Transhepatic venous catheters for hemodialysis

Purpose

To describe our experience with the technique of transhepatic venous access for hemodialysis and to evaluate its functionality and complications.

Patients and methods

From March 2012 till October 2012, 23 patients with age ranging from 12 to 71 years old having end-stage renal disease (ESRD) were included in our study and were subjected to transhepatic venous catheter insertion. In 21 patients there were not any remaining patent peripheral venous accesses. In 2 patients there were only a last one venous access needed to be preserved. Thus, it was decided to make THVA. In all the 23 patients the indication was palliative due to inoperability which was because of inability to insert an arterio-venous graft or making another arterio-venous fistula. Complications were evaluated and calculated in terms of number of procedures, infection, dislodgement and outcome; in terms of disfunctionality of the catheter.Follow-up was performed by monitoring the catheter dialysis rate in each session, abdominal ultrasonography, fluoroscopy or CT. Mean survival time and median survival time from the start of treatment were calculated using Kaplan–Meier method.

Results

Twenty-three patients required a single transhepatic access procedure. Because of catheter dislodgment, two patients required a second access placement procedure, which resulted in a total of 25 separate transhepatic access sites in 23 patients. Technical success was achieved in 22 procedures. Functionality success was achieved in 20 patients. Functionality failure occurred in 3 patients.The trans-hepatic catheters stayed in place between 90 and 300 days. Complications occurred in 14 patients.

Conclusion

Based on our findings, transhepatic hemodialysis catheters have proven to achieve good long-term functionality. A high level of maintenance is required to preserve patency, although this approach provides remarkably durable access for patients who have otherwise exhausted access options.     

Catheter Fracture and Embolization Associated With Arm Implantation of the Cook Vital Port

Purpose

To determine the frequency of arm port catheter fracture and embolization related to the Cook Vital Port Mini Titanium.

Materials and Methods

A retrospective audit of our Cerner Radiology Information System was performed between June 1, 2006, and June 30, 2011, to determine the number of Cook arm venous ports implanted and the frequency of foreign body retrievals related to catheter fracture for these arm ports.

Results

A total of 691 arm implantations of the Cook Vital Port during the 5-year time frame were analysed. Eleven of these patients (1.6%) required intravenous foreign body retrieval in the interventional radiology suite related to catheter fracture and embolization. Three of these fractured catheters were retrieved from the peripheral venous system upstream of the pulmonary circulation, whereas 8 embolized to the pulmonary arteries. All were successfully extracted with an intravenous snare by interventional radiology.

Conclusion

We discovered a 1.6% frequency of catheter fracture and embolization associated with arm implantation of the Cook Vital Port. All the catheters fractured at the vein entry site and did not detach from the port housing. The cause for catheter fracture and embolization is uncertain. Pulmonary embolization of the fractured catheters puts the patients at risk for possible further complications. No patients had ancillary complications related to catheter embolization or to catheter extraction procedures. Further investigation is required in an attempt to determine the circumstances that may result in catheter fracture and embolization related to this venous access device.     

CT-Guided Superior Vena Cava Puncture: A Solution to Re-Establishing Access in Haemodialysis-Related Central Venous Occlusion Refractory to Conventional Endovascular Techniques

Purpose

The purpose of this technical note is to demonstrate the novel use of CT-guided superior vena cava (SVC) puncture and subsequent tunnelled haemodialysis (HD) line placement in end-stage renal failure (ESRF) patients with central venous obstruction refractory to conventional percutaneous venoplasty (PTV) and wire transgression, thereby allowing resumption of HD.

Methods

Three successive ESRF patients underwent CT-guided SVC puncture with subsequent tract recanalisation. Ultrasound-guided puncture of the right internal jugular vein was performed, the needle advanced to the patent SVC under CT guidance, with subsequent insertion of a stabilisation guidewire. Following appropriate tract angioplasty, twin-tunnelled HD catheters were inserted and HD resumed.

Results

No immediate complications were identified. There was resumption of HD in all three patients with a 100 % success rate. One patient’s HD catheter remained in use for 2 years post-procedure, and another remains functional 1 year to the present day. One patient died 2 weeks after the procedure due to pancreatitis-related abdominal sepsis unrelated to the Tesio lines.

