About GERD
Gastroesophageal Reflux Disease (GERD) is the reflux of gastric contents back into the esophagus frequently enough to disrupt the quality of life for the patient. GERD occurs when the sling musculature of the GastroEsophageal Junction (GEJ) becomes stretched and loose, and the Angle of His is lost. The angle of His is the angle at which the base of the esophagus enters the stomach.
Although many definitions and criteria exist to describe gastroesophageal reflux disease (GERD), it is relatively universally recognized as having a deterioration of the normal anatomy as a causative factor in more advance disease beyond the level of mild clinical symptoms. It is easy to appreciate this fact when a demonstrable hiatal hernia is present; however, the beginnings of anatomic incompetence may be far more subtle and early in manifestation.
In a healthy individual, the tissue at the base of the esophagus doubles back as it enters the stomach, creating a double-layer of tissue that serves as a valve by resting against the lesser curve of the stomach. This valve opens during swallowing and then remains closed to prevent reflux of gastric contents into the esophagus. Reflux of gastric acid, pepsin and other enzymes and caustic agents irritate the squamous epithelium of the esophagus, and may lead to erosion and ulceration of esophageal mucosa.
Although a common physiologic mechanism for GERD exists in the observance of inappropriate transient lower esophageal relaxation which can result in a functionally incompetent lower esophageal sphincter (LES) exists for which the mechanism is still largely unknown, it is recognized that in moderate to more severe disease anatomy may be more important to remedying the problem[17]. Although a distinct annular sphincter can not be seen on pathology or histology, the LES appears to exist functionally as measured with esophageal manometry and may play a role in preventing reflux[17].
However, a more current view of GERD focuses on failure of the antireflux barrier and its primary component, the gastroesophageal valve (GEV). The understanding of the GEV has continued to progress in recent years, and more focus is currently being placed on the GEV, rather than the lower esophageal sphincter (LES) as the largest contributor to the anti-reflux barrier. In healthy patients, the Angle of His, the angle at which the esophagus enters the stomach, is intact creating a valve that prevents duodenal bile, enzymes, and stomach acid from traveling back into the esophagus where it can cause burning and inflammation of the sensitive esophageal. Proper function of the ARB to prevent reflux is dependent upon the geometry of the GEV. In healthy patients, the base of the esophagus extends into the stomach such that the Angle of His is maintained, and a 180-270 degree musculo-mucosal ridge is present. This ridge normally rests closed against the lesser curve of the stomach to prevent reflux of the stomach contents.
When the cardia sling musculature, formed by the collar sling musculature and clasp fibers found at the distal esophagus and proximal stomach, becomes stretched or attenuated, the Angle of His deteriorates into a funnel shaped GEJ and the GEV is lost. Some researchers have postulated that repeated proximal gastric distention causes permanent distortion of the collar sling and clasp fibers, which manifests as dilatation of the cardia, effacement of the angle of His, and formation of a funnel-shaped esophagogastric junction[17]. Further, the resultant anatomic derangement maybe more more susceptible to opening during increases in intragastric pressure[17]. As such, reflux may result because of the loss of the GEV, with or without a hiatal hernia, in the presence of dilation of the stomach or a consistent increase in intraabdominal pressure, such as with pregnancy or morbid obesity. Consequently, one of the major tenants of antireflux surgery is to restore normal geometry to the GEJ anatomy.
Citations:
[1] Reappraisal of the Flap Valve Mechanism in the Gastroesophageal Junction: A Study of a New Valvuloplasty Procedure in Cadavers, Thor, B.A., Hill Lucius D, Mercer, Dale D., and Kozarek, Richard D.; Acta Chir Scand 153: 25-28, ©1987
[2] Practice guidelines on the diagnosis, surveillance, and therapy of Barrett's esophagus. Sampliner R., Am J Gastroenterol 1998; 93: 1028-1032
[3] Efficacy of Medical Therapy and Antireflux Surgery to Prevent Barrett's Metaplasia in Patients With Gastroesophageal Reflux Disease, Gerold J. Wetscher, MD, Michael Gadenstaetter, MD, Paul J. Klingler, MD, Helmut Weiss, MD, Peter Obrist, MD, Heinz Wykypiel, MD, Alexander Klaus, MD, and Christoph Profanter, MD, Annals of Surgery Vol. 234, No. 5, 627-632 ©2001 Lippincott Williams & Wilkins, Inc.
