CVS - Hypertension Flashcards
Diagnostic classification of clinic blood pressure levels
Optimal <120/80 Normal 120-129/80-84 High-Normal 130-139/85-89 Mild HTN 140-159/90-99 Moderate HTN 160-179/100-109 Severe HTN >/180/110 Isolated systolic HTN >140/<90
What patients are eligible for absolute CVD risk assessment
Adults >/ 45yoa or >35 in ATSI
No known history of CVD
Those with persistently elected BP >/180/110 or with target organ damage already have high absolute CVD
The risk assessment algorithm and treatment options are not appropriate for people with known CVD
- established vascular disease
- prior MI
- prior stroke or TIA
- PAD
- end stage kidney disease
- heart failure
- AF
- aortic disease
What patients are ineligible for absolute CVD risk assessment
Adults <45yoa or <35 yoa in ATSI without known CVD (prior MI, prior stroke/TIA, peripheral artery disease, heart failure, AF, aortic disease, or end-stage kidney disease undergoing dialysis)
What patients are already high risk (>15% chance of a cardiovascular event in the next 5 years)
Diabetics >60yoa or with microalbuminuria (urine albumin:creatinine 2.5-25mg/mmol Males, 3.5-35mg/mol Females)
Moderate or severe CKD with macroalbuminuria (urine albumin:creatinine >25 Mmg/mmol Males, >35 mg/mmol Females) or EGFR <45
Familial hypercholesterolaemia
Systolic BP >/180 OR diastolic bP >/110
Total cholesterol >7.5
ATSI >74
Hypertensive urgencies
Are severe BP elevations >180/110 that are not immediately life threatening, but are associated with symptoms (severe headache) or moderate target organ damage
Treat with oral drugs and follow up within 24-72 hours
Hypertensive emergencies
When BP is very high >220/140 and acute target organ damage or dysfunction is present (heart failure, acute pulmonary oedema, acute MI, aortic aneurysm, acute renal failure, major neurological changes, hypertensive encephalopathy, papilloedema, cerebral infarction, hemorrhagic stroke)
Hospitalise with close BP monitoring and parenteral antihypertensives
Accelerated hypertension
Severe hypertension with the presence of retinal haemorrhages and exudates
Malignant hypertension
Severe hypertensions with retinal haemorrhages and exudates plus papilloedema
How to measure BP in clinic
With either a mercury sphygmomanometer or an automated digital device
Cuff with bladder length of >/80% and width >/40% of mid-upper arm circumference.
Palpate pulse prior to measuring BP and if irregular pulse then measure BP manually over the brachial artery
Quiet room
Appropriate temperature
Patient seated (legs not crossed) and relaxed for several minutes before measurements
Patient free of caffeine and smoking for at least 2 hours
Selected arm free from constricted clothing, wrap cuff snugly and place cuff at heart level by supporting the arm
Start the first measurement after 5 minutes of rest
Take 3 readings, at 1-2 minute intervals and average the last 2 readings. If the readings vary more than 10mmHg systolic or 6mmHg diastolic, have the patient rest quietly for 5 minutes and then re-measure
For first BP, measure both arms and if variation of >5mmHg use the higher reading arm for all subsequent measures
Where there is suspected postural HTN do both sitting and standing BP after 2 minutes
HTN diagnosis on clinic BPM
Should be based on multiple measurements, taken on several separate occasions. That is at least twice, one or more weeks apart, or sooner if HTN is severe
Clinical indications for out-of-clinic BPM
Suspicion of which-coat HTN
Suspicion of masked HTN
Identification of white-coat HTN
Marked variability of clinic and home BPM
Autonomic, postural, post-prandial and drug-induced hypotension
Identification of true resistant HTN
Suspicion of nocturnal HTN or absence of nocturnal dipping (e.g. sleep apnoea, CKD or diabetes)
Criteria for the diagnosis of HTN using different methods of BP measurements
Clinic >/140 systolic and/or >/90 diastolic
ABPM daytime >/135 systolic and/or >/85 diastolic
ABPM night >/120 systolic and/or >/70 diastolic
ABPM over 24hrs >/130 systolic and/or >/80 diastolic
HBPM >/135 systolic and/or >85 diastolic
Medical history to take
BLOOD PRESSURE
New onset HTN
Duration of raised BP and previous levels
ABPM and HBPM if known
Current antihypertensives
Previous antihypertensives, efficacy and adverse effects
Medications that influence BP
RISK FACTORS
