Hypertension Flashcards
Define hypertension.
Systolic BP > 140 mmHg and/or Diastolic BP > 85 mmHg measured on 3 separate occasions in clinic
What is the NICE guidance on diagnosing HTN?
- IF measured BP >140/90 mmHg, take 2nd measurement
* IF substantially different → take 3rd measurement AND record lower of the last 2 measurements as clinic BP - IF clinic BP is between 140/90 mmHg and 180/120 mmHg, offer ambulatory blood pressure monitoring (ABPM) to confirm Dx of HTN
* Offer home BP monitoring (HBPM) to confirm Dx of HTN IF ABPM unsuitable/unable to tolerate
3. Confirm Dx of HTN in people with a clinic BP of 140/90mmHg or higher and AMPM daytime average or HBPM average of 135/85mmHg or higher.
What are the stages of hypertension?
Stage 1 Hypertension: 140/90 to 159/99 mmHg
Stage 2 Hypertension: 160/100 to 179/119 mmHg
Stage 3 Hypertension: sBP ≥ 180 mmHg or dBP ≥ 120 mmHg
Malignant HTN = BP >200/130mmHg
What is the aetiology of hypertension?
>90% primary//essential/idiopathic
10% secondary causes :
- Endocrine - diabetes, hyperthyroidism, Cushing’s, Conn’s, hyperparathyroidism, phaeochromocytoma, congenital adrenal hyperplasia, acromegaly.
- Renal - renal artery stenosis, chronic glomerulonephritis, pyelonephritis, polycystic kidney disease, renal failure.
- Cardio - coarctation of the aorta, increased intravascular volume (heart failure, liver failure, nephrotic syndrome, IV therapy/iatrogenic)
- Pregnancy - pre-eclampsia
- Drugs - sympathomimetics, corticosteroids, oral contraceptives (due to oestrogen)
What investigations should you do for HTN?
ABPM – at least 2 measurement/hour during usual waking hours
- Average of at least 14 measurements to confirm Dx of HTN
HBPM – Record BP twice daily for 4-7 days. Discard first day measurement - avg all the other measurements. 2 consecute recordings are taken at least 1min apart in morning and in evening.
Investigations for target organ damage
- Proteinuria – estimation of albumin:creatinine ratio (ACR) + test haematuria
- Glycated haemoglobin (HbA1C)
- Electrolytes
- Creatinine
- eGFR
- Total cholesterol and HDL cholesterol
- Fundi (hypertensive retinopathy)
- 12-lead ECG
Formal assessment of CVS risk using CVS risk assessment tool
What CVD risk assessment tool can be used to assess for need for primary prevention of CVD in those <85yrs?
QRISK risk assessment tool - fill out as many fields as possible. Routinely record BMI, ethnicity, FH of premature CVD, socioeconomic status. Those over 40 should have their risk estimates on an ongoing basis.
DO NOT use the tool for people with pre-existing CVD.
Prioritise people for a full formal risk assessment if their estimated 10-year risk of CVD is 10% or more.
What are the clinical features of hypertension?
Most asymptomatic (primary HTN)
If secondary, underlying cause: endocrine, renal, cardio, pregnancy.
If untreated, complications: HF, CAD, MI, CVA, stroke, peripheral vascular disease, emboli, retinopathy
Malignant HTN: visual field loss (scotoma), blurred vision, headaches, seizures, nausea, vomiting.
Signs:
- Auscultation: loud S2, S4
- Possible cause: coarctation of aorta(=radiofemoral delay); renal artery stenosis (= renal artery bruit)
- Fundoscopy to detect hypertensive retinopathy
What conservative measures can be taken to reduce hypertension?
Lifestyle interventions such as:
- reducing alcohol intake
- reducing coffee and caffeine intake
- reducing sodium intake (low sodium salt)
- stopping smoking
Things to consider: Frailty/multimorbidity – age >80
What is the medical treatment of hypertension?
