Cardiac Exam III: Abnormal Heart Sounds

1. Murmurs

1. Position the patient at a 30- to 45-degree angle on the examination table.
2. When auscultating a murmur, ask the patient to breathe in and out, as it can provide a vital diagnostic clue. Right-sided murmurs (pulmonary and tricuspid) are best heard on inspiration, as blood flows into the right ventricle when intrathoracic pressure decreases. Conversely, left-sided murmurs are heard best on expiration.
3. Categorize murmurs according to the following criteria: intensity (loudness), pitch (e.g., high or low, harsh or blowing), configuration (e.g., crescendo-decrescendo), location, and timing in the cardiac cycle (e.g., early systolic/diastolic).
4. Remember that not all murmurs are abnormal, and that systolic murmurs can be benign in younger people.
5. Also remember that each murmur is usually loudest at the anatomical area that corresponds with the valvular pathology.
6. Aortic stenosis: Auscultate with the diaphragm of the stethoscope on the aortic area, with the patient in supine position. Aortic stenosis is a harsh-sounding ejection systolic or crescendo-decrescendo murmur that occurs during systole, as the blood passes across the stenotic aortic valve. This murmur classically radiates to the carotid arteries and can be heard in the carotid area of the neck.
7. Aortic regurgitation: Auscultate with the diaphragm of the stethoscope at the lower left sternal border, close to the tricuspid area, with the patient leaning forward. The murmur of aortic regurgitation is a soft-blowing early diastolic decrescendo murmur. It can be associated with a number of other physical examination findings (described in step 5 below).
8. Mitral regurgitation: Place the diaphragm of the stethoscope on the mitral area. This murmur is a blowing pansystolic (or holosystolic) murmur. It classically radiates toward the axilla. Mitral valve prolapse can also be associated with a "mid-systolic click" sound.
9. Mitral stenosis: Auscultate with the bell of the stethoscope in the mitral area. It is a low-frequency rumbling mid-diastolic murmur and can be accentuated by laying the patient on his/her left side. Mitral stenosis is a very rare murmur that is almost always the result of prior rheumatic fever.
10. Right-sided murmurs: Remember that murmurs associated with the tricuspid and pulmonary valves are rare. Pulmonary stenosis, tricuspid regurgitation, and hypertrophic cardiomyopathy manifest as systolic murmurs. Tricuspid regurgitation occurs in association with longstanding lung disease, such as emphysema or pulmonary hypertension. Pulmonary regurgitation and tricuspid stenosis are diastolic murmurs. Congenital heart disorders, such as patent ductus arteriosus (PDA), can also cause loud murmurs. In the case of PDA, a continuous "machinery-like" murmur is auscultated.

2. Gallops (S3 and S4)

1. Auscultate for S3 and S4 in the mitral and tricuspid areas with the bell of the stethoscope pressed lightly on the patient's chest, and the patient lying on his/her left side.

3. Splitting of heart sounds:

The second heart sound can be "split" when the closure of the aortic and pulmonary valves do not occur together. The splitting of S2 during inspiration is normal and is known as physiological splitting (P2 occurs after A2). Fixed splitting can be heard with an atrial septal defect. If the splitting occurs during expiration, it is known as paradoxical splitting, which occurs when there is a prolonged left ventricular phase, such as in left bundle branch block or hypertrophic cardiomyopathy.

1. Ask the patient to breathe in and out, and auscultate over the second intercostal space at the left sternal edge.
2. Note at which phase of respiratory cycle the splitting occurs.

4. Rubs:

A pericardial friction rub, as seen in pericarditis, resembles a rubbing sound of two surfaces rubbing or grating against each other.

1. Auscultate at the lower left sternal edge with the patient leaning forward.

5. Note if the following signs of valvular pathology are present:

1. Quincke's pulse: seen in aortic regurgitation, resulting in alternating blanching and flushing of the nail bed.
2. Corrigan's pulse, also known as Watson's water hammer pulse: a collapsing pulse that occurs in aortic regurgitation.
3. de Musset's sign: a "bobbing" movement of the head, as seen with aortic regurgitation.
4. Blood pressure: a small gap between the systolic and diastolic blood pressure (narrow pulse pressure), frequently found in aortic stenosis. A wide pulse pressure is characteristic of aortic regurgitation.