Hypertension Flashcards
What is secondary hypertension due to?
Renal disease Renovascular disease Conn's syndrome Cushing's syndrome Hyperthyroidism Phaeochromocytoma (tumour of adrenal gland releasing adrenaline) Pregnancy Drugs (NSAIDs, corticosteroids, venlafaxine, ciclosporin, sympathomimetics)
What are the NICE treatment targets?
SBP <140mmHg
DBP <90mmHg (<80mmHg in diabetes)
What are specific goals in treating hypertension?
Reduction in cardiovascular damage
Preservation of renal function
Limitation or reversal of left ventricular hypertrophy
Prevention of IHD
Reduction in mortality due to stroke and MIs
What are common ACEIs?
Captopril Enalapril Lisinopril Perindopril Ramipril
What do ACEIs do?
Reductions in angiotensin II
reductions in arterial and venous vasoconstriction
Reduced aldosterone production leading to reductions in salt and water retention
Potentiate bradykinin (cough)
Prevention of nephropathy in DM
What are the side effects of ACEIs?
May increase potassium- interaction with salt (KCL) substitute
Angioedema
Worsening renal function
When should ACEIs be avoided?
Renovascular disease
Renin-dependent hypertension, ACEIs lead to renal undwrperfusion and severe hypotension
What are AT1 receptor antagonists (ATRAs/ARBs)?
Candesartan, losartan, valsartan
Block the action of AII at the AT1 receptor
These agents have similar consequences as ACEIs but don’t give rise to a cough
What are common calcium channel blockers?
Dilitiazem
Verapamil
Dihydropyridines (amlodipine, felodipine, nifedipine)
What do calcium channel blockers do?
Vasodilators
Inhibit voltage operated calcium channels on vascular smooth muscle, leading to vasodilation and a reduction in BP
How does verapamil differ from the dihydropyridines?
Verapamil exerts most of its effects on the heart compared with dihyropyridine which has a greater effect on arteriole smooth muscle
What are alpha-blockers?
Doxazosin, prazosin
These are competitive receptor antagonists of a1 adrenoceptors
Last choice antihypertensives
Wide spread side effects makes them poorly tolerated
What are adverse effects of calcium channel blockers?
Peripheral oedema
Postural hypotension
Constipation
What are the adverse effects of thiazides?
Urination Diabetogenic Alter lipid profile Hypokalaemia Impotence Postural hypotension
What are the adverse effects of beta blockers?
Bronchospasm
Reduce hypoglycaemic awareness
What are the adverse effects of alpha-blockers?
Widespread
Postural hypotension
What lifestyle changes should occur to try and treat hypertension?
Alcohol consumption should be reduced Weight reduction Reduce excess caffeine Reducing fat and salt intake Increasing fruit and oily fish in the diet Increasing exercise Smoking cessation
How should hypertension be confirmed by further measurements?
Ambulatory- 14 measurements
Home devices
Both arms
What are the stages of hypertension?
Stage 1: >140/>90
Stage 2: >160/>100
Stage 3: >180/>110
Who should be treated with antihypertensive drugs?
Stage 1 with 1 or more of: end organ damage, diabetes, CV disease< high CV risk
All patients with stage 2
What are the rules for use of antihypertensives in certain conditions?
Choose B-blockers in IHD Avoid B-blockers in asthma Choose ACEI in diabetic neuropathy Choose ACEI in CHF Avoid ACEI in renovascular disease Avoid thiazides in gout
When should you use ACEis (or AT1 receptor antagonists)?
Heart failure
Left ventricular hypertrophy
Diabetic neuropathy
When should you use calcium channel blockers?
Afro-caribbean ethnicity
DHPs in isolated systolic HT
Dilitiazem/verapamil in angina but not CHF
When should you use thiazides?
Elderly
When should you use beta-blockers?
MI
IHD
CHF
When should you use alpha blockers?
Resistance to other drugs
Prostatic hypertrophy
What is the flow chart for prescribing antihypertensives?
Young (<55) and non-black, high renin- A Older (>55) black, low renin- A Step 2- A+C Step 3- A+C+D Step 4 (resistance): add alpha blocker, spironolactone, other diuretic, other beta-blocker
What has the ALLHAT trial shown>
Thiazides are viewed as first line drugs, even for patients with diabetes
When should statins be considered?
For all patients with high risk for CV disease, irrespective of cholesterol level
How is Conn’s syndrome diagnosed via a blood test?
Evidence of Na retention or K loss
How is Addison’s disease diagnosed via a blood test?
Evidence of Na loss or K retention
Associated with hypotension
Why is an ECG sometimes required?
Identify left ventricular hypertrophy
What are common side effects of calcium channel blockers?
Headache
Ankle swelling due to arteriolar vasodilatation
What are most effective at lowering triglycerides?
Fibrates
What is simvastatin?
Used in hypercholesterolaemia
HMG CoA reductase inhibitor
Should be taken at night, when cholesterol synthesis is greatest
What are the side effects of simvastatin>
Headaches
Nausea
GI upset
Muscle myopathy (rare)
