Accepted Practice

Cardiac examination

Components of a cardiac examination include:

  • Review vital signs.
  • Look for signs of cardiovascular problems.
  • Inspect and palpate the neck for carotid pulses.
  • Auscultate the neck for bruits.
  • Inspect and palpate the precordium for pulsations.
  • Auscultate over the precordium at five auscultatory sites.

Review vital signs.

Before beginning a cardiac assessment, review your patient’s vital signs. Is his heart rate within normal limits, that is, between 60 and 100 beats per minute? Is his blood pressure within the normal range? Consider temperature and respiratory rate as well, as all the vital signs can relate to cardiovascular status. A fever may explain an increased heart rate, for example, or a patient may be short of breath with rapid, shallow respirations due to heart failure. Often, the patient’s weight is significant for a cardiac assessment as well. Poor cardiac output results in edema, or fluid collection in tissues, and monitoring weight is a more sensitive measurement of fluid retention than is checking for edema.

Look for signs of cardiovascular problems.

Turning your attention to the patient, note his overall condition. Does he appear comfortable or is he in pain? Is he having any difficulty breathing? Patients with chest pain or other cardiac problems often have shortness of breath. Note his level of consciousness: Is he alert and oriented? Consider his overall skin condition: Is his color consistent with his ethnicity, or is it pale or even bluish? Inspect and palpate his skin: Is it warm or cool? Moist or dry? Assess for clubbing of the nailbeds, which is due to inadequate supply of oxygenation in the peripheral system. This is seen in clients who have COPD, emphysema, and heart failure. Gently retract his lower eyelids to inspect the palpebral conjunctivae. They should be pink and moist, but with poor cardiac perfusion they may be pale, even in dark-skinned individuals.

Inspect and palpate the neck for carotid pulses.

Next, turn your attention to the patient’s neck. In the groove between the trachea and the sternocleidomastoid muscle, palpate the carotid arteries. (This and checking for jugulovenous distention are described in the neck portion of the physical examination.) To avoid disrupting blood flow to the brain, gently palpate one side at a time. Note the rate and rhythm of the carotid pulsations. Are the carotid pulses equal? Also, note the elasticity of the carotid arteries. Do they feel soft and pliable or stiff due to atherosclerosis?

Now, check for jugulovenous distention, or JVD. JVD is most common with heart failure, especially right-sided failure, but it can occur with anything that increases pressure in either the superior vena cava or the right atrium. Measure the client’s venous pressure by using two rulers to measure the vertical distance between the angle of Louis and the highest level of the visible point of the intercostal jugular vein pulsation. Repeat the measurement on the opposite side.

Auscultate the neck for bruits.

Then, using the bell of your stethoscope and light pressure, listen over the carotid arteries for bruits, heard as blowing or swishing sounds that reflect turbulent blood flow. For patients who have atherosclerosis, this is an especially important part of the exam. Depending on the length of the patient’s neck, you might listen at two or three places along the carotid artery for a careful assessment. If the patient’s breathing interferes with your ability to listen, ask the patient to hold his breath briefly for this part of the exam.

Inspect and palpate the precordium for pulsations.

Now turn your attention to the patient’s anterior chest wall, or precordium. Have the patient bare his chest. Inspect for an apical pulsation. This pulse, also called the point of maximal impulse (PMI) occurs as the apex of the heart bumps against the chest wall with each heartbeat. The apical impulse is not always visible and is more easily seen in patients who have thin chest walls or enlarged hearts, or in patients who are in high cardiac-output states, such as with exercise or fluid-volume overload. Having the patient sit upright or lean forward is useful, as it brings the heart closer to the chest wall. Breast tissue, of course, may make the PMI difficult to see. If the PMI is visible, be sure to note its location and size. Normally, the PMI is located near the fourth or fifth intercostal space near the left midclavicular line and covers an area no larger than that of a nickel. If the left ventricle is enlarged, as with left ventricular hypertrophy, the apical impulse may be visible over a larger area or displaced leftward or both. Be sure to inspect for pulsations all over the precordium and upper abdomen for any abnormal findings. Next, palpate the PMI. The PMI is usually palpable as a brief thump against your fingers. A pulsation that is so forceful it seems to “lift” your fingers upward is called a lift. A pulsation that feels rolling under your fingers is called a heave. Finally, use four fingers to palpate for a thrill, or vibration, over the PMI.

Palpate the rest of the precordium using the same sequence as for listening to heart sounds. If you choose to palpate the entire precordium, lay your fingertips lightly over each of the five precordial landmarks described in the auscultation sequence, as firm pressure can obliterate pulsations. Palpate each area for a pulsation and feel for any lifts, heaves, and thrills. Normally, you will feel no pulsations in these areas.

Auscultate over the precordium at five auscultatory sites.

Next, listen for heart sounds by auscultating with your stethoscope at each of the five precordial landmarks. These landmarks do not reflect anatomic sites per se, but are the places on the chest wall where you can best hear sounds from each heart valve. The aortic and pulmonic areas are both at the base of the heart. The aortic area lies in the second intercostal space at the right sternal border.

