Background and Study Aims: The azygos vein plays an important role as a drainage system for the superior portosystemic collateral circulation in portal hypertensive patients. Endoscopic ultrasonography (EUS) and Doppler EUS allow the performance of hemodynamic studies of the azygos vein. In this study, we observed the changes in the azygos vein which occur with variceal obliteration by endoscopic injection sclerotherapy (EIS).
Patients and Methods: We recruited patients with portal hypertension and bleeding varices who were not on portal pressure-lowering agents and who were scheduled for the EIS program. EUS was performed in these patients to study the azygos vein at the start of EIS. The azygos vein diameter, maximal velocity (Vmax), and blood flow volume index (BFVI) were measured. After variceal obliteration and within 1 week, another EUS study of the azygos vein was carried out.
Results: Out of 40 patients recruited into the study variceal obliteration and EUS assessment of the azygos vein, within 1 week of obliteration, was achieved in 33 We noticed a significant increase in azygos vein diameter (P < 0.001) and BFVI (P = 0.001) following variceal obliteration. No significant change was observed in Vmax (P > 0.05). In one patient, marked caliber irregularities were observed in the azygos vein after variceal obliteration.
Conclusions: Using EUS and Doppler EUS, hemodynamic studies of the azygos vein blood flow can be performed, allowing the monitoring of the effects of EIS and variceal obliteration on the superior portosystemic collateral circulation. The clinical significance of the observed changes in azygos blood flow that occur with variceal obliteration should be investigated in further studies and correlated with short-term and long-term outcome.
References
1
Bosch J, Groszmann RJ.
Measurement of azygos venous blood flow by a continuous thermal dilution technique - an index of blood flow through gastroesophageal collaterals in cirrhosis.
Hepatology.
1984;
4
424-429
2
Calès P, Braillon A, Jiron I, Lebrec D.
Superior portosystemic collateral circulation estimated by azygos blood flow in patients with cirrhosis.
J Hepatol.
1984;
1
37-46
3
Sukigara M, Komazaki T, Ohata M, et al.
Transesophageal real-time dimensional Doppler echography - a new method for the evaluation of azygos venous flow.
Gastrointest Endosc.
1988;
34
125-128
7
Salama ZA, Kassem AM, Giovannini M, Hunter MS.
Endoscopic ultrasonographic study of the azygos vein in patients with varices.
Endoscopy.
1997;
29
748-750
8
Sukigara M, Shimoji K, Ohata M, et al.
Effects of propranolol and nitroglycerin on cephalad collateral venous flow in patients with cirrhosis: Evaluation using transoesophageal real-time two-dimensional Doppler echography.
Am J Gastroenterol.
1988;
83
1248-1254
12
Boustière C, Dumas O, Jouffre C, et al.
Endoscopic ultrasonography classification of gastric varices in patients with cirrhosis. Comparison with endoscopic findings.
J Hepatol.
1993;
19
268-272
13
Pontes JM, Leitao MC, Portek FA, et al.
Endoscopic ultrasonography in the treatment of esophageal varices by injection sclerotherapy and band ligation: do we need it?.
Eur J Gastroenterol Hepatol.
1995;
7
41-46
14
Dhiman RK, Choudhuri G, Saraswat VA, et al.
Role of paraesophageal collaterals and perforating veins on outcome of endoscopic sclerotherapy for esophageal varices: an endosonographic study.
Gut.
1996;
38
759-764
15
Leung KS, Sung JY, Ahuja AT, et al.
Large paraesophageal varices on endosonography predict recurrence of esophageal varices and rebleeding.
Gastroenterology.
1997;
122
1811-1816
19
Lee YT, Sung JJY, Yung MY, et al.
Use of color Doppler EUS in assessing azygos blood flow for patients with portal hypertension.
Gastrointest Endosc.
1999;
50
47-52
21
Sugano S, Yamamoto K, Takamura N, et al.
Azygos venous blood flow while fasting, postprandially, and after endoscopic variceal ligation, measured by magnetic resonance imaging.
J Gastroenterol.
1999;
34 (3)
310-314
22
Yokoyama M, Shijo H, Ota K, et al.
Effects of endoscopic variceal sclerotherapy on azygos vein blood flow and systemic haemodynamics.
J Gastroenterol Hepatol.
1996;
11 (8)
780-785
24
Hashizume M, Kitano S, Sugimachi K, Sueishi K.
Three dimensional view of the vascular structure of the lower esophagus in clinical portal hypertension.
Hepatology.
1988;
8
1482-1487
25
Lin CY, Lin PW, Tsai HM, et al.
Influence of paraesophageal venous collaterals on efficacy of endoscopic sclerotherapy for esophageal varices.
Hepatology.
1993;
19
602-608
