Question 1

What component of the conduction system is referred to as the pacemaker of the heart?

Accepted Answer

Specialized cells in the SA node near the superior vena cava initiate an electrical impulse. Because the SA node has an intrinsic rhythm, it is called the pacemaker of the heart. After the electrical impulse is initiated, it travels across the atria to the AV node where it is delayed slightly so the atria have time to contract before the ventricles are stimulated. Then the impulse travels to the bundle of His, the right and left bundle branches, and then through the ventricles.

Question 2

During an inspection of the precordium of an adult patient, the nurse notices the chest moving in a forceful manner along the sternal border. What does this finding most likely indicate?

Accepted Answer

This movement along the sternal border is an apical impulse. Normally the examiner may or may not see an apical impulse, but when visible, it occupies the fourth or fifth intercostal space at or inside the midclavicular line. A heave or lift is a sustained forceful thrusting of the ventricle during systole. It occurs with ventricular hypertrophy as a result of increased workload. A right ventricular heave is seen at the sternal border, as in this patient; a left ventricular heave is seen at the apex.

Question 3

In assessing a patient's major risk factors for heart disease, which would the nurse want to include when taking a history?

Accepted Answer

To assess for major risk factors of coronary artery disease, the nurse should collect data regarding elevated serum cholesterol, elevated blood pressure, blood glucose levels above 100 mg/dL or known diabetes mellitus, obesity, cigarette smoking, low activity level, and length of any hormone replacement therapy for postmenopausal women. Although heredity, or inherited DNA variation, and lifestyle factors each contribute independently to the development of coronary artery disease (CAD), a favorable lifestyle is associated with a 46% lower risk for CAD events than is an unfavorable lifestyle.

Question 4

The nurse is reviewing the anatomy and physiologic functioning of the heart. Which statement best describes what is meant by atrial kick?

Accepted Answer

Toward the end of diastole, the atria contract and push the last amount of blood (approximately 25% of stroke volume) into the ventricles. This active filling phase is called presystole, or atrial systole, or sometimes the atrial kick.

Question 5

The nurse is preparing to auscultate for heart sounds. Which technique is correct?

Accepted Answer

Auscultation of breath sounds should not be limited to only four locations. Sounds produced by the valves may be heard all over the precordium. The stethoscope should be inched in a rough Z pattern from the base of the heart across and down, then over to the apex; or, starting at the apex, it should be slowly worked up. Listening selectively to one sound at a time is best.

Question 6

While counting the apical pulse on a 16-year-old patient, the nurse notices an irregular rhythm. His rate speeds up on inspiration and slows on expiration. What should the nurse do?

Accepted Answer

This is sinus dysrhythmia which occurs normally in young adults and children. With sinus dysrhythmia, the rhythm varies with the person's breathing, increasing at the peak of inspiration and slowing with expiration. The nurse should document this as a normal finding. This is a normal finding so there is no need to question the patient about his caffeine intake, perform an electrocardiogram, or refer to a cardiologist.

Question 7

In assessing a 70-year-old man, the nurse finds the following: blood pressure 140/100 mm Hg; heart rate 104 beats per minute and slightly irregular; and the split S₂ heart sound. Which of these findings can be explained by the expected hemodynamic changes r/t age?

Accepted Answer

With aging, an increase in systolic blood pressure occurs. No significant change in diastolic pressure and no change in the resting heart rate occur with aging. Cardiac output at rest does not changed with aging.

Question 8

Which of these statements describes the closure of the valves in a normal cardiac cycle?

Accepted Answer

Events occur just slightly later in the right side of the heart because of the route of myocardial depolarization. As a result, two distinct components to each of the heart sounds exist, and sometimes they can be heard separately. In the first heart sound, the mitral component (M1) closes just before the tricuspid component (T1).

Question 9

What is the sac that surrounds and protects the heart is called?

Accepted Answer

The pericardium is a tough, fibrous double-walled sac that surrounds and protects the heart. It has two layers that contain a few milliliters of serous pericardial fluid. The myocardium is the muscular wall of the heart. The endocardium is the thin layer of endothelial tissue that lines the inner surface of the heart chambers and valves. The pleural space is the space between the visceral and parietal pleura of each lung. The sac that surrounds and protects the heart is the pericardium.

Question 10

The direction of blood flow through the heart is best described by which of these?

Accepted Answer

Returning blood from the body empties into the right atrium and flows into the right ventricle and then goes to the lungs through the pulmonary artery. The lungs oxygenate the blood, and it is then returned to the left atrium through the pulmonary vein. The blood goes from there to the left ventricle and then out to the body through the aorta.

Question 11

A 25-year-old woman in her fifth month of pregnancy has a blood pressure of 100/70 mm Hg. In reviewing her previous examination, the nurse notes that her blood pressure in her second month was 124/80 mm Hg. In evaluating this change, what does the nurse know to be true?

