Esophageal varices. I. Clinical presentation, medical therapy, and endoscopic therapy

Pathophysiology and Management of Variceal Bleeding

Cirrhosis is the fifth leading cause of death in adults. Advanced cirrhosis can cause significant portal hypertension (PH), which is responsible for many of the complications observed in patients with cirrhosis, such as varices. If portal pressure exceeds a certain threshold, the patient is at risk of developing life-threatening bleeding from varices. Variceal bleeding has a high incidence among patients with liver cirrhosis and carries a high risk of mortality and morbidity. The management of variceal bleeding is complex, often requiring a multidisciplinary approach involving pharmacological, endoscopic, and radiologic interventions. In terms of management, three stages can be considered: primary prophylaxis, active bleeding, and secondary prophylaxis. The main goal of primary and secondary prophylaxis is to prevent variceal bleeding. However, active variceal bleeding is a medical emergency that requires swift intervention to stop the bleeding and achieve durable hemostasis. We describe the pathophysiology of cirrhosis and PH to contextualize the formation of gastric and esophageal varices. We also discuss the currently available treatments and compare how they fare in each stage of clinical management, with a special focus on drugs that can prevent bleeding or assist in achieving hemostasis.

A Comprehensive Review of Portosystemic Collaterals in Cirrhosis: Historical Aspects, Anatomy, and Classifications

Portosystemic collateral formation in cirrhosis plays an important part in events that define the natural history in affected patients. A detailed understanding of collateral anatomy and hemodynamics in cirrhotics is essential to envisage diagnosis, management, and outcomes of portal hypertension. In this review, we provide detailed insights into the historical, anatomical, and hemodynamic aspects to portal hypertension and collateral pathways in cirrhosis with emphasis on the various classification systems.

N-butyl-2-cyanoacrylate, iso-amyl-2-cyanoacrylate and hypertonic glucose with 72% chromated glycerin in gastric varices

AIM: To compare n-butyl-2-cyanoacrylate, iso-amyl-2-cyanoacrylate and a mixture of 72% chromated glycerin with hypertonic glucose solution in management of gastric varices.

METHODS: Ninety patients with gastric varices presented to Endoscopy Unit of Ain Shams University Hospital were included. They were randomly allocated into three groups; each group included 30 patients treated with intravariceal sclerosant injections in biweekly sessions till complete obturation of gastric varices; Group I (n-butyl-2-cyanoacrylate; Histoacryl^®), Group II (iso-amyl-2-cyanoacrylate; Amcrylate^®) and Group III (mixture of 72% chromated glycerin; Scleremo^® with glucose solution 25%). All the procedures were performed electively without active bleeding. Recruited patients were followed up for 3 mo.

RESULTS: 26% of Scleremo group had bleeding during puncture vs 3.3% in each of the other two groups with significant difference, (P < 0.05). None of Scleremo group had needle obstruction vs 13.3% in each of the other two groups with no significant difference, (P > 0.05). Rebleeding occurred in 13.3% of Histoacryl and Amcrylate groups vs 0% in Scleremo group with no significant difference. The in hospital mortality was 6.6% in both Histoacryl and Amcrylate groups, while it was 0% in Scleremo group with no significant difference. In the first and second sessions, the amount of Scleremo needed for obturation was significantly high, while the amount of Histoacryl was significantly low. Scleremo was the less costly of the two treatments.

CONCLUSION: All used sclerosant substances showed efficacy and success in management of gastric varices with no significant differences except in total amount, cost and bleeding during puncture.

