but was only able to tolerate 3 min of exercise on a standard Bruce protocol, achieving 4.6 METS with a peak heart rate of 210 bpm (124% of the maximum predicted heart rate) limited by exertional dyspnea. The stress echocardiogram was nondiagnostic for the detection of ischemia due to submaximal workload achieved; however, no segmental wall motion abnormalities were seen. Pulmonary artery systolic pressure increased from 27 to 58 mmHg with exercise. She previously presented to the hospital with chest pain after outpatient pharmacologic stress myocardial perfusion imaging test that revealed moderate ischemia and scarring of the apical anterior and apical walls. She had coronary angiography, which did not reveal obstructive coronary artery disease but identified the migrated VA shunt catheter into the pulmonary artery [Figure 2a]. Computed tomography scan of the chest with contrast was performed to rule out pulmonary embolism and further evaluate the migrated shunt catheter, which was negative for pulmonary embolism, and the retained catheter was noted to be coiling in the main pulmonary artery [Figure 2b]. A multidisciplinary team discussion was held, and removal of this entrenched indwelling catheter through endovascular approach was considered to be too risky. She subsequently underwent open surgical intracardiac catheter removal and repair of the pulmonary artery with a bovine pericardial patch. The majority of the catheter was easily retrieved; however, there were areas that were embedded into the right ventricle myocardial wall as well as the superior vena cava [Figure 3]. The portion of the catheter adherent to the right ventricle wall was carefully excised; however, the adhesion to the superior vena cava was extensive and was therefore that portion was left in place. The pulmonic valve appeared to be well functioning, and it was deemed not necessary to proceed with pulmonic valve replacement. An echocardiogram obtained 2 months after the surgery showed improvement of pulmonic insufficiency, and the shunt catheter was no longer visualized. At 6-month follow-up, the patient reported significant improvement in her symptom.

Figure 1

Transthoracic echocardiography: (a) Parasternal long view showing the ventriculoatrial shunt catheter in the right ventricle (arrow), (b) parasternal right ventricle outflow view showing the ventriculoatrial shunt catheter in the right ventricle outflow (arrow), (c) parasternal short view showing severe pulmonic insufficiency with wide vena contract and large regurgitant jet size that occupies more than 50% of the right ventricle outflow tract, (d) continuous wave Doppler recording through the pulmonic valve on parasternal short view showing dense continuous wave signal and increased systolic flow velocity

Figure 2

(a) Cardiac catheterization film showing a migrated ventriculoatrial shunt catheter that made a loop into the pulmonary artery with the tip of the catheter in the right ventricle, (b) computed tomography scan showing a migrated ventriculoatrial shunt catheter into the pulmonary artery

Figure 3

Operative pictures showing the looped shunt catheter (a) that was partially embedded into the right ventricular wall and the superior vena cava with thrombus and fibrin sheath on the catheter (b-c). Excised shunt catheter showing the adhered tissues (d)

DISCUSSION

This report represents a rare case of migration of a VA shunt catheter across the pulmonic valve resulting in symptomatic severe pulmonic insufficiency. VA shunt was the mainstay of therapy for hydrocephalus until about 40 years ago after which it was largely replaced by VP shunt for superior safety.[1] Although it is extremely rare, numerous case reports have been published for VA and VP shunt migration into the heart.[23] The proposed mechanism of catheter migration is that the subcutaneous catheter guide perforates the internal or external jugular vein during the shunt procedure, and negative pressure in the vein draws the catheter into the heart despite no evidence of subcutaneous hematoma or sign of vessel injury during the original shunt procedure.[45] The VA shunt catheter is positioned in the atrium during the initial procedure; however, the negative pressure can theoretically draw the catheter more-and-more downstream into the heart. The treatment approach as well as the role of the cardiologist, the interventional radiologist, or the cardiac surgeon remains uncertain. A percutaneous approach has been proposed to be safe by Fewel and Garton; however, Morell et al. emphasized that if the interval since the insertion is long, potential adhesion of the shunt catheter to intracardiac structures can be problematic for percutaneous removal.[67] In the present case, we discussed various treatment options involving the interventional cardiologist, interventional radiologist, and the cardiac surgeon and collectively decided that it would be safest to remove the catheter with an open surgical approach given the concern for adhesion to the pulmonic valve, pulmonary artery, or other intracardiac structures. During the surgery, the shunt catheter was, in fact, adhered to the right ventricle as well as the superior vena cava and open-heart approach was indeed the safer option. The VA shunt catheter was successfully retrieved without compromising the pulmonic valve or other intracardiac apparatus. The catheter adherence to the intracardiac structure illustrated the potential challenge if an endovascular approach was chosen.

The migration of a VA shunt catheter is rare; however, it can cause symptomatic severe pulmonic insufficiency. The potential adherence of the catheter to the intracardiac apparatus poses a challenge on the optimal treatment option.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.