Classes of medications:
- ACEi
- ARB
- CCB
- Thiazide-like diuretics
- Spironolactone low dose
- Alpha/beta-blockers
What is the first line treatment for hypertension in <55yo or diabetics?
ACEi or ARB
at When would you give a CCB as first line treatment for HTN? What is 2nd line if CCB not tolerated?
1st line: CCB
- >55yrs (no T2DM)
- African-Caribbean origin (no T2DM)
2nd line if CCB not tolerated: thiazide-diuretic
- e.g. indapamide over conventional bendroflumethiazide
NB: for HF follow NICE guidance.
What do you offer in resistant hypertension?
What must you be cautious about with this treatment?
Low-dose spironolactone (for those with a blood potassium level of 4.5 mmol/l or less).
Use particular caution in people with a reduced estimated GFR = increased risk of hyperkalaemia.
What do you offer to those with resistant hypertension and a potassium level >4.5mmol/L?
Alpha-blocker or beta-blocker
- ABs e.g. doxazosin/prazosin
- BBs e.g. atenolol, metoprolol, bisoprolol, carvedilol
Name some common side effects of alpha and beta blockers.
Beta blockers - dizziness, low HR, ED, depression (?bad dreams)
Alpha blockers - dizziness (when standing), chest pain, palpitations, rash
Name some common ACEi and CCBs and their side effects (2).
ACEi e.g. enalapril, lisinopril, ramipril –> COUGH, high potassium, high creatinine levels.
CCBs e.g. amlodipine, nifedipine, isradapine, diltiazem, verapamil –> swelling of feet and ankles, angioedema, flushing
How do you monitor HTN treatment? When should you measure sitting and standing BP?
Use CLINIC BP to monitor treatment
Sitting and standing BP required in people with:
- T2DM
- symptoms of postural hypotension
- >80yrs
When might it not be possible to monitor clinic BP?
When patients would prefer to use HBPM - provide training and advice
For patients with “white coat syndrome” or masked hypertension - use HBPM in addition to clinic BP.
…reduce BP to the following targets:
- >80yrs - clinic BP should be <150/90 and HBPM <145/85mmHg
- <80yrs - clinic BP should be <140/90 and HBPM <135/85mmHg
What are the hypertension red flags?
Stage 3 (severe) hypertension = must assess for organ damage ASAP and start drug tx immediately if target organ damage present. Repeat clinic BP in 7days if no target organ damage. AKA malignant hypertension.
REFER if:
- retinal haemorrhage/papilloedema (accelerated hypertension)
- life-threatening symptoms (new onset confusion, chest pain, signs of HF, AKI)
- suspected phaeochromocytoma (e.g. labile/postural hypotension, headache, palpitations, pallor, abdominal pain, diaphoresis)
What are the complications of hypertension?
Untreated mild to moderate - atherosclerosis in 30% and organ damage in 50% within 8-10yrs of onset
A 57-year-old man’s blood pressure is 165/105 mmHg despite standard doses of amlodipine, perindopril, doxazosin and bendroflumethiazide. Electrolytes and physical examination have been, and remain, normal. Which of the following would be your next stage in his management?
- A.Arrange for his medication to be given under direct observation
- B.Add spironolactone to his medication
- C.Arrange urinary catecholamine assays
- D.Request an adrenal CT scan
- E.Add verapamil to his medication
Poor adherence to therapy (A) is probably the most common cause of apparent resistance to hypertensive therapy.
In cases where this occurs despite good adherence, spironolactone (B) is often highly effective,
A 47-year-old woman, presents to clinic after being referred for consistently elevated blood pressure. Her last reading was 147/93. She attributes the elevated reading to stress. Her blood tests:
Sodium = 146 (135-145 mmol/L)
Potassium = 3.4 (3.5-5 mmol/L)
Random glucose= 7.7 (4.4-7.8mmol/L)
Urea = 4 (2.5-7.8 mmol/L)
The next most appropriate investigation is:
A.CT scan
B. 24-hour ambulatory blood pressure
C. Abdominal ultrasound scan
D. Aldosterone-renin ratio
E. Glucose tolerance test
The main differential= hyperaldosteronism from an adrenal tumour (Conn’s syndrome). The excess aldosterone causes hypertension, elevated sodium reabsorption and potassium excretion.
