[Pharma B] Anti-hypertensive & Anti-angina: Flashcards
Which calcium channel antagonists has the greatest depressant effect in the heart and may decrease HR and СО?
A. Felodipine
B. Diltiazem
C. Amlodipine
D. Verapamil
D. Verapamil
Rationale:
Calcium channel blockers (CCBs) are a class of medications that inhibit the entry of calcium ions into cardiac and vascular smooth muscle cells, leading to relaxation and vasodilation.
There are two main classes of CCBs: dihydropyridines (e.g., felodipine, amlodipine) and non-dihydropyridines (e.g., diltiazem, verapamil).
Among these, verapamil has the most pronounced effect on the heart. It not only causes vasodilation but also has a direct depressant effect on the myocardium, leading to a decrease in heart rate (HR) and cardiac output (CO).
Diltiazem also affects the heart but to a lesser extent than verapamil.
In contrast, dihydropyridines primarily act on the vascular smooth muscle and have minimal effects on the heart.
This drug is a selective funny sodium channel blocker which reduces cardiac rate by hyperpolarization-activated sodium channel in the sinoatrial node.
A. Trimetazidine
B. Ranolazine
C. Fasudil
D. Ivabradine
D. Ivabradine
Rationale:
Ivabradine is a unique anti-anginal medication that works by selectively inhibiting the “funny” (If) sodium channels in the sinoatrial (SA) node of the heart. By blocking these channels, ivabradine reduces the rate of spontaneous depolarization in the SA node, leading to a reduction in heart rate. This mechanism is different from other anti-anginal drugs and is specific to ivabradine.
These are considered first line drugs in chronic effort angina?
A. Propranolol
B. Nifedipine
C. Nitrates
D. Amlodipine
A. Propranolol
Rationale:
Propranolol is a non-selective beta-blocker. Beta-blockers like propranolol are indeed considered first-line therapy for chronic effort (or stable) angina. They work by reducing the heart rate and myocardial contractility, which in turn decreases the oxygen demand of the heart. By reducing the oxygen demand, they help alleviate the symptoms of angina that arise due to an imbalance between oxygen supply and demand in the heart.
Which of the following best describes classic/stable angina?
A. Inadequate blood flow in the presence of CAD
B. A plaque rupture leading to platelet aggregation and subendocardial ischemia at rest
C. Major coronary artery is completely obstructed by thrombus
D. Transient spasm of localized portions of blood vessels
A. Inadequate blood flow in the presence of CAD
Rationale:
Classic or stable angina is characterized by chest pain or discomfort that occurs with exertion and is relieved by rest. It is caused by inadequate blood flow to the myocardium in the presence of coronary artery disease (CAD). The other options describe different types of angina or coronary events, such as unstable angina or myocardial infarction.
Which of the following describes long term regulation of blood pressure via renal blood volume-pressure control?
A. Renin increases production of angiotensin Il
B. Both
C. Angiotensin Il causes direct constriction of resistance vessels
D. Neither
B. Both
Rationale:
The renin-angiotensin-aldosterone system (RAAS) plays a crucial role in the long-term regulation of blood pressure.
When blood pressure drops or renal blood flow decreases, the kidneys release renin.
Renin then catalyzes the conversion of angiotensinogen to angiotensin I, which is further converted to angiotensin II. Angiotensin II has multiple effects:
-It causes direct vasoconstriction of resistance vessels, increasing blood pressure.
-3It stimulates the release of aldosterone, leading to sodium and water retention, which increases blood volume and blood pressure.
Which of the following drugs are useful for pregnant women with hypertension?
A. Nitroprusside
B. Verapamil
C. Fenoldopam
D. Hydralazine
D. Hydralazine
Rationale:
Hydralazine is an arteriolar vasodilator and is one of the preferred antihypertensive agents for use during pregnancy. It is often used in combination with methyldopa for pregnant women with hypertension. The other drugs listed are not typically first choices for treating hypertension in pregnant women. Nitroprusside, for instance, can cause cyanide toxicity, and its safety in pregnancy is not well-established. Verapamil is a calcium channel blocker and is not the first choice for hypertension in pregnancy. Fenoldopam is a dopamine receptor agonist and is not commonly used in pregnancy.
The following are potassium sparing diuretics except?
A. Furosemide
B. Triamterene
C. Spinorolactone
D. Amiloride
A. Furosemide
Rationale:
Furosemide is a loop diuretic, not a potassium-sparing diuretic. It works on the thick ascending limb of the loop of Henle in the kidneys. Potassium-sparing diuretics, as the name suggests, reduce urinary excretion of potassium. Triamterene, spironolactone, and amiloride are all potassium-sparing diuretics.
Which of the following antihypertensives has no effect on bradykinin and thus has no cough as side effects?
