Transjugular Intrahepatic Portosystemic Shunt (TIPS) - What Radiologists Should Know

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1 Transjugular Intrahepatic Portosystemic Shunt (TIPS) - What Radiologists Should Know Award: Certificate of Merit Poster No.: C-1508 Congress: ECR 2016 Type: Educational Exhibit Authors: E. Nagaya, F. T. Jojima, B. S. Nunes, O. C. Saito, G. G. Cerri, M. C. Chammas, S. M. Tochetto; Sao Paulo/BR Keywords: Prostheses, Image verification, Embolism / Thrombosis, Stents, Complications, Ultrasound-Colour Doppler, Ultrasound, Liver, Abdomen DOI: /ecr2016/C-1508 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 26

2 Learning objectives The purpose of this educational exhibit is to: Review the imaging evaluation in the pre- and post-operative of TIPS; Discuss the imaging criteria for diagnosis of device dysfunction; Show examples of earlier and later complications of TIPS. Images for this section: Page 2 of 26

3 Fig. 1: Transjugular Intrahepatic Portosystemic Shunt - device that creates a shunt between portal circulation and the systemic circulation (Modified from McNaughton et al. RadioGraphics, 2011, 31: ). modified from McNaughton DA et al. Radiographics, 2011, 31: ). Page 3 of 26

4 Background TIPS is a percutaneous interventional procedure that creates an intrahepatic shunt between portal and systemic circulation (Fig 1). It is an established procedure, with proven benefit in the treatment of portal hypertension complications, such as refractory ascites and recurrent variceal bleeding, but it is not a replacement for endoscopic therapy or surgery. Fig. 1: Transjugular Intrahepatic Portosystemic Shunt - device that creates a shunt between portal circulation and the systemic circulation (Modified from McNaughton et al. RadioGraphics, 2011, 31: ). References: modified from McNaughton DA et al. Radiographics, 2011, 31: ). Page 4 of 26

5 The main indications for TIPS are: Treatment for portal hypertension - bridge to liver transplantation Severe portal hypertension with refractory bleeding of varicose veins that cannot be successfully controlled with medical treatment, including sclerotherapy Portal hypertension with severe refractory ascites Hepatorenal syndrome Hepatopulmonary syndrome Occlusion of the hepatic veins (Budd -Chiari syndrome) Despite its benefits, the major disadvantages of the TIPS procedure are hepatic function deterioration and several procedure related complications (e.g. stenosis and occlusion) that can ultimately, lead to device dysfunction. Signs and symptoms of device malfunction are usually equivocal or absent, therefore imaging studies, mainly Colour Doppler ultrasound, have crucial role in the diagnosis of TIPS complications. Findings and procedure details TECHNICAL ASPECTS OF TIPS CREATION Most patients undergo TIPS placement with intravenous short-acting sedation using benzodiazepines and opiates. Some institutions prefer general anesthesia during TIPS procedures because of the prolonged nature of the procedure and the degree of discomfort that many patients experience during the transvenous punctures. In most TIPS the right jugular vein is accessed with ultrasonographic guidance and a catheter is placed, most commonly, into the right hepatic vein with fluoroscopy guidance. If the right hepatic vein is unsuitable for any reason any hepatic vein or even the inferior vena cava can be used. After accessing the hepatic vein a venography is performed with carbon dioxide gas (CO2) to demonstrate the location of the main portal vein, as well as the left and right branches. If it fails to fill the portal vein, an occlusion balloon catheter may be used. Then, a needle is advanced through the wall of the right hepatic vein and directed in an anteroinferior direction to access the right portal vein using the wedged hepatic venogram images as a guide. It is gently aspirated as it is withdrawn across the parenchymal tract. Page 5 of 26

