A 68-year-old man was diagnosed with systolic heart failure with normal ejection fraction and normal sinus rhythm at rest. A treatment with captopril was started. Which of the following actions most likely mediated the therapeutic effect of captopril in this patient?

Correct Answer: C

Rationale: Captopril is an ACE inhibitor that works by reducing preload and afterload on the heart, which helps improve symptoms of heart failure. By reducing preload, it decreases the amount of blood returning to the heart, and by reducing afterload, it decreases the resistance the heart has to pump against. This ultimately leads to improved cardiac function and symptom relief in patients with heart failure.

Correct Answer: C

Rationale: In this scenario, the correct answer is C) Verapamil. Propranolol, a beta-blocker, should not be prescribed for a patient with angina pectoris who is already receiving Verapamil, a calcium channel blocker. This combination can cause additive negative effects on the heart, such as excessive slowing of the heart rate and decreased cardiac contractility, potentially leading to serious cardiac complications. Nifedipine (Option A), Felodipine (Option B), and Isosorbide mononitrate (Option D) are not contraindicated with Propranolol in the context of treating angina pectoris. Nifedipine and Felodipine are also calcium channel blockers but belong to the dihydropyridine class, which does not have the same negative interactions with beta-blockers like Propranolol. Isosorbide mononitrate is a nitrate that is commonly used in combination with beta-blockers for managing angina. Educationally, understanding the interactions between different classes of cardiovascular drugs is crucial for safe and effective pharmacological management. It is essential for nurses to be aware of potential drug interactions to prevent adverse outcomes and to ensure optimal patient care. In this case, the rationale emphasizes the importance of knowing which drug combinations to avoid in patients with angina pectoris to prevent harmful effects on the cardiovascular system.

Correct Answer: A

Rationale: In the context of cardiovascular drugs in nursing pharmacology, understanding the effects of different stimulants on the heart is crucial for safe and effective patient care. In this question, the correct answer is A) Adrenaline. Adrenaline, also known as epinephrine, is the most potent stimulant for the heart due to its direct action on beta-1 adrenergic receptors in the heart. When adrenaline binds to these receptors, it increases heart rate, contractility, and conduction velocity, leading to a stronger and faster heartbeat. Noradrenaline (option B) primarily acts on alpha-1 adrenergic receptors, causing vasoconstriction rather than direct stimulation of the heart. Dopamine (option C) can stimulate both beta-1 and alpha-1 receptors depending on the dose used, but it is not as potent a stimulant for the heart as adrenaline. Ephedrine (option D) is a non-selective adrenergic agonist that acts on both alpha and beta receptors, but it is not as specific or potent for cardiac stimulation as adrenaline. Educationally, this question highlights the importance of understanding the pharmacological properties of different stimulants and their specific effects on the cardiovascular system. Nurses need to be able to differentiate between these drugs to make informed decisions in clinical practice, such as in emergency situations where a potent cardiac stimulant like adrenaline may be required. Understanding the mechanisms of action of these drugs also helps nurses anticipate and manage potential side effects and complications.

Correct Answer: A

Rationale: In teaching a client about ACE inhibitors, it is crucial to discuss potential side effects to promote awareness and adherence. The correct answer is A) Cough. ACE inhibitors commonly cause a dry, persistent cough due to increased bradykinin levels. This side effect can be bothersome but is typically not harmful and often resolves upon discontinuation of the medication. Option B) Bradycardia is incorrect because ACE inhibitors do not typically cause a slowing of the heart rate. In fact, they are more likely to have a neutral or even a beneficial effect on heart rate. Option C) Hypokalemia is also incorrect. While ACE inhibitors can lead to hyperkalemia (high potassium levels) in some cases, hypokalemia (low potassium levels) is not a typical side effect. Option D) Weight gain is not associated with ACE inhibitors. In fact, ACE inhibitors are more likely to have a neutral or even a slight diuretic effect that could lead to weight loss or maintenance. Educationally, understanding these side effects helps the client monitor for and report any concerning symptoms while taking ACE inhibitors. It also underscores the importance of medication adherence and the need for open communication with healthcare providers regarding any side effects experienced.

Correct Answer: B

Rationale: In cardiovascular nursing pharmacology, understanding electrocardiogram (ECG) segments like the QT interval is crucial for assessing cardiac function and identifying potential drug-induced arrhythmias. The correct answer, option B, states that the QT segment represents the total time for ventricular depolarization and repolarization. This is accurate because the QT interval on an ECG corresponds to the time it takes for the ventricles to depolarize and then repolarize, reflecting the electrical activity of the heart during a full heartbeat cycle. Option A, stating that the QT segment represents the time of atrial depolarization, is incorrect because the atrial depolarization is typically represented by the P wave on an ECG, not the QT segment. Option C is also incorrect as it combines atrial depolarization and repolarization, which are not represented by the QT interval. Option D, indicating ventricular depolarization only, is incorrect as the QT segment includes both depolarization and repolarization phases of the ventricles. Educationally, nurses need to grasp the significance of ECG intervals like the QT segment to accurately interpret cardiac rhythms, monitor for adverse drug effects that prolong the QT interval, and intervene promptly to prevent serious arrhythmias. Understanding the specific electrical events each ECG segment represents enhances nurses' ability to provide safe and effective care to patients receiving cardiovascular medications.