Question 1

A cardiac arrhythmia that is life threatening and provides no effective cardiac output is&#10;A) atrial fibrillation.&#10;B) V-tach.&#10;C) V-fib.&#10;D) PVC.

Accepted Answer

V-fib (ventricular fibrillation) is a chaotic and disorganized electrical activity in the ventricles, resulting in an ineffective pumping of blood. This rapidly leads to cardiac arrest and must be treated immediately with defibrillation. Atrial fibrillation (A) may be life-threatening in certain circumstances, but typically it does not result in complete loss of cardiac output. V-tach (B) and PVCs (D) can also be life-threatening arrhythmias, but they do not result in complete loss of cardiac output like V-fib.

Question 2

Adequate perfusion of human tissue generally requires&#10;A) a diastolic pressure of 20 mm Hg.&#10;B) a systolic pressure of 90 mm Hg or greater.&#10;C) occasional arrhythmias to bring the heart into a rhythmic cardiac cycle.&#10;D) a diastolic pressure of at least 90 mm Hg.

Accepted Answer

Adequate perfusion of human tissue generally requires a systolic pressure of 90 mm Hg or greater. The diastolic pressure is also important, but it is not the only factor in determining adequate tissue perfusion. Occasional arrhythmias are not necessary for perfusion and a diastolic pressure of at least 90 mm Hg is not always required.

Question 3

All of the following are related except&#10;A) AV node.&#10;B) Purkinje fibers.&#10;C) SA node.&#10;D) myocardium.

Accepted Answer

The AV node, Purkinje fibers, and SA node are all components of the electrical conduction system of the heart, while the myocardium is the muscular tissue of the heart responsible for its pumping action.

Question 4

A widened QRS complex on an ECG tracing could represent&#10;A) ventricular hypertrophy.&#10;B) ventricular-paced rhythm.&#10;C) pacemaker tissue that is below the AV node.&#10;D) All of the above

Accepted Answer

A widened QRS complex on an ECG tracing can result from ventricular hypertrophy, ventricular-paced rhythm, or if pacemaker tissue is located below the AV node, which causes a delay in conduction and a wider QRS complex. Therefore, all of these options are possible causes of a widened QRS complex.

Question 5

A dual-wire pacemaker places electrode tips in the&#10;A) right atrium and right ventricle.&#10;B) right and left ventricles.&#10;C) right and left atria.&#10;D) left atrium and left ventricle.

Accepted Answer

A dual-wire pacemaker has electrode tips placed in the right atrium and right ventricle, allowing for optimal coordination of the heart's contractions. The other choices do not reflect the placement of electrodes in a dual-wire pacemaker.

Question 6

If the PR interval is longer than normal on a typical ECG tracing,one can assume that&#10;A) the patient has tachycardia.&#10;B) the patient has tachycardia.&#10;C) the patient has an AV node block.&#10;D) the patient has bradycardia.

Accepted Answer

A longer than normal PR interval on an ECG tracing indicates a delay in conduction between the atria and ventricles, which is commonly seen in AV node block. It is not necessarily indicative of tachycardia or bradycardia.

Question 7

An effective method for treating select cardiac arrhythmias is the use of high-frequency alternating current to destroy strategic cardiac tissue and reroute the cardiac impulses generated.These procedures are known as

A) selective coronary angioplastic repairs.
B) cardiac ablation treatments.
C) cardiac thermoplastics.
D) cardiac valvular replacements.

Accepted Answer

The method described in the statement is known as cardiac ablation treatments. Selective coronary angioplastic repairs and cardiac valvular replacements do not involve the use of high-frequency alternating current to destroy cardiac tissue, and cardiac thermoplastics is not a recognized medical procedure.

Question 8

The QRS complex on a typical ECG represents&#10;A) depolarization of atrial muscle.&#10;B) depolarization of ventricular muscle.&#10;C) repolarization of ventricular muscle.&#10;D) repolarization of atrial muscle.

Accepted Answer

The QRS complex represents the depolarization of ventricular muscle, which leads to the contraction of the ventricles and the ejection of blood from the heart. The depolarization of atrial muscle is represented by the P wave, and the repolarization of ventricular muscle is represented by the T wave. Repolarization of atrial muscle is not typically visible on the ECG.

Question 9

The polarity that exists across a cardiac cell membrane is maintained by an active transport process known as&#10;A) automaticity.&#10;B) fibrillation.&#10;C) sodium-potassium ion pump.&#10;D) pinocytosis.

Accepted Answer

The sodium-potassium ion pump is responsible for the active transport of sodium and potassium ions across the cardiac cell membrane, which maintains the cell's resting membrane potential and ensures that the polarity is preserved. Choices A and B refer to abnormal cardiac rhythms, and pinocytosis is a type of endocytosis that is not relevant to maintaining the membrane potential.

Question 10

The cardiac arrhythmia of bradycardia generally involves abnormalities to the&#10;A) SA and AV nodes.&#10;B) Purkinje fibers of the left atrium.&#10;C) right coronary sinus.&#10;D) bundle of HIS.

Accepted Answer

Bradycardia, which refers to an abnormally slow heart rate, is often due to abnormalities in the SA (sinoatrial) and AV (atrioventricular) nodes. These nodes are responsible for regulating the electrical signals that initiate each heartbeat and coordinate the contractions of the chambers of the heart. Abnormalities in these nodes can disrupt the normal rhythm of the heart and lead to bradycardia. The Purkinje fibers, right coronary sinus, and bundle of HIS do not typically play a major role in the development of bradycardia.

Question 11

For a cardiac cell to return to its resting membrane potential,&#10;A) repolarization of the cell membrane must occur.&#10;B) a nerve impulse must be initiated by the Purkinje fibers.&#10;C) depolarization of the cardiac cell membrane must occur.&#10;D) None of the above are correct.

Accepted Answer

The answer of For a cardiac cell to return to...

Question 12

Heart rates above 100 beats/min in an adult is termed&#10;A) bradycardia.&#10;B) tachycardia.&#10;C) cardiac ectopia.&#10;D) fibrillation.

Accepted Answer

The answer of Heart rates above 100 beats/min in an...

Question 13

A possible complication of patients with a history of atrial fibrillation is&#10;A) right coronary artery stenosis.&#10;B) left coronary artery stenosis.&#10;C) atrial emboli formation.&#10;D) AV node bundle block.

Accepted Answer

The answer of A possible complication of patients with a...

Question 14

Cardioversion therapy can be used to treat&#10;A) ventricular fibrillation.&#10;B) atrial-related arrhythmias.&#10;C) V-tach.&#10;D) All of the above

Accepted Answer

The answer of Cardioversion therapy can be used to treat&#10;A)...

Deck 16: Basic Cardiac Monitoring: the Electrocardiogram