A knotty problem

Percutaneous fluoroscopic removal of a knotted Swan?Ganz catheter in a patient with a persistent left-sided superior vena cava

Knotting of intravascular catheters is an uncommon but a well-recognized occurrence. The Swan-Ganz catheter (SGC) is the one that knots most commonly. A case of a knotted SGC is described in a patient with a persistent left-sided superior vena cava, and we propose that the presence of a left-sided superior vena cava is a risk factor for knot formation not previously reported. We review the published work on the risk factors for knot formation and on the techniques used to remove knotted SGC. We describe a technique using a gooseneck snare and Omni Flush catheter (Angiodynamics, Queensbury, NY, USA) to loosen and untie a knotted SGC.

Removal of knotted intravascular devices. Case report and review of the literature

OBJECTIVE

to review published reports on knotted intravascular devices/catheters.

METHOD

report of two cases and systematic review of the literature.

RESULTS

a total of 113 reported cases of knotted intravascular devices/catheters were located. Pulmonary artery catheters (Swan-Ganz) were responsible for more than two thirds of the total reported intravascular knots. In 62% (70/113) of the cases withdrawal of the knotted catheters was achieved successfully with different interventional radiological techniques, avoiding the need for surgical exploration. In 32% (36/113) of the patients surgical removal was favoured. Capture with one of the interventional techniques and pulling down the knot into an easily accessible vein to be removed through an open venotomy, was the most common surgical procedure. However, in five cases, an open cardiotomy was required. In seven cases the patient's condition was critical and precluded any surgical procedure, so the knotted catheter was left in situ. The mortality of this event was 8% (9/113).

CONCLUSIONS

interventional radiological techniques have largely replaced open surgical removal. Knotted catheters may need to be surgically removed when (a) the knot is large in size with many loops, or (b) intracardiac fixing of the knot is encountered.