Ultrasound assessment of coronary veins as non-invasive marker for esophageal varices

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1 Ultrasound assessment of coronary veins as non-invasive marker for esophageal varices Poster No.: C-1657 Congress: ECR 2011 Type: Scientific Exhibit Authors: R. Castellón Siles, A. Thomas, X. Serres, O. Persiva Morenza; Barcelona/ES Keywords: Abdomen,, Ultrasound, Diagnostic procedure, Liver DOI: /ecr2011/C-1657 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 Purpose Background Esophageal varices are found in up to 50% of cirrhotic patients reported as high as 30% in patients with variceal bleeding (1) with a mortality rate (2) (3) (1). Screening endoscopy is recommended by both American and European consensus guidelines in patients with established cirrhosis and proved cost-effective in decompensated cirrhosis though the universal use of screening endoscopy in these (4) patients is not so clear to be cost effective. So it is important to find a way to identify those patients who can benefit from prophylactic and endoscopic therapies and avoid unnecessary endoscopies. A noninvasive diagnostic tool for diagnosing esophageal varices before invasive screening endoscopy would be immensely helpful in this group of patients. Abdominal ultrasound has played an important role in the management of patients with chronic hepatopathy. Classically, the ultrasound evaluation of these patients included portal vein diameter, velocity at the portal vein and, specially, spleen size as predictors of portal (5) hypertension with good results for the prediction of recurrent bleeding, but the ability to predict the existence of esophageal varices is limited when these classical ultrasound parameters are considered even when Doppler studies are performed determinations as the platelet count are included (7) (6) or laboratory. Purpose of the study The purpose of this study is to compare the ability to correctly classify the patients with varices of the traditional imaging approach of patients with portal hypertension (spleen size, portal vein diameter and portal vein speed) with the suggested approach including sonographic evaluation of the coronary veins. In order to clarify the results the sonographic appearance and assessment of the coronary veins are first reviewed as long as the ultrasound evaluation of these vascular structures has been only rarely described (8) and not routinely used in clinical practice. Page 2 of 26

3 Methods and Materials Sonographic assessment of the coronary veins A note on anatomy The anatomy of the venous system is known to be extensively variable throughout the body and the gastric veins are no exception. A coronary vein may join the portal system at three different points: the splenoportal confluence (59%), the portal vein (24%) or the splenic vein (17%) as reported in a large (9) autopsy study. (Fig. 1) Even though this autopsy studied failed to demonstrate the coexistence of more than one coronary vein at the same time, venography studies in cirrhotic patients have reported the presence of multiple coronary veins joining the portal system in one of the locations previously described (10) And what about ultrasound? To our knowledge, Wachsberg and Simmons were the first to describe the sonographic appearance of this vascular structures and its potential implication as predictors of (8) esophageal bleeding in patients with portal hypertension evaluation of the gastric vein had already been described though the ultrasound (11). Ultrasound may nicely depict not only the presence but also the size and flow direction within the vessel once the region anatomy and the sonographic appearance of the coronary veins are mastered. The paper from Wachsberg did not report any patient with (12) multiple coronary veins but in our present and also in past studies we have seen the coexistence of up to three different coronary veins in the same patient, an observation consistent with the venography study by Lafortune (10) and connecting with the portal system at the points reported in an autopsy study by Douglass (9). Despite these veins have been considered before as a single structure with a high anatomical variability regarding its origin and course it is very important to stress that this assumed variability is not so and that these venous structures can coexist at the same time in a single patient. How do I get there with my transducer? The coronary veins are best seen when a longitudinal subxiphoideal approach is used with a variable degree of obliquity along the inferior border of the right ribs (Fig. 2). Page 3 of 26

4 The anatomy of the hepatic hilum is complex and the relationship between the gastric veins and the celiac trunk is important for its correct identification. Regarding the location the coronary vein joins the portal system and the anatomic relationship with the arterial structures of the celiac trunk three gastric veins are described: Gastric Vein 1: Joins the portal system at the portal vein and lies posterior to the hepatic artery being the closest to the hepatic hilum Fig. 0 on page Gastric Vein 2: Joins the portal system at the splenoportal confluence and lies anterior to the bifurcation of the hepatic and splenic arteries Fig. 0 on page Gastric Vein 3: Joins the portal system at the splenic vein and lies posterior to the splenic artery being the most distant to the hepatic hilum Fig. 0 on page It is important to remember that not only these gastric veins may be found in combination in one patient, they also have a very distinctive and definite course with constant relations with the surrounding anatomic structures. Fig. 0 on page Window problems The identification of the gastric veins may be sometimes challenging due to its small size and the anatomic complexity of this area. The existence of excessive gas or fat or a shrunk left hepatic lobe in cirrhotic patients may also difficult the access to this area. Specially challenging is the cirrhotic patient with a small and heterogenous parenchyma that attenuates even further the ultrasound beam. Despite these limitations, the coronary veins and the whole hepatic hilum area has been accessible in roughly a 90% of 951 patients, a value similar to previously reported studies. Summary The next diagram shows the location of the three gastric veins and the relationships with surrounding structures. Page 4 of 26