Role of endothelial nitric oxide synthase in the development of portal hypertension in the carbon tetrachloride-induced liver fibrosis model

Portal hypertension (PHT) is a complication of liver cirrhosis and directly increases mortality and morbidity by increasing the propensity of venous hemorrhage. There are two main underlying causations for PHT, increased hepatic resistance and systemic hyperdynamic circulation. Both are related to localized aberrations in endothelial nitric oxide synthase (eNOS) function and NO biosynthesis. This study investigates the importance of eNOS and systemic hyperdynamic-associated hyperemia to better understand the pathophysiology of PHT. Wild-type and eNOS(-/-) mice were given the hepatotoxin CCl(4) for 4-12 wk. Hepatic fibrosis was determined histologically following collagen staining. Portal venous pressure, hepatic resistance, and hyperemia were determined by measuring splenic pulp pressure (SPP), hepatic portal-venous perfusion pressure (HPVPP), abdominal aortic flow (Qao), and portal venous flow (Qpv). Hepatic fibrosis developed equally in wild-type and eNOS(-/-) CCl(4)-exposed mice. SPP, Qao, and Qpv increased rapidly in wild-type CCl(4)-exposed mice, but HPVPP did not. In eNOS(-/-) CCl(4) mice, Qao was not increased, SPP was partially increased, and HPVPP and Qpv were increased nonsignificantly. We concluded that the systemic hyperemia component of hyperdynamic circulation is eNOS dependent and precedes increased changes in hepatic resistance. Alternative mechanisms, possibly involving cyclooxygenase, may contribute. eNOS maintains normal hepatic resistance following CCl(4)-induced fibrosis. Consequently, increased portal pressure following chronic CCl(4) exposure is linked to hyperdynamic circulation in wild-type mice and increased hepatic resistance in eNOS(-/-) mice.

Role of cyclooxygenase isoforms in prostacyclin biosynthesis and murine prehepatic portal hypertension

Portal hypertension (PHT) is a common complication of liver cirrhosis and significantly increases morbidity and mortality. Abrogation of PHT using NSAIDs has demonstrated that prostacyclin (PGI(2)), a direct downstream metabolic product of cyclooxygenase (COX) activity, is an important mediator in the development of experimental and clinical PHT. However, the role of COX isoforms in PGI(2) biosynthesis and PHT is not fully understood. Prehepatic PHT was induced by portal vein ligation (PVL) in wild-type, COX-1(-/-), and COX-2(-/-) mice treated with and without COX-2 (NS398) or COX-1 (SC560) inhibitors. Hemodynamic measurements and PGI(2) biosynthesis were determined 1-7 days after PVL or sham surgery. Gene deletion or pharmacological inhibition of COX-1 or COX-2 attenuated but did not ameliorate PGI(2) biosynthesis after PVL or prevent PHT. In contrast, treatment of COX-1(-/-) mice with NS398 or COX-2(-/-) mice with SC560 restricted PGI(2) biosynthesis and abrogated the development of PHT following PVL. In conclusion, either COX-1 or COX-2 can mediate elevated PGI(2) biosynthesis and the development of experimental prehepatic PHT. Consequently, PGI(2) rather then COX-selective drugs are indicated in the treatment of PHT. Identification of additional target sites downstream of COX may benefit the >27,000 patients whom die annually from cirrhosis in the United States alone.

Interventional upper endoscopy: the pediatric perspective

Pediatric endoscopy has evolved from a purely observational modality into one with the potential for many therapeutic applications. Common therapeutic uses of endoscopy in children now include treatment of variceal bleeds and foreign body retrieval and newer procedures such as endoluminal gastroplication and endoscopic pyloromyotomy. Continuing research in pediatric endoscopy will allow pediatric gastroenterologists to perfect existing interventional endoscopic techniques and to learn to perform new ones.

Treatment of esophageal varices: a randomized controlled trial comparing endoscopic sclerotherapy and EUS-guided sclerotherapy of esophageal collateral veins

BACKGROUND

Endoscopic sclerotherapy (ES) and band ligation are standard treatments for esophageal varices. Unfortunately, recurrence is common and seems to be related to esophageal collateral vessels, easily identified by EUS. Eradication of these vessels might lead to a more durable therapeutic effect.

OBJECTIVE

To compare ES with EUS-guided sclerotherapy of collateral vessels (EUS-ES).

DESIGN

Randomized controlled trial.

SETTING

Endoscopy Unit, Division of Gastroenterology. Universidade Federal de São Paulo, São Paulo, Brazil.

PATIENTS AND INTERVENTIONS

Fifty cirrhotic patients with esophageal varices were randomized into 2 groups: ES (n = 25) and EUS-ES (n = 25). EUS-ES was targeted at collateral veins. Patients were followed-up for at least 6 months after eradication.

