ENDOSKOPSKO LIGIRANJE VARIKSA JEDNJAKA ELASTICNIM PRSTENOVIMA I OMCAMA
Sasa Grgov
Department of Medicine, Unit of Gastroenterology, Health Centre, Leskovac
Abrevation used in this article:
EVL, endoscopic variceal ligation;
EST, endoscopic sclerotherapy
Acknowledgment: special thanks to Prim. dr sc. D. Djurdjevic for useful advise on the aplication of the variceal ligation technique.
Address correspondence to:
Prim. mr sc. Sasa Grgov
Department of Medicine,
Health Centre Leskovac,
Svetozara Markovica 116,
16000 LESKOVAC
Tel. (016) 251244 (744) 244972
Fax. (016) 247810
ABSTRACT
The prospective study included 32 patients with portal hypertension and esophageal varices which were treated by endoscopic ligation with elastic rings (n=27) and endo-loops (n=5), because of the active variceal bleeding, recent bleeding and primary prevention of bleeding. Ligation by elastic rings was done with Pauldrach’s ligation device, as described by Stiegmann. Ligation by endo-loops was done with a special device constructed by Olympus. Ligation was repeated in the intervals of 7-14 days, until the complete variceal obliteration or reduction of the variceal size to grade I was achieved. After that, endoscopic examinations were done every three months, when newly formed varices were ligated. Endoscopic ligation obtained the healing of the active variceal bleeding in all patients. Variceal eradication was achieved in 96,8% of the patients, with average 2,7 treatment sessions and 5,1 ligatures per treatment session. On the whole, 86 sessions of variceal ligation were made with 440 applied ligatures, with no serious complications observed. During the average follow-up of 15 months, 4 patients (12,5%) had recurrent varices which were eradicated in a repeated ligation. There was no recurrent haemorrhage. Three patients (9,3%) died because of the aggravation of the liver disease (n=2) and the development of the hepatocellular carcinoma (n=1). After the esophageal variceal eradication 2 patients (6.2%) went through the aggravation of the portal gastropathy and also 2 patients (6.2%) experienced gastric varices. We conclude that the endoscopic ligation is an efficient and safe method of the esophageal variceal treatment in patients with the portal hypertension. Ligation by loops has advantage over the ligation by elastic rings with Pauldrach’s ligation device because of the absence of the overtube and better visualisation of the varices.
Key words: esophageal varices, endoscopic ligation with elastic rings, endoscopic ligation with endo-loops, portal gastropathy, gastric varices.
SAZETAK
Prospektivnim ispitivanjem obuhvaceno je 32 pacijenta sa portnom hipertenzijom i variksima jednjaka, koji su leceni endoskopskim ligiranjem elasticnim prstenovima (n=27) i omcama (n=5), zbog aktivnog krvarenja iz variksa, skorasnjeg krvarenja i primarne prevencije krvarenja. Ligiranje elasticnim prstenovima je obavljeno Pauldrach-ovim ligatorom, kako je opisao Stiegmann. Ligiranje omcama je ucinjeno posebnim uredjajem koji je konstruisao Olympus. Ligiranje je ponavljano u intervalima od 7-14 dana, do potpune obliteracije variksa ili redukcije velicine variksa do I stepena. Nakon toga, endoskopski pregledi su obavljani svaka tri meseca, kada su ligirani novoformirani variksi. Endoskopskim ligiranjem postignuta je sanacija aktivnog krvarenja iz variksa kod svih pacijenata. Eradikacija variksa postignuta je u 96,8% pacijenata, sa prosecno 2,7 tretman sesije i 5,1 ligaturu po jednoj tretman sesiji. Ukupno je sprovedeno 86 sesija ligiranja variksa sa ukupno postavljenih 440 ligatura, bez zabele`enih ozbiljnih komplikacija. Tokom prosecnog pracenja od 15 meseci, kod 4 (12,5%) pacijenta je doslo do pojave rekurentnih variksa, koji su eradicirani ponovnim ligiranjem. Rekurentnog krvarenja nije bilo. Tri pacijenta (9,3%) je umrlo zbog pogorsanja bolesti jetre (n=2) i razvoja hepatocelularnog karcinoma (n=1). Posle eradikacije variksa jednjaka kod 2 (6,2%) pacijenta je doslo do pogorsanja portne gastropatije i takodje kod 2 (6,2%) pacijenta je doslo do pojave gastricnih variksa. Zakljucujemo da je endoskopsko ligiranje efikasan i bezbedan metod lecenja variksa jednjaka u pacijenata sa portnom hipertenzijom. Ligiranje omcama ima prednost nad ligiranjem elasticnim prstenovima Pauldrach-ovim ligatorom, zbog odsustva tubusa i bolje vizualizacije variksa.
