Overview
This lecture covers the main classes of cardiology medications, their mechanisms of action, primary uses, and common side effects, focusing on practical aspects for clinical practice.
Major Classes of Cardiology Medications
- Statins (HMG-CoA reductase inhibitors) lower cholesterol and reduce cardiovascular risk.
- ACE inhibitors (end in "-pril") reduce blood pressure and heart strain by inhibiting angiotensin-converting enzyme.
- ARBs (end in "-sartan") block angiotensin II, leading to vasodilation and lower blood pressure.
- Beta blockers (end in "-olol") decrease heart rate and contractility to lower blood pressure.
- Calcium channel blockers (most end in "-dipine") prevent calcium entry in heart/blood vessels to reduce blood pressure and heart rate.
- Diuretics remove excess fluid; thiazides end in "thiazide," loops in "amide," and potassium-sparing include spironolactone and amiloride.
- Nitrates (start with "nitro") dilate vessels for chest pain relief.
- Anticoagulants (often end with "rin") prevent blood clots.
Uses, Adverse Effects, and Considerations
- Diuretics treat edema, heart failure, fluid retention, hypertension, glaucoma, altitude sickness, renal disease, and increased intracranial pressure.
- Diuretic side effects: dizziness, lightheadedness, Na/K imbalances, orthostatic hypotension.
- Diuretic cautions: monitor for electrolyte imbalance, renal/liver dysfunction, anuria; check daily weight, I/O, electrolytes.
- Statin side effects: headache, nausea, bloating, liver dysfunction, myopathy, risk of rhabdomyolysis.
- CCBs can cause headache, dizziness, and rebound hypertension.
- ARBs risk hyperkalemia; ACE inhibitors can cause a dry cough.
- Digoxin increases cardiac output and lowers HR; watch for toxicity (nausea, confusion, visual changes).
- Warfarin and heparin are anticoagulants requiring specific lab monitoring (PT/INR, aPTT).
Key Terms & Definitions
- Statins — Lower cholesterol via HMG-CoA reductase inhibition.
- ACE inhibitors (ACEI) — Lower BP by inhibiting angiotensin-converting enzyme.
- ARBs — Block angiotensin II receptors, causing vasodilation.
- Beta blockers — Reduce HR and BP by blocking beta-adrenergic receptors.
- Calcium channel blockers (CCB) — Block calcium entry to decrease HR and BP.
- Diuretics — Increase urine output to reduce fluid overload.
- Nitrates — Dilate blood vessels for chest pain relief.
- Anticoagulants — Prevent blood clot formation.
- Orthostatic hypotension — Drop in BP upon standing, causing dizziness.
- Hyperkalemia — High potassium in blood.
- Warfarin — Oral anticoagulant, monitored by PT/INR; antidote is vitamin K.
- Heparin — Injectable anticoagulant, monitored by aPTT; antidote is protamine sulfate.
- Digoxin — Increases cardiac output, used for HF and AFib; watch for toxicity.
Action Items / Next Steps
- Review examples and suffixes/prefixes for each drug class.
- Memorize key side effects and monitoring requirements for each medication.
- Practice identifying contraindications and major cautions for common cardiology drugs.