Hypertension, Heart Failure and Cardiac Arrhythmias Flashcards
what is hypertension
raised blood pressure
Systolic >140mm Hg
( > 160mm Hg in isolated systolic hypertension )
Diastolic > 90mm Hg
- Normal BP is 120/80
3 separate resting measurement and average
normal BP
120/80
is blood pressure constant
not a constant,
varies from person to person,
defined parameters where you would like the patient to lie
8 risk factors for hypertension
age
race
obesity
alcohol
family history
pregnancy
stress
drugs
how is age a risk factor for hypertension
Tends to rise with age as blood vessels get less elastic
Pulse pressure becomes higher, so systolic pressure rises (diastolic a little)
Age alone should not put you at risk – combination of factors
Risk factors change throughout life too
4 drugs that can increase risk of hypertension
Non steroidal
Corticosteroids
Oral contraceptives
Sympathomimetics
2 outcomes of hypertension
accelerated atherosclerosis
- can lead to Myocardial Infarction; Stroke; Peripheral Vascular disease
renal failure
risk of CV problems is proportional to BP
- treatment of HBP can reduce risk (except for coronary heart disease; atherosclerosis stays after treatment)
3 main influences on hypertension
environment
(inactivity, stress, obesity, tobacco, age, salt, alcohol)
gene/environment interactions
genes
common triggers for hypertension
none
this is essential hypertension
- can’t find source
essential hypertension
no triggers found
common
2 rare triggers for hypertension
renal artery stenosis
endocrine tumours
renal artery stenosis and how that can cause hypertension
Kidney helps alter BP
Kidney is maldiffused due to blockage (damaged vessels – narrow, weaken or harden)
- Thinks BP has dropped due to HBP lowering flow through in kidney, so then tries to retain salt and water = worsen HBP = worse kidney problems
Renal arteries of aorta at right angles – common area for atherosclerosis – can cause narrowing of artery so less blood flow in
can be congenital issue
3 endocrine tumours that can cause hypertension
Phaeochromocytoma (Adrenaline)
- Tumour of adrenal gland
- Adrenal gland sits on top of kidney
Crohn’s Syndrome (aldosterone)
Cushing’s Syndrome (cortisol)
- Tumour causing excess cortisol – so retaining too much salt and water
signs and symptoms of hypertension
Usually NONE
May get headache
- More common in ‘malignant hypertension’
May get Transient Ischaemic Attacks
- TIA’s are ‘mini strokes’ due to atherosclerosis caused by HBP – can be warning of HBP
Full neurological return in 24hrs
4 indications for further investigation
young patient
resistant hypertension
accelerated hypertension
‘unusual history’
5 investigations for hypertension
Urinalysis
- Biochemistry can be upset due to changes in absorption
Serum Biochemistry
- (electrolytes, urea & creatinine)
Serum Lipids
ECG
- occasionally
renal ultrasound, renal angiography, hormone estimations
- (need indication to do them)
aim of treatment for hypertension
BP < 120/90 mm Hg (aim for 140/90 otherwise no benefit of medicine)
treatments for hypertension
Modify risk factors
Single daily drug dose (higher compliance)
- thiazide diuretic
- beta blocker ; lower heart rate and cardiac output but may not help vasoconstrictors – poor evidence but still use
- Calcium Channel antagonist
- ACE inhibitor
4 single daily drugs used to treat hypertension
- thiazide diuretic
- beta blocker ; lower heart rate and cardiac output but may not help vasoconstrictors – poor evidence but still use
- Calcium Channel antagonist
- ACE inhibitor
side effect of thiazide diuretic
gout
side effect of beta blocker
COPD and asthma
side effect of ACE inhibitor
PVD
what drugs should be used in younger hypertension patients
Lower risk with beta blocker and ACE inhibitor for younger
what drugs should be used in older hypertension patients
thiazide diuretic and calcium channel blockers (less chance of being affected by long term side effects)
what is heart failure
ability of heart to make a CO necessary for its function is compromised
- cannot meet oxygen demands of tissues
imbalance between body needs and ability of heart to delliver
2 types of heart failure
high output failure
low output failure
2 causes of high output heart failure
anaemia
- less RBC, can no longer HR to meet oxygen demand
thyrotoxicosis
what type of heart failure is commonest
low output failure
body’s demand is roughly the same but unable to pump as effectively
causes of low output heart failure
cardiac defect e.g. MI, valve disease
left heart failure
More chance of failure due to increase pressure and workload
right heart failure
can happen in isolation (MI or issue with lungs meaning harder to pump)
congestive heart failure
high pressure in lungs knock on left side as more to pump which then means right has to work more to pump into the lungs
- both sides effected
does left or right heart failure happen in isolation usually
no
how can ventricle failure lead to heart disease
failure of ventricle, CO fall, BP fall, increase in blood vessel constriction, increase aldosterone – inc in BP and inc in constriction,
reduce CO causing circle to go round again as lower BP
cycle gets worse and worse and worse – repeated cycles lead to heart failure
brain assumes loss of BP is haemorrhage – increase fluid levels and platelets in body but pump failure is the issue – builds up pressure – leads to pulmonary oedema and oedema swelling
