Hypertension and Vascular Disease
The exam tests diagnostic thresholds, secondary-cause work-up in young or resistant patients, the pharmacology of hypertensive emergencies, and the vascular diseases that present with hypertension or limb symptoms.
Diagnosis and targets
- Office threshold is 140/90 mmHg in European and Iranian practice; ambulatory 24-hour average 130/80 or more and home 135/85 or more are diagnostic.
- American guidelines use 130/80; note the discrepancy because items may quote either.
- General target is below 130/80 when tolerated, with individualisation in frail elderly patients.
Secondary causes to recognise
- Primary aldosteronism: resistant hypertension with hypokalaemia; screen with the aldosterone-to-renin ratio, confirm with saline suppression, then adrenal CT and adrenal vein sampling.
- Renovascular disease: flash pulmonary oedema, abdominal bruit, rising creatinine after ACE inhibitor.
- Pheochromocytoma: paroxysmal headache, sweating, palpitations; plasma free metanephrines first.
- Others: obstructive sleep apnoea, Cushing syndrome, thyroid disease, coarctation.
Resistant hypertension
- Defined as above target on three drugs including a diuretic at optimal dose; add spironolactone as the fourth agent.
Emergencies and vascular disease
- Hypertensive emergency means target-organ damage; use IV labetalol, nicardipine, or esmolol and lower pressure gradually except in aortic dissection.
- Aortic dissection: type A is surgical; both types need a beta-blocker first, then a vasodilator, targeting systolic 100-120 mmHg and heart rate below 60.
- PAD: ankle-brachial index 0.90 or less is abnormal; supervised exercise and cilostazol.
- AAA repair at 55 mm in men and 50 mm in women; screen men aged 65-75 with smoking history.
Worked example
A 32-year-old woman has blood pressure 170/105, potassium 3.0, and an adrenal incidentaloma. The aldosterone-to-renin ratio is high; saline suppression confirms autonomous aldosterone; CT shows a left adenoma and she undergoes adrenalectomy.
Traps
- White-coat and masked hypertension change management; confirm with ambulatory monitoring.
- Do not lower pressure abruptly in ischaemic stroke unless above 220/120.
- Bilateral renal artery stenosis can precipitate renal failure with ACE inhibitors.