Kljucne reci: variksi jednjaka, endoskopsko ligiranje elasticnim prstenovima, endoskopsko ligiranje omcama, portna gastropatija, gastricni variksi.
INTRODUCTION
Bleeding from oesophageal varices is the most serious and potentially fatal complication of portal hypertension. The rise of portal pressure over 12 mm Hg is necessary for the development of varices. There is not a good correlation between the degree of portal hypertension and the risk of variceal bleeding (1,2). However¸ positive correlation between the height of intravariceal pressure and the risk of variceal bleeding exists (1). Large varices and varices with red spots indicate higher ntravariceal pressure (3, 4, 5).
About 30% of the patients may die during the first episode of variceal bleeding. In those who survive¸ rebleeding occurs in 60% of cases with mortality rate exceeding 30% (6, 7).
Endoscopic sclerotherapy (EST) is an efficient method of controlling bleeding from oesophageal varices (8, 9). But in 30% of the patients with massive acute variceal bleeding this cannot be interrupt by EST. In these cases rebleeding rate is high and the complications are frequent (10).
Introduction of mechanical endoscopic devices for treatment of varices (ligation by elastic rings, endo-loops and hemoclips) eliminates systemic complications and significantly reduces local ailements of sclerotherapy. Endoscopic ligation is an efficient and safe method of treatment of oesophageal varices (10 - 13). Ligation by endo-loops is based on the same principles as ligation by rubber or elastic rings. The loops are 15 or 40 mm in diameter. Larger loops are used for ligation of gastric varices, where this method has some advantage over ligation by elastic rings (14).
The aim of this prospective study is to test the efficiency and safety of endoscopic oesophageal and gastric variceal ligation (EVL) by elastic rings and endo-loops in portal hypertension.
PATIENTS AND METHODS
This prospective study enrolled 32 patients with portal hypertension and oesophageal varices. Severity of liver disease was assessed by modified Child-Pugh's criteria. Eight (25%) patients actually bled, 20 (62.5%) had recent episodes of variceal bleeding¸ and 4 (12.5%) never bled before. Clinical symptoms and signs indicating variceal bleeding were as follow: hematemesis, blood in nasogastric aspirate, melena or hematochezia, orthostatic changes in blood pressure > 20 mm Hg or heart frequency > 20/min, systolic blood pressure <90 mm Hg, heart frequency >110/min and hematocrit decrease of 0.06 / 12h. Patients with active bleeding were resuscitated at first¸ and thereafter endoscopically examined. Variceal haemorrhage was defined when actually bleeding varix was seen. Recent variceal haemorrhage was when large varices were diagnosed and other source of bleeding excluded. Before varical ligation, every patient signed a consent and given an explanation on the treatment protocol. In case of bad general condition the treatment was done with family member consent.
Characteristics of 32 patients with oesophageal varices treated by endoscopic ligation with elastic rings (27 patients) and endo-loops (5 patients) are shown in table 1.
EVL by elastic rings was done with Pauldrach's ligation device, as described by Stiegmann (15). The ligation procedure was done under pharingeal anaesthesia by Xylocain spray, without any premedication, using the 25-cm-long overtube, which was placed into the proximal gullet.
EVL by endo-loops of 15 mm in diameter was done with nylon noose tightened around the varix by a special Olympus device. This consists of the applicator placed over the operational channel of the endoscope and the loops. After varical grasp, the loop was closed via the applicator handle. After the successful ligation, when the varix turned violet, the applicator was separated from the loop and pulled out, while the loop stayed in situ until the varix wrinkled and fell off together with the noose. Oesophageal tube was not used in ligation by endo-loops.