A. Losartan
B. Amlodipine
C. Enalapril
D. Captopril
A. Losartan
Rationale:
Losartan is an angiotensin II receptor blocker (ARB). ARBs do not increase bradykinin levels, which is associated with the cough seen with ACE inhibitors like enalapril and captopril. Amlodipine is a calcium channel blocker and also does not cause cough, but among the options, Losartan is the ARB, which is specifically known for not causing the cough side effect seen with ACE inhibitors.
The following drugs are alpha adrenoreceptor antagonist except?
A. Terasozin
B. Prazosin
C. Clonidine
D. Doxasozin
C. Clonidine
Rationale:
Clonidine is an alpha-2 adrenergic agonist, not an antagonist. It acts centrally to reduce sympathetic outflow, leading to decreased blood pressure. Terazosin, prazosin, and doxazosin are all alpha-1 adrenoreceptor antagonists, which cause vasodilation and are used to treat hypertension.
The following are the vascular smooth muscle effect of nitrates except?
A. Salt and water retention is not common
B. Improved venous capacitance
C. Pulmonary vasculature and heart size are significantly reduced.
D. Decreased preload
A. Salt and water retention is not common
Rationale:
Nitrates, such as nitroglycerin, primarily cause vasodilation by releasing nitric oxide in vascular smooth muscle. This leads to improved venous capacitance (decreased venous return to the heart), reduced pulmonary vasculature and heart size, and decreased preload. However, as a compensatory mechanism in response to vasodilation and decreased blood pressure, there can be salt and water retention, which is mediated by the activation of the renin-angiotensin-aldosterone system. Thus, salt and water retention can be a side effect of nitrates.
What is the Mechanism of Action of the Drug?
Amiloride
A. Pure arterial dilator
B. Block sodium channels in the collecting tubule
C. Inhibitor of subtype 2 sodium-glucose transport protein
D. Inhibition of Na+/K+ ATPase
E. Inhibit phosphodiesterase
B. Block sodium channels in the collecting tubule
Rationale:
Amiloride is a potassium-sparing diuretic that works by blocking sodium channels in the collecting tubules of the kidneys. This action reduces sodium reabsorption and prevents potassium excretion, making it “potassium-sparing.”
ENaC Antagonist = Amiloride & Triamterene
What is the Mechanism of Action of the Drug?
Dapagliflozin
A. Pure arterial dilator
B. Block sodium channels in the collecting tubule
C. Inhibitor of subtype 2 sodium-glucose transport protein
D. Inhibition of Na+/K+ ATPase
E. Inhibit phosphodiesterase
C. Inhibitor of subtype 2 sodium-glucose transport protein
Rationale:
Dapagliflozin is a sodium-glucose co-transporter 2 (SGLT2) inhibitor. It works by inhibiting the SGLT2 protein in the proximal tubules of the kidneys, reducing glucose reabsorption and leading to increased glucose excretion in the urine. This mechanism is used to lower blood glucose levels in patients with diabetes.
What is the Mechanism of Action of the Drug?
Digitalis
A. Pure arterial dilator
B. Block sodium channels in the collecting tubule
C. Inhibitor of subtype 2 sodium-glucose transport protein
D. Inhibition of Na+/K+ ATPase
E. Inhibit phosphodiesterase
D. Inhibition of Na+/K+ ATPase
Rationale:
Digitalis (or digoxin) is a cardiac glycoside that works by inhibiting the Na+/K+ ATPase pump in cardiac cells. This action increases intracellular sodium levels, which indirectly leads to an increase in intracellular calcium levels. The increased calcium enhances cardiac contractility, making the heart pump more efficiently.
What is the Mechanism of Action of the Drug?
Aminophylline
A. Pure arterial dilator
B. Block sodium channels in the collecting tubule
C. Inhibitor of subtype 2 sodium-glucose transport protein
D. Inhibition of Na+/K+ ATPase
E. Inhibit phosphodiesterase
E. Inhibit phosphodiesterase
Rationale:
Aminophylline is a bronchodilator used to treat asthma and chronic obstructive pulmonary disease (COPD). It works by inhibiting phosphodiesterase enzymes, leading to increased levels of cyclic AMP. Elevated cyclic AMP levels cause bronchial smooth muscle relaxation, resulting in bronchodilation.
What is the Mechanism of Action of the Drug?
Hydralazine
A. Pure arterial dilator
B. Block sodium channels in the collecting tubule
C. Inhibitor of subtype 2 sodium-glucose transport protein
D. Inhibition of Na+/K+ ATPase
E. Inhibit phosphodiesterase
A. Pure arterial dilator
Rationale:
Hydralazine is an antihypertensive agent that acts as a pure arterial dilator. It relaxes the smooth muscles of the arteries, leading to vasodilation. This action reduces peripheral resistance and lowers blood pressure. The exact mechanism of how hydralazine causes arterial dilation is not fully understood, but it is known to be a direct-acting vasodilator.