Accepted Answer

Despite the increased cardiac output, arterial blood pressure decreases in pregnancy because of peripheral vasodilatation. The blood pressure drops to its lowest point during the second trimester and then rises after that.

Question 12

What should the nurse do when assessing the carotid arteries of an older patient with cardiovascular disease?

Accepted Answer

If cardiovascular disease is suspected, then the nurse should auscultate each carotid artery for the presence of a bruit. The nurse should avoid compressing the artery, which could create an artificial bruit and compromise circulation if the carotid artery is already narrowed by atherosclerosis. Excessive pressure on the carotid sinus area high in the neck should be avoided, and excessive vagal stimulation could slow down the heart rate, especially in older adults. Palpating only one carotid artery at a time will avoid compromising arterial blood to the brain. The carotid pulse should be palpated medial to the sternomastoid muscle near the base of the neck (not the upper third).

Question 13

The mother of a 3-month-old infant states that her baby has not been gaining weight. With further questioning, the nurse finds that the infant falls asleep after nursing and wakes up after a short-time hungry again. What other information would the nurse want to have?

Accepted Answer

To screen for heart disease in an infant, the focus should be on feeding. Fatigue during feeding should be noted. An infant with heart failure takes fewer ounces each feeding, becomes dyspneic with sucking, may be diaphoretic, and then falls into exhausted sleep and awakens after a short -time hungry again. The infant's sleeping position, sibling history of eating disorders, and amount of background noise with eating are not r/t the symptoms this infant is experiencing. These symptoms are characteristic of heart disease.

Question 14

During an assessment of a 68-year-old man with a recent onset of right-sided weakness, the nurse hears a blowing, swishing sound with the bell of the stethoscope over the left carotid artery. What does this finding indicate?

Accepted Answer

A blowing, swishing sound heard over the carotid artery is a bruit. This sound indicates blood flow turbulence; normally none is present. It does not indicate a valvular disorder (that would be heard when auscultating the heart not the carotid artery), fluid volume overload or ventricular hypertrophy.

Question 15

Which sequence does the electrical stimulus of the cardiac cycle follow?

Accepted Answer

Specialized cells in the SA node near the superior vena cava initiate an electrical impulse. The current flows in an orderly sequence, first across the atria to the AV node low in the atrial septum. There it is delayed slightly, allowing the atria the time to contract before the ventricles are stimulated. Then the impulse travels to the bundle of His, the right and left bundle branches, and then through the ventricles.

Question 16

When listening to heart sounds, which valve closures are heard best at the base of the heart?

Accepted Answer

The second heart sound (S₂) occurs with the closure of the semilunar (aortic and pulmonic) valves and signals the end of systole. Although it is heard over all the precordium, the S₂ is loudest at the base of the heart.

Question 17

During an assessment of a healthy adult, where would the nurse expect to palpate the apical impulse?

Accepted Answer

The apical impulse should occupy only one intercostal space, the fourth or fifth, and it should be at or medial to the midclavicular line.

Question 18

The findings from an assessment of a 70-year-old patient with swelling in his ankles include jugular venous pulsations 5 cm above the sternal angle when the head of his bed is elevated 45 degrees. What does this finding indicate?

Accepted Answer

Because no cardiac valve exists to separate the superior vena cava from the right atrium, the jugular veins give information about the activity on the right side of the heart. They reflect filling pressures and volume changes. Normal jugular venous pulsation is 2 cm or less above the sternal angle. Elevated pressure is more than 3 cm above the sternal angle at 45 degrees and occurs with heart failure.

Question 19

The nurse is examining a patient who has possible cardiac enlargement. Which statement about percussion of the heart is true?

Accepted Answer

Numerous comparison studies have shown that the percussed cardiac border correlates only moderately with the true cardiac border. Percussion is of limited usefulness with the female breast tissue, in a person who is obese, or in a person with a muscular chest wall. Chest x-ray images or echocardiographic examinations are significantly more accurate in detecting heart enlargement.

Question 20

A 45-year-old man is in the clinic for a routine physical examination. During the recording of his health history, the patient states that he has been having difficulty sleeping. "I'll be sleeping great, and then I wake up and feel like I can't get my breath." Which is the best response by the nurse?

Accepted Answer

Paroxysmal nocturnal dyspnea (shortness of breath generally occurring at night) occurs with heart failure. Lying down increases the volume of intrathoracic blood, and the weakened heart cannot accommodate the increased load. Classically, the person awakens after 2 hours of sleep, arises, and flings open a window with the perception of needing fresh air. Although the symptom the patient is describing is likely r/t heart failure, asking when his last electrocardiogram was is not as important as finding out about a history of heart problems. These symptoms are not associated with a sinus or upper respiratory infection.

Quiz 20: Heart and Neck Vessels