6 Once portal venous blood is freely aspirated, contrast material is injected through the needle to verify the point of entry into the vessel. At this point, pressure measurements are obtained in the portal vein as well as in the right atrium (portosystemic gradient). If the portosystemic pressure gradient is significantly elevated (>12 mm Hg), the TIPS is placed. If the gradient is not elevated, the presence of a competitive shunt, such as a spontaneous splenorenal shunt, must be evaluated. The spontaneous shunts can be used to lower the portosystemic gradient, but they are not true vessels and lack normal vascular integrity, which poses a risk for rupture. The intrahepatic parenchymal tract is dilated with a balloon and a self-expanding metallic stent is then placed across the tract and dilated to the desired diameter by using an angioplastic balloon (Fig 2). Page 6 of 26

7 Fig. 2: Resumed step-by-step of the TIPS procedure. References: - Sao Paulo/BR Once stents are deployed, portal venography and pressure measurements in the portal vein and the right atrium are repeated. To prevent a rebleeding episode in patients with history of variceal bleeding, the portosystemic gradient should be below 12 mmhg. If this gradient is below 5 mmhg it has been reported increased risk of liver failure and severe hepatic encephalopathy and an intervention is required. A color Doppler ultrasound is obtained 24 hours after the procedure to show shunt patency. It is usually repeated one week later if it is an uncovered stent or one month later if it is covered. After that, if there are no complications, the ultrasound is repeated 3 months later and then every 6 months until the clinical outcome. IMAGING EVALUATION The superiority of computerized tomography (CT) or magnetic resonance imaging (MRI) over the ultrasound is controversial. Thus, ultrasound is the primary tool to evaluate TIPS. Computerized Tomography and Magnetic Resonance Imaging are directed to those cases in which the evaluation by the ultrasound is restrict or technically compromised. This surveillance is especially important in suspected occlusion of TIPS. The assessment should include the grayscale, color Doppler, and spectral Doppler analysis. Pre-TIPS assessment: - Liver morphology, hepatic masses. - Anatomic variations, such as extra-hepatic portal vein bifurcation. - Presence and volume of ascites. - Diameter of the inferior vena cava and portal vein. - Patency and flow direction of portal vein and its main branches, splenic vein, and superior mesenteric vein. The portal vein flow velocity is also important to be evaluated. - Patency and flow direction of the 3 major hepatic veins. Page 7 of 26

8 - Evaluation of the collaterals vessels hemodynamic. Post-TIPS assessment: Besides the same aspects we should evaluate in pre-tips assessment, now we will have to evaluate: - Stent configuration / position. - Patency and flow direction in portal vein and branches, velocity of the mid portal vein (not near to the shunt). - Patency, flow direction, and velocity of the splenic vein and superior mesenteric vein. - Peak velocity and waveforms in the proximal, mid, and distal segments of the device. In a follow-up study, the comparison with previous results is mandatory. - Patency and flow direction in hepatic veins (especially the segment between the device and the inferior vena cava, of which we should determine the velocity). - Evaluation of the hemodynamic evolution of collateral vessels (paraumbilical, left gastric, splenorenal shunt). - Presence of stenosis: if so, it is necessary to document the peak velocity, usually at the point of maximum turbulence. After the implantation of TIPS, some hemodynamic parameters adaptations are expected, as shown below (see also Fig 3): - Velocity in the shunt device should be greater than 50 cm/s, ideally between 90 to 150 cm/s, but acceptable from 50 to 200~250 cm/s. - Velocity of portal vein should be greater than 30 cm/s. Note that it should increase significantly after TIPS (more than 50% of increase). - The direction of portal vein should be hepatopetal. - The direction of main intrahepatic portal vein branches should be retrograde or stagnant. - Reduction in the caliper of the collaterals vessels. If the flow in splenic vein is hepatofugal before the TIPS it should be hepatopetal post-tips in a normal funcionating device. Page 8 of 26

