Interactive Guide to Physical Examination
Cardiovascular

Auscultation

Key principles for a successful exam:

  • Develop a systematic approach.
  • Listen selectively and specifically. Certain cardiac sounds must be "tuned out" (e.g. murmurs) while listening specifically to others (e.g. first and second heart sounds).
  • Identify the timing of sounds in relation to the cardiac cycle.
  • Understand and utilize patient positioning and respiratory maneuvers to evaluate findings.

Timing of auscultatory findings:

At heart rates under 120, diastole is longer than systole. At these rates it is fairly easy for the listener to identify S1 and S2, with systole being between them, and pairs of grouped S1s and S2s being separated by the longer diastolic interval. Identifying S1 and S2 correctly (and therefore systole and diastole) is imperative for correctly identifying the timing of other sounds/murmurs in the cardiac cycle.

With heart rates over 120, and with certain arrythmias, the duration of systole and diastole become indistinguishable. The timing of auscultatory sounds must therefore be determined by correlation with the carotid or apical impulse both of which occur in early systole just after S1.

Exam sequence and auscultation in the supine position:

Initially, auscultation should be conducted with the patient in the supine position, the head of the bed raised 15-30 degrees and the diaphragm of the stethoscope pressed firmly against the chest wall. Normal findings have been derived from this position. All other positions are considered "maneuvers" to further identify cardiac pathology. Auscultation should proceed in a systematic fashion from either apex to base or vice versa, as described in the video segment below.

View video Click on the video icon to view a demonstration and discussion of auscultation in the supine position.

The left lateral decubitus and upright position:

After the initial cardiac evaluation, patients should be examined in the left lateral decubitus position with the diaphragm and bell of the stethoscope. With the patient in this position, the examiner should listen specifically and selectively for a left-sided S3 or S4, and the diastolic rumble of mitral stenosis. These sounds may be found only in this position and heard only with the bell.

It is also important to listen in the upright position, along the left sternal border, noting any change in the character of murmurs found. In addition, to specifically evaluate for the diastolic murmur of aortic insufficiency or the presence of a friction rub, the examiner should auscultate while the patient leans forward and holds his/her breath in expiration. Other maneuvers will be covered under advanced cardiac techniques.

View video Click on the video for demonstration and discussion of auscultation in the left lateral and upright position.