A working group from the American Foregut Society reviewed and expanded the Hill grade classification to aid in the characterization and treatment of patients with gastroesophageal reflux disease.

“GERD is one of the most common chronic esophageal disorders, and endoscopy is one of the best ways to document the anatomic changes of the esophagogastric junction (EGJ) that are correlated with the presence of GERD. Therefore, it is important to have a user-friendly classification system that can document the anatomic findings of the EGJ during routine upper endoscopy,” said lead study author Ninh Nguyen, MD, the chief of the Division of Gastrointestinal Surgery at the University of California, Irvine. A white paper describing the new classification was published in Foregut (2022 Sep 28. doi:10.1177/26345161221126961).

The Hill grade is an endoscopic classification developed to grade the gastroesophageal flap valve, but its use has been suboptimal, explained Ronnie Fass, MD, the director of the Division of Gastroenterology and Hepatology and medical director of the Digestive Health Center at MetroHealth Medical Center, in Cleveland.

“Surgeons feel that the Hill classification is too subjective, that the interrater variability is too high,” Dr. Fass told Gastroenterology & Endoscopy News. “Even though the Hill classification has been around for many, many years, they feel that the focus of the Hill classification is only on the flap valve, where this new classification describes the whole esophagogastric junction.”

New Classification Includes 4 Grades

A team of 13 experts in foregut disease from gastroenterology and gastrointestinal surgery convened to review and update the Hill classification. After their review, the working group came to an agreement on the anatomy of the anti-reflux barrier.

“This group of experts agree that GERD is related to an impairment of the anti-reflux barrier, which is comprised of the flap valve, the crura of the diaphragm, and the lower esophageal sphincter and its gastric sling fibers,” Dr. Nguyen said (Figure 1). “Together, these three components contribute to the mechanical and physiologic barrier to reflux.”

Figure 1.

The new classification takes this pathophysiology into account and stratifies EGJ integrity across four grades (Figure 2). Grade 1 is normal, and grades 2 to 4 describe increasing degrees of EGJ disruption.

Figure 2.

While the Hill classification is based on visual characterization of the gastroesophageal flap valve seen via retroflexed endoscopy view, this new classification improves upon the Hill classification by not only taking into account the presence or absence of a flap valve “but also documenting the presence and degree of hiatal disruption,” Dr. Nguyen explained.

In addition to requiring examination for the presence or absence of a flap valve and measurement of the degree of hiatal disruption, to obtain an accurate assessment of the hiatus, the classification system requires full endoscopic insufflation and rotational provocative maneuvers in the retroflex view to elicit potential hiatal herniation.

“Since this new classification takes into account both the presence or absence of a flap valve and the degree of hiatus disruption, the final hiatus grade is based on the worse finding” of the two, Dr. Nguyen said. “A patient with 1.5-cm axial length hiatal hernia will automatically jump to a hiatus grade 3. In the Hill grade classification, you can observe a Hill grade 1 flap valve while also having a 1-cm hiatal hernia axial length. In this new classification, this scenario is not possible.”

Such “a comprehensive evaluation of the components of the reflux barrier is very important to planning structural repair,” said Christy Dunst, MD, an esophageal surgical specialist at the Oregon Clinic, in Portland. “This was less important decades ago when we had a one-surgery-fits-all approach with Nissen fundoplication. But now with advancements in techniques, the choice of repair can be tailored to the individual anatomy.”

Adoption of New Classification Will Take Time

Dr. Fass said he expects the new classification to become widely adopted, and he is already seeing it being incorporated into practice. “There’s going to be a process of adopting it. Some will still stick to the Hill classification, but I think as time goes by, more and more people will use the new classification and it will become the main classification on the heels of the Hill classification. If you look at the list of people that participated in the new classification’s development, it’s a combination of surgeons and gastroenterologists. The concept is that it will be used by both specialties.”

He predicted that the new classification “will be incorporated into a variety of therapeutic guidelines, for example, for gastroesophageal reflux disease. The expectation will be that before you send a patient for surgery, when you’re doing endoscopy, you will provide this information as part of the patient’s evaluation prior into reflux surgery. And not only in surgery but also, for example, endoscopic therapy for gastroesophageal reflux disease,” Dr. Fass said.

Dr. Nguyen said next steps include performing validation studies to understand the correlation between hiatus grade and the presence and degree of GERD and grading the hiatal appearance in patients who have undergone a prior anti-reflux intervention.

“My career has been dedicated to this topic for nearly 20 years. I love seeing the enthusiasm for this complex 2 inches of the human body,” Dr. Dunst said. “With more eyes investigating the intricacies of the interplay between the flap valve, the lower esophageal sphincter and the diaphragm, the field will advance with less invasive, more effective early treatments for millions of people suffering with GERD.”

—Jenna Bassett, PhD

Dr. Fass is a member of the Gastroenterology & Endoscopy News editorial board.