Hypertension and Vascular Disorders
Core concepts
Know primary vs secondary hypertension: young onset, resistant hypertension, hypokalemia (hyperaldosteronism), episodic headache/sweating (pheochromocytoma), renal bruit (renal artery stenosis), and cushingoid features. Malignant hypertension causes TMA, papilledema, and end-organ damage; treat with controlled reduction, not rapid normalization.
Renal artery stenosis: atherosclerotic (older, diffuse atherosclerosis) vs fibromuscular dysplasia (young women, "string of beads"). ACE inhibitor can precipitate AKI in bilateral disease. Renovascular hypertension may need revascularization in selected cases.
Pheochromocytoma: plasma free metanephrines; alpha-blockade before beta-blockade. Primary aldosteronism: aldosterone-to-renin ratio; confirm and lateralize. Resistant hypertension: confirm adherence, screen for secondary causes, add spironolactone.
Traps
Do not normalize BP abruptly in malignant hypertension-risk of stroke and blindness. Beta-blocker before alpha-blocker in pheochromocytoma causes unopposed alpha vasoconstriction. Fibromuscular dysplasia is not atherosclerotic and often responds to angioplasty.
Rule of thumb
Resistant hypertension = three drugs including a diuretic at optimal doses, or controlled on four; screen for aldosteronism and adherence.
Worked example
A 32-year-old woman with BP 180/110 and no hypokalemia has a renal bruit; imaging shows beaded renal arteries. Diagnosis: fibromuscular dysplasia; consider angioplasty.