Complications of central venous port systems: a pictorial review

Abstract

Central venous port devices are indicated for patients, who need long-term intravenous therapy. Oncologic patients may require intermittent administration of chemotherapy, parenteral nutrition, infusions, or blood transfusions. A venous port system is composed of a port chamber attached to a central catheter, which is implanted into the central venous system. The subcutaneous location of the catheter chamber improves the patients' quality of life and the infection rate is lower than in non-totally implantable central venous devices. However, proper implantation, use, and care of a port system are important to prevent short- and long-term complications. Most common early complications (< 30 days) include venous malpositioning of catheter and perforation with arterial injury, pneumothorax, hemothorax, thoracic duct injury, or even cardiac tamponade. Delayed complications include infection, catheter thrombosis, vessel thrombosis and stenosis, catheter fracture with extravasation, or fracture with migration or embolization of catheter material. Radiologic imaging has become highly relevant in intra-procedural assessment and postoperative follow-up, for detection of possible complications and to plan intervention, e.g., in case of catheter migration. This pictorial review presents the normal imaging appearance of central venous port systems and demonstrates imaging features of short- and long-term complications.

Keywords: Complication; Malposition; Perforation; Port; Thrombosis.

Fig. 1

Normal position of implanted port system. a Chest radiograph shows the tip of the venous catheter projecting onto the intersection with the intermediate bronchus, which suggests position in the SVC. b Coronal MDCT reformation (soft tissue window and minimum intensity projection of lung window) shows that intersection of the tip with intermediate bronchus indicates correct position in the SVC. c, d Flow confirmation study (c) before and (d) after injection of contrast. The port chamber is completely opacified (arrow), the venous tube does not show leakage, and contrast material exits freely at the tip flowing in antegrade direction (small arrows)

Fig. 2

Common venous malpositioning. a The venous catheter, implanted via the subclavian vein, enters the contralateral brachiocephalic vein (arrow). b Loop formation in the subclavian vein. c–e Malpositioning in the mammarian vein due to occlusion of the SVC. c PA chest film shows normal course of the catheter, which had been implanted into the internal jugular vein. d However, the lateral projection shows an abnormal anterior course. e Sagittal MIP CT reconstruction confirms malpositioning into the internal mammary vein

Fig. 3

a Malpositioning in a persistent left superior vena cava: on a chest film, this could be confused with arterial malpositioning in the aortic arch via the left subclavian artery. b Unenhanced CT shows the tip of the catheter in the SVC, which drains into the right atrium

Fig. 4

Malpositioning in the heart. a PA chest radiography shows a very long, looping catheter, which had not been shortened by the surgeon during the procedure. The tip is projecting onto the right heart (arrow). b Lateral chest radiograph shows typical anterior bending (arrows) due to position in the right ventricle. c In this example, the catheter tip is not clearly seen, but seems to be placed too deep (arrows). d Lateral projection shows a straight course, with the tip in the inferior vena cava (arrow). e Five weeks later, a follow-up film now shows posterior curving of the catheter. f Contrast-enhanced MDCT (MIP reconstruction) confirms displacement of the catheter into the coronary sinus

Fig. 5

Arterial malpositioning of an interventionally placed port system. DSA shows placement into the subclavian artery close to the origin of the vertebral artery (arrow)

Fig. 6

Extravascular malpositioning. a Intraoperative fluoroscopy shows the catheter projecting above the clavicles, which is not in line with an intravascular position (in the brachiocephalic vein). b Port system was subsequently used for several weeks. Follow-up chest radiograph shows increasing pleural effusions. Malposition of the catheter was reported. c, d Subsequently a flow confirmation study was performed, which shows extravascular collection of contrast (star) and some contrast material reflux into the internal jugular vein (large arrow), the subclavian vein (small arrow), as well as along the catheter into cervical veins (arrowhead). The catheter has an extravascular course and perforated the contralateral venous angle, with chemotherapy infusions partly entering the venous systems, partly filling up the pleural space

Fig. 7

Pneumothorax. a Three days after correct placement of port system, the patient complained of dyspnea. Chest radiograph shows a large right pneumothorax. b Regular placement of a port system on the right side. There is a contralateral pneumothorax from unsuccessful attempts on the left side, which were not mentioned in the referral

Fig. 8

Malpositioning in the pleural space. a Postoperative chest radiograph shows an abnormal course of the venous catheter, which crosses the midline. A small apical pneumothorax is noted (arrow). b Subsequently, a MDCT was performed, which shows the venous line in the pleural space (arrow) and a pneumothorax

Fig. 9

a Twisting of port chamber (arrow) results in the inability to puncture the chamber. b, c Thrombosis of port chamber in another patient with increased flow resistance. Pre-contrast image shows the chamber, which only incompletely and marginally fills with contrast (small arrows). Note that the tube is completely opacified as proof of adequate injection (large error)

Fig. 10

Catheter pinch-off, disconnection, and fracture. a, b Catheter pinch-off with subsequent fracture. a Chest radiographs show a slight kink and pinch-off of the catheter at the thoracic inlet (between clavicle and first rib). b Five months later, a flow confirmation study shows extravasation at the thoracic inlet (due to fracture). Incidental note is made of the catheter tip in the right atrium. c Catheter disconnection in another patient: the entire catheter has gone off and embolized in the heart (large arrow). Only the subcutaneous fibrous tunnel is opacified with contrast (small arrows). d–f Fracture of catheter and percutaneous removal. d After explantation of a port system, a catheter fragment is still visible (arrow). e Via a right femoral vein access a snare is advanced toward the catheter tip. f After pulling the snare tight around the catheter (arrow), it can be safely removed

Fig. 11

Thrombosis. a Flow confirmation study shows contrast backflow around the catheter. It is not clear, whether the catheter is in an intravascular position. b CT was subsequently performed, which shows the tip of the catheter too high in the brachiocephalic vein with venous thrombosis and development of multiple collaterals. c In another patient with increased resistance during infusions, flow confirmation study shows a fibrin sheath around the catheter (arrows). Infusion of thrombolytics (rTPA) restored good flow of the system. d In another patient, incidental finding of a thrombus at the catheter tip detected during contrast-enhanced MDCT follow-up