9 Fig. 3: Normally functioning TIPS. Gray-scale US images showed a stent connecting the right branch of the portal vein (a) with the right hepatic vein (b). Color Doppler US image (c) showed an anterograde direction of the flow - from portal vein to hepatic vein. Spectral Doppler US images demonstrated: (d) portal vein velocity of 41.7 cm/s (>30 cm/s) and a low resistance and slightly whirl flow, with normal and constant velocity within the proximal (115 cm/), mid (150 cm/s) and distal (125 cm/s) segments of the shunt device (e, f and g). References: Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil DEVICE DYSFUNCTION Stenosis Stenosis might occur at the site of portal anastomosis (Fig 4), at the draining hepatic vein anastomosis (Fig 5 and 6), due device fold or due device reduced lumen (in-stent stenosis or stent retraction) (Fig 7). Page 9 of 26

10 A hemodynamically significant shunt stenosis is defined as a reduction of more than 50% in the diameter of the stent or a portal pressure gradient of more than mmhg. There still is no consensus of the ultrasonographic criteria to determine a device dysfunction. Diverse velocities thresholds have been described in different studies. A combination of Doppler velocimetric parameters seems to be the most helpful approach to detect shunt failure. The main ultrasonographic signs of device dysfunction include: - Velocity in the device under 50 cm/s (sensitivity nearly 100% and specificity 93%). - Velocity in the device under 60 cm/s, with decrease comparing to previous assessments. - A decrease by more than 50% in the shunt velocity over time. - Focal increases on device velocity. - Difference between two points in the device over 100 cm/s. - Velocity in portal vein under 30 cm/s. - Flow direction reversion in hepatic veins. - Flow direction reversion in portal branches (from hepatofugal to hepatopetal). - Flow direction reversion in collateral vessels comparing to previous assessments. Page 10 of 26

11 Fig. 4: TIPS malfunctioning - stenosis in the portal anastomosis. Perceptible narrowing was seen in the gray-scale US image (a) and was also apparent in the Color (b) and Power (c) Doppler images (arrows). Spectral Doppler images showed highly elevated velocity (240.8 cm/s) in the segment after the narrowing point comparing with the segment proximal the narrowing point (63.5 cm/s). References: Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Page 11 of 26

12 Fig. 5: Fig 5: TIPS malfunctioning - stenosis at the draining hepatic vein. Spectral Doppler US images demonstrated: (a) portal vein velocity of 29 cm/s (nl > 30 cm/s) and velocity within the (b) proximal (83 cm/s), (c) mid (59 cm/s) and (d) distal (223 cm/s) segments of the shunt device, suggesting a stenosis at the hepatic vein anastomosis. The TIPS revision was performed by placing a stent at the stenosis point (e and f). Post-interventional procedure angiography show a patent device and absence of residual stenosis. Page 12 of 26

13 References: Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Fig. 6: US examination performed after the TIPS revision (Fig 5 - stenosis of the draining hepatic vein) showed a normally functionanting device: (a) portal vein velocity of 40 cm/s (> 30 cm/s), velocity within the (b) proximal (235 cm/s), (c) mid (224 cm/s) and (d) distal (195 cm/s) segments of the shunt device. No residual stenosis in the site of hepatic vein was identified. References: Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Page 13 of 26

14 Fig. 7: TIPS malfunctioning - stenosis due to reduced lumen of the device. (a and b) US images at left upper quadrant of the abdomen show a persistent splenorenal shunt. Perceptible narrowing of the entire device lumen was seen in the color Doppler US image. Spectral Doppler images demonstrate: (c) portal vein velocity of 44 cm/s (>30 cm/s) and lower velocities within the (d) proximal (65 cm/s), (e) mid (33 cm/s) and (j) distal (21 cm/s) segments of the shunt device. References: Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Other vascular complications, e.g., inferior vena cava thrombosis might also interfere in the device function (Fig 8 and 9). Page 14 of 26

