The nurse is watching a client's cardiac monitor. The nurse recognizes that the QRS complex represents which phase of the cardiac cycle?
Atrial depolarization
Ventricular repolarization
Atrial repolarization
Ventricular depolarization
✓
Correct Answer
Ventricular depolarization
The QRS complex represents ventricular depolarization, which occurs as the electrical impulse moves through the ventricle to prompt contraction.
Question 2
Which of the following cardiac chambers pumps blood to the pulmonary artery and thus is prone to failure in clients with pulmonary arterial hypertension?
Right ventricle
✓
Left ventricle
Right atrium
Left atrium
Correct Answer
Right ventricle
The right ventricle pumps blood into the pulmonary artery and is subject to increased pressure in clients with pulmonary arterial hypertension.
Question 3
The nurse is caring for a client following a myocardial infarction. Which blood vessel does the nurse explain is blocked?
Aorta
Coronary vein
Coronary artery
✓
Vena cava
Correct Answer
Coronary artery
The coronary arteries supply the heart tissue with blood.
Question 4
A client is being sent to the cardiac catheterization laboratory after an acute myocardial infarction. During the procedure, a physician will puncture and enter the femoral artery to gain access to various heart structures. Which of the following differentiates arteries like the femoral artery from veins?
Arteries have a lower blood pressure in comparison to veins.
Arteries are lower risk during a puncture in comparison to veins.
Arteries carry oxygenated blood to the body for use by the tissues.
✓
Arteries carry deoxygenated blood back to the heart to be pumped to the pulmonary circuit.
Correct Answer
Arteries carry oxygenated blood to the body for use by the tissues.
With the exception of the pulmonary artery, all arteries carry oxygenated blood to various tissues for use.
Question 5
The left ventricle pumps blood from the heart to the aorta for use by the body. Which of the following processes occurs nearly simultaneously with left ventricular systole?
Right ventricular diastole
Right ventricular systole
✓
Right atrial systole
Excitation of the sinoatrial node
Correct Answer
Right ventricular systole
Both ventricles pump nearly simultaneously (ventricular systole). While the ventricles are pumping, both of the atria are filling (atrial diastole). The atria do not pump simultaneously with the ventricles.
Question 6
Which of the following carries an electrical signal from the atria to the ventricles in the healthy heart?
Purkinje fibers
Atrioventricular node
✓
Bundle of His
Sinoatrial node
Correct Answer
Atrioventricular node
The signal starts in the sinoatrial node and passes through the atrioventricular node to get to the ventricles. From there, it travels through the bundles of His and Purkinje fibers.
Question 7
Which of the following terms describes the ability of cardiac tissue to act as the pacemaker of the heart?
Automaticity
✓
Conductivity
Action potential
Membrane potential
Correct Answer
Automaticity
Automaticity is when the tissue is able to spontaneously generate an action potential, leading to spontaneous depolarization. Tissues with automaticity can act as the pacemaker of the heart.
Question 8
A client is admitted to the hospital with dizziness and shortness of breath. The provider orders an ECG. Which of the following can be diagnosed based on the results of the ECG?
Left ventricular systole
Heart failure with reduced ejection fraction
Atrial diastole
Dysrhythmia
✓
Correct Answer
Dysrhythmia
The ECG gives information about heart rhythm; abnormal rhythms are known as arrhythmias or dysrhythmias. Although some information about structural heart disease can be garnered from an ECG, other diagnostic methods such as echocardiography or biopsy would be needed to confirm the remaining diagnoses.
Question 9
The nurse is teaching a group of cardiac rehab clients about the electrical conduction of the heart. What statement made by a client best indicates the teaching is effective?
"The sinoatrial node is a specialized bundle of nerve tissue that causes ventricular contraction."
"The sinoatrial node is a specialized bundle of nerve tissue in the right atrium called the pacemaker of the heart."
✓
"The sinoatrial node is a specialized bundle of nerve tissue that repolarizes the ventricular myocardium."
"The sinoatrial node is a specialized bundle of nerve tissue that slows the electrical impulse."
Correct Answer
"The sinoatrial node is a specialized bundle of nerve tissue in the right atrium called the pacemaker of the heart."
The SA node, known as the pacemaker of the heart, has the property of automaticity and sends out electrical impulses 60–100 times/minute.
Question 10
A client is admitted with bradycardia detected by an ECG. Which statement describes bradycardia?
Heart rate less than 60 beats per minute
✓
Heart rate greater than 100 beats per minute
Heart rate greater than 60 beats per minutes
Heart rate less than 100 beats per minute
Correct Answer
Heart rate less than 60 beats per minute
Bradycardia describes a slow heart rate (less than 60 beats per minute), and tachycardia describes a fast heart rate (faster than 100 beats per minute).