A 24-hour ambulatory blood pressure measurement (B) is the most appropriate investigation to eliminate essential hypertension.
What is the difference between primary, secondary and tertiary prevention?
Primary prevention includes health promotion e.g. promoting healthy diets in schools, fortification of cereals etc.
Secondary prevention is essentially the early detection of disease followed by appropriate intervention, such as treatment. Screening programmes fall under this category.
Tertiary prevention aims to reduce the impact of the disease and promote quality of life through active rehabilitation e.g. reducing the impact of cancer, stroke etc.
What is the target BP for a diabetic with end organ damage (e.g. nephropathy)?
130/80 mmHg
Name 5 contraindications to taking beta-blockers.
Contraindications for the use of beta blockers include:
- asthma,
- cardiogenic shock,
- marked bradycardia,
- hypotension,
- third degree AV block,
- severe peripheral arterial disease.
Uncompensated or uncontrolled heart failure is only a contraindication for the older non-selective beta blockers.
What causes cough with ramipril?
Likely involves the protussive mediators bradykinin and substance P.
Occurs in 20% of ACEi use.
What are some conservative measures for managing postural hypotension?
- Withdraw offending medication (either substitution or
discontinuation) - Rise slowly from supine to sitting to standing position
- Avoid straining, coughing, and prolonged standing in hot weather
- Cross legs while standing
- Squat, stooping forward
- Raise head of bed 10 to 20 degrees
- Small meals and coffee in the morning
- Elastic waist high stocking
- Increase salt and water intake
- Exercise, eg, swimming, recumbent biking, and rowing
Name 2 medical treatments for postural hypotension.
Fludrocortisone (1st line) - expands blood volume and reduces salt loss
Midodrine (2nd line) - last line - only for severe hypotension due to autonomic dysfunction
What are the benefits of ARB over ACEi or CCB?
No reflex tachycardia
No cough
No angio-eoedema
What are the classes of CCBs?
Dihydropyridines - nifedipine, amlodipine
- selective for vasculature
Non-dihydropyridines - verapamil, diltiazem
- negative ionotropic effect
What are the grades of hypertensive retinopathy?
0 = normal
1 = silver wiring
2 = AV nipping
3 = haemorrhages +/- exudates
4 = papilloedema
What grade of hypertensive retinopathy is this?
Grade 1 silver wiring
What is AV nipping in hypertensive retinopathy?
Narrowing of the venule as the arteriole crosses over it
Grade 2 hypertensive retinopathy
What grade of hypertensive retinopathy is this?
Grade 3 - haemorrhages shown
Cotton wool exudates may also be seen in grade 3 as shown below. These are caused by ischemia. Whereas hard exudates are more sharp and caused by lipid deposition.
What grade of hypertensive retinopathy is this?
Grade 4 papilloedema
What investigations should be done in HTN?
Urine - for proteinuria
Blood - U&Es, glucose, lipids
ECG
Other:
Renal USS
24hr ABPM
Echo
Hormone assays
CT/MRI
What are the secondary causes of hypertension in these patients?
Cushing’s
Acromegaly
Thyrotoxicosis
What is the threshold for a hypertensive emergency?
_>_200/130 mmHg with end-organ damage
Why does BP need to be lowered slowly in hypertensive emergency?
Risk of stroke e.g. if you give SL nifedipine it can trigger this
Instead use IV sodium nitroprusside
Aim to lower BP to 110mmHg over 24hrs
There is a doubling of risk of stroke for every how many mmHg in mean systolic blood pressure?
15mmHg
Can ACEi and ARBs be used in combination?
Yes
The COOPERATE study suggested to use combination in non-diabetic renal disease and HTN to decreased the progression of renal disease more than monotherapy