Family and personal history of CKD, HTN, diabetes, dyslipidaemia, stroke, early onset coronary artery disease (before 55 in men and 65 in women), low birth weight
Modifiable lifestyle factors including smoking, diet, weight control, obesity, exercise, recreational drug use, alcohol intake
Personal, psychosocial and environmental factors including education, family situation, work environment, financial concerns, psychological stress
Depression, social isolation, quality of social support
END ORGAN DAMAGE
Past of current symptoms of IHD, heart failure, cerebrovascular disease or peripheral arterial disease
Past or current symptoms that suggest CKD
SECONDARY HTN
Phaeochromocytoma (headaches, sweating, palpitations)
Sleep apnoea (obesity, snoring, daytime sleepiness)
Complementary or recreational drug use
Hypokalaemia (muscle weakness, hypotonia, muscle tetany, cramps, cardiac arrhythmias)
Thyroid disease
Substances that may influence BP
NSAIDS Sympathomimetics (decongestants, diet pills, cocaine) Stimulants (AHDHD meds) Excessive alcohol intake Oral oestrogen contraceptives HRR Corticosteroids Clozapine SNRIs MAOis Haemopoietic drugs Withdrawal of bromocriptine, clonidine Bupropion
Bitter orange, ginseng, guarana Caffiene pills Natural liquorice St John's wort Energy drinks
Recommendations on methods of BP measurement
If clinic BP is >/140/90, or HTN is suspected, ABPM or HBPM should be offered to confirm the BP level
Clinic BP measures are used in absolute CVD risk calculators NOT home/ambulator BPs
Procedures for home BPM or ABPM should be adequately explained to patients
Finger/wrist BP measuring devices are not recommended
When reviewing ABPM data
2 measurements per hour when waking and >/14 measurements
Compare the profile with standard values
The normal range differs to clinic BP
HTN diagnosis is supported if a patient’s average ABPM reading exceeds standard values for daytime OR nighttime, or if ambulatory BP load is reported and exceeds the reference range by 20%
Mean night time systolic ABPM should be 10% lower than the daytime level. Those who are non dippers are at increased CVD risk
Physical Examination for HTN
SIGNS OF SECONDARY HTN or ORGAN DAMAGE
Pulse rate, rhythm, and character
JVP
Evidence of cardiac enlargement (displaced apex, extra heart sounds)
Evidence of cardiac failure (basal crackles, peripheral oedema, pulsatile liver)
Evidence of arterial disease (carotid, renal, abdominal or femoral bruits; AAA; absent femoral pulses, R-F delay)
Palpation of enlarged kidneys
Abnormal of the optic funds (retinal haemorrhages, papilloedema, tortuosity, thickening of AV nipping of retinal arteries, exudates or diabetic retinopathy)
Evidence of abnormality of the endocrine system (Cushing’s, thyroid)
EVIDENCE OF OBESITY
Waist circumference
BMI
Initial laboratory investigations for ALL patients
Urine dipstick for blood - if abnormal send for microscopy
Albuminuria and proteinuria status
- Mandatory for diabetes, highly recommended in all
- Urine albumin:creatinine in first void (or spot is also acceptable)
- If in macroalbuminuria range, then a 24 hour protein level
- If proteinuria then urine PCR can be used for quantification and monitoring
Bloods
- fasting glucose
- fasting serum total cholesterol, LDL, HDL and TG
- serum urea, electrolytes and creatinine (with eGFR)
Hb
12 lead ECG
- to detect AF, LVH and evidence of previous ischaemic heart disease
What is microalbuminuria on tests
ACR mg/mmol Males 2.5-25; Females 3.5-35 Albumin excretion mg/day 30-300 PCR mg/mmol Males 4-40, Females 6-60 Protein excretion mg/day 50-500 Protein reagent strip trace to +1
What is macroalbuminuria on tests
ACR mg/mmol Males >25; Females >35 Albumin excretion mg/day >300 PCR mg/mmol Males >40, Females >60 Protein excretion mg/day >500 Protein reagent strip >/ +1
What additional tests are required for patients with cardiovascular disease
Echocardiography - To diagnose LVH
Carotid USS - To rule out asymptomatic atherosclerosis
What additional tests are required for patients with chronic kidney disease
Renal artery imaging
Renal artery duplex USS, renal nuc med and/or CT angiogram
What additional tests are required for patients with peripheral arterial disease
Ankle-Brachial index (ABI) in those with risk factors for PAD including hypertensive patients with:
- diabetes
- vascular bruit
- old age
- smokers