To find the second intercostal space, feel for the angle of Louis, where the manubrium joins the body of the sternum an inch or two below the sternal notch. The second ribs attach to the sternum at this level, and the second intercostal space is just below the second rib. Auscultating at this site is most useful for assessing the aortic valve. The next three listening points lie along the left sternal border. The pulmonic area, which is where you can best hear the pulmonic valve, is at the left base of the heart, located in the second intercostal space along the left sternal border.

Erb’s point can be found at the third intercostal space, one interspace below the pulmonic area. Erb's point does not reflect sound from one particular heart valve, but is a common listening post, lying halfway between the base and the apex of the heart.

Moving down to the fourth intercostal space along the left sternal border, you will find the tricuspid listening post, which is the best place to listen to the tricuspid valve.

The final listening post is the same site where you found the PMI – at the apex, normally located in the fifth intercostal space at the left midclavicular line.

Using the diaphragm of your stethoscope, listen over each of these posts. Listen for the first and second heart sounds. The first heart sound is the “lub,” which is also called S₁ and occurs when the tricuspid and mitral valves snap shut at the beginning of systole. S₁ is therefore loudest at the apex of the heart, over the tricuspid and mitral valves. The second heart sound, which is the “dub” or S₂, occurs when the aortic and pulmonic valves close at the beginning of diastole, and so S₂ is heard best at the base of the heart, at the aortic and pulmonic listening posts. At the second pulmonic area, S₁ and S₂ are typically equal in sound volume.

As you listen to heart sounds at each of these listening points, it is helpful to “inch” your stethoscope from one point to the next, rather than picking it up and setting it down again. That way, you can track the sounds as you move over the precordium. Concentrate on S₁ and S₂ and try to identify each. The best way to differentiate S₁ and S₂ is probably to concentrate on the rhythm. With a heart rate slower than 100 beats per minute, systole is noticeably shorter than diastole, so there will be a longer pause after S₂. Also, recall that S₂ is louder at the base while S₁ is louder at the apex. Yet another way to tell S₁ from S₂ is to palpate the carotid pulse while you listen over the precordium. S₁, which occurs at the beginning of systole, coincides with the carotid pulse. Are the patient’s heart sounds distinct and unified? Remember, each sound is generated by two valves closing, one on each side of the heart. If the valves do not close simultaneously, the heart sound may be split. For example, with a bundle branch block, electrical conduction to one side of the heart may be delayed, so the ventricles may not contract at the same time, causing a split S₁. A split heart sound may sound like a “stutter.” Listen for abnormal heart sounds, as well. You might hear an S3 following S₂, especially in patients who have congestive heart failure. S4, which immediately precedes S₁, is associated with hypertension, coronary artery disease, and often accompanies a myocardial infarction.

Be sure you listen to the spaces between S₁ and S₂ as well. This time in the cardiac cycle should be silent because the blood should be flowing smoothly through the heart valves. However, if a valve is stenotic, or does not open widely, blood may flow through it in a turbulent fashion, causing a whooshing or a swishing sound. This is a murmur. Likewise, if a valve is regurgitant or incompetent, that is, it does not close tightly, blood may leak backward through it, also causing a murmur. If you hear a murmur, notice where on the precordium it sounds loudest, and try to place the murmur in either systole or diastole. For example, you might hear a systolic murmur only in the aortic area. Murmurs are graded from grade 1 to grade 6 according to their loudness. Grade-1 murmurs are very difficult to hear, while you can hear a grade-6 murmur with the stethoscope lifted off the patient’s chest! Loud murmurs, grade 4 and above, are often accompanied by a palpable thrill. Repeat the sequence for cardiac auscultation using the bell of your stethoscope. Remember to use very light pressure when using the bell so you can identify low-pitched murmurs. S₃ and S₄ are low-pitched sounds so they are also heard better with the bell of the stethoscope.

Another alteration in cardiac assessment is the rare presence of a pericardial friction rub. Friction rubs may occur when the pericardium, the membrane surrounding the heart, becomes inflamed. This causes a high-pitched, scratchy sound similar to that of rubbing sandpaper together. Friction rubs can be heard throughout systole and diastole and are generally loudest over the apex of the heart. You will be more likely to hear a friction rub when you are using the diaphragm to listen to the PMI during the first portion of cardiac auscultation.

Listening to heart sounds takes concentration and practice. Be sure to reduce extraneous noises, and always remove the patient’s clothing so that you can place your stethoscope directly on the chest wall. You may find it helpful to close your eyes to concentrate on what you are hearing. If you have difficulty hearing heart sounds, ask the patient to change position to bring the heart closer to the chest wall.

You might have to ask him to sit upright and lean forward a bit or lie on his left side. Don’t hesitate to make these adjustments as necessary, so that your findings from this crucial assessment are as accurate as possible.