MAIN OUTCOME MEASUREMENTS

Efficacy in eradication, complications, and recurrence of varices.

RESULTS

Varices were eradicated in 48 patients who adhered to the study protocol. The mean (SD) number of sessions until eradication was 4.3 (1.5) for the ES group and 4.1 (1.2) for the EUS-ES group. In ES group, 4 patients had mild bleeding. In EUS-ES group, 4 patients had pain. The mean (SD) length of the follow-up period was 22.6 (6.9) months for the ES group and 24.9 (8.1) months for the EUS-ES group. Recurrence was seen in 4 patients after ES and in 2 after EUS-ES (P = .32). The presence of collateral vessels was associated with recurrence (P = .003).

CONCLUSION

EUS-ES is as safe and effective as ES in variceal eradication. Recurrence tends to be less frequent and occurs later. Persistence of esophageal collateral vessels after sclerotherapy is a risk factor for recurrence.

Equality of the left and right renal venous flow predicts the severity of variceal bleeding in portal hypertensive children

Portasystemic collaterals develop as a result of portal hypertension. The collaterals in the cardioesophageal region is the leading cause of bleeding from esophageal varices. Some of the portal hypertensive patients present with bleeding episodes but the others do not, and some of the bleeders do not respond to endoscopic sclerotherapy procedure, although the underlying pathology is the same. The capacity of the natural collateral vessels might be a determining factor about the hemorrhagic events. Since the first step of portasystemic collateralization takes place in the naturally existent vascular channels, the present study, with its anatomic and clinical parts, was focused on these venous structures.

The role of esophagogastroduodenoscopy in the diagnosis and management of upper gastrointestinal disorders

Esophagogastroduodenoscopy has revolutionized the clinical management of upper gastrointestinal diseases. Millions of EGDs are performed annually in the United States for many indications, such as gastrointestinal bleeding, abdominal pain, dysphagia, or surveillance of premalignant lesions. Esophagogastroduodenoscopy is very safe, with a low risk of serious complications such as perforation, cardiopulmonary arrest, or aspiration pneumonia. It is a highly sensitive and specific diagnostic test, especially when combined with endoscopic biopsy. Esophagogastroduodenoscopy is increasingly being used therapeutically to avoid surgery. New endoscopic technology such as endosonography, endoscopic sewing, and the endoscopic videocapsule will undoubtedly extend the frontiers and increase the indications for endoscopy.

Primary prophylaxis of variceal hemorrhage

Figure 3 shows an algorithm for the primary prevention of variceal hemorrhage. Pharmacologic therapy is the current standard of treatment for the primary prophylaxis of esophageal variceal bleeding. Patients with medium or large varices should be treated with a nonselective beta-blocker with the dose titrated to achieve a 25% decrement in resting heart rate or a heart rate of 55 to 60 bpm. The development of symptoms will, of course, limit the dose used. As discussed previously, these therapeutic endpoints are not well correlated with decreases in portal pressure. Measurement of the HVPG before therapy and after 3 months of therapy provides a rational approach to drug dosing. If the HVPG decreases by 20% or to less than 12 mm Hg, the medication dose will be effective in preventing hemorrhage. If, however, the HVPG is not appropriately lowered, a long-acting nitrate may be added. Patients with small varices should be observed, with endoscopic examinations every 2 years to assess progression of variceal size. Endoscopic therapy is not indicated for the primary prevention of variceal bleeding.

Portal hypertension

Many advances in the management of portal hypertension and variceal hemorrhage have occurred during the last 10 years. Effective therapy for primary prevention of variceal hemorrhage is now available in the form of nonselective beta-blockers. Active bleeding should be managed with terlipressin, somatostatin or its analogues, and endoscopic therapy; TIPS and surgery are reserved as salvage therapy for patients who fail endoscopic treatment. Survivors of a variceal hemorrhage should be evaluated for liver transplantation. Specific treatment may be provided with EVL while these patients await transplantation. Patients who fail endoscopic treatment may be treated by TIPS or surgery.