Please identify the following rhythm: 
Asystole
Atrial Flutter
Normal Sinus Rhythm
Sinus Bradycardia
The Correct Answer is C
Answer and explanation
The correct answer is C. Normal Sinus Rhythm.
Choice A rationale:
Asystole is the absence of all electrical activity in the heart, as evidenced by a flat line on the electrocardiogram (ECG). It is a medical emergency that requires immediate cardiopulmonary resuscitation (CPR) and defibrillation.
Key features of asystole on ECG:
No discernible P waves, QRS complexes, or T waves.
A completely flat or nearly flat line on the ECG tracing.
Choice B rationale:
Atrial flutter is a rapid heart rhythm that arises from abnormal electrical activity in the atria. It is characterized by a sawtooth pattern on the ECG, with atrial rates typically between 250 and 350 beats per minute.
Key features of atrial flutter on ECG:
Absence of distinct P waves, instead replaced by flutter waves (sawtooth pattern).
Regular, rapid atrial rate (typically 250-350 bpm).
QRS complexes may be normal or slightly irregular in appearance.
Choice C rationale:
Normal sinus rhythm is the natural, healthy rhythm of the heart. It originates in the sinoatrial (SA) node, the heart's natural pacemaker, and is characterized by a regular rate of 60-100 beats per minute, with consistent P waves, QRS complexes, and T waves on the ECG.
Key features of normal sinus rhythm on ECG:
Presence of distinct P waves, QRS complexes, and T waves.
Regular rhythm with a rate of 60-100 beats per minute.
PR interval (the time between the P wave and QRS complex) is 0.12-0.20 seconds.
QRS duration (the time it takes for the ventricles to depolarize) is less than 0.12 seconds.
Choice D rationale:
Sinus bradycardia is a slow heart rhythm, with a rate below 60 beats per minute. It is often a normal finding in healthy individuals, especially athletes or during sleep. However, it can also be a sign of underlying medical conditions.
Key features of sinus bradycardia on ECG:
Presence of distinct P waves, QRS complexes, and T waves.
Regular rhythm with a rate less than 60 beats per minute.
PR interval and QRS duration are typically normal.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is C
Explanation
Choice A rationale:
Metoprolol (Lopressor) is a beta-blocker that primarily affects the heart and blood vessels. It does not have a direct effect on the visual system, and therefore, it is not associated with the green-yellow halo symptom.
Common side effects of metoprolol include:
Fatigue
Bradycardia (slow heart rate)
Hypotension (low blood pressure)
Dizziness
Cold extremities
Bronchospasm (narrowing of the airways)
Diarrhea
Tinnitus (ringing in the ears)
Decreased exercise tolerance
Glucose intolerance
Masking of hypoglycemia symptoms Choice B rationale:
Enalapril (Vasotec) is an angiotensin-converting enzyme (ACE) inhibitor that primarily affects the kidneys and blood vessels. It does not have a direct effect on the visual system, and therefore, it is not associated with the green-yellow halo symptom.
The most common side effect of enalapril is a dry cough. This cough is thought to be caused by an increase in bradykinin levels, which can lead to the constriction of bronchial smooth muscle.
Choice D rationale:
Furosemide (Lasix) is a loop diuretic that primarily affects the kidneys and fluid balance. It does not have a direct effect on the visual system, and therefore, it is not associated with the green-yellow halo symptom.
Toxicity with furosemide manifests as extensions of its diuretic activity. Signs and symptoms of overdose or toxicity include:
Dehydration
Reduced blood volume
Electrolyte imbalances, particularly hypokalemia (low potassium levels) Choice C rationale:
Digoxin (Lanoxin) is a cardiac glycoside that affects the heart's electrical activity and muscle contractions. It has a narrow therapeutic index, meaning that there is a small difference between the therapeutic dose and the toxic dose.
One of the most characteristic signs of digoxin toxicity is a visual disturbance known as the "green-yellow halo sign." This symptom is thought to be caused by the inhibition of an enzyme in the retina called Na+/K+-ATPase.
Other common signs and symptoms of digoxin toxicity include:
Nausea and vomiting
Anorexia (loss of appetite)
Fatigue
Headache
Confusion
Arrhythmias (irregular heartbeats)
Correct Answer is ["C","D"]
Explanation
Choice A rationale:
The ST segment represents the period of time between ventricular depolarization and repolarization. Its elevation or depression can indicate myocardial ischemia or injury, but it's not directly related to normal sinus rhythm determination.
The PR interval, on the other hand, measures the time it takes for the electrical impulse to travel from the atria to the ventricles. While a normal PR interval is essential for normal sinus rhythm, its height relative to the ST segment is not a determining factor.
Choice B rationale:
The number of complexes in a 6-second strip can provide a quick estimate of heart rate, but it's not a definitive criterion for normal sinus rhythm. A normal heart rate in adults typically ranges from 60 to 100 beats per minute, which could correspond to 5-10 complexes in a 6-second strip. However, other factors, such as rhythm regularity and P wave morphology, must also be considered. Choice C rationale:
RR intervals that are relatively consistent are a hallmark of normal sinus rhythm. This indicates that the heart is beating at a regular pace, with equal time intervals between each QRS complex. In contrast, irregular RR intervals suggest dysrhythmia, such as atrial fibrillation or premature ventricular contractions.
Choice D rationale:
One P wave preceding each QRS complex is another essential feature of normal sinus rhythm. The P wave represents atrial depolarization, and its consistent presence before each QRS complex (which represents ventricular depolarization) indicates that the electrical impulse is originating in the sinoatrial (SA) node, the heart's natural pacemaker, and is propagating through the atria and ventricles in a coordinated manner.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today