Conclusion

CT-guided SVC puncture and tunnelled HD line insertion in HD-related central venous occlusion (CVO) refractory to conventional recanalisation options can be performed safely, requires no extra equipment and lies within the skill set and resources of most interventional radiology departments involved in the management of HD patients.

     

Safety and feasibility in highly concentrated contrast material power injections for CT-perfusion studies of the brain using central venous catheters

Introduction

CT perfusion studies play an important role in the early detection as well as in therapy monitoring of vasospasm after subarachnoid hemorrhage. High-flow injections via central venous catheters are not recommended but may sometimes be the only possibility to obtain high-quality images.

Materials and methods

We retrospectively analyzed our data for CT perfusions performed with power injection of contrast material with an iodine concentration of 400 mg/ml via the distal 16G lumen of the Arrow three and five lumen central venous catheter with preset flow rates of 5 ml/s.

Results

104 examinations with central venous catheters were evaluated (67 with five lumen and 37 with three lumen). No complications were observed. Mean flow rates were 4.4 ± 0.5 ml/s using the three lumen catheter and 4.6 ± 0.6 ml/s using the five lumen catheter respectively. The mean injection pressure measured by the power injector was 200.7 ± 17.5 psi for the three lumen central venous catheter and 194.5 ± 6.5 psi for the five lumen catheter, respectively.

Conclusion

Following a strict safety protocol there were no complications associated with power injections of contrast material containing 400 mg iodine/ml with preset flow rates up to 5 ml/s via the distal 16G lumen of the Arrow multi-lumen central venous catheter. However, since power-injections are off-label use with Arrow central venous catheters, this procedure cannot be recommended until potential safety hazards have been ruled out by the manufacturer.     

Percutaneous retrieval of dislodged totally implantable central venous access system in 92 cases: experience in a single hospital

Objective

To investigate the clinical presentation of dislodged totally implantable central venous access system (central venous port-catheter) fragments and the efficacy and safety of percutaneous retrieval of them in our hospital.

Materials and methods

Ninety-two cancer patients, mean age of 53.8 years old with 51.1% male, were enrolled from January 2005 to March 2007. They were referred to our catheterization laboratory for retrieval of fractured central venous port-catheter in our hospital. All patients were followed in the outpatient department for at least 1 month after surgical insertion. The characteristics of disrupted central venous port-catheter were recorded. The procedure-related clinical condition was evaluated.

Results

The most common presentation of central venous port-catheter dislodgement is irrigation resistance to infusion (51/92). The most common location of fractured fragments is between superior vena cava and right atrium (i.e. proximal end remained in superior vena cava and distal end in right atrium) (22/92). The most common fracture site of the catheter is at the anastomosis between injection port and catheter (77/92). The retrieval set used mostly is loop snare. The success rate of the percutaneous retrieval of dislodged fragment was 97.8% and the complication rate was 3.3% only.

Conclusion

The faulty connection between catheter and injection port contributes mainly to dislodgement of central venous port-catheter. Percutaneous retrieval of dislodged catheter is a highly successful, safe and efficient method.     

Percutaneous image-guided aspiration versus catheter drainage of abdominal and pelvic collections

Purpose

Intra abdominal and pelvic fluid collection is a serious problem that requires drainage. The goal of our study was to report our experience and evaluate the feasibility, safety and outcome of percutaneous image-guided aspiration versus catheter drainage of abdominal and pelvic collections.

Patients and methods

This is a retrospective study of 84 patients (45 males and 39 females of mean age 45.1 + 16.9 years) who have intra abdominal or pelvic collections and have a good coagulation profile. Small (<5 cm) collections were treated by aspiration. Continuous catheter drainage was applied to failed aspirations or large collection.

Results

112 Drainage procedures were carried out in 84 patients guided by either ultrasound or CT. Aspirations of 31 collections were carried out in 22 patients, and 81 catheters (8–10 French) were inserted in 66 patients. Four patients had both aspirations and catheters. The collections were either sterile or pus. Median diameter of aspirated collections was 4.2 cm (3–5 cm) compared to 7.2 cm (6–12 cm) of those treated by catheters P < 0.05. Technical success was 100% in both aspiration and catheter insertion using the Seldinger technique but it was 87% with the trocar technique. Clinical success rate for aspiration was 94% (n = 29) but increased to 100% after catheter insertion and that of catheter was 95%. No major complications were encountered.