An index <0.9 is diagnostic for PAD
Other additional tests that may be required
Plasma aldosterone/renin ratio to rule in/out primary aldosteronism
This occurs in 5-10% of patients with HTN and is not excluded by a normal serum potassium
Consider in patients with HTN, moderate-severe, or treatment resistant HTN, and those with hypokalaemia
Metanephrine and normetanephrine excretion (with creatinine) and/or plasma catecholamine, metanephrine and normetanephrine concentration, 24 hour urinary catecholamine - IF symptoms of episodic catecholamine excess and/or episodic HTN suggestive of phaeochromocytoma
Recommendations for lifestyle advice
PHYSICAL ACTIVITY
150-300 minutes of moderate intensity
OR 75-150 minutes of vigour activity each week
For >65 yoa aim to accumulate at least 30 minutes of moderate-intensity activity preferably all days
Start low and go slow as sudden vigorous activity has been associated with increased risk of cardiovascular events
Patients with chronic disease can be referred to an exercise physiologist or physiotherapist
Muscle strengthening activities on at least 2 days of each week
WEIGHT CONTROL
Waist circles <94 in males or <90 in Asian males
<80 in females
BMI<25
1kg weight reduction = ~1mmHg diastolic BP lowering
DIET
Total fat account for 20-35% of energy intake
Salt to 6g/day for primary prevention and 4g/day for secondary prevention
Choose labeled foods with <400mg/100g of salt. LOW SALT foods are those with less than 120mg/100g of salt
5 serves of veg and 2 serves of fruit/day
Can use the DASH diet - Dietary Approaches to Stop Hypertension
SMOKING
Cease
ALCOHOL
No more than 2 standard drinks on any one day
No more than 4 on any occasion
No more than 10/week
Which patients will require medical review prior to physical activity and supervised physical activity
Unstable angina BP >/180 systolic OR >/110 diastolic Uncontrolled HF or cardiomyopathy MI within the last 3 months Severe aortic stenosis Resting tachycardia or arrythmias Chest discomfort or SOB at rest of low activity Diabetes with poor glycaemic control
BMI classifications
18.5-24.9 Healthy 25 - 29.9 Overweight 30 - 34.9 Obesity I 35 - 39.9 Obesity II 40 + Obesity III
When to initiate antihypertensives
Consider a patient’s absolute CVD risk with accurate BP readings
those with mild HTN who are stratified as moderate to high absolute CVD risk
those with low absolute CV risk, but persistent BP >/16-/100 should be commenced
Patients with uncomplicated HTN should be targeted to treat to <140/90 or lower if tolerated
In selected high CV risk populations aim for target of <120 systolic BP and monitor for hypotension, syncope, electrolyte abnormalities and acute kidney injury
Choice of antihypertensive drug
In patients with uncomplicated HTN can use either ACE I, ARB, Ca C blockers or a thiazide diuretic as either monotherapy or combination therapy unless contraindicated
MOA ACE inhibitors
Reduces the synthesis of angiotensin-2 by inhibiting the action of ACE
Can precent the onset of nephropathy and reduced mortality in early diabetes. Are more effective in preventing coronary heart disease with patients with HTN
MOA ARBs
Bind directly to the angiogenesis 1 reception, preventing its activation by angiotensin 2
Can better prevent kidney failure in people with advanced diabetic nephropthy
Superior combination therapy
ACE inhibitor and Calcium channel blockers superior
Then ACE inhibitors and diuretics
Then beta blockers and diuretics
Drug treatment strategy to reach BP target
Lifestyle advice for everyone
Manage associated conditions for everyone
Start a low-moderate recommended dose of a first line drug, if not tolerated change to a different class and start again at a low-moderate dose
IF TARGET NOT REACHED AFTER 3 MONTHS Add a second drug from a different class at a low-moderate dose
IF TARGET NOT REACHED AFTER 3 MONTHS
Increase the dose of 1 drug (excluding thiazides) incrementally to the maximum recommended dose
IF TARGET NOT REACHED AFTER 3 MONTHS Despite maximal doses of at least 2 drugs, a third drug class can be started at a low-moderate dose
IF BP REMAINS ELEVATED
Consider seeking specialist advice
ACE/ARB plus calcium channel blocker
Effective combination
Useful in presence of diabetes and/or lipid abnormalities
ACE/ARB plus thiazide diuretic
Effective combination
Useful in presence of heart failure or post stroke
