How Can We Predict the Successful Outcome After Treatment in Achalasia Patients?

Typical symptoms of achalasia are dysphagia, regurgitation of undigested food, chest pain, weight loss and respiratory complications. In previous studies, esophageal manometry has been proposed as a useful test to determine whether patients should receive re-treatment. Decreased lower esophageal sphincter (LES) pressure to less than 10mmHg has been reported to be a good predictor of long-term treatment success.1,2 However, some achalasia patients with persistent symptoms after treatment had low or absent LES pressure.3,4 On the other hand, esophagogastric junction (EGJ) compliance is an important pathophysiological factor in the cases of achalasia and gastroesophageal reflux disease (GERD). A commercial measurement device, EndoFLIP system (endoscopic functional luminal imaging probe; Crospon, Galway, Ireland) was recently introduced to test compliance or distensibility of EGJ. The EndoFLIP uses impedance planimetry to determine multiple adjacent cross sectional areas (CSAs) within a cylindrical bag placed in a tubular organ during volumetric distention. The additional measure of the corresponding intrabag pressure allows assessment of the CSA pressure response (distensibility) of the distended area. Rohof et al5 performed the study to compare the EGJ distensibility and LES pressure as a better and more integrated parameter after treatment in the patients with achalasia. This study was performed in 15 healthy volunteers and 34 patients with achalasia. Healty volunteers underwent EndoFLIP measurement. Achalasia patients underwent esophageal manometry, EndoFLIP measurement of the EGJ, and timed barium esophagography. The symptoms were assessed using the Eckardt score. In 4 patients, the EndoFLIP probe could not pass the EGJ. Remained 30 achalasia patients could take the EndoFLIP test to estimate distensibility. Seven of the 30 patients were newly diagnosed and were measured before and 3 months after treatment. The authors included pneumodilation and laparoscopic Heller myotomy as the treatment options. The authors defined successful treatment as an Eckardt symptom score of ≤ 3. The 30 achalasia patients were divided into the successfully treated group (18 patients) and the treatment failure group (12 patients) by the Eckardt symptom score. Healthy volunteers had a mean EGJ distensibility of 6.3 ± 0.7mm2/mmHg using a 50mL volume distention. Untreated patients (0.7 ± 0.9mm2/mmHg; P < 0.001) had a significantlylower EGJ distensibility compared with healthy volunteers. The EGJ distensibility of both unsuccessfully treated and successfully treated patients was lower than that of healthy volunteers in a 50mL volume distention (1.6 ± 0.3mm2/mmHg; P < 0.01 and 4.4 ± 0.5mm2/mmHg; P = 0.02, respectively). In patients with achalasia, EGJ distensibility correlated with esophageal emptying (r=-0.72; P < 0.01) and symptoms (r = 0.61; P < 0.01) and was significantly increased with treatment. The patients with impaired distensibility and low LES pressure showed significantly more stasis on their timed barium esophagogram compared to the patients with normal distensibility and low LES pressure. The authors concluded EGJ distensibility is a better parameter than LES pressure for evaluating efficacy of treatment for achalasia. © 2012 The Korean Society of Neurogastroenterology and Motility.