Cardiovascular diseases (CVDs) remain the leading cause of death worldwide, contributing to nearly 18 million deaths annually according to the WHO. From hypertension and hyperlipidemia to arrhythmias and thrombosis, cardiac conditions demand a wide spectrum of therapeutic agents.
Cardiac pharmacology covers a variety of antihypertensives, lipid-lowering drugs, anticoagulants, thrombolytics, and antiarrhythmics, each targeting specific mechanisms to restore cardiovascular health.
Antihypertensives
Hypertension (“high blood pressure”) is a major risk factor for stroke, myocardial infarction, heart failure, and kidney disease. Several drug classes lower blood pressure by targeting different pathways.
1. ACE Inhibitors (Angiotensin-Converting Enzyme Inhibitors)
Suffix: -pril
Examples: Enalapril, Lisinopril, Ramipril
Mechanism: Inhibit ACE, preventing conversion of angiotensin I to angiotensin II (a vasoconstrictor). Reduce vasoconstriction and aldosterone secretion.
Uses: Hypertension, heart failure, diabetic nephropathy, post-MI.
Key Side Effects: Cough (due to bradykinin accumulation), hyperkalemia, angioedema.
2. Beta-Blockers
Suffix: -olol
Examples: Propranolol, Metoprolol, Atenolol
Mechanism: Block β-adrenergic receptors → decrease heart rate, contractility, and renin release.
Uses: Hypertension, angina, arrhythmias, post-MI, heart failure.
Key Side Effects: Bradycardia, fatigue, bronchospasm (non-selective β-blockers).
3. Angiotensin II Receptor Blockers (ARBs)
Suffix: -sartan
Examples: Losartan, Valsartan, Telmisartan
Mechanism: Block angiotensin II receptors → vasodilation, reduced aldosterone release.
Uses: Hypertension, heart failure, diabetic nephropathy (alternative to ACE inhibitors).
Key Side Effects: Hyperkalemia, hypotension (but no cough compared to ACE inhibitors).
4. Calcium Channel Blockers (CCBs)
Suffix: -pine (dihydropyridines), -amil (verapamil-type)
Examples: Amlodipine, Nifedipine, Verapamil
Mechanism: Inhibit calcium entry into vascular smooth muscle and myocardium.
Uses: Hypertension, angina, arrhythmias (non-dihydropyridines).
Key Side Effects: Edema, constipation (verapamil), reflex tachycardia (dihydropyridines).
5. Vasopressin Receptor Antagonists
Suffix: -vaptan
Examples: Tolvaptan, Conivaptan
Mechanism: Block vasopressin (ADH) receptors → promote water excretion without electrolyte loss.
Uses: Hyponatremia, heart failure.
Key Side Effects: Thirst, polyuria, hepatotoxicity.
6. Alpha-1 Blockers
Suffix: -osin
Examples: Prazosin, Terazosin, Doxazosin
Mechanism: Block α1-receptors → vasodilation.
Uses: Hypertension, benign prostatic hyperplasia (BPH).
Key Side Effects: Postural hypotension, dizziness.
7. Diuretics
Diuretics reduce blood pressure by decreasing blood volume.
Loop Diuretics
- Suffix: -ide / -semide
- Examples: Furosemide, Bumetanide, Torsemide
- Uses: Hypertension, edema, heart failure.
- Key Side Effects: Hypokalemia, dehydration, ototoxicity.
Thiazide Diuretics
- Suffix: -thiazide
- Examples: Hydrochlorothiazide, Chlorthalidone
- Uses: Hypertension (first-line), mild heart failure.
- Key Side Effects: Hypokalemia, hyperuricemia (gout).
- Suffix: -actone
- Examples: Spironolactone, Eplerenone
- Uses: Resistant hypertension, heart failure, hyperaldosteronism.
- Key Side Effects: Hyperkalemia, gynecomastia (spironolactone).
Antihyperlipidemics
HMG-CoA Reductase Inhibitors (Statins)
Suffix: -statin
Examples: Atorvastatin, Rosuvastatin, Simvastatin
Mechanism: Inhibit HMG-CoA reductase → ↓ cholesterol synthesis, ↑ LDL receptor expression → ↓ LDL cholesterol.
Uses: Hyperlipidemia, cardiovascular prevention (primary & secondary).
Key Side Effects: Muscle pain (myopathy), hepatotoxicity, rhabdomyolysis (rare).
Statins are cornerstone therapy for preventing atherosclerosis and coronary artery disease.
