Optimizing Assessment of Contraction Reserve in Ineffective Esophageal Motility: A Study of Upright Multiple Rapid Swallows.

Background/aims: Multiple rapid swallows (MRS) is a provocative test during high-resolution esophageal manometry (HRM) to evaluate contraction reserve (CR). This study aims to determine the prevalence of CR in patients with ineffective esophageal motility (IEM) and MRS performed in the upright position, and to assess the ideal number of MRS sequences.

Methods: We enrolled adult patients diagnosed with IEM according to the Chicago classification version 4.0 who underwent HRM with 3 MRS sequences. Presence of CR was identified as either: the distal contraction integral (DCI) of the post-MRS sequence exceeding the mean DCI of single swallows (ratio > 1) or the mean DCI of the 3 post-MRS sequences surpassing the mean DCI of single swallows. The occurrence of CR was compared following 1, 2, and 3 MRS sequences.

Results: When assessing CR in 57 patients referenced to mean single supine swallow DCI, the pooled prevalence of CR following 1, 2, and 3 MRS sequences was 23/57 (40.4%), 31/57 (54.4%), and 33/57 (57.9%), respectively. More patients had CR after 2 MRS sequences compared to 1 ( < 0.001), but there was no significant difference in CR between 2 and 3 MRS sequences ( = 0.160). More patients had CR after 2 ( = 0.013) and 3 MRS sequences ( = 0.034) when CR was referenced to single upright compared to single supine swallows.

Conclusion: Among patients with IEM, 58.0% had CR after 3 upright MRS sequences and 2 were adequate to assess CR.