Clinical Picture:
The majority of cases are asymptomatic.
Few case series and case reports reported associated symptoms ranging between 5.6% - 32%.
These may include limb swelling,
claudication,
chest pain from pulmonary embolism,
dyspnea or cardiac arrhythmias.
Imaging
Obtaining proper history including the size,
shape and suspected location of the lost IFB is important before imaging in order to select the appropriate imaging modality and body part to be imaged.
Plain radiographs are typically the first step when an IFB is suspected,
where some of the lost IFB are poorly visualized due to small size and poor x-ray attenuation..
Increasing the pulse/frame rate or using Computed Tomography (CT) could help localize the lost IFB.
CT scans can be very helpful for more precise localization and identifying objects not seen on plain radiographs.
MRI has been used when the IFB is MRI compatible.
Removal techniques and devices
Loop snares:
Usually the device of choice.
The modern designs allow the loop to emerge at 90°to the catheter enhancing manipulation and IFB capture.
They vary in size from 2 to 35 mm and available for use in 2.3F to 6F delivery platforms.
All forms of loop snares are modeled on the use of a moveable Nitinol wire loop passing through a catheter.
Excellent safety profile and relatively atraumatic.
(Fig 1).
Fig. 1: A: Amplatz gooseneck snare (ev3)
B: Trefoil En-Snare (Merit Medical)
References: Woodhouse JB, Uberoi R. Techniques for Intravascular Foreign Body Retrieval. Cardiovasc Intervent Radiol (2013) 36:888–897
Proximal grab technique:
The most common technique used when using a snare.
A snare loop equal or slightly smaller than the vessel diameter is used.
Once in position,
the snare catheter is withdrawn allowing the snare to open and then advanced to encircle the IFB.
The loop is then closed by advancing the snare sheath.
A free end on the IFB is needed for this technique in order for the loop to have something to grasp.
A shaped catheter such as a pigtail,
SOS,
Omniflush,
or balloon catheter may be used to tilt or displace the IFB to expose a free end for the snare.
(Fig 2).
Fig. 2: A and B: When a snare is used to grasp an object, it tends to pull that object perpendicular to the axis of the catheter/constraining vessel.
C: It is better to grasp the object at one end so that there is a natural trailing edge that helps keep objects aligned with the vessel axis. This is the most basic use of a snare.
References: Woodhouse JB, Uberoi R. Techniques for Intravascular Foreign Body Retrieval. Cardiovasc Intervent Radiol (2013) 36:888–897
Distal wire grab technique:
This technique can be used if a guide wire can be passed through the IFB.
A snare is used to track alongside and past the IFB then the snare is used to capture the distal end of the guidewire so the FB will be contained between the wire and snare.
This technique keeps the FB aligned parallel to the vessel axis.
(Fig 3).
Fig. 3: A and B: The guide wire is passed through the foreign body (FB). The snare is passed distally alongside the FB and captures the guide wire distally. The FB is maintained in alignment with the vessel axis.
References: Woodhouse JB, Uberoi R. Techniques for Intravascular Foreign Body Retrieval. Cardiovasc Intervent Radiol (2013) 36:888–897
Coaxial snare technique:
This technique uses a guide wire and a snare to reduce the angulation between the foreign body,
the snare,
and the sheath. It is used only with tubular foreign bodies,
were the goal is to pass a guide wire through the lumen of the IFB.
The snare is then positioned around the guide wire which then becomes a monorail to guide the snare loop distally.
At the proximal pole of the tubular IFB,
the snare loop is opened and is used to capture the IFB and the guide wire together.
The guidewire,
IFB,
and snare are then retracted as a unit into the sheath.
This technique allows a tubular IFB to be retrieved without folding over the object,
thus permitting a smaller profile vascular access point.
(Fig 4).
Fig. 4: A stiff guide wire through the FB helps maintain the axis of the construct along the line of the guide catheter and constraining vessel.
References: Woodhouse JB, Uberoi R. Techniques for Intravascular Foreign Body Retrieval. Cardiovasc Intervent Radiol (2013) 36:888–897
Lateral grasp technique:
This technique deploy the snare distal to the IFB and opened widely.
A rigid guide wire is passed around the other side of the IFB and then through the snare loop,
then it closes and grasps the guide wire.
Both guide wire and snare catheter pinch grip the IFB between their shafts.
(Fig 5).
Fig. 5: A and B: Lateral grasp technique demonstrated with a stent. The wire and the snare pass on either side of the FB and the wire need not pass through the FB. The guide catheter is then advanced to close the construction and entrap the FB.
References: Woodhouse JB, Uberoi R. Techniques for Intravascular Foreign Body Retrieval. Cardiovasc Intervent Radiol (2013) 36:888–897
Dormia Basket:
It is made from two loops of Nitinol wire spirals that unfurl on deployment,
decreasing the risk of vessel wall damage.
A sheath is used to open and close the basket and can easily be used by a single operator with one hand.
It can be passed down a narrow guide catheter and access small-caliber vessels.
It can also unfurl providing a wide loop that is advantageous to encircling the IFB.
