Impact of Phonocardiography on Standardized Auscultation Assessment Performance by Medical Students
Abstract
Background: Phonocardiography (PCG) integrated into the stethoscope is now available (Eko Devices Inc, Oakland) for point of care assessment. ID of diastolic murmurs by auscultation is often more challenging compared to other sounds. We evaluated the incremental benefit of concomitant PCG data on ID of murmurs/rubs/gallops (MRG) by third year medical students.
Methods: Third year medical students completed a standardized auscultation assessment after their internal medicine rotation. Sound files of 10 MRGs (5 valvulopathies, 2 gallops, 1 CFR, 1 ventricular septal defect and 1 split S2) with a corresponding clinical vignette and physical exam location were provided with and without PCG (with interchangeable question stems) as 10 paired questions (20 total questions). Discrimination/difficulty indexes, chi-squared and McNemar test p-values were calculated for comparison between the two groups.
Results: Addition of PCG to audio data was associated with a statistically significant higher frequency of ID of mitral stenosis, S4 and CFR but lower ID rate of ventricular septal defect, S3 and tricuspid regurgitation; however individual question-specific statistics (discrimination/difficulty index) varied.
Conclusion: The utility of PCG as an adjunct to murmur auscultation is mixed. PCG may improve ID of diastolic murmurs and rubs, but this association was not observed with ID of systolic murmurs.
