Clinicopathological Conference: Hypertension

13.11.06

Take home messages:
• HBP common and usually symptomatic.
• Vast majority of cases primary.
• Treatment to reduce stroke (and IHD) risk.
• Most pts do not take their medications.

Case
• 45-year-old man referred for investigation.
• GP has started screening programme for hypertension:
-200/100 in December;
-190/96 in January;
-190/102 in March.
• Asymptomatic.

What symptoms did you expect?
• Usually none.
• Relationship to headache dubious.
• (Causes of HBP).
• (Results of HBP).

FH
• Father died of stroke aged 55.
• Mother has had 2xMI.
• Elder brother has type II DM.

SH
• Unemployed - ex-car worker.
• Married with children at home.
• Smokes 20/day.
• Drinks 2 pints/day.
• Likes salt.
• No medications.
• NKA.

ROS: causes of HBP?
• Urinary:
-Frequent dysuria?
-Frequent renal angle pain?
-Nocturia?
-Poor stream?
• (Flushing).
• (Polydipsia).

ROS: consequences of HBP?
• Chest pain (angina).
• Dyspnoea/orthopnoea (LVF).
• Transient neurological syndromes:
-Amaurosis fugax.
-Transient hemiparesis.
-Perturbation of consciousness.

ROS: conditions relevant to drugs
• Airways obstruction: β blockers.
• Local urinary problems (prostate in men, stress incontinence in women): loop diuretics.

Examination?
• BP today.
• Consequences of hypertension.
• Other causes of atheroma.
• Causes of hypertension.
• BP = 190/100.

Consequences
• Apex beat - thrusting, but not displaced.
• Heart sounds.
• Fundi.
• (Signs of heart failure).

Other causes of atheroma
• Hyperproteinaemias:
-Xanthomata.
-Xanthalesmata.
-Corneal arcus.

Causes
• Endocrine:
-Phaeochromocytoma.
-Cushings - buffalo hump on back of next with acne and lanego - obesity - peripheral wasting - striae.
-Acromegaly - growth hormone-secreting tumour of anterior pituitary - large tongue, protruding jaw, gappy teeth.
-Conn's - hypokalaemia.
• Metabolic:
-Hypercalcaemia - no physical signs.
• Vascular:
-Coarctation of aorta.
-Renal artery stenosis.
• Renal:
-Polycystic kidneys.
-Features of chronic renal failure.
-Features of nephritic syndrome - vast quantities of albumin in urine - oedema - hypoalbuminaemia.

Case
• Nil on ROS.
• Nil O/E (save wheezy chest).

What tests do you want?
• Urinary.
• Blood.
• Imaging.
• "Special" [har har.]

Urine tests
• Dipstick urinalysis:
-Blood and protein: could be clue to renal pathology.
-Sugar: may be clue to DM.
• MSSU (mid-stream specimen of urine):
-Look for white cells as well as organism growth.
• ALL NORMAL.

Blood tests
• Assess renal function: urea and creatinine.
• (Assess calcium).
• (Assess potassium).
• Fasting blood sugar.
• Fasting lipids - cholesterol = 7.2mmol/L.

Imaging: what do you want to know?
• CXR may help decide about cardiomegaly (but many radiologists think this unnecessary).
• CXR will allow assessment of COAD, and will exclude unsuspected cancer.
• (CXR may pick up Coarctation).
• Renal USS:
-Helps exclude polycystic disease, RAS and hydronephrosis.
-But unless biochemistry abnormal, renal USS often not needed.
• R = 13cm, L = 9cm; ?RAS; what next?

Renal isotope scan with captopril challenge
• Isotope injected IV and excreted.
• Scanning allows rate and extent of excretion of isotope to be determined for each kidney.
• Captopril would reduce perfusion in kidney with RAS.

Lifestyle
• Stop smoking.
• Reduce saturated fat, alcohol, salt.
• Increase oily fish and vegetables.
• Exercise.

Shall we start treatment?
• Trying to decide that patient has SUSTAINED HBP.
• At least 3 recordings, several weeks apart.
• Augmented by 24-hr BP monitor.

Choice of drug
• Little evidence if differences in efficacy.
• Patient needs to understand aims of treatment, and risks.
• Aim for as few drugs as possible, at as low a dose as possible.

Thiazides
• Eg. bendrofluazide.
• Inexpensive, effective.
• Increase HDL cholesterol and sugar.
• May precipitate gout.
• May cause impotence.

ACE-inhibitors
• Eg. captopril, enalapril, ramipril, lisinopril.
• Effective, but more expensive.
• Well tolerated.
• Contraindicated in presence of bilateral RAS (rapid worsening of renal function).

Calcium-channel antagonist
• Eg. nifedipine, verapamil, nicardipine, diltiazem.
• Effective, more expensive than thiazides.
• Lots of symptomatic toxicity:
-Constipation.
-Flushing.
-Ankle swelling.
-(Gum hypertrophy) - nifedipine.

β-blocker
• Eg. atenolol.
• Effective and inexpensive.
• Contraindicated in:
-Airways obstruction.
-PVD.
-Bradyarrhythmias eg. heart block.
-(Heart failure).
• Symptomatic adverse effects - tiredness, cold extremities.

Case
• BP remained high on 2 further outpatient visits.
• Cholesterol was unaffected by diet.
• Treated with enalapril and simvastatin September 1998.

Follow-up
• October 1998: still no lifestyle change. BP = 180/106.
• February 1999: cholesterol now 5.0. Enalapril dose now maximal. BP = 170/100.
• April 1999: BP = 160/96. Add thiazide.
• June 1999: BP = 140/92. Cholesterol 6.2. Simvastatin dose increased.

Emergency admission July 1999
• 2/24 of tight Retrosternal chest pain associated with:
-Sweating.
-Dyspnoea.
-Nausea.
• Pale, BO = 110/50. Fine basal crackles.

Tests and management
• ECG looking for ST segment changes.
• Trop-T.
• CXR.
• Diamorphine (with anti-emetic).
• FOLLOW PROTOCOL for streptokinase.
• Monitor.
• Aspirin.

Further follow-up
• September 1999: no change in lifestyle. BP = 160/94, cholesterol 5.5.
• November 1999: 2 episodes sudden loss vision in left eye. Carotid bruit noted.
• Diagnosis and investigations?

Tests
• Carotid Doppler studies: 80% occlusion of left carotid artery.
• Referred for vascular surgery opinion.
• Continued on aspirin.

Emergency admission 01.01.01
• Sudden onset right hemiparesis.
• Severe dysphasia.
• Unsafe swallowing.
• Deterioration to GCS 7/15.
• CT shows large haematoma on left.
• Cardiac arrest.