The nurse is assessing a patient following a cardiac catheterization.

On assessment, they note muffled heart sounds, jugular vein distention, and hypotension.

The nurse knows these are signs of what?

Choice A rationale:

B-type natriuretic peptide (BNP) is a hormone produced primarily by the ventricles of the heart in response to stretching of the heart muscle fibers. It plays a crucial role in regulating blood volume and pressure by promoting the excretion of sodium and water by the kidneys. Elevated levels of BNP in the blood are strongly suggestive of heart failure, as the heart muscle is working harder to pump blood, leading to increased BNP production.

Key points supporting A as the correct answer:

BNP is a highly sensitive and specific marker for heart failure. Studies have demonstrated its accuracy in diagnosing heart failure, even in early stages when symptoms may be subtle.

The patient's clinical presentation aligns with heart failure. Vital fatigue and shortness of breath are both classic symptoms of heart failure, resulting from the heart's inability to meet the body's demands for oxygenated blood.

Other choices are less likely based on the information provided. Pleurisy (inflammation of the lining of the lungs), cardiomyopathy (disease of the heart muscle), and valve dysfunction can all cause shortness of breath, but they would not typically lead to elevated BNP levels unless heart failure is also present.

Additional considerations:

BNP levels can be influenced by factors other than heart failure, such as age, kidney function, and certain medications. However, in the context of a patient with typical heart failure symptoms, an elevated BNP level strongly supports the diagnosis.

BNP testing is often used to guide treatment decisions in patients with heart failure. Serial BNP measurements can help assess the effectiveness of therapy and monitor for disease progression.

Choice A rationale:

While an ICD can sometimes be used to treat bradycardia (an abnormally slow heart rate), this is not its primary function.

Pacemakers are more commonly used to manage bradycardia.

They work by continuously monitoring the heart's rhythm and delivering electrical impulses to the heart muscle when needed to maintain a normal heart rate.

Choice B rationale:

Atrial fibrillation (AFib) is a type of arrhythmia that causes the upper chambers of the heart (atria) to beat irregularly and rapidly.

ICDs are not typically used to treat AFib.

Instead, medications such as beta-blockers or calcium channel blockers are often used to control the heart rate and rhythm in patients with AFib. In some cases, a procedure called ablation may be used to destroy the areas of the heart that are causing the abnormal electrical signals.

Choice C rationale:

The primary purpose of an ICD is to detect and treat ventricular arrhythmias, which are potentially life-threatening rhythm disturbances that originate in the lower chambers of the heart (ventricles).

Ventricular fibrillation (VF) is a chaotic, rapid rhythm that prevents the heart from pumping blood effectively.

Ventricular tachycardia (VT) is a very fast heart rhythm that can also lead to cardiac arrest.

ICDs can deliver electrical shocks to the heart to restore a normal rhythm when these dangerous arrhythmias occur.

This can prevent sudden cardiac death (SCD).

Choice D rationale:

While an ICD can deliver a shock to the heart in the event of a heart attack, this is not its primary purpose.

It's important to note that an ICD cannot prevent a heart attack from happening; it can only treat the life-threatening arrhythmias that may result from a heart attack.