Conclusion

Image-guided drainage of abdominal and pelvic collections is safe and effective and can avoid surgery in selected patients. Aspiration should be tried before catheter insertion. Careful catheter selection for trochar technique is important.     

Coil embolization of internal mammary artery injured during central vein catheter and cardiac pacemaker lead insertion

Purpose

This study describes several cases of endovascular coil embolization of the proximal internal mammary artery injured by blind approach to the subclavian vein for central venous catheter or pacemaker lead insertion.

Materials and methods

We conducted a retrospective analysis of five patients with iatrogenic arterial lesions of the internal mammary artery (IMA). The lesions occurred in three patients from a puncture of the subclavian vein during insertion of a central venous catheter and in two patients from a puncture of the subclavian vein for insertion of a pacemaker lead. Four patients had acute symptoms of bleeding with mediastinal hematoma and hematothorax and one patient was investigated in a chronic stage. A pseudoaneurysm was detected in all five patients. All four acute and hemodynamic unstable patients required hemodynamic support.

Results

In all patients, embolization was performed using a coaxial catheter technique, and a long segment of the IMA adjacent distally and proximally to the source of bleeding was occluded with pushable microcoils. In one patient, additional mechanically detachable microcoils were used at the very proximal part of the IMA.Microcoil embolization of the IMA was successful in all patients, and the source of bleeding was eliminated in all patients.

Conclusion

Transarterial coil embolization is a feasible and efficient method in treating acute bleeding and pseudoaneurysm of the IMA and should be considered if mediastinal hematoma or hemathorax occurs after blind puncture of the subclavian vein.     

Evaluation of failing hemodialysis fistulas with multidetector CT angiography: comparison of different 3D planes

Purpose

To evaluate failing hemodialysis fistula complications using 16-detector MDCTA, and to assess the accuracies of different 3D planes.

Materials and methods

Thirty patients (16 men, 14 women, aged 27–79 years) were referred for hemodialysis access dysfunction. Thirty-one MDCTA exams were done prior to fistulography. For MDCTA, contrast was administered (2 mL/kg at 5 mL/s) via a peripheral vein in the contralateral arm. Axial MIP, coronal MIP, and VRT images were constructed. Venous complications were evaluated on axial source images, on each 3D plane, and on all-planes together. Results were analyzed using McNemar test.

Results

Axial MIP, VRT and all-planes evaluations were most sensitive for fistula site detection (93%). Coronal MIP had the highest sensitivity, specificity and accuracy (35%, 96%, and 85%, respectively) for detecting venous stenosis. VRT and all-planes had the highest sensitivity and accuracy for detecting aneurysms (100%). All-planes and axial MIP were most sensitive for detecting venous occlusion (61% and 54%). Comparisons of detection frequencies for each venous pathology between the five categories of MDCTA revealed no significant differences (P > 0.05). MDCTA additionally showed 3 partially thrombosed aneurysms, 4 anastomosis site stenosis and 12 arterial complications.

Conclusion

MDCTA overall gives low sensitivity for detection of central vein stenosis and moderate sensitivity for occlusion. For most pathology, all-planes evaluation of MDCTA gives highest sensitivity and accuracy rates when compared to other planes. For venous stenosis and occlusion, MDCTA should be considered when ultrasonography and fistulography are inconclusive. MDCTA is helpful in identifying aneurysms, collaterals, partial venous thromboses and additional arterial, anastomosis site pathologies.     

