12.1 Flashcards
(10 cards)
- What major systems regulate blood pressure?
Key systems include the vascular endothelium (releasing NO, prostaglandins, endothelin), the sympatho-adrenomedullary (SAM) system, and the renin-angiotensin-aldosterone system (RAAS).
- How do β-blockers lower blood pressure?
They block β-adrenergic receptors, reducing heart rate, contractility, and renin release, which decreases cardiac output and blood pressure.
- What is the mechanism of action of ACE inhibitors?
They prevent the conversion of angiotensin I to angiotensin II, leading to vasodilation, reduced aldosterone secretion, and lower blood volume.
- How do ARBs work in hypertension management?
ARBs block angiotensin II type 1 receptors, inhibiting vasoconstriction and aldosterone secretion, which lowers blood pressure.
- What’s the mechanism of action for Ca2+ channel blockers?
They inhibit L-type calcium channels in vascular smooth muscle (and in some cases, cardiac tissue), reducing vascular resistance and, for non-dihydropyridines, heart rate/contractility.
- What common side effects are associated with β-blockers?
Potential side effects include bradycardia, fatigue, cold extremities, bronchospasm (especially in asthmatics), and sexual dysfunction.
- How do the side effects of ACE inhibitors compare with those of ARBs?
ACE inhibitors often cause a dry cough, hyperkalemia, and, rarely, angioedema; ARBs are similar but usually lack the cough and have a lower risk of angioedema.
- What are typical adverse effects of Ca2+ channel blockers?
They may cause peripheral edema, headaches, flushing, dizziness, and sometimes hypotension.
- Which patient factors or contraindications affect the use of β-blockers?
β-blockers are contraindicated in patients with severe bradycardia, heart block, or asthma and may interact adversely with other cardiac conduction depressants.
- How are antihypertensive drug classes tailored to patient characteristics?
ACE inhibitors/ARBs are preferred in younger patients with high renin levels, while Ca2+ channel blockers are often chosen for older patients with low renin levels; β-blockers are indicated when comorbidities like angina or heart failure exist but avoided in asthma.