5 Fig.: HA: Hepatic Artery. SA: Splenic Artery. PV: Portal Vein. Ch: Choledoch References: Radiology, Vall d'hebron - Barcelona/ES Study population 951 consecutive patients are prospectively studied with US. Only those patients who underwent upper gastrointestinal endoscopy with available measurements of spleen size, portal vein diameter, portal vein flow velocity and gastric veins presence, size and flow direction evaluation are considered, leaving 142 patients for this study. The population characteristics are summarized in the next table. Page 5 of 26

6 Fig. References: Radiology, Vall d'hebron - Barcelona/ES Variables considered Sonographic Spleen size Measured in centimeters at the maximal cross-sectional image. Only one measurement is considered. The cutoff value is established at 13 cm. (Fig. 3 at the sidebar) Portal vein diameter Page 6 of 26

7 The diameter of the extrahepatic portal vein is considered in milimeters through an anterior subcostal approach and obtaining an image along its long axis. A diameter of 13 mm or less is considered normal. (Fig. 4 at the sidebar) Portal vein flow velocity The presence of flow and velocity were assessed through a right lateral intercostal window in order to reduce as much as possible the angle between the vessel axis and the ultrasound beam, rendering a more reliable measurement. A flow velocity below the cutoff value of 18 cm/sec is considered abnormal. (Fig. 5 and 6 at the sidebar) Gastric veins The assessment of the gastric veins was performed as previously described in every patient considering the presence and type of gastric vein, the diameter of the vessel at the segment closest to the portal system and the direction of the blood flow (hepatopetal or reversal). Fig. 0 on page Endoscopic Upper gastrointestinal endoscopy is performed in all patients to determine exclusively the presence of esophageal varices regardless its grade. Statistical analysis A descriptive analysis of the patient's characteristics is performed regarding the presence or absence of esophageal varices in 142 patients with available data of spleen size, portal vein diameter, portal vein flux velocity and presence and size of gastric veins. For qualitative variables frequencies and percentages are calculated for each group and compared using a chi-square test. For quantitative variables median and interquartilic range are obtained and compared using Kruskal-Wallis test. A logistic regression model was adjusted to evaluate the variables associated to the presence or absence of esophageal varices and with the model obtained the ROC curve and the area under curve were calculated using a probability of.5 as cutoff for the logistic equation. Page 7 of 26

8 Images for this section: Fig. 0: Schematic representation of the aorta, hepatic artery and splenic artery (in red) and the splenoportal venous system with the superior and inferior mesenteric veins (in blue). The gastric vein may join the portal system at the portal vein (left), at the splenic vein (right) or in a middle position between the origin of the hepatic and splenic arteries (center) Radiology, Vall d'hebron - Barcelona/ES Page 8 of 26

9 Fig. 0: Recommended oblique longitudinal subxiphoideal approach to evaluate the gastric veins. Radiology, Vall d'hebron - Barcelona/ES Fig. 0: Spleen size measurement at the maximum cross-sectional image Radiology, Vall d'hebron - Barcelona/ES Page 9 of 26

10 Fig. 0: Portal vein diameter measurement along its long axis Radiology, Vall d'hebron - Barcelona/ES Page 10 of 26

11 Fig. 0: Portal vein blood flow patency at color Doppler Radiology, Vall d'hebron - Barcelona/ES Page 11 of 26

12 Fig. 0: Pulsed Doppler ultrasound to quantificate the blood flow velocity within portal vein Radiology, Vall d'hebron - Barcelona/ES Page 12 of 26

13 Results Results Esophageal varices were detected in 57.7% (84/142) of patients. The traditional approach yielded an area under ROC curve of with a 71.95% sensitivity, 68.33% specificity, 75.64% PPV and 64.06% NPV. The global accurancy was 70.42%. Fig.: Traditional approach as predictor for esophageal varices. References: Radiology, Vall d'hebron - Barcelona/ES Page 13 of 26

14 Fig.: Traditional approach. ROC curve and crossing between sensibility and specificity. References: Radiology, Vall d'hebron - Barcelona/ES The evaluation of the gastric veins by itself proved to be a predictor of the presence of esophageal varices but with ROC curve of yielding lower values of sensitivity (49.47%) and accuracy (67.88%) but proving highly specific (92.86%). Page 14 of 26

15 Fig.: Gastric veins evaluation as predictor for esophageal varices. References: Radiology, Vall d'hebron - Barcelona/ES Page 15 of 26

16 Fig.: Gastric veins evaluation. ROC curve and crossing between sensibility and specificity. References: Radiology, Vall d'hebron - Barcelona/ES When joining the gastric veins evaluation and the traditional approach the area under ROC curve reached with a 80.49% sensitivity, 71.67% specificity, 79.52% PPV and 72.88% NPV. The best global accuracy was obtained with a 76.76%. Page 16 of 26