Use of the femoral vein as insertion site for tunneled hemodialysis catheters

PURPOSE: To determine the outcome of tunneled hemodialysis catheters inserted through the common femoral vein. MATERIALS AND METHODS: From April 2000 to June 2003, 33 consecutive patients had 86 tunneled hemodialysis catheters inserted through the femoral vein. There were 14 male and 19 female patients with a mean age of 56 years. Seventeen patients had bilateral central venous and/or superior vena cava (SVC) occlusions, 12 patients had unilateral central venous occlusions and were to receive contralateral arteriovenous fistulas or arteriovenous polytetrafluoroethylene grafts, and 4 patients received femoral catheters for other reasons. The technical success, complications, and clinical outcomes of these procedures were retrospectively evaluated. RESULTS: All procedures were technically successful. Fifty-seven catheters were inserted into the right femoral vein and 29 into the left femoral vein. This included 25 catheter exchanges in 13 patients. Two patients developed thigh hematomas. Follow-up data were available for 68 catheters; mean follow-up period was 51 days with a total of 3,484 catheter days. The catheter-related infection rate was 6.3 per 1,000 catheter days; 22 catheters were removed for infection. Eighteen catheters were removed because of poor blood flows (<200 mL/min). Thirteen catheters were removed because they had become retracted. Primary catheter patency was 44% at 1 month. CONCLUSIONS: The femoral vein provides an alternative access site for insertion of tunneled hemodialysis catheters when conventional sites are not available. However, tunneled femoral hemodialysis catheters have low primary patency rates and significant complications. Catheter retraction is a unique and common problem.     

Combined ultrasound and fluoroscopy guided port catheter implantation—High success and low complication rate

Purpose

To evaluate peri-procedural, early and late complications as well as patients’ acceptance of combined ultrasound and fluoroscopy guided radiological port catheter implantation.

Materials and methods

In a retrospective analysis, all consecutive radiological port catheter implantations (n = 299) between August 2002 and December 2004 were analyzed. All implantations were performed in an angio suite under analgosedation and antibiotic prophylaxis. Port insertion was guided by ultrasonographic puncture of the jugular (n = 298) or subclavian (n = 1) vein and fluoroscopic guidance of catheter placement. All data of the port implantation had been prospectively entered into a database for interventional radiological procedures. To assess long-term results, patients, relatives or primary physicians were interviewed by telephone; additional data were generated from the hospital information system. Patients and/or the relatives were asked about their satisfaction with the port implantion procedure and long-term results.

Results

The technical success rate was 99% (298/299). There were no major complications according to the grading system of SIR. A total of 23 (0.33 per 1000 catheter days) complications (early (n = 4), late (n = 19)) were recorded in the follow-period of a total of 72,727 indwelling catheter days. Infectious complications accounted for 0.15, thrombotic for 0.07 and migration for 0.04 complications per 1000 catheter days. Most complications were successfully treated by interventional measures. Twelve port catheters had to be explanted due to complications, mainly because of infection (n = 9). Patients’ and relatives’ satisfaction with the port catheter system was very high, even if complications occurred.

Conclusion

Combined ultrasound and fluoroscopy guided port catheter implantation is a very safe and reliable procedure with low peri-procedural, early and late complication rate. The intervention achieves very high acceptance by the patients and their relatives.     

Hepatic artery-targeting guidewire technique during transjugular intrahepatic portosystemic shunt

Objective

This study evaluated the feasibility and safety of the transjugular intrahepatic portosystemic shunt (TIPS) procedure using the hepatic artery-targeting guidewire technique for the puncture step.

Methods

We retrospectively reviewed 11 consecutive patients (5 men and 6 women, aged 46–76 years (mean 64 years)) with portal hypertension in whom the TIPS procedure was performed. As the first step in the TIPS procedure in all cases, a micro-guidewire was inserted into the hepatic arterial branch accompanying the portal venous branch through a microcatheter coaxially advanced from a 5-French catheter positioned in the coeliac or common hepatic artery. At the puncture step, the tip of the metallic cannula was aimed 1 cm posterior to the distal part of this micro-guidewire, after which the TIPS procedure was performed. Success rate, number of punctures and complications were evaluated.

Results

The TIPS procedure was successfully performed in all 11 patients. The mean number of punctures until success in entering the targeted portal venous branch was 5 (range 1–14). In 3 patients (27%), the right portal venous branch was entered at the first puncture attempt. The hepatic artery was punctured once in one patient and the bile duct was punctured once in another patient. No serious procedure-induced complications occurred.

