Which of the following antianginal drugs is most likely to produce tachycardia as a side effect?

Correct Answer: B

Rationale: In the context of pharmacology of cardiovascular drugs, understanding the specific mechanisms of action of each drug class is crucial to predict their potential side effects. In this case, the correct answer is B) Nifedipine, as it belongs to the dihydropyridine calcium channel blockers (CCBs) class. Nifedipine primarily acts on vascular smooth muscle to cause vasodilation, but it can also lead to reflex tachycardia due to its potent vasodilatory effects. This reflex tachycardia is a compensatory response by the body to maintain cardiac output in the face of decreased systemic vascular resistance. A) Amlodipine is also a dihydropyridine CCB like nifedipine, but it is less likely to induce reflex tachycardia compared to nifedipine due to its longer duration of action and smoother pharmacokinetic profile. C) Diltiazem and D) Verapamil are non-dihydropyridine CCBs. These drugs primarily act on the myocardium to decrease cardiac contractility and heart rate. They are more likely to cause bradycardia rather than tachycardia as a side effect. Educationally, this question highlights the importance of recognizing the different subtypes of calcium channel blockers and their specific effects on the cardiovascular system. It underscores the need for healthcare professionals to be aware of potential side effects associated with different antianginal drugs to make informed clinical decisions and provide safe and effective patient care. Understanding these nuances can help in optimizing therapy and managing adverse effects in patients with cardiovascular conditions.

Correct Answer: A

Rationale: The correct answer is option A) BP of 70/40. In this scenario, a low blood pressure (hypotension) triggers the release of renin from the kidneys. Renin is released in response to low blood pressure to kickstart the renin-angiotensin-aldosterone system (RAAS) cascade, which ultimately leads to vasoconstriction and an increase in blood pressure. Option B) BP of 145/95 is within the normal range for hypertension management with an ACE inhibitor, so it would not trigger the release of renin. Option C) Pulse of 100 and option D) Pulse of 50 are related to heart rate and not directly involved in the release of renin in response to blood pressure changes. From an educational perspective, understanding the physiological mechanisms behind drug actions is crucial in pharmacology. Knowing how medications interact with the body, including the RAAS system in this case, helps healthcare professionals make informed decisions about drug therapy and patient care. This question highlights the importance of monitoring vital signs and understanding their implications in managing cardiovascular conditions.

Correct Answer: D

Rationale: In the context of cardiovascular physiology, understanding the timing of heart sounds is crucial for accurate diagnosis. A diastolic murmur occurs during the diastolic phase of the cardiac cycle, which is the period of heart relaxation and filling. The correct answer, option D) Between the S2 and the S1 beat, is accurate because diastole is the period between the closure of the aortic and pulmonic valves (S2) and the closure of the mitral and tricuspid valves (S1). Therefore, a diastolic murmur is heard during this phase when blood flow across the atrioventricular valves produces turbulent flow. Option A) Along with the S1 beat is incorrect because S1 represents the closure of the mitral and tricuspid valves at the beginning of systole, not during diastole where a diastolic murmur occurs. Option B) Between the S1 and S2 beats is incorrect as well, as this interval corresponds to systole, when the heart is contracting and not relaxing. Option C) At the S2 beat is also incorrect because S2 represents the closure of the aortic and pulmonic valves at the end of systole, not during diastole where diastolic murmurs are typically heard. Understanding the timing of heart sounds in relation to the cardiac cycle is essential for healthcare professionals to accurately assess and diagnose cardiovascular conditions, making this knowledge crucial in the field of pharmacology and cardiology.

Correct Answer: B

Rationale: In this scenario, the most likely finding on the electrocardiogram for the 62-year-old man who took extra digoxin pills due to emotional distress would be ventricular tachycardia (Option B). Digoxin toxicity can lead to various cardiac arrhythmias, with ventricular tachycardia being a common manifestation. Acute myocardial infarction (Option A) is less likely in this case because the patient's symptoms are more suggestive of a toxic reaction to digoxin rather than a sudden blockage of a coronary artery. Pulmonary embolism (Option C) and ventricular septal defect (Option D) are also less likely as the primary cause of the presentation. Educationally, this case highlights the importance of understanding the potential arrhythmogenic effects of digoxin overdose and the need for close monitoring of patients on this medication, especially in the setting of emotional distress which may lead to non-adherence or overdose. It also underscores the significance of considering medication-related causes in patients presenting with acute cardiovascular symptoms.

Correct Answer: C

Rationale: In this scenario, the correct answer is C) Reduces intracranial pressure. Propofol is a sedative-hypnotic agent commonly used for induction and maintenance of anesthesia due to its rapid onset and short duration of action. It is known for its ability to reduce intracranial pressure, making it a valuable choice for patients undergoing neurosurgical procedures like the removal of a herniated lumbar disc. Option A) Increases blood pressure is incorrect because propofol typically causes a decrease in blood pressure due to its vasodilatory effects. Option B) Myocardial depression is incorrect as propofol has minimal negative effects on the cardiovascular system and does not typically cause myocardial depression. Option D) Significant depression of somatosensory-evoked potentials is incorrect as propofol is not known to have a significant impact on sensory-evoked potentials. Educationally, understanding the pharmacological effects of propofol is crucial for healthcare providers involved in anesthesia and sedation management. Knowing its specific actions, such as reducing intracranial pressure, can help in making informed decisions about drug selection based on the patient's condition and the surgical procedure being performed.