15 Fig. 8: Inferior Vena Cava Thrombosis - The patient was refereed to US evaluation because a TIPS dysfunction was suspected due to persistent ascites (a) US evaluation showed a normally functioning TIPS. Notice the reversion in the left branch of portal vein flow (b). Spectral Doppler images demonstrate normal portal vein velocity (c) and a low resistance and slightly whirl flow, with normal and constant velocity within the proximal, mid and distal segments of the shunt device (d, e and f). A careful examination showed that the cause of refractory ascites was a extensive clot in the intrahepatic segment of the inferior vena cava (see Fig 9). References: Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Page 15 of 26

16 Fig. 9: Inferior Vena Cava Thrombosis - Gray-scale (a and b) and color Doppler (c and d) US images showed a extensive clot in the intrahepatic segment of the inferior vena cava causing the device malfunctioning showed in Fig 8. References: Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Occlusion No flow signs on US Doppler study (Fig 10). The thrombosis of the shunt device might be due to earlier complication of device creation (stent kinking or stent retraction) or as a result of late complication (progressive in-stent stenosis or tumor invasion). Page 16 of 26

17 Fig. 10: TIPS oclusion - No flow sign at colour and power Doppler US evaluation. References: Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Images for this section: Page 17 of 26

18 Fig. 1: Transjugular Intrahepatic Portosystemic Shunt - device that creates a shunt between portal circulation and the systemic circulation (Modified from McNaughton et al. RadioGraphics, 2011, 31: ). modified from McNaughton DA et al. Radiographics, 2011, 31: ). Fig. 2: Resumed step-by-step of the TIPS procedure. - Sao Paulo/BR Page 18 of 26

19 Fig. 3: Normally functioning TIPS. Gray-scale US images showed a stent connecting the right branch of the portal vein (a) with the right hepatic vein (b). Color Doppler US image (c) showed an anterograde direction of the flow - from portal vein to hepatic vein. Spectral Doppler US images demonstrated: (d) portal vein velocity of 41.7 cm/s (>30 cm/ s) and a low resistance and slightly whirl flow, with normal and constant velocity within the proximal (115 cm/), mid (150 cm/s) and distal (125 cm/s) segments of the shunt device (e, f and g). Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Page 19 of 26

20 Fig. 4: TIPS malfunctioning - stenosis in the portal anastomosis. Perceptible narrowing was seen in the gray-scale US image (a) and was also apparent in the Color (b) and Power (c) Doppler images (arrows). Spectral Doppler images showed highly elevated velocity (240.8 cm/s) in the segment after the narrowing point comparing with the segment proximal the narrowing point (63.5 cm/s). Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Page 20 of 26

21 Fig. 6: US examination performed after the TIPS revision (Fig 5 - stenosis of the draining hepatic vein) showed a normally functionanting device: (a) portal vein velocity of 40 cm/s (> 30 cm/s), velocity within the (b) proximal (235 cm/s), (c) mid (224 cm/s) and (d) distal (195 cm/s) segments of the shunt device. No residual stenosis in the site of hepatic vein was identified. Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Page 21 of 26

22 Fig. 7: TIPS malfunctioning - stenosis due to reduced lumen of the device. (a and b) US images at left upper quadrant of the abdomen show a persistent splenorenal shunt. Perceptible narrowing of the entire device lumen was seen in the color Doppler US image. Spectral Doppler images demonstrate: (c) portal vein velocity of 44 cm/s (>30 cm/s) and lower velocities within the (d) proximal (65 cm/s), (e) mid (33 cm/s) and (j) distal (21 cm/ s) segments of the shunt device. Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Page 22 of 26

23 Fig. 8: Inferior Vena Cava Thrombosis - The patient was refereed to US evaluation because a TIPS dysfunction was suspected due to persistent ascites (a) US evaluation showed a normally functioning TIPS. Notice the reversion in the left branch of portal vein flow (b). Spectral Doppler images demonstrate normal portal vein velocity (c) and a low resistance and slightly whirl flow, with normal and constant velocity within the proximal, mid and distal segments of the shunt device (d, e and f). A careful examination showed that the cause of refractory ascites was a extensive clot in the intrahepatic segment of the inferior vena cava (see Fig 9). Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Page 23 of 26

