Methods and apparatuses for treating esophageal disorders such as gastroesophageal reflux disease are disclosed herein. One embodiment of a method includes applying energy to a portion of the sling and/or clasp fibers at the stomach, gastroesophageal junction, and/or esophagus of the patient in a manner that shortens or otherwise alters the fibers. The altered sling and/or clasp fibers are expected to recalibrate and restore the cardia and improve the competence of the lower esophageal sphincter. The energy applied to the fibers can be ultrasonic, radio-frequency, microwave, light, and/or other suitable types of energy.