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Heart sounds are altered by open cardiac surgery

Anita Hurtig-Wennlöf1, Christer Ahlstrom, Rigmor Egerlid

  • 1School of Health and Medical Sciences/Clinical Medicine, Orebro University, Orebro;

Experimental and Clinical Cardiology
|August 14, 2009
PubMed

Insights

Cardiac surgery alters heart sounds, with changes measurable by frequency shifts. These objective findings align with patient perceptions of changed heart sounds post-coronary artery bypass graft (CABG) surgery.

Area of Science:

  • Cardiology
  • Biomedical Engineering
  • Medical Acoustics

Background:

  • Patients report subjective changes in perceived heart sounds after open cardiac surgery.
  • Previous anecdotal evidence suggests alterations in heart sound characteristics post-procedure.

Purpose of the Study:

  • To quantitatively investigate and measure changes in heart sounds following coronary artery bypass graft (CABG) surgery.
  • To determine if subjective patient perceptions correlate with objective acoustic alterations.

Main Methods:

  • Heart sounds were recorded from 57 patients undergoing CABG surgery and 10 control subjects.
  • Analysis involved comparing Hjorth descriptors and main frequency peaks before and after surgery.
  • Statistical analysis was used to identify significant changes in acoustic parameters.

Main Results:

  • A significant alteration in the first heart sound was observed at a group level in patients post-CABG surgery.
  • Heart sounds generally shifted towards a lower frequency in the CABG group after the procedure.
  • No significant changes in heart sound characteristics were detected in the control group.

Conclusions:

  • Coronary artery bypass graft (CABG) surgery leads to objectively quantifiable alterations in heart sounds.
  • These acoustic changes may explain the subjective perceptions reported by patients.
  • The study confirms that heart sound modifications after CABG are measurable phenomena.
Abstract

Keywords:
Cardiac surgeryCounsellingHeart soundPhonocardiography

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