Ineffective Esophageal Motility (IEM): the Old-New Frontier in Esophagology.

Ineffective esophageal motility (IEM) is characterized by distal esophageal contraction amplitude of <30 mmHg on conventional manometry (Blonski et al. Am J Gastroenterol. 103(3):699-704, 2008), or a distal contractile integral (DCI) < 450 mmHg*s*cm on high-resolution manometry (HRM) (Kahrilas et al. Neurogastroenterol Motil. 27(2):160-74, 2015) in≥50 % of test swallows. IEM is the most common abnormality on esophageal manometry, with an estimated prevalence of 20-30 % (Tutuian and Castell Am J Gastroenterol. 99(6):1011-9, 2004; Conchillo et al. Am J Gastroenterol. 100(12):2624-32, 2005). Non-obstructive dysphagia has been considered to be frequently associated with severe esophageal peristaltic dysfunction. Defective bolus transit (DBT) on multichannel intraluminal impedance testing was found in more than half of IEM patients who presented with dysphagia (Tutuian and Castell Am J Gastroenterol. 99(6):1011-9, 2004), highlighting the functional defect of this manometric finding. Treatment of IEM has been challenging because of lack of promotility agents that have a definite effect on esophageal function.