Conclusion

The TIPS procedure can be accomplished safely, precisely and relatively easily using the hepatic artery-targeting guidewire technique.Transjugular intrahepatic portosystemic shunt (TIPS) placements have continued to increase since the first such procedure was performed in 1988 [1]. Currently, this procedure is accepted as an effective treatment for the complications of portal hypertension, such as variceal bleeding [2] and intractable ascites [2^,3]. In many institutions, including ours, however, this procedure is rarely performed and it might be difficult to maintain the necessary skills.During the TIPS procedure, the puncture from the proximal portion of the hepatic vein (usually a right hepatic vein) to the proximal portion of a branch of the intrahepatic portal vein (usually the right portal vein) is the most important and difficult step [1^,2]. In 1994, Matsui et al [4] introduced a simple technique to assist in this puncture step. This technique was aided by a targeting guidewire in the hepatic arterial branch accompanying the portal venous branch to be punctured. To our knowledge, there has been no subsequent literature on the use of this simple technique, which we have adopted in our institution. This study evaluated the application of the hepatic artery-targeting guidewire technique for the puncture step of the TIPS procedure. We also assessed the occurrence of procedure-induced complications in order to clarify the value of this technique to inexperienced or infrequent operators such as those in our institution.     

Clinical benefit of power-injectable port systems: a prospective observational study

Objective

To prospectively evaluate the clinical benefit of a central venous port system, which is approved for contrast media injection during contrast enhanced computed tomography.

Materials and methods

At a university teaching hospital, 98 patients (59 female, 39 male; median age 61.7 years; range 23–83) had a power-injectable central venous port catheter system implanted. All implantations were performed under ultrasonographic and fluoroscopic guidance by interventional radiologists. Procedure related immediate (up to 24 h after implantation), early (<30 days after implantation) and late complications were documented. The frequency of port system use for contrast enhanced computed tomography scans was also considered. Any port capsule migration was assessed indirectly by determining the catheter tip position. The intended follow-up period was 180 days.

Results

An overall complication rate of 0.69 for 1,000 catheter days in 78 evaluated ports was recorded (12 ports affected, 15.4%). During the observational period, 40 of 104 contrast enhanced computed tomography scans were performed utilizing the port for contrast media administration (38.5%). 30 catheter tip retractions of more than 3 cm were observed in 82 patients (36.6%). Overall, tip dislocations were statistically more frequent in the female subgroup.

Conclusion

The complication rate found in this study is comparable to those, which have been published for standard port systems. The utilization of the device for contrast media injection during contrast enhanced computed tomography scans should be increased. Finally, the port capsule has to be carefully positioned and fixed to prevent migration.     

Concurrent Central Venous Stent and Central Venous Access Device Placement Does Not Compromise Stent Patency or Catheter Function in Patients with Malignant Central Venous Obstruction

Purpose

To determine if concurrent placement of a central venous stent (CVS) and central venous access device (CVAD) compromises stent patency or catheter function in patients with malignant central venous obstruction.

Radiologic placement of central venous catheters: rates of success and immediate complications in 3412 cases.

OBJECTIVE: To determine the success and immediate complication rates associated with 3412 central venous catheter placements performed in an interventional radiology suite. METHODS: Success and immediate complication rates were prospectively recorded for 3412 consecutive patients who had central venous catheters radiologically placed at a tertiary care centre between July 1993 and October 2000. The indication for placement and the insertion site were also recorded. RESULTS: The most common indication for both short- and long-term venous access was hemodialysis, and the right internal jugular vein was the most common site for catheter insertion. Placement was successful for 98.8% of tunnelled lines and 99.3% of temporary catheters. The rate for immediate complications (including pneumothorax, air emboli, bleeding and arterial puncture) for tunnelled catheter placements was 3.8% and for temporary catheter placements was 1.6%; no major complications were documented. CONCLUSION: Our results lend further evidence to the claim that the success and immediate complication rates of radiologically placed central venous catheters compare favourably with blind placement and surgical placement of central venous catheters.     

Intra-biliary contrast-enhanced ultrasound for evaluating biliary obstruction during percutaneous transhepatic biliary drainage: A preliminary study

Objectives

The aimed of this study was to investigate the value of intra-biliary contrast-enhanced ultrasound (IB-CEUS) for evaluating biliary obstruction during percutaneous transhepatic biliary drainage (PTBD).