Other Cardiac Drugs
Anticoagulants
These drugs prevent clot formation and are crucial in conditions like atrial fibrillation, deep vein thrombosis (DVT), and pulmonary embolism (PE).
Factor Xa Inhibitors
- Suffix: -xaban
- Examples: Rivaroxaban, Apixaban, Edoxaban
- Mechanism: Directly inhibit factor Xa, blocking thrombin formation.
- Uses: DVT, PE, stroke prevention in atrial fibrillation.
Dicumarol-type Anticoagulants
- Suffix: -arol
- Examples: Warfarin, Acenocoumarol
- Mechanism: Inhibit vitamin K–dependent clotting factor synthesis.
- Uses: Long-term anticoagulation.
- Key Side Effects: Bleeding, requires INR monitoring.
Hirudin-type Anticoagulants
- Suffix: -irudin
- Examples: Lepirudin, Desirudin
- Mechanism: Direct thrombin inhibitors.
- Uses: Heparin-induced thrombocytopenia (HIT).
Low-Molecular-Weight Heparin (LMWH)
- Suffix: -parin
- Examples: Enoxaparin, Dalteparin
- Mechanism: Potentiate antithrombin III → inhibit factor Xa.
- Uses: DVT prophylaxis, PE, ACS.
Thrombolytics (Clot-Busters)
Suffix: -teplase / -ase
Examples: Alteplase, Tenecteplase, Streptokinase
Mechanism: Activate plasminogen → plasmin → dissolves fibrin clots.
Uses: Acute MI, ischemic stroke, massive PE.
Key Side Effects: Hemorrhage, intracranial bleeding.
Antiarrhythmics
Suffix: -arone
Examples: Amiodarone, Dronedarone
Mechanism: Prolong repolarization, block K⁺/Na⁺/Ca²⁺ channels, β-blocking effect.
Uses: Atrial fibrillation, ventricular tachycardia, supraventricular tachycardia.
Key Side Effects: Thyroid dysfunction, pulmonary fibrosis, hepatotoxicity.
Quick Reference Table
| Class | Common Suffix | Example Drugs | Primary Use |
|---|---|---|---|
| ACE inhibitors | -pril | Lisinopril, Ramipril | Hypertension, heart failure |
| Beta-blockers | -olol | Atenolol, Metoprolol | Hypertension, arrhythmias |
| ARBs | -sartan | Losartan, Valsartan | Hypertension, nephropathy |
| Calcium channel blockers | -pine / -amil | Amlodipine, Verapamil | Hypertension, angina |
| Alpha-1 blockers | -osin | Prazosin, Doxazosin | Hypertension, BPH |
| Loop diuretics | -ide / -semide | Furosemide, Torsemide | Hypertension, edema |
| Thiazide diuretics | -thiazide | Hydrochlorothiazide | Hypertension |
| K-sparing diuretics | -actone | Spironolactone | Heart failure, HTN |
| Statins | -statin | Atorvastatin | Hyperlipidemia |
| Factor Xa inhibitors | -xaban | Rivaroxaban | DVT, AF stroke prevention |
| Dicumarol type | -arol | Warfarin | Long-term anticoagulation |
| Hirudin type | -irudin | Lepirudin | HIT management |
| LMWH | -parin | Enoxaparin | Thrombosis prevention |
| Thrombolytics | -teplase / -ase | Alteplase, Tenecteplase | MI, stroke, PE |
| Antiarrhythmics | -arone | Amiodarone | Atrial fibrillation, VT |
Frequently Asked Questions (FAQs)
Q1. What is the difference between ACE inhibitors and ARBs?
Both reduce blood pressure by targeting the renin-angiotensin system. ACE inhibitors block angiotensin II formation (but may cause cough), while ARBs block its receptor (no cough).
Q2. Why are statins considered life-saving drugs?
Statins reduce LDL cholesterol, stabilize plaques, and lower cardiovascular event risk, making them vital in both prevention and treatment.
Q3. What’s the difference between anticoagulants and thrombolytics?
- Anticoagulants prevent new clot formation.
- Thrombolytics actively dissolve existing clots.
Q4. Why is amiodarone widely used despite serious side effects?
Amiodarone is highly effective against life-threatening arrhythmias, and in emergencies, its benefits outweigh long-term risks.
Q5. Which diuretic is preferred for initial hypertension treatment?
Thiazide diuretics (e.g., hydrochlorothiazide) are commonly first-line for essential hypertension.
Q6. Why do beta-blockers require caution in asthma patients?
Non-selective β-blockers (like propranolol) may cause bronchospasm, worsening asthma. Cardio-selective agents (like metoprolol) are safer alternatives.
