Endovascular repositioning and resizing of the distal catheter of a ventriculoatrial shunt

Abstract

Ventriculoatrial (VA) shunts are an effective alternative to ventriculoperitoneal shunts for diversion of cerebrospinal fluid in patients with hydrocephalus. Accurate placement of the distal end of a VA shunt in the right atrium is imperative for appropriate drainage and can be technically challenging. Misplaced or dislodged shunt catheter needs urgent repositioning, which can be performed by endovascular techniques. We present a case of VA shunt placement related complication, in which the dislodged distal fragment was retrieved by endovascular techniques. The remaining distal catheter, found to be in the internal jugular vein, was not only repositioned, but also resized for accurate placement in the right atrium.

Background

Ventriculoatrial (VA) shunts are an effective alternative to ventriculoperitoneal (VP) shunts for diversion of cerebrospinal fluid (CSF) in patients with hydrocephalus. Accurate placement of VA shunts in the right atrium (RA) is imperative for appropriate drainage and prevention of complications. We present a case of malpositioned distal end of a VA shunt with dislodged catheter, which was successfully retrieved and repositioned by endovascular approach.

Case presentation

An 8-year-old boy, with history of bilateral VP shunt placement done for congenital aqueductal stenosis at 1 and 7 years of age, presented with signs of raised intracranial pressure and shunt block. He had two episodes of generalised tonic clonic convulsions. On examination, the child was drowsy, with hypertonia of all four limbs, and a Glasgow Coma Scale of 7/15. A VA shunt placement was planned. During the procedure, the distal catheter of the shunt, which was to be placed in the RA, was dislodged and floating in the RA and inferior vena cava (IVC). The tip of the remaining distal catheter was coiled in the internal jugular vein (IJV) (figure 1).

Figure 1.

Fluoroscopic images of the neck showing coiled proximal end of the ventriculoatrial (VA) shunt in the neck, in the internal jugular vein (black arrow). The fragmented distal end of the VA shunt is seen dislodged in the right atrium-inferior vena cava junction (white arrow).

Hence, an endovascular approach was planned to retrieve the dislodged catheter, and reposition the distal tip of the catheter in the RA. Using a 7F right transfemoral venous access, and a 10 mm endovascular goose neck snare, the distal end of the dislodged catheter was retrieved across the femoral vein (figure 2). The coiled distal end of the intact shunt catheter in the right IJV was snared and pulled back into the RA (figure 3).

Figure 3.

(A–D) Coiled portion of the ventriculoatrial shunt was snared and pulled into the right atrium (RA). Note, in figure D, the tip of the catheter was across the RA into the inferior vena cava.

Figure 2Fluoroscopic images of the abdomen show the dislodged catheter being held using a snare (A) and pulled outside from the right femoral venous access (B). (C) The broken fragment of the ventriculoatrial shunt with a snare.

However, it was observed that the distal end of the straightened catheter was reaching across the RA into the IVC. For improved long-term patency, the distal catheter tip needs to be placed in the RA. In order to resize the catheter to reach up to the RA without surgical exploration, the left IJV was accessed using a 6F sheath. The tip of the catheter was snared across the left IJV using the endovascular snare. The vascular sheath was withdrawn, while the snare tightly gripped the catheter, pulling the catheter outside the skin. It was held tightly with the help of a pair of mosquito forceps and cut to appropriate size (figure 4A–D). The catheter was then pulled back into the RA using a pigtail catheter from the right femoral access (figure 4E, F). Hence, the dislodged catheter was retrieved, the distal catheter was repositioned and also resized (video 1). Check radiograph showed appropriately sized VA shunt with the tip in the RA (figure 5).

Figure 4.

Fluoroscopic images of the neck. The tip of the catheter was snared (A), pulled across the left internal jugular vein (B), caught using a pair of mosquito forceps (C) and cut to resize (D). The catheter was then pulled back into the right atrium using a pigtail catheter from the femoral route.

Video 1.

bcr-2021-248452supp001.mp4 ^{(668.9KB, mp4)}

DOI: 10.1136/bcr-2021-248452.video01

Figure 5.

Fluoroscopic image of the neck shows accurately placed distal end of a ventriculoatrial shunt catheter.

Outcome and follow-up

Postprocedure, the patient improved clinically with optimal shunt function. He was kept in the Intensive Care Unit and discharged 10 days postprocedure.

Discussion

Ventricular shunt placement is one of the most common neurosurgical procedures performed and is one of the most important procedures for management of hydrocephalus. Although VP shunt is the preferred procedure for CSF diversion, complications such as shunt obstruction, infection, peritoneal adhesions, make VA shunt a useful alternative in certain cases, with comparable long-term results.¹ Accurate placement of the distal end of a VA shunt may pose a technical challenge. Various techniques have been used for placement of the distal end, including fluoroscopy, ultrasound and transoesophageal echocardiography.² Low placement or antegrade migration of the catheter placement can lead to right atrial, ventricular thrombus formation, and even tricuspid regurgitation.³

In our case, due to technical complications, the distal catheter was dislodged in the RA. Endovascular retrieval of intravascular foreign bodies is a safe, minimally invasive and quick method, classically performed with the help of a goose neck/loop snare.⁴ Percutaneous retrieval of dislodged VA shunts has been described previously in literature with catheter migrations in the RA and even in the pulmonary artery.^{5 6} Also, repositioning of the distal catheter by endovascular approach has been described.⁷ In our case however, the distal end was not only dislodged, but also looped in the right IJV. After retrieval and repositioning, the tip of the catheter was across the diaphragm, in the IVC. Catheter tip placement in RA would offer a better pressure gradient as compared with the IVC, by keeping the tip at the least intrathoracic pressure, as central venous pressures are significantly more than that of the RA.⁸ Hence, the distal catheter was trimmed and resized to appropriate length by endovascular approach.

Endovascular techniques are well established for retrieval and repositioning intravascular catheters. They have also been used as the initial modality for accurate placement of the distal ends of VA shunts, due to better identification of the IJV and cavoatrial junction and real time positioning of the catheter using a minimally invasive approach.⁹

Learning points.

• Accurate placement of ventriculoatrial (VA) shunts is crucial for better long-term results.

• Endovascular approach is well established for endovascular retrieval of dislodged catheters.

• Endovascular approach is a useful technique for accurate placement, repositioning and, in this case, resizing of the distal end of a VA shunt catheter.

Ethics statements

Patient consent for publication

Consent obtained from the parent(s)/guardian(s).