Increased inspiratory esophagogastric junction pressure in systemic sclerosis: an add-on to antireflux barrier.

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.