In patients with active variceal haemorrhage EVL were placed near the bleeding site at first. Then the ligation of all the other varices was further proceeded. At each treatment session ligation was started 1-2 cm above the oesophagogastric junction, and then the procedure was carried on 4-5 cm further ups, with the ligation of all the variceal vessels. Ligation was repeated in the intervals of 7-14 days, until the complete variceal obliteration was achieved or varices were reduced to grade I. After that, endoscopic examinations were made every 3 months, when newly formed varices were ligated.
The first session of EVL was done in hospital while the following interventions were mainly done on an outpatient basis. One or two days after the ligation¸ liquid food was advised. During the whole period of EVL, the patients were given H 2 receptor antagonists.
RESULTS
One quarter of the patients (25%) actively bled from varices at the beginnning of this study. One was in class A of Child-Pugh's classification, 5 in class B and 3 in class C. They all had oesophageal varices of grade III-IV, with red spots. Haemostasis of the active variceal haemorrhage was achieved in all 8 (100%) patients with either 1 or 2 ligatures. There were no recurrent bleeding before variceal eradication was achieved.
Variceal eradication was accomplished in 31 (96.8%) patients. In the case of a woman with HCV cirrhosis, after the first variceal ligation further procedures were cancelled because of ongoing liver failure. The average number of sessions neccessary for the variceal eradication was 2.70.7 (range 1-4). This was achieved within 4.31.9 weeks (range 2-8). The average number of applied ligatures per session was 5.11.4 (range 2-10). In total, 86 EVL sessions with 440 applied ligatures were performed.
During the average follow-up of 15 months, in 4 patients (12.5%) oesophageal variceal recurred thus neccesitating repeated ligation. After their eradication variceal bleeding did not repeat.
Three patients (9.3%) died because of ongoing liver failure (n = 2) and hepatocellular carcinoma (n = 1). None of the patients died of variceal bleeding (table 2).
There were no major complications of EVL. Only minor and transient phenomenon like retrosternal pain, dysphagia, shore throat¸ and fever were recorded. In the majority of patients (90.6%), when necrotic ligated varices were detached¸ wide and shallow non - bleeding ulcerations remained. After loop ligations. these ulcerations were of lesser degree. No patients developed oesophageal structure. Pulmonary, mediastinal or systemic complications were not encountered (table 3).
The patients accepted loop ligations better than EVL by elastic rings, primarily because of the absence of the overtube. In addition, a better visualisation of the varix was achieved during loop ligations because of the transparency of the ring placed at the top of the endoscope.
In 25 (78.1%) patients different grades of portal gastropathy were diagnosed. Portal gastropathy was classified as mild in the case of endoscopically verified mosaic mucosal appearance, and severe in the case of red or red-brown spots. After oesophageal variceal obliteration, 2 patients (6.2%) demonstrated an aggravation of the portal gastropathy; 2 (6.2%) developed gastric varices.
DISCUSSION
This study confirms the haemostatic efficacy of EVL in controling actively bleeding oesophageal varices. Our result coresponds with already published figures of oesophageal variceal bleeding control by EVL which is 86-100% (12, 16-18). We demonstrated that EVL is efficient as EST when varices actually exaguinate (10,13). On the contrary¸ some authors reported better control of variceal bleeding with EVL (86%) than with EST (77%) (12).
The EST success in the primary prophylaxis of variceal bleeding varies between the different centers. Paquet and Koch reported that EST reduces the frequency of haemorrhage and mortality¸ but not overall surival (19¸20). On the contrary¸ Potzi did not find any beneficial effect of prophylactic EST on the frequency of the variceal haemorrhage or survival rate, while the complications were numerous (21). An renewed interest for prophylactic endoscopic treatment of varices was due to the low rate of EVL accidents (10). It was demonstrated that the patients with high-risk varices treated with preventive EVL had significantly lower bleeding and mortality rate in comparison with controls (22, 23). In our 4 patients (12.5%) with high-risk varices (large varices, red spots on varices), which never bled before, endoscopic ligation was applied as primary bleeding prophylaxis. During the follow-up no patient re - bled.
In our patients the variceal eradication was achieved in 96.8% cases, with average 2.7 treatment sessions for 4.3 weeks. The average number of ligatures per treatment session was 5.1. This result is in concordance with other reports whith variceal eradication in 70-100% of cases, with average 3 sessions and 6 ligatures per intervention (10, 13¸ 16, 17, 24-26). The EVL variceal eradication is comparable with EST, but the number of treatment sessions is significantly higher ( 10 ).
