Published online Feb 21, 2015. doi: 10.3748/wjg.v21.i7.2067
Peer-review started: April 23, 2014
First decision: May 29, 2014
Revised: June 20, 2014
Accepted: July 29, 2014
Article in press: July 30, 2014
Published online: February 21, 2015
Processing time: 294 Days and 18.5 Hours
AIM: To investigate crural diaphragm (CD) function in systemic sclerosis (SSc) using high-resolution manometry and standardized inspiratory maneuvers.
METHODS: Eight SSc volunteers (average age, 40.1 years; one male) and 13 controls (average age, 32.2 years; six males) participated in the study. A high-resolution manometry/impedance system measured the esophagus and esophagogastric junction (EGJ) pressure profile during swallows and two respiratory maneuvers: sinus arrhythmia maneuver (SAM; the average of six EGJ peak pressures during 5-s deep inhalations) and threshold maneuver (TM; the EGJ peak pressures during forced inhalation under 12 and 24 cmH2O loads). Inspiratory diaphragm lowering (IDL) was taken as the displacement of the EGJ high-pressure zone during the SAM.
RESULTS: SSc patients had lower mean lower esophageal sphincter pressure than controls during normal breathing (19.7 ± 2.8 mmHg vs 32.2 ± 2.7 mmHg, P = 0.007). Sinus arrhythmia maneuver pressure was higher in SSc patients than in controls (142.6 ± 9.4 mmHg vs 104.6 ± 13.8 mmHg, P = 0.019). Sinus arrhythmia maneuver pressure normalized to IDL was also higher in SSc patients than in controls (83.8 ± 13.4 mmHg vs 37.5 ± 6.9 mmHg, P = 0.005). Threshold maneuver pressures normalized to IDL were also greater in SSc patients than in controls (TM 12 cmH2O: 85.1 ± 16.4 mmHg vs 43.9 ± 6.3 mmHg, P = 0.039; TM 24 cmH2O: 85.2 ± 16.4 mmHg vs 46.2 ± 6.6 mmHg, P = 0.065). Inspiratory diaphragm lowering in SSc patients was less than in controls (2.1 ± 0.3 cm vs 3 ± 0.2 cm, P = 0.011).
CONCLUSION: SSc patients had increased inspiratory EGJ pressure. This is an add-on to EGJ pressure and indicates that the antireflux barrier can be trained.
Core tip: Crural diaphragm adaptation in systemic sclerosis may be an add-on to the antireflux barrier. This is an indication that the antireflux barrier can be trained. Our aim was to evaluate crural diaphragm function in systemic sclerosis using high-resolution manometry and standardized inspiratory maneuvers. Systemic sclerosis patients with severe esophageal disease have increased inspiratory esophagogastric junction pressure, despite a low normal-breathing lower esophageal sphincter pressure.