Are sounds from mechanical heart valves equal for different valve types?

Area of Science:

• Biomedical Engineering
• Acoustics
• Cardiovascular Surgery

Background:

• Mechanical heart valves produce audible closing sounds.
• These sounds can cause patient distress, including sleep disturbances and social embarrassment.
• The perceived loudness may vary based on the specific valve prosthesis used.

Purpose of the Study:

• To investigate if the sound intensity of mechanical heart valve prostheses differs between valve types.
• To quantify the sound pressure levels (SPLs) generated by different mechanical heart valves.

Main Methods:

• Sound pressure levels (SPLs) were measured in dB(A) for three types of mechanical heart valves: ATS, Medtronic-Hall, and St. Jude Medical (SJM).
• Measurements were taken using a microphone positioned 5 cm above the chest of patients in a supine position within a bioacoustical laboratory.
• Data were collected from 15 patients with ATS valves, 29 with Medtronic-Hall valves, and 40 with SJM valves, all implanted in the aortic position.

Main Results:

• The mean SPLs were 43 ± 5 dB(A) for ATS valves, 41 ± 4 dB(A) for Medtronic-Hall valves, and 40 ± 4 dB(A) for SJM valves.
• A statistically significant difference in SPLs was observed between ATS and SJM valves (p < 0.05).
• ATS valves exhibited the highest mean SPLs, while SJM valves showed the lowest.

Conclusions:

• There is a statistically significant variation in sound pressure levels among different mechanical heart valve prostheses.
• The American-Trilogy-Sorin (ATS) valves generated the highest sound intensity, whereas St. Jude Medical (SJM) valves produced the lowest.
• Further correlation between objectively measured SPLs and patient-perceived annoyance is warranted.