In our series before the complete variceal eradication or after full variceal obliteration variceal re-bleeding was not recorded. This is to cofnirm Sarin¸ and Djurdjevic. reports of low post - EVL variceal re-beleeding rate (6.4% and 7%) (12, 13¸ 16¸27). Recurrent bleeding is significantly rarer in patients treated by EVL than in those with EST (10). This may be caused by shorter time neccessary for EVL variceal eradication, smaller number of sessions, and reduced risk of bleeding from moe superficial ulcerations (27, 28).
Recurrent varices were recorded in 4 (12.5%) cases. This is in accordance with the results of other authors which reported significant variceal re-growth between 10% and 40% depending on the time lapse which varied between 5.5 to 24 months (16¸24¸27¸29). The percentage of recurrent varices is significantly higher in EVL treated patients than in those who underwent EST (24, 27). This occures because during EVL perforated veins remain unoccluded (30).
In this series mortality rate was 9.3%. This result parallels already reported international figures with expected mortality between 10% and 28% depending on the period of observation which was 8 and 24 months (16, 23¸ 31). Some authors demonstrated the advantage of EVL over EST in relation to improved patient ¸ s survial due to the lower rate of recurrent haemorrhage and complications. This findings was refuted by other grups (12, 13, 18, 32). In Child - Pugh C patients EVL does not reduce rebleeding and mortality rate (33).
In our group of patients no seriuos systemic and local complications of EVL were observed. This is to further confirm the safety of this procedure due to limited oesophageal wall damage (16, 17, 27). EVL causes only mucosal and submucosal tissue injury (10). We noted high incidence of post - EVL ulcers (90.6%) which were symptomless. These ulcers were shallow and quickly subsided within two weeks (12, 28). On the contrary¸ post - EST ulcers are deeper and heal for about three weeks (12, 28, 29, 31, 34).
There are some reports about advantages of the combination of ligation and sclerosation over ligation alone (29, 35). Other studies did not confirm this finings in relation to the variceal eradication, recurrent varices, rebleeding and survival (17, 36, 37). Combined therapy protocol has even higher complication rate (17, 29, 35-37).
Post - EVL temporary bacteriemia occurs in 3-6% of the patients after the EVL (38, 39). This is the most probable reason for the fever in one of our patients (3,1%).
The most serious EVL complications occur because of the overtube use. They were not recorded in our patients. The overtube may produce a hematoma, bleeding¸ and esophageal perforation (40 - 42). These complications can be avoided by use of multiple-band ligation device, which does not require the use of the overtube (25). We used endo-loops ligations, which obviate the overtube use. This makes patients feel more comfortable and provides better visualisation of the top of the scope through the transparent ring. This procedure is shorter because pushing in and pulling out of the endoscope is unnecessary and provides good results in treating gastric variceal bleeding (10, 43, 44).
During the follow-up period after the variceal eradication we noted the aggravation of portal gastropathy in 6.2% of cases and gastric variceal increase in 6,2%. It was considered that portal gastropathy is of lesser degree after EVL than after EST. The rationale was because ligation does not occlude the perforating oesophageal veins thus leaving gastric microcirculatory congestion unaffected (10, 27). However, Lo's et al. demonstrated by endoscopic ultrasound a greater prevalence of paraesophageal and gastric varices after the EVL than after the EST (86% compared to 51% and 43% compared to 26%) (45). The same author reported that EVL can cause an increase of blood flow through the liver and stomach thus aggravating portal gastropathy mucosal changes (46). According to Sarin the impacts of EVL and EST on the occurrence of gastric varices are the same (8.8%) (27)
In conclusion, EVL an efficient and safe method of esophageal variceal treatment in portal hypertension. Ligation by endo-loops has advantage over ligation by elastic rings with Pauldrach's single-shot ligation device because of the absence of the overtube and better variceal visualisation. The occurrence of varices re - growth neccesitates regular endoscopic follow - ups after full variceal eradication. Further studies on the influence of EVL over the portal gastropathy and gastric varices are necessary.
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