A 55-year-old patient who is diagnosed with an evolving myocardial infarction (MI) insists on going home. The cardiac-vascular nurse encourages the patient to be admitted because the greatest risk within the first 24 hours of sustaining an MI is:

Correct Answer: D

Rationale: The correct answer is D) ventricular fibrillation. Ventricular fibrillation is the most life-threatening complication that can occur within the first 24 hours of sustaining a myocardial infarction (MI). It is a chaotic, rapid, and ineffective heart rhythm that can lead to sudden cardiac arrest and death if not promptly treated with defibrillation. Option A) heart failure typically develops over a longer period following an MI and is not the greatest risk within the first 24 hours. Option B) pulmonary embolism is a potential complication post-MI but is not the most immediate risk compared to ventricular fibrillation. Option C) ventricular aneurysm can develop days to weeks after an MI and is not the most immediate risk within the first 24 hours. In an educational context, understanding the critical complications that can arise following an MI is essential for healthcare providers caring for these patients. Recognizing the signs and symptoms of ventricular fibrillation and knowing how to intervene promptly can significantly impact patient outcomes and reduce mortality rates associated with acute MI. It underscores the importance of early and continuous monitoring of patients with evolving MIs to prevent life-threatening complications.

Correct Answer: C

Rationale: In this scenario, the correct answer is C) Angiotensin II receptor blockers (ARBs). ARBs work by blocking the action of angiotensin II, a substance in the body that causes blood vessels to constrict, leading to increased blood pressure. By inhibiting angiotensin II, ARBs promote vasodilation, which helps lower blood pressure. Additionally, ARBs also enhance salt and water excretion, further aiding in the management of hypertension. Thiazide diuretics (option A) work by increasing the excretion of salt and water by the kidneys but do not specifically target the renin-angiotensin-aldosterone system like ARBs do. Direct vasodilators (option B) directly relax blood vessels to lower blood pressure but do not specifically target angiotensin II. Angiotensin-converting enzyme (ACE) inhibitors (option D) work by blocking the conversion of angiotensin I to angiotensin II, but ARBs act downstream by directly blocking the action of angiotensin II. In an educational context, understanding the mechanisms of action of different classes of antihypertensive medications is crucial for nurses and healthcare professionals in effectively managing patients with hypertension. Knowing the specific actions of ARBs in inhibiting angiotensin II can help in making informed decisions regarding medication selection and individualized patient care plans.

Correct Answer: C

Rationale: In this case, the most appropriate initial treatment plan for the 62-year-old woman with prehypertension, high LDL levels, and who smokes a pack of cigarettes per day would be option C) Diet therapy and smoking cessation. The rationale behind selecting option C is based on addressing the modifiable risk factors that are directly contributing to the patient's cardiovascular health. Diet therapy aims to lower LDL cholesterol levels through dietary modifications such as reducing saturated fat intake. Smoking cessation is crucial as smoking is a major risk factor for cardiovascular disease and quitting smoking can significantly reduce the risk of heart disease. Option A, which suggests diet and drug therapy, may be considered if lifestyle modifications alone are not effective in reaching treatment goals. However, in this scenario, focusing on lifestyle changes first is paramount. Option B, exercise instruction only, while beneficial for overall health, may not be as critical as addressing the high LDL levels and smoking in this patient with prehypertension. Option D, drug therapy and smoking cessation, could be considered if the patient's condition worsens or if lifestyle modifications alone are insufficient to manage her risk factors. Educationally, this question highlights the importance of addressing modifiable risk factors in cardiovascular disease management. It emphasizes the role of lifestyle modifications, such as diet therapy and smoking cessation, as foundational components of treatment before considering pharmacological interventions. This case underscores the significance of a holistic approach to patient care, focusing on prevention and lifestyle changes to improve cardiovascular health outcomes.

Correct Answer: C

Rationale: In the context of a patient presenting with chest pain and ST segment elevation on a second 12-lead ECG, the correct answer is C) MI associated with prolonged and complete coronary thrombosis. This finding typically indicates an acute myocardial infarction (MI) where there is prolonged and complete blockage of a coronary artery leading to ischemia and subsequent tissue damage. The ST segment elevation seen on the ECG is a key indicator of myocardial injury in the setting of an MI. Option A) Transient ischemia typical of unstable angina is incorrect because unstable angina usually presents with transient ST segment depression or T-wave inversion, not elevation. Option B) Lack of permanent damage to myocardial cells is incorrect because ST segment elevation typically indicates ongoing ischemia and damage to myocardial cells in the setting of an acute MI. Option D) MI associated with transient or incomplete coronary artery occlusion is incorrect because ST segment elevation is more indicative of a complete and prolonged occlusion leading to an MI rather than a transient or incomplete occlusion. Educationally, understanding the significance of ST segment elevation on an ECG in the context of chest pain is crucial for nurses working in cardiovascular care. This knowledge helps in prompt recognition of acute MI and initiation of appropriate interventions to minimize cardiac damage and improve patient outcomes.

Correct Answer: A

Rationale: Rationale: A) The statement that a common cause of diastolic failure is left ventricular hypertrophy is accurate. Diastolic heart failure occurs when the heart muscle becomes stiff and cannot relax properly during diastole, often due to conditions like hypertension or hypertrophy. B) While coronary artery disease (CAD) is a significant risk factor for heart failure, it is not a primary risk factor. Other common causes include hypertension, valvular heart disease, and cardiomyopathy. C) Systolic heart failure is characterized by a reduced left ventricular ejection fraction, typically below 40-50%. This means that the heart is not effectively pumping out enough blood with each contraction. D) Systolic failure is not characterized by abnormal resistance to ventricular filling. Instead, it is related to the heart's inability to contract effectively and pump blood out to the body. Educational Context: Understanding the different types and causes of heart failure is crucial for healthcare professionals working in areas like medical-surgical nursing. Recognizing the distinctions between systolic and diastolic heart failure helps in providing appropriate care and interventions for patients with heart failure. Knowledge of risk factors, diagnostic criteria, and treatment options is essential for managing heart failure effectively.