The stethoscope: the forgotten instrument in cardiology?

Relationship between accurate auscultation of the fourth heart sound and the level of physician experience

BACKGROUND

Poor performance by physicians-in-training and interobserver variability between physicians has diminished clinicians' confidence in the value of the fourth heart sound (S4).

HYPOTHESIS

We sought to determine if accurate auscultation of an S4 improves with advancing levels of experience.

METHODS

We performed a prospective study of 100 patients undergoing left heart catheterization. Patients underwent blinded auscultation by 4 physicians (each from 1 of 4 different levels of experience), computerized acoustic cardiography, measurement of B-type natriuretic peptide (BNP) levels, echocardiography for measurement of left ventricular ejection fraction (LVEF), and cardiac catheterization for measurement of left ventricular end-diastolic pressure (LVEDP).

RESULTS

While cardiology fellows', residents', and interns' auscultatory findings demonstrated no significant agreement with acoustic cardiography, an S4 auscultated by cardiology attendings had moderate diagnostic accuracy with acoustic cardiography (odds ratio [OR]: 2.31; receiver-operating-characteristic [ROC] area: 0.60). The sensitivities of the S4 were low (39%-46%) for identifying patients with abnormal measures of left ventricular filling pressure (BNP and LVEDP, respectively), and the specificities were fair (76%-80%) with acoustic cardiography. The S4 was not associated with abnormal LVEF. None of the ausculatory groups performed as well as acoustic cardiography in separating patients based on objective measures of left ventricular filling pressure. Acoustic cardiography had the lowest (superior) negative likelihood ratios compared to any ausculatory group.

CONCLUSIONS

The S4 auscultated by cardiology attendings demonstrated superior diagnostic test characteristics compared with internal medicine housestaff and cardiology fellows. Correlations between the S4 and measures of ventricular filling pressure were superior for acoustic cardiography compared to the auscultator groups.

Teaching cardiac auscultation: effectiveness of a patient-centered teaching conference on improving cardiac auscultatory skills

OBJECTIVES

To assess the cardiac auscultatory skills of health care professionals before and after an actual (not simulated) patient-centered cardiac auscultation conference and to determine the effectiveness of this clinical teaching method on Improving diagnostic proficiency.

SUBJECTS AND METHODS

Seventy-eight participants at a conference on cardiac auscultation completed preconference and postconference examinations on their ability to diagnose a wide variety of heart sounds and murmurs. Among those tested, 46 (59%) were physicians: 17 (22%) were cardiologists, 19 (24%) were medical Interns or residents, 7 (9%) were cardiology fellows, 2 (3%) were general practitioners, and 1 (1%) was a pediatrician. Thirty-two (41%) of this group of respondents were nonphysicians: 14 (18%) were nurse practitioners, 9 (12%) were nurses, 6 (8%) were physician assistants, 2 (3%) were medical students, and 1 (1%) was a nonmedical professional. All participants were tested on 14 clinically Important cardiac auscultatory events directly recorded from actual (not simulated) patients and transmitted via wireless Infrared stethophones. The auscultatory events tested were wide physiologic splitting of S2 in right bundle branch block, fixed S2 splitting and systolic murmur in atrial septal defect, midsystolic click and late systolic murmur of mitral valve prolapse, S4 gallop, S3 gallop, opening snap of mitral stenosis, innocent systolic murmur, systolic murmur of mitral regurgitation, systolic murmur of tricuspid regurgitation, systolic murmur of hypertrophic obstructive cardiomyopathy, continuous murmur of patent ductus arteriosus, pericardial friction rub, prosthetic valve sounds, and alternation of heart sounds, heart murmurs, and the S3 gallop in congestive heart failure.

RESULTS

On the basis of the analysis of the 78 participants who completed preconference and postconference evaluations of the 14 selected cardiac auscultatory events, a preconference Identification score of 26.3% and a postconference score of 44.7% were observed. This represents a statistically significant overall Improvement in diagnostic proficiency (P < .001).

CONCLUSIONS

Cardiac auscultatory skills among today's health care professionals are extremely poor, regardless of the level and/or type of training of the professional. An actual (not simulated) patient-centered teaching conference is an effective clinical method of improving cardiac auscultatory skills and diagnostic proficiency of health care professionals.

Usefulness of the third heart sound in predicting an elevated level of B-type natriuretic peptide

Third heart sounds were sought in 100 consecutive outpatients who had B-type natriuretic peptide (BNP) levels measured within 8 hours. Mean BNP levels were significantly higher in those with a third heart sound. The presence of a third heart sound was 41% sensitive and 97% specific for elevated BNP levels.

W. Proctor Harvey: a master clinician-teacher's influence on the history of cardiovascular medicine

Medicine has become driven by research and technology, both of which have yielded indisputable benefits. Yet we are now so dependent upon such advancements that many practitioners have lost the basic clinical skills that enable bedside diagnosis. In the 2nd half of the 20th century, W. Proctor Harvey helped to keep alive the classic art of medicine.