24 Fig. 9: Inferior Vena Cava Thrombosis - Gray-scale (a and b) and color Doppler (c and d) US images showed a extensive clot in the intrahepatic segment of the inferior vena cava causing the device malfunctioning showed in Fig 8. Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Fig. 10: TIPS oclusion - No flow sign at colour and power Doppler US evaluation. Department of Radiology, Clinics Hospital, University of São Paulo, SP, Brazil Page 24 of 26

25 Conclusion Follow up imaging studies, particularly US, after TIPS can provide nonivasive assessment of device patency and complications. Personal information References Arun J. Sanyal, Arthur M. Freedman, Velimir A. Luketic, Preston P. Purdum Iii, Mitchell L. Shiffman, John Demeo, Pat E. Cole, and Jaime Tisnado. The Natural History of Portal Hypertension After Transjugular Intrahepatic Portosystemic Shunts. Gastroenterology (1997); 112(3): Baik SK. Haemodynamic evaluation by Doppler ultrasonography in patients with portal hypertension: a review. Liver Int. (2010); 30(10): Carmen Gallego, MD, Maria Velasco, MD, Pilar Marcuello, MD, Daniel Tejedor, MD, Lourdes De Campo, MD, and Alfonsa Friera, MD, Congenital and Acquired Anomalies of the Portal Venous System. Radiographics (2011); 22: Darcy M. Evaluation and Management of Transjugular Intrahepatic Portosystemic Shunts. American Journal of Roetgenology (2012); 199: Kalva SP, MD, Salazar GM, MD, Walker TG, MD. Transjugular Intrahepatic Portosystemic SHunt for Acute Variceal Haemorrhage. Techniques in Vascular and Interventional Radiology (2009); 19(37): Kiyosuke H, MD, Ibukuro K, MD, Maruno M, MD, Tanoue S, MD, Hongo N, Mori H, MD. Multidetector CT ANatomy of Drainage Routes of Gastric Varices: A pictorial Review. RadioGraphics (2013); 33: McNaughton DA, MD, Abu-Yousef MM, MD. Doppler US of the Liver Made Simple. RadioGraphics (2011); 31: Robinson KA, MD, Middleton WD, MD, AL-Sukaiti R, MD, Teefey SA, MD, Dahiya N, MD. Doppler Sonography of Portal Hypertension. Ultrasound Quarterly (2009); 25:3-13. Seeger M, Günther R, Hinrichsen H, Both M, Helwig U, Arlt A, Stelck B, Bräsen JH, Sipos B, Schafmayer C, Braun F, Bröring DC, Schreiber S, Hampe J. Chronic portal vein thrombosis: transcapsular hepatic collateral vessels and communicating ectopic varices. Radiology (2010); 257(2): Page 25 of 26

26 Scheinfeld MH, Bilali A, Koenigsberg M. Understanding the Spectral Doppler Waveform of the Hepatic Veins in Health and Disease. Radiographics (2009); 29: Tirumani SH, MD, Shanbhogue AKP, MD, Vikram R, MBBS, MRCP, FRCR, Prasad SR, MD, Menias CO, MD. Imaging od the Porta Hepatis: SPectrum of Disease. RadioGraphics (2014); 34: Zizka J, Elias P, Krajina A, Michl A, Lojik M, Ryska P, MAskova, J, Hulek P, Safka V, Vanasek T, Bukac J. Value of Doppler Sonography in Revealing Transjugular Intrahepatic Prtosystemic Shunt Malfunction: A 5-Year Experience in 216 Patients. American Journal of Roetgenology (2000); 175(1): Page 26 of 26