[4] The Burden of Gastrointestinal Diseases, The American Gastroenterological Association, ©2001
[5] Cost-of-disease analysis in patients with gastro-oesophageal reflux disease and Barrett's mucosa. S. N. WILLICH, M. NOCON, M. KULIG*, D. JASPERSEN_, J. LABENZ, W. MEYER-SABELLEK, M. STOLTE-, T. LIND & P. MALFERTHEINER, Aliment Pharmacol Ther 23, 371-376. ©2006 The Authors 371Journal compilation 2006 Blackwell Publishing Ltd doi:10.1111/j.1365-2036.2006.02763.x
[6] The economic impact of GERD and PUD: examination of direct and indirect costs using a large integrated employer claims database. Vijay N Joish, Gary Donaldson, William Stockdale, Gary M Oderda, Joseph Crawley, Rahul Sasane, Sandra Joshua-Gotlib, Diana I Brixner. Curr Med Res Opin. 2005 Apr ;21:535-44.
[7] Quality of life for patients with gastroesophageal reflux disease 2 years after laparoscopuc fundoplication. S. Contini, A. Bertele, G. Nervi, R. Zinicola, C.Scarpignato. Surg. Endosc (2002) 16: 1555-1560.
[8] Surgery of Gastroesophageal Reflux Disease: A Competative or Complementary Procedure?, Lundell, Lars, Division of Surgery, Karolinska University Hsopital, Dig Dis 2004; 22: 161-170
[9] Laparoscopic Nissen Fundoplication, Glyn G. Jamieson, M.S., F.A.C.S., F.R.A.C.S., David I. Watson, M.B., B.S., F.R.A.C.S., Robert Britten-Jones, M.B., B.S., F.R.C.S., F.R.A.C.S., Philip C. Mitchell, M.D., F.R.C.S.C., and Mehran Anvari, M.B., B.S., F.R.C.S.C. From the University Department of Surgery, Royal Adelaide Hospital, Adelaide, South Australia; ANNALS OF SURGERY Vol. 220, No. 2, 137-145 ©1994 J. B. Lippincott Company
[10] Clinical Results of Laparoscopic Fundoplication at Ten Year After Surgery, Dallemagne, Bernard; CHC-Les Cliniques Saint Joseph, Digestive Surgery, Surg End
[11] Management of Gastroesophageal Reflux Disease, Joel J. Heidelbaugh, M.D., Timothy T. Nostrant, M.D., Clara Kim, M.D., and R. Van Harrison, PH.D., University of Michigan Medical School, Ann Arbor,Michigan, Am Fam Physician 2003;68:1311-8,1321-2. ©2003 American Academy of Family Physicians
[12] Efficacy of Medical Therapy and Antireflux Surgery to Prevent Barrett's Metaplasia in Patients With Gastroesophageal Reflux Disease. Wetscher, Gerold J. MD *; Gadenstaetter, Michael MD *; Klingler, Paul J. MD *; Weiss, Helmut MD *; Obrist, Peter MD +; Wykypiel, Heinz MD *; Klaus, Alexander MD *; Profanter, Christoph MD *. Annals of Surgery. 234(5):627-632, November 2001.
[13] Mixed Reflux of Gastric and Duodenal Juices Is More Harmful to the Esophagus than Gastric Juice Alone: The Need for Surgical Therapy Re-Emphasized. Werner K. H. Kauer, M.D., Jeffrey H. Peters, M.D., Tom R. DeMeester, M.D., Adrian P. Ireland, M.D., Cedric G. Bremner, M.D., and Jeffrey A. Hagen, M.D. Annals of Surgery Vol. 222, No. 4, 525-5333 ©1995 Lippincott-Raven Publishers
[14] The Cost of Long Term Therapy for Gastro-Oesophageal Reflux Disease: A Randomized Trial Comparing Omeprazole and Open Antireflux Surgery, Julkunen, K Levander, M Lamm, C Mattson, J Carlsson, N O Ståhlhammar and H E Myrvold, L Lundell, P Miettinen, S A Pedersen, B Liedman, J Hatlebakk, R, doi:10.1136/gut.49.4.488 Gut 2001;49;488-494.
[15] Short-term cost effectiveness and long-term cost analysis comparing laparoscopic Nissen fundoplication with proton-pump inhibitor maintenance for gastro-oesophageal reflux disease, R. Cookson1, C. Flood1, B. Koo, D. Mahon, and M. Rhodes, British Journal of Surgery 2005; 92: 700-706 Published by JohnWiley & Sons Ltd, ©2005 British Journal of Surgery Society Ltd
[16] Endoscopic treatment modalities for gastroesophageal reflux disease (GERD), B. H. A. von Rahden and H. J. Stein Department of Surgery, University Hospital, Paracelsus Private Medical University (PMU), Salzburg, Austria Received April 21, 2006; accepted July 17, 2006 © Springer-Verlag 2006, European Surgery.
[17] Endoscopic measurement of cardia circumference as an indicator of GERD (GERD), A. K. Seltman, P. J. Kahrilas, E. Y. Chang, M. Mori, PhD, J. G. Hunter, B. A. Jobe, Gastointestinal Endoscopy Vol. 63, No. 1 : 2006
