Published online Feb 26, 2020. doi: 10.12998/wjcc.v8.i4.723
Peer-review started: November 22, 2019
First decision: December 23, 2019
Revised: December 26, 2019
Accepted: January 19, 2020
Article in press: January 19, 2020
Published online: February 26, 2020
Processing time: 96 Days and 6.9 Hours
Little is known about the clinical significance of upper esophageal sphincter (UES) motility disorders and their association with the treatment response of type II achalasia. None of the three versions of the Chicago Classification of Esophageal Motility Disorders has defined UES abnormality metrics or their function. UES abnormalities exist in some patients and indicate a clinically significant problem in patients with achalasia.
We analyzed the types of UES abnormalities present and their frequency in consecutive patients with esophageal motility disorders undergoing HREM according to the current Chicago classification. We also determined the association between common clinical symptoms and UES abnormalities. Finally, we assessed the treatment-induced changes in LES and UES objective parameters to evaluate the treatment response among subjects with achalasia and UES dysfunctions.
The research objectives of this study were to demonstrate the manometric differentiation on high-resolution esophageal manometry between subjects with abnormal UES and normal UES, and the association between UES type and the treatment response of type II achalasia.
In total, 498 consecutive patients referred for high-resolution esophageal manometry were analyzed retrospectively. Patients were divided into those with normal and abnormal UES function. UES parameters were analyzed after determining lower esophageal sphincter (LES) function. Patients with type II achalasia underwent pneumatic dilation for treatment. Using mixed model analyses, correlations between abnormal UES and treatment response were calculated among subjects with type II achalasia.
Of the 498 consecutive patients, 246 (49.40%) were found to have UES abnormalities. Impaired relaxation alone was the most common UES abnormality (52.85%, n = 130). The incidence rate of type II achalasia was significantly higher in subjects with abnormal UES than those with normal UES (9.77% vs 2.58%, P = 0.01). After pneumatic dilation, LES resting pressure, LES integrated relaxation pressure, and UES residual pressure were significantly decreased (41.91 ± 9.20 vs 26.18 ± 13.08, 38.94 ± 10.28 vs 16.71 ± 5.65, and 11.18 ± 7.93 vs 5.35 ± 4.77, respectively, P < 0.05). According to the Eckardt score, subjects with type II achalasia and abnormal UES presented a significantly poorer treatment response than those with normal UES (83.33% vs 0.00%, P < 0.05).
Our study illustrates that UES abnormalities are frequently found on routine HREM. Impaired relaxation alone is the most common UES abnormality, followed by hypotension alone. The incidence of type II achalasia is associated with abnormal UES in the LES abnormal subgroup. A poorer treatment response of type II achalasia is seen with abnormal UES, which is potentially a prognostic indicator of treatment in this disease.
This article reflects a poorer treatment response of type II achalasia with abnormal UES, which is potentially a prognostic indicator of treatment in this disease. However, the limited number of achalasia patients in each category hindered us in analyzing treatment response in each subtype of achalasia. A prospective and multicenter study is necessary to obtain causal conclusions. In future HREM studies, a large number of subjects are needed to enroll to elucidate the relationship between treatment response and UES dysfunction in all achalasia subtypes and under other treatment methods.