Hypertension

Question 1

Definition

Answer 1

· Systolic > 140 mm Hg and/or diastolic > 90 mm Hg measured on three separate occasions.

· Malignant Hypertension: BP > 200/130 mm Hg

Question 2

Aetiology/Risk factors (primary)

Answer 2

o Essential or idiopathic hypertension

o Responsible for > 90% of cases

Question 3

Aetiology/Risk factors (secondary)

Answer 3

o Renal
· Renal artery stenosis
· Chronic glomerulonephritis
· Chronic pyelonephritis
· Polycystic kidney disease
· Chronic renal failure

o Endocrine
· Diabetes mellitus
· Hyperthyroidism
· Cushing's syndrome
· Conn's syndrome
· Hyperparathyroidism
· Phaeochromocytoma
· Congenital adrenal hyperplasia
· Acromegaly

o Cardiovascular
· Coarctation of the aorta
· Increased intravascular volume

o Drugs
· Sympathomimetics
· Corticosteroids
· COCP

o Pregnancy
· Pre-eclampsia

Question 4

Presenting symptoms

Answer 4

· Often ASYMPTOMATIC

· Symptoms of complications

· Symptoms of the cause

· Accelerated or Malignant Hypertension
o Scotomas (visual field loss)
o Blurred vision
o Headache
o Seizures
o Nausea and vomiting
o Acute heart failure

Question 5

Signs on physical examination

Answer 5

· Blood pressure should be measured on 2-3 different occasions before diagnosing hypertension

· The lowest reading should be recorded

· Examination may reveal information about causes:
o Radiofemoral delay = coarctation of the aorta distal to the left subclavian artery
o Renal artery bruit = renal artery stenosis
o Fundoscopy to detect hypertensive retinopathy

Question 6

Keith-Wagner classification of hypertensive retinopathy

Answer 6

i. Silver wiring
ii. As above + arteriovenous nipping
iii. As above + flame haemorrhages + cotton wood exudates
iv. As above + papilloedema

Question 7

Investigations

Answer 7

· Bloods:
o U&Es
o Glucose
o Lipids

· Urine Dipstick
o Blood and protein (e.g. if glomerulonephritis)

· ECG
o May show signs of left ventricular hypertrophy or ischaemia

· Ambulatory blood pressure monitoring
o Excludes white coat hypertension

· Other investigations may be performed if a secondary cause of the hypertension is suspected (e.g. renal angiogram)

Question 8

Management plan (non-medical)

Answer 8

· Conservative
o Stop smoking
o Lose weight
o Reduce alcohol intake
o Reduce dietary sodium

· Investigate for secondary causes (mainly in young patients)

Question 9

Management plan (general medical)

Answer 9

· Medical - treatment recommended if systolic > 160 mm Hg and/or diastolic > 100 mm Hg, or if evidence of end-organ damage. Multiple drug therapies often needed.

o ACE Inhibitors or Angiotensin Receptor Blockers - first line if:
· < 55 yrs
· Diabetic
· Heart failure
· Left ventricular dysfunction

o CCBs - first line if:
· > 55 yrs
· Black
· NOTE: thiazide diuretics can be used if CCBs are not tolerated

o Beta-Blockers
· Not preferred initial therapy
· May be considered in younger patients
· CAUTION: combining with thiazide diuretic may increase risk of developing diabetes
· May increase risk of heart failure

o Alpha-Blockers
· 4th line
· May be used in patients with prostate disease

Question 10

Management plan (target BP)

Answer 10

o Non-Diabetic: < 140/90 mm Hg

o Diabetes without proteinuria: < 130/80 mm Hg

o Diabetes WITH proteinuria: < 125/75 mm Hg

Question 11

Management plan (severe hypertension)

Answer 11

(Diastolic > 140 mm Hg)

o Atenolol
o Nifedipine

Question 12

Management plan (acute malignant hypertension)

Answer 12

o IV beta-blocker (e.g. esmolol)

o Labetolol

o Hydralazine sodium nitroprusside

o CAUTION: avoid rapid lowering of blood pressure because it can cause cerebral infarction
· This is because the autoregulatory mechanisms within the brain for regulating blood flow will cause vasoconstriction of the vessels in the brain when blood pressure is very high
· Lowering the blood pressure too rapidly would mean that the autoregulatory mechanisms do not adapt to the drop in blood pressure and so the vessels remain constricted
· A rapid drop in blood pressure with constricted vessels will cause an infarction

Question 13

Possible complications

Answer 13

· Heart failure
· Coronary artery disease
· Cerebrovascular accidents
· Peripheral vascular disease
· Emboli
· Hypertensive retinopathy
· Renal failure
· Hypertensive encephalopathy
· Posterior reversible encephalopathy syndrome (PRES)
· Malignant hypertension

Question 14

Prognosis

Answer 14

· Good prognosis if well controlled

· Uncontrolled hypertension is associated with increased mortality

· Treatment reduces incidence of renal damage, stroke and heart failure