Recording esophageal heart sounds with a catheter-tip contact microphone.

The use of a catheter-tip microphone is described for the detection of heart sounds in the esophagus. The intensity and quality of the sounds differ from those detected on the precordium. Individual valve and breath sounds can be attenuated by choice of the location of the microphone in the esophagus. The acoustic shielding provided by the thorax allows presentation of heart sounds with little difficulty from acoustic feedback.