Distal ventriculoperitoneal shunt catheter migration to the right ventricle of the heart - a case report.
The ventriculoperitoneal shunt (VPS) is the most common surgical treatment for hydrocephalus, and the operation has been practiced for the past 60 years. While it has a low complication rate, complications do sometimes occur. Most often, these tend to be mechanical obstructions or infection. Numerous case reports in the literature illustrate the many possible complications seen with the VPS, but it is rare for a portion of a VPS catheter to travel into the chest as this is not a part of the normal course for tubing since it is tunneled to the peritoneal cavity. We present a case where the distal end of a catheter placed in the peritoneum migrated to the heart.
A 34-year-old male presented with reports of gradually worsening headaches. The patient had a prior VPS placement at an outside institution (Figure 1) two years prior. The past medical history was significant for spina bifida and tethered cord, for which he had a lipoma removal and release of tethered cord six months prior presentation. The operation was complicated by a postoperative cerebrospinal fluid leak and development of a pseudomeningocele in the lumbar spine. This led to severe headaches, as well as low back pain and swelling. The VP shunt was then placed for diversion of CSF by an outside neurosurgeon in order to resolve the pseudomeningocele and relieve the pressure in the lumbar cistern, allowing the dural defect to heal. The patient reported good relief of symptoms for eight months, but the headaches returned, leading to presentation in our clinic. A shunt malfunction was suspected at presentation, so a shunt series of plain film X-rays was ordered as part of the initial workup. The X-rays showed a catheter coiled around itself in the thorax without any extension to the abdomen (Figure 1d). A CT scan of the neck and chest showed that the catheter extended through the neck into the right subclavian vein and continued through the right heart to the pulmonary vasculature (Figure 2).
Neurosurgeons frequently see VPS complications. However, thoracic complications are rare, as shunt catheters normally do not enter this area. Intracardiac migration is seen even less often, with only 12 cases reported in the literature.
Taub described supra- and transdiaphragmatic routes for the migration of the peritoneal catheter to the chest. (1) The routes can be distinguished radiographically, as any tubing seen in the abdomen must pass through the diaphragm to enter the thorax. Taub and Lavyne hypothesize that transdiaphragmatic migration occurs either when a catheter erodes the diaphragm or when it passes through the Foramen of Bochadalek or Morgagni. (21,26) Because no portion of the catheter was visible in imaging studies of the abdomen, we decided that the site of entry in the case was supradiaphragmatic.
Morell, the first to describe the migration of a VPS catheter into the heart, proposed two possible ways it might occur. (2) He first postulated that there is iatrogenic damage to a vein when using the shunt passer, with some portion of the distal catheter within the vessel. This may occur when tunneling too deep or too medial in the supraclavicular area. After removal of the shunt passer, a portion of the catheter is left intravenous, and the orthrograde blood flow, combined with negative inspiratory pressure, draws the catheter proximally through the vein and eventually to the heart or pulmonary artery. This seems the most plausible mechanism as 10 of the 12 reported cases describe damage to a jugular vein. Of the 10, seven described passage through the internal jugular vein, which may occur when the catheter is tunneled too deep. The other proposed mechanism was erosion into an adjacent vein by the distal catheter. Once the portion of the catheter is in lumen of the vessel, the same described mechanism of inspiratory pressure coupled with blood flow draws the catheter proximally to the heart.
The diagnosis is easily made with plain films, as in our case, but the surgeon should obtain further imaging for complete operative planning. CT scanning of the neck and chest will reveal the vessel in which the catheter travels, as well as the specific course within the chest cavity. An echocardiogram will show the exact location in the heart, and it will also help rule out thrombus, cardiac perforation, valvular damage, or tamponade. Cardiac rhythm monitoring or an electrocardiogram will show any ectopy if there is a focus due to the catheter.
A review of the literature shows an evolution in the treatment for this specific problem. The patient in the first reported case underwent a thoracotomy and open heart surgery for treatment. Frazier describes a sub-xyphoid pericardial window for direct observation of the heart as the catheter was withdrawn . Fluoroscopic guided removal of the distal catheter and placement in the peritoneal cavity is the most common treatment, but some authors used the assistance of interventional radiology and percutaneous techniques to remove the tubing from the heart.
Imamura and Ruggiero both elected to withdraw the catheter into the right atrium under fluoroscopy, but chose not to reposition the catheter in the peritoneum [4,5]. They used a cervical incision to shorten the distal catheter and left their patients with a ventriculo-atrial (VA) shunt. They point out the advantages of this procedure: a shorter operative time without the need for general anesthesia. However, VA shunts carry the risks ofcardiac insufficiency, cardiac arrhythmias, tamponade, mural thrombi, pulmonary emboli, as well as endocarditis and sepsis in the setting of infection.
This case shows a rare yet dangerous complication of a basic surgical procedure. Migration of a peritoneal catheter into the heart puts the patient at risk for pulmonary emboli, cardiac arrhythmias, sepsis, tamponade, and valvular damage. The diagnosis is easily made with plain films, but CT scanning and an echocardiogram should be part of the complete workup. Treatment options include removing the catheter under fluoroscopic guidance, with assistance of loop snare devices, grasping forceps, and helical baskets per interventional radiology should there be difficulty with the manual retrieval. Moreover, the majority of cases reported in the literature describe the catheter passing intravascular through the external or internal jugular vein. This likely happened because the shunts were passed too medial and too deep, placing the catheter either through or adjacent to these vessels. There does not appear to be a need for more invasive procedures, such as a thoracotomy or pericardial window, given the success and lack of complications with minimally invasive techniques. Perhaps the open surgical procedures should be reserved for more complicated cases not amenable to percutaneous methods. Most importantly, the case report presented demonstrates the need for careful and proper technique in the setting of a basic surgical procedure. Remaining cognizant of the path of the shunt passer and obtaining proper post-operative imaging are the best ways to avoid this complication.
(1.) Taub E, Lavyne MH. Thoracic complications of ventriculoperitoneal shunts: case report and review of the literature. Neurosurgery 1994;34:181-183.
(2.) Morell RC, Bell WO, Hertz GE, et al. Migration of a ventriculoperitoneal shunt into the pulmonary artery. J Neurosurg Anesthesiol 1994;6:132-134.
(3.) Frazier JL, Wang PP, Patel SH, et al. Unusual migration of the distal catheter of a ventriculoperitoneal shunt into the heart: case report. Neurosurgery 2002;51:819-822.
(4.) Imamura H, Nomura M. Migration of ventriculoperitoneal shunt into the heart-case report. Neurol Med-Chir (Tokyo) 2002;42:181183.
(5.) Ruggiero C, Spennato P, De Paulis D, et al. Intracardiac migration of the distal catheter of ventriculoperitoneal shunt: a case report. Childs Nerv Syst 2010;26:957-962.
Marc Manix, MD; Anthony Sin, MD; Anil Nanda, MD, MPH, FACS
Drs. Manix, Sin, and Nanda are with the Louisiana State University Health Sciences Center-Shreveport's Department of Neurosurgery.
|Printer friendly Cite/link Email Feedback|
|Author:||Manix, Marc; Sin, Anthony; Nanda, Anil|
|Publication:||The Journal of the Louisiana State Medical Society|
|Article Type:||Case study|
|Date:||Jan 1, 2014|
|Previous Article:||Treatment of submucous cleft palate with selective use of the Furlow Z-palatoplasty.|
|Next Article:||Malposition of a hemodialysis catheter in the accessory hemiazygos vein.|