Materials and methods

80 patients with obstructive jaundice who underwent IB-CEUS during PTBD were enrolled. The diluted ultrasound contrast agent was injected via the drainage catheter to perform IB-CEUS. Both conventional ultrasound and IB-CEUS were used to detect the tips of the drainage catheters and to compare the detection rates of the tips. The obstructive level and degree of biliary tract were evaluated by IB-CEUS. Fluoroscopic cholangiography (FC) and computer tomography cholangiography (CTC) were taken as standard reference for comparison.

Results

Conventional ultrasound displayed only 43 tips (43/80, 53.8%) of the drainage catheters within the bile ducts while IB-CEUS identified all 80 tips (80/80, 100%) of the drainage catheters including 4 of them out of the bile duct (P < 0.001). IB-CEUS made correct diagnosis in 44 patients with intrahepatic and 36 patients with extrahepatic biliary obstructions. IB-CEUS accurately demonstrated complete obstruction in 56 patients and incomplete obstruction in 21 patients. There were 3 patients with incomplete obstruction misdiagnosed to be complete obstruction by IB-CEUS. The diagnostic accuracy of biliary obstruction degree was 96.3% (77/80).

Conclusion

IB-CEUS could improve the visualization of the drainage catheters and evaluate the biliary obstructive level and degree during PTBD. IB-CEUS may be the potential substitute to FC in the PTBD procedure.     

Catheter direct thrombolysis: Role of actilyse in treatment of acute deep venous thrombosis

Purpose

To evaluate the short and long term efficiency of catheter directed thrombolysis using recombinant tissue type plasminogin activator (r-TPA; Actilyse), in treating acute deep venous thrombosis of the lower limb.

Material and methods

Twenty-eight patients with acute lower limb deep venous thrombosis underwent treatment by direct intra clot injection of thrombolytic therapy; Actilyse.

Result

Thrombus lysis was completed in 23 (82.2%) of 28 patients, partial in 4 (14.3%) patients and not achieved in one (3.5%) patient. There was no major complication. There was no rethrombosis or post thrombotic syndrome in any of the treated 23 patients over the follow up period of one year.

Conclusion

The treatment of acute lower limb deep venous thrombosis using recombinant tissue type plasminogin activator (r-TPA; Actilyse), is safe, effective and achieves significantly better short and long term clinical outcome for patients.     

An Endovascular Approach to the Entrapped Central Venous Catheter After Cardiac Surgery

Purpose

Entrapment of central venous catheters (CVC) at the superior vena cava (SVC) cardiopulmonary bypass cannulation site by closing purse-string sutures is a rare complication of cardiac surgery. Historically, resternotomy has been required for suture release. An endovascular catheter release approach was developed.

Materials and Methods

Four cases of CVC tethering against the SVC wall and associated resistance to removal, suggestive of entrapment, were encountered. In each case, catheter removal was achieved using a reverse catheter fluoroscopically guided over the suture fixation point between catheter and SVC wall, followed by the placement of a guidewire through the catheter. The guidewire was snared and externalized to create a through-and-through access with the apex of the loop around the suture. A snare placed from the femoral venous access provided concurrent downward traction on the distal CVC during suture release maneuvers.

Results

In the initial attempt, gentle traction freed the CVC, which fractured and was removed in two sections. In the subsequent three cases, traction alone did not release the CVC. Therefore, a cutting balloon was introduced over the guidewire and inflated. Gentle back-and-forth motion of the cutting balloon atherotomes successfully incised the suture in all three attempts. No significant postprocedural complications were encountered. During all cases, a cardiovascular surgeon was present in the interventional suite and prepared for emergent resternotomy, if necessary.

Conclusion

An endovascular algorithm to the “entrapped CVC” is proposed, which likely reduces risks posed by resternotomy to cardiac surgery patients in the post-operative period.

     

The Value of Preprocedure Computed Tomography for Planning Insertion of Inferior Vena Cava Filters

Purpose

To determine if valuable information could be obtained from abdominal computed tomography (CT) performed before insertion of an inferior vena cava (IVC) filter.