17 Fig.: Traditional approach AND gastric veins evaluation as predictors for esophageal varices. References: Radiology, Vall d'hebron - Barcelona/ES Page 17 of 26

18 Fig.: Traditional approach AND gastric veins evaluation. ROC curve and crossing between sensibility and specificity. References: Radiology, Vall d'hebron - Barcelona/ES The differences between the model including gastric veins evaluation and the traditional approach were considered statistically significant (p value: 0.037) Limitations to the study Page 18 of 26

19 First, even though the US data collection was prospective, the endoscopy study was not carried out in every patient and was prescribed depending on the clinical status of the patient, so this information was retrospectively gathered. Second, the fact that the endoscopy study was prescribed on clinical basis brings in a selection bias favouring patients with a more severe hepatopathy and a higher esophageal varices development probability. Third, time lapse between ultrasound and endoscopy weakens the relation between US findings and the presence of varices as long as esophageal varices may develop in the time lapse between a normal US examination and the endoscopy. Fourth, the patient population is heterogeneous and includes patients with well-known hepatopathy, oncologic patients and patients with no established diagnosis among others. The figures regarding sensibility, especificity and diagnostic accuracy are expected to improve in selected groups of patients (ie. compensated chronic hepatopathy patients). Page 19 of 26

20 Images for this section: Fig. 0: Traditional approach as predictor for esophageal varices. Radiology, Vall d'hebron - Barcelona/ES Page 20 of 26

21 Fig. 0: Gastric veins evaluation as predictor for esophageal varices. Radiology, Vall d'hebron - Barcelona/ES Page 21 of 26

22 Fig. 0: Traditional approach AND gastric veins evaluation as predictors for esophageal varices. Radiology, Vall d'hebron - Barcelona/ES Page 22 of 26

23 Conclusion The inclusion of the coronary veins evaluation in the assessment of patients with hepatic disease increases the diagnostic accuracy for the presence of esophageal varices when compared with a more traditional approach including portal vein evaluation and spleen size. The existence of any gastric vein with a diameter bigger than 6 mm or with reversal flow is a highly specific predictor of esophageal varices. Therefore, accurate investigation of the location, size and flow direction of the gastric veins is recommended and should be performed routinely in any patient with hepatic disease. Page 23 of 26

24 References 1. Luketic VA, Sanyal AJ. Esophageal varices. I. Clinical presentation, medical therapy, and endoscopic therapy. Gastroenterol. Clin. North Am Jun;29(2): Grace ND. Diagnosis and treatment of gastrointestinal bleeding secondary to portal hypertension. American College of Gastroenterology Practice Parameters Committee. Am. J. Gastroenterol Jul;92(7): de Franchis R. Updating consensus in portal hypertension: report of the Baveno III Consensus Workshop on definitions, methodology and therapeutic strategies in portal hypertension. J. Hepatol Nov;33(5): Spiegel BMR, Targownik L, Dulai GS, Karsan HA, Gralnek IM. Endoscopic screening for esophageal varices in cirrhosis: Is it ever cost effective? Hepatology Feb;37(2): Schmassmann A, Zuber M, Livers M, Jäger K, Jenzer HR, Fehr HF. Recurrent bleeding after variceal hemorrhage: predictive value of portal venous duplex sonography. AJR Am J Roentgenol Ene;160(1): Schepis F. Which patients with cirrhosis should undergo endoscopic screening for esophageal varices detection? Hepatology ;33(2): Barrera F, Riquelme A, Soza A, Contreras A, Barrios G, Padilla O, et al. Platelet count/spleen diameter ratio for non-invasive prediction of high risk esophageal varices in cirrhotic patients. Ann Hepatol Dic;8(4): Wachsberg RH, Simmons MZ. Coronary vein diameter and flow direction in patients with portal hypertension: evaluation with duplex sonography and correlation with variceal bleeding. AJR Am J Roentgenol Mar;162(3): Douglass BE, Bagenstoss AH, Hollinshead WH. The anatomy of the portal vein and its tributaries. Surg Gynecol Obstet Nov;91(5): Lafortune M, Marleau D, Breton G, Viallet A, Lavoie P, Huet PM. Portal venous system measurements in portal hypertension. Radiology Abr;151(1): Page 24 of 26

25 11. Patriquin H, Lafortune M, Burns PN, Dauzat M. Duplex Doppler examination in portal hypertension: technique and anatomy. AJR Am J Roentgenol Jul;149(1): Persiva O, Serres X, Sarrias M, Roche S, Vilà C, Genescà J. Ultrasonographic evaluation of coronary veins as an esophageal varices predictor. ECR Poster number C-414. Page 25 of 26

26 Personal Information Page 26 of 26