Experienced clinicians improve detection of third and fourth heart sounds by viewing acoustic cardiography

Abstract

Background: Clinical assessment of diastolic heart sounds is challenging. Hypothesis: We sought to examinewhether visual inspection of acoustic cardiographic tracings augments the accuracy of medical students' and physicians' detection of third and fourth heart sounds (S3, S 4) comparedto auscultation alone. Methods: A total of 90 adults referred for left heart catheterization underwent digital precordial heart sound recordings by computerized acoustic cardiography. Two blinded, experienced readers using a consensus method determined the presence of the S 3/S4 on each file. There were 35 subjects fromthe following 5 groups participating in this study from 1 teaching institution:first-year medical students (n = 5), fourth-year medical students (n = 5), interns (n = 5), medicine residents (n = 5), cardiology fellows (n = 5), and attendings (n = 10). Using a computer module, each subject listened to the heart sounds alone and documented whether an S3/S4 was present. Next, subjects listened to each recording in random order while viewing phonocardiographic tracings, and recorded S3/S4 presence. Results: An S3 was present in 21 patients (23%) and an S4 in 31 patients (34%) by consensus overread in 90 recordings. Baseline accuracy for auscultation of S3/S4 did not change with level of experience.While viewing the acoustic cardiogram, first-year medical students had minimal improvement in S3 (2%) and S4 (11%) accuracy. More experienced subjects improved S3 accuracy by 8% to 18% and S 4 by 15% to 32% (P