Increased mechanoreceptor sensitivity and hyperactive peristaltic responses to balloon distension in patients with non-cardiac chest pain (NCCP)

Background: Increased sensitivity of esophageal mechanoreceptors was supposed to develop in patients with NCCP.

Aims: The aim of this study was to measure the perception threshold of first sensation, discomfort and pain in 14 NCCP patients. Organic heart diseases were excluded by cardiologists. All NCCP patients underwent the following examinations: esophageal manometry, 24h pH-metry, simultaneous esophageal barostat+manometry. Patients were divided into two groups depending on the findings of 24h pH-metry: reflux group (N=7), non-reflux hypersensitive group (N=7). Semirandom ascending phasic esophageal distension was performed to test visceral sensitivity. Then the barostat was set to constant pressure (intrathoracic pressure + 10mm Hg) and 5 cc water was swallowed 10 times, and propagation amplitude and velocity was tested 5–10cm above (+) and under (-) the level of the distending balloon.

Results:

	First sensation	Discomfort	Pain
Reflux group	8±1mmHg	16±2mmHg	22±2mmHg
Sensitive group	7±1mmHg	11±1mmHg*	15±2mmHg*
Amplitude (mmHg)	+10cm	+5cm	–5cm	–10cm
Reflux group	86±4	98±5	60±4	67±3
Sensitive group	118±9*	132±8*	88±3*	89±6*

*: P<0.01 senstive vs. reflux group.

Conclusions: NCCP patients show visceral hypersensitivity. Decreased threshold to distension can be observed in non-reflux patients. Phasic motility of the esophagus during swallowing is increased secondary to an obstructive volume. This response is exaggerated in patients showing visceral hypersensitivity.

This work supported by the grants: OTKA F034433, ETT 550/2003.