Materials and Methods

A retrospective review was performed on IVC filter insertions with a CT performed before the procedure. Cavagram and CT were compared for renal vein and IVC anatomy, the diameter of the IVC, and the prevalence of iliocaval thrombus. Correlations were assessed among 3 reference standards for measuring the IVC at cavography.

Results

The mean IVC diameter was 23.0 mm on CT. On cavagram the mean IVC diameter was assessed by using 3 reference standards: 20.7 mm, with the catheter tip as a reference; 26.9 mm, with a radiopaque ruler; and 23.4 mm, by using a lumbar vertebral body. There was good correlation among the 3 measures of IVC diameter (Pearson's r = 0.75, P < .0001) but moderate correlation with CT (r = 0.36–0.56, P < .001). The sensitivity of cavagram for detecting retroaortic and circumaortic renal veins was 40% and 0%, respectively. Nineteen accessory renal veins (12.8%) were not seen by cavagram. Thirteen patients (8.8%) had iliocaval thrombus on cavagram, of which 12 (92.3%) were not previously detected by CT.

Conclusions

CT is more sensitive than cavagram for detection of renal vein variants and the level of the lowest renal vein. Therefore, if available, the CT should be reviewed before placement of an IVC filter to optimize positioning. Cavagram remains the criterion standard for detection of iliocaval thrombosis and is necessary before IVC filter insertion.     

Non invasive cardiac vein mapping: Role of multislice CT coronary angiography

Purpose

Coronary venous anatomy is of primary importance when implanting a cardiac resynchronization therapy device, besides, the coronary sinus can be differently enlarged depending on chronic heart failure. The aim of this study is to evaluate the usefulness of Coronary CTA in describing the coronary venous tree and in particular the coronary sinus and detecting main venous system variants.

Materials and methods

301 consecutive patients (196 ♂, mean age 63.74 years) studied for coronary artery disease with 64 slice Coronary CTA were retrospectively examined. The acquisition protocol was the standard acquisition one used for coronary artery evaluation but the cardiac venous system were visualized. The cardiac venous system was depicted using 3D, MPR, cMPR and MIP post-processing reconstructions on an off-line workstation. For each patient image quality, presence and caliber of the coronary sinus (CS), great cardiac vein (GCV), middle vein (MV), anterior interventricular vein (AIV), lateral cardiac vein (LCV), posterior cardiac vein (PCV), small cardiac vein (SCV) and presence of variant of the normal anatomy were examined and recorded.

Results

CS, GCV, MV and AIV were visualized in 100% of the cases. The LCV was visualized in 255/301 (84%) patients, the PCV in 248/301 (83%) patients and the SCV in 69/301 (23%) patients. Mean diameter of the CS was 8.7 mm in 276/301 (91.7%) patients without chronic heart failure and 9.93 mm in 25/301 (8.3%) patients with chronic heart failure.

Conclusions

Coronary CTA allows non invasive mapping of the cardiac venous system and may represent a useful presurgical tool for biventricular pacemaker devices implantation.     

Role of 320-slice multislice computed tomography coronary angiography in the assessment of coronary artery stenosis

Objective

To evaluate the effectiveness of the multislice CT coronary angiography, as a non-invasive imaging tool in assessment of coronary artery stenosis.

Patients and methods

The study included 50 patients who were referred for MSCT coronary angiography followed by catheter coronary angiography. Patients with previous coronary bypass grafts and those with coronary stents were excluded. History of contrast allergy, renal impairment and severe chest conditions were exclusion criteria. The coronary angiographic CT studies were performed using a 320 CT scanner. The catheter coronary angiographic studies were performed via femoral arterial puncture. The results of CT angiography were compared with the gold standard catheter angiography.

Results

The positive predictive value and negative predictive value of MSCT coronary angiography in detection of coronary artery stenosis were 94% and 100%, respectively.

Conclusion

In conclusion, MSCT coronary angiography is a very helpful and rapid non-invasive coronary imaging modality that was able to detect and grade coronary artery stenosis better than other noninvasive examinations used to detect CAD, such as exercise stress testing. Due to its very high negative predictive value, it may eliminate the need for invasive coronary procedures in the presence of normal coronary imaging.