RESUMEN
BACKGROUND/AIMS: In patients with non-cardiac chest pain (NCCP), gastroesophageal reflux disease (GERD) is the commonest cause and ambulatory pH is of great value in identifying these patients. However, parameters in the context of predicting therapeutic response are still unknown. By extending the monitoring period, we could better evaluate the best evidence for GERD association. Our aims were (1) to compare the outcomes of 48-hour pH monitoring to 24-hour and (2) to determine whether objective parameters could predict the treatment success in patients with NCCP using Bravo pH system. METHODS: Pathological esophageal acid reflux (PEAR) and positive symptom index (SI) were calculated after 24-hour and compared to the 48-hour study. Evidence suggestive of GERD diagnosis was considered if PEAR and/or SI (+) were present on each different day. After pH study, all patients received proton pump inhibitor twice a day for 4 weeks. Treatment success was determined at the end of therapy. RESULTS: Thirty-two patients with NCCP participated. GERD was identified in 20 (62.5%) patients; 17 (53.1%) had PEAR, 3 (9.4%) SI (+) and 7 (22%) both. Twelve (41%) patients exhibited PEAR values on day 1, while 17 after 2 days; a 12.1% gain. SI (+) was found in 6 patients (18.8%) on day 1 and in 4 more on day 2, a gain of 12.5%. Significantly higher proportion of patients with GERD indicators showed improvement compared to those without (90% vs 16.7%, P < 0.005). CONCLUSIONS: In patients with NCCP, 48-hour pH measurement identified GERD as the cause of NCCP with an increased yield by almost 12% compared to 12 hours. Objective GERD parameters could predict response to antireflux therapy.