Cardiovascular Drugs and Heart Function Quiz

Module 5: Cardiovascular Drugs and Diuretics

• This module covers cardiovascular drugs and diuretics, focusing on their cellular-level actions and their pharmacological basis in treating major cardiovascular diseases.
• Learning objectives include classifying major cardiovascular drugs, describing cellular actions of drugs affecting cardiovascular-renal systems, and evaluating the pharmacological basis for treatments and identifying common side effects.
• Heart failure (HF) is a complex disorder characterized by the heart's inability to pump enough blood. Symptoms include dyspnea, fatigue, and fluid retention. Left systolic dysfunction is the most common cause.
• The renin-angiotensin-aldosterone system (RAAS) plays a critical role in regulating blood volume and vascular resistance. Renin release in the kidneys is stimulated by decreased renal perfusion pressure and sympathetic stimulation. Increased renin leads to angiotensin II, a potent vasoconstrictor, and subsequent aldosterone release, leading to increases in preload and afterload.
• Cardiovascular drugs used to treat HF include inhibitors of the renin-angiotensin system (ACE inhibitors, Angiotensin II Receptor Blockers [ARBs]), beta-blockers, diuretics, and inotropic agents.
• Classification of drugs used in HF is made based on goals of pharmacologic intervention in HF (alleviating symptoms, slowing progression, and improving survival).
• Inotropic drugs enhance cardiac muscle contractility, increasing cardiac output. Digitalis glycosides (e.g., digoxin) are examples of positive inotropes.
• Positive inotropes increase calcium levels, enhancing cardiac muscle contractility. Side effects include cardiac arrhythmias, gastrointestinal distress, and central nervous system effects like headache, fatigue, and confusion.
• B-adrenergic agonists (e.g., dobutamine) can increase intracellular cyclic adenosine monophosphate (cAMP) leading to increased contractility
• Phosphodiesterase inhibitors (e.g., amrinone) increase intracellular cAMP, resulting in increased calcium concentration and greater contractility
• Some examples of diuretrics include Thiazide diuretics (for example, chlorothiazide and hydrochlorothiazide) in managing disorders involving abnormal fluid retention and hypertension, as well as Loop diuretics (for example, furosemide).
• The module examines different types of angina, including stable, unstable, and variant (Prinzmetal's) angina, addressing the mechanisms behind each type and treatment strategies.
• Antianginal drugs, like organic nitrates, β-blockers, and calcium channel blockers (CCBs), lower myocardial oxygen demand.
• Antiarrhythmic drugs regulate the electrical activity of the heart, thereby controlling cardiac rhythm, and include sodium channel blockers, β-blockers, potassium channel blockers, and calcium channel blockers. These drugs affect the rate of rise of the action potential and affect conduction velocity.