Characterization of Simultaneous Pressure Waves as Biomarkers for Colonic Motility Assessed by High-Resolution Colonic Manometry

Abstract

Simultaneous pressure waves (SPWs) in manometry recordings of the human colon have been associated with gas expulsion. Our hypothesis was that the SPW might be a critical component of most colonic motor functions, and hence might act as a biomarker for healthy colon motility. To that end, we performed high-resolution colonic manometry (HRCM), for the first time using an 84-sensor (1 cm spaced) water-perfused catheter, in 17 healthy volunteers. Intraluminal pressure patterns were recorded during baseline, proximal and rectal balloon distention, after a meal and following proximal and rectal luminal bisacodyl administration. Quantification was performed using software, based on Image J, developed during this study. Gas expulsion was always associated with SPWs, furthermore, SPWs were associated with water or balloon expulsion. SPWs were prominently emerging at the termination of proximal high amplitude propagating pressure waves (HAPWs); we termed this motor pattern HAPW-SPWs; hence, SPWs were often not a pan-colonic event. SPWs and HAPW-SPWs were observed at baseline with SPW amplitudes of 12.0 ± 8.5 mmHg and 20.2 ± 7.2 mmHg respectively. The SPW occurrence and amplitude significantly increased in response to meal, balloon distention and luminal bisacodyl, associated with 50.3% anal sphincter relaxation at baseline, which significantly increased to 59.0% after a meal, and 69.1% after bisacodyl. Often, full relaxation was achieved. The SPWs associated with gas expulsion had a significantly higher amplitude compared to SPWs without gas expulsion. SPWs could be seen to consist of clusters of high frequency pressure waves, likely associated with a cluster of fast propagating, circular muscle contractions. SPWs were occasionally observed in a highly rhythmic pattern at 1.8 ± 1.2 cycles/min. Unlike HAPWs, the SPWs did not obliterate haustral boundaries thereby explaining how gas can be expelled while solid content can remain restrained by the haustral boundaries. In conclusion, the SPW may become a biomarker for normal gas transit, the gastrocolonic reflex and extrinsic neural reflexes. The SPW assessment reveals coordination of activities in the colon, rectum and anal sphincters. SPWs may become of diagnostic value in patients with colonic dysmotility.

Intraluminal prucalopride increases propulsive motor activities via luminal 5‐HT4 receptors in the rabbit colon

“…When patients are unable to generate HAPWs, they are diagnosed to have “inert colon.” However, evaluating only HAPWs without considering other motor pattern configurations does not constitute a full assessment of colonic motility. We have advocated for the assessment of simultaneous pressure waves, in particular in conjunction with preceding HAPWs, as an essential component of colonic motor function evaluation . The present study shows that a 5‐HT 4 receptor agonist acting from the lumen can evoke the colonic motor complex in its various forms, that is, not only LDCs as the most forceful propulsive motor pattern in the rabbit colon but also several other configurations of propulsive motor patterns such as FPC clusters associated with pressure development.…”

“…The LDC in the rabbit colon has similarities to the propulsive contraction that produces the high‐amplitude propagating pressure wave (HAPW) in the human colon; in that, it is the most forceful propulsive motor pattern. The FPCs are likely the equivalent of rapidly propagating circular muscle contractions, a cluster of fast propagating contractions in humans that produces the simultaneous pressure waves (SPW) . Supporting evidence is provided by a previous study in the rabbit colon where spatiotemporal mapping of video‐recorded motor patterns was correlated with pressure waves obtained by simultaneously executed high‐resolution manometry .…”

“…With the emergence of high‐resolution colonic manometry (HRCM), efforts are underway to evaluate human motor patterns as clinical biomarkers of healthy colonic motor activity and colonic motor dysfunction . With high‐resolution manometry, colonic motility is evaluated as pressure patterns.…”

Luminal 5‐HT4 receptors—A successful target for prokinetic actions

“…Although relatively infrequent, these are the dominant propulsive motor pattern in human colon and are probably necessary for defecation. Absence of spontaneous or evoked HAPCs may identify abnormal colonic function contributing to constipation . Importantly, HRM has identified more frequently occurring simultaneous pressure waves (SPWs) which are difficult to discriminate with standard manometry.…”

Cell‐specific effects of nitric oxide on the efficiency and frequency of long distance contractions in murine colon

“…LDCs have a neurogenic component as they are abolished by TTX; they also have a myogenic component since they can be initiated in the presence of TTX by cholinergic agonists . LDCs are most likely the mouse equivalent to the high amplitude propagating contractions (HAPC) of the human colon …”