Secondary Hypertension

Secondary Hypertension is a comprehensive clinical reference tool for healthcare professionals investigating and managing secondary causes of hypertension. Designed by a neurologist at St George's London, this app covers the full investigation pathway from when to suspect a secondary cause through to targeted management.

Secondary hypertension accounts for 5-10% of all hypertension cases and up to 20% of resistant hypertension. Early identification of a treatable secondary cause can lead to cure or marked improvement in blood pressure control.

CLINICAL CONTENT:

• When to Suspect Secondary Hypertension — Clear criteria including onset under 40, resistant hypertension, spontaneous hypokalaemia, episodic symptoms, and abdominal bruit

• Renal Parenchymal Disease — CKD, glomerulonephritis, polycystic kidney disease, reflux nephropathy, diabetic nephropathy. BP targets (NICE NG203/KDIGO 2021) and drug treatment including ACEi/ARB first-line guidance

• Renovascular Hypertension — Atherosclerotic renal artery stenosis with clinical clues, ASTRAL and CORAL trial evidence. Fibromuscular dysplasia including string of beads sign, PTA without stenting, and MRA head for aneurysm screening

• Primary Hyperaldosteronism — Screening indications, aldosterone:renin ratio methodology, drug washout requirements, confirmatory tests (IV saline infusion, fludrocortisone suppression), adrenal vein sampling, and treatment by subtype (spironolactone vs laparoscopic adrenalectomy)

• Phaeochromocytoma — Classic triad, rule of 10s, hereditary syndromes (MEN2, VHL, NF1, SDHx), plasma free metanephrines vs 24h urinary, CT HU threshold, and critical pre-operative alpha-blockade protocol. NEVER beta-blocker before alpha-blockade.

• Cushing Syndrome — Clinical features, overnight dexamethasone suppression test, 24h urinary free cortisol, late-night salivary cortisol, ACTH-dependent vs independent differentiation, inferior petrosal sinus sampling

• Thyroid and Other Endocrine — Hypothyroid (diastolic hypertension) vs hyperthyroid (systolic, wide pulse pressure), acromegaly (IGF-1 screening, OGTT with GH), primary hyperparathyroidism (bones, stones, groans, moans), parathyroidectomy

• Obstructive Sleep Apnoea — Mechanism of hypertension, STOP-BANG screening, nocturnal non-dipping pattern, polysomnography, CPAP BP reduction evidence, spironolact