It is used to remove virtually all IFBs by itself or in combination with a reverse-curve catheter used to mobilize the IFB to a point where it can be more easily captured.
Its drawbacks are being difficult to guide and that some of them have a rigid tip that poses a risk of endothelial wall damage.
(Fig 6).
Fig. 6: Dormia Basket
References: Woodhouse JB, Uberoi R. Techniques for Intravascular Foreign Body Retrieval. Cardiovasc Intervent Radiol (2013) 36:888–897
Small balloon catheter technique:
This technique is useful in retrieval of lost stents.
The most important step is to select an appropriate size retrieval balloon.
It necessitates that a guide wire traverses through the IFB and used to guide a noncompliant balloon catheter within or distal to the lost IFB.
The balloon is then passed through the IFB,
inflated with low pressure and then gently pulled back.
This technique can also be used in conjunction with a loop snare to capture a stent.
(Fig 7).
Fig. 7: Small balloon technique used in conjunction with a loop snare to capture a stent:
An appropriately sized balloon is used over a guide wire through the stent.
A snare can be railroaded over the balloon to the proximal end of the stent.
Once in position, the balloon is inflated to bring the loop snare flush with the presenting aspect of the stent.
The snare loop is then advanced to encircle the stent.
References: Woodhouse JB, Uberoi R. Techniques for Intravascular Foreign Body Retrieval. Cardiovasc Intervent Radiol (2013) 36:888–897
Guide wire techniques:
Some IFBs have been successfully retrieved only utilizing a guide wire.
That could be done by using the guide wire with a catheter to construct a homemade loop snare,
making a hairpin trap by folding the distal end of a narrow guide wire or passing one guide wire through the lumen of a stent and another stiffer one through the stent struts performing the Two-wire Technique,
were they are rotated around each other and are used to apply a pincer like grip around the lost stent.
Intravascular Retrieval Forceps:
They come in a range of sizes from 12F to 3F and do not require a free edge as in snare.
Though they carry a higher risk of vessel wall damage and perforation.
(Fig 8).
Fig. 8: A & B: Alligator retrieval forceps (Cook Medical and Ev3)
C: Myocardial biopsy forceps (Cook)
References: Woodhouse JB, Uberoi R. Techniques for Intravascular Foreign Body Retrieval. Cardiovasc Intervent Radiol (2013) 36:888–897
Object removal:
Once control of the IFB has been obtained,
it must be removed from the body.
The IFB can be pulled into sheath,
directly through entry tract,
or pulled to the percutaneous entry site,
and a cut-down can be performed.
Outcomes and complications
In most case series,
IFB explantation is associated with 100 % survival.
Complications in treated cases include groin hematoma,
vessel injury or perforation,
arterial spasm,
thrombosis,
arrhythmias and flail tricuspid valve.
Case presentation:
Case 1:
A 46 year-old female with fractured subclavian port catheter fragment in the right atrium/ventricle.
(Fig 9).
Fig. 9: A: The catheter fragment (arrows) is lodged between the lateral right atrial and medial right ventricular showing no free end. A Multi-snare device was advanced into the right atrium via the right groin.
B: A multipurpose curved sheath was advanced into the right atrium and oriented toward the lateral wall of the right atrium. The tip of the catheter was then snared (dotted circle) and withdrawn into the sheath.
Case 2:
Wire in the SVC through IVC and left iliac vein. (Fig 10).
Fig. 10: A: Radiograph demonstrating a loose wire (arrows) from prior femoral central line placement extending from the left iliac vein into the IVC.
B: A snare (arrow) was advanced through a 7-French sheath.
C: The tip of the wire was snared (dotted circle) and withdrawn through the left femoral vein.
Case 3:
A 51 year-old female with a fractured right subclavian port due to impingement syndrome.
( Fig 11,12)
Fig. 11: Case 3,A: Radiograph of the chest demonstrates a fractured right subclavian vein port with the distal catheter fragment located in the right atrium (small arrows). A previously placed left peripherally inserted central catheter (PICC) was noted with its distal tip located in the superior vena cava (large arrow).
Fig. 12: Case 3,B: A Goose neck snare device was used to retrieve the fragmented catheter through a right common femoral vein access site.
Case 4:
A 39-year-old female with fractured port.
( Fig 13,
14).
Fig. 13: Case 4, A: Radiograph demonstrated the distal end of the catheter to be located within the right ventricle. Goose-neck snare system was unable to snare the proximal end of the catheter which was against the medial wall of the left brachiocephalic vein.
B: A pigtail catheter was utilized to mobilize the proximal end of the catheter into the SVC.
Fig. 14: Case 4, C and D: The catheter was then snared by the goose-neck snare and removed from the heart.
Case 5:
A 34 years old female with a fractured catheter fragment in the pulmonary artery following removal of a Ventriculo-Atrial shunt.
( Fig 15,
16).
Fig. 15: case 5 ,A: Radiograph showing a catheter fragment (arrows) in the main and right pulmonary artery.
B: After accessing the main pulmonary artery, the proximal end of the catheter fragment was snared using a Goose-neck snare.
Fig. 16: Case 5, C: Radiograph showing fractured catheter fragment (dotted circle) snared and pulled through the IVC.