what is a simplified way to explain the commonest cause of heart failure
pump stops pumping around system – commonest issue
- certain areas easier to deliver oxygen over others
aetiology of low output failure (5)
Heart Muscle disease
- MI, Myocarditis
- (diabetes, obesity)
Pressure Overload
- Hypertension – more through = more likely to fail
- aortic stenosis
Volume Overload
- mitral incompetence
- Aortic incompetence
Arrythmias
- Atrial fibrillation
- Heart Block
Drugs
- beta blockers - used to manage heart attacks, less likely to have arrhythmia (combine with cardiac muscle issue leads to heart failure)
- corticosteroids
- anticancer drugs
heart muscle diseases lead to low output failure
MI, mycarditis
diabetes, obesity
how does pressure overload lead to low output failure
Hypertension – more through = more likely to fail
aortic stenosis
how does volume overload lead to low output failure
mitral incompetence
Aortic incompetence
how does arrhythmia lead to low output failure
- Atrial fibrillation
- Heart Block
what 3 drugs can lead to low output failure
beta blockers
corticosteroids
anticancer drugs
how can beta blockers lead to low output failure
sed to manage heart attacks,
less likely to have arrhythmia (combine with cardiac muscle issue leads to heart failure)
flagpost symptoms of heart failure
shortness of breath
swelling of feet and legs
chronic lack of energy
difficulty sleeping at night due to breathing problems
swollen or tender abdomen with loss of appetite (ascites)
- due to right side failure and venous pooling
cough with frothy sputum
increased urination at night
confusion and/or impaired memory
how can heart failure cause difficulty sleeping at night
breathing problems
usually sleep propped up – lie down get breathless (left failure causing pulmonary oedema
how do the symptoms and signs of heart failure change
depend upon ‘side’ mainly affected
left heart failure symptoms and signs
dyspnoea,
tachycardia,
low BP,
low vol. Pulse,
pulmonary oedmea
(venous pressure building up on left side - lungs & systolic effects, fluid in lungs)
right heart failure symptoms and signs
swollen ankles (both affected) - pitting oedema
ascites,
raised JVP,
tender enlarged liver,
poor GI absorption
(venous pressure elevated)
ascites
abnormal buildup of fluid in the abdomen
swollen or tender abdomen with loss of appetite
- due to right side failure and venous pooling
JVP
vertical distance between the highest point at which pulsation of the jugular vein can be seen and the sternal angle.
what can impact the signs and symptoms of heart failure
how the patient is positioned
acute treatment of heart failure
emergency hospital management
Oxygen, morphine, frusemide (diuretic)
chronic treatment of heart failure
community based (most of the time)
- improve myocardial function
- reduce ‘compensation’ effects
- where possible treat the cause
appearance acute heart failure on an X-ray
white area is fluid - larger than in health (less air in lungs)
Heart width bigger – muscle problem, more flabby, poor contraction
4 underlying causes of heart failure you may treat
hypertension
valve disease
heart arrhythmias (atrial fibrillation)
thyroid disease
4 drug therapies for chronic heart failure
Diuretics - increase salt and water loss
ACE inhibitor - reduce salt/water retention, and reduce some compensation (hypertension)
Nitrates - reduce venous filling pressure
Inotropes - digoxin
- work to make the heart more efficient
- STOP negative inotropes - beta blockers! (make it worse)
tachy arrhythmias are
FAST
commonest, 160-170 not 60-70,
- can only move blood into coronary arteries during diastole so issue as increase HR the amount of diastole time shortens – reduces coronary artery flow, more likely to have MI
2 types of tachy arrhythmias
atrial fibrillation
ventricular tachycardia
brady arrhythmia are
SLOW less common,
rhythm maintained by pacemaker,
basal heart rate is 30bpm without – cannot stand
2 types of brady arrhythmia
- heart block
- drug induced (beta blocker, digoxin)
cardiac pacemakers
Electronic boxes used to treat BRADYARRHYTHMIAs
Keep heart rate at a minimum level. Beats at a set rate.
risk with cardiac pacemakers
theoretical risk of electrical interference (as looking for very small electrical heart signals)
- electrical fields - MRI, electrosurgery/diathermy
- dental equipment THEORETICAL risk only (some electrical scalers)
- Pulp Testers OK - avoid INDUCTION scalers
how an cardiac pacemaker works
Wire to see if heartbeat, and a wire to make cardiac muscle beat if no beat
- Sit and do nothing if happy level of beats, will kick in if HR drops e.g. due to blockage
Wire up through subclavian into superior vena cava and into right ventricle – sensing how often ventricle contracting compares against programme normal
when are cardiac pacemakers used
to treat bradyarrhythmias
- kick in if HR drops
sinus rhytm
PQRST wave
P wave – atrial depolarisation
QRS complex – Ventricular depolarisation
- Narrow signals move quickly
- Size of spike on size of muscle
- Width of spike depends on conduction
T wave – Ventricular repolarisation
ventricular fibrillation appearance on graph
Big broad irregular spikes – different bits conducting at different times
ventricular fibrillation is
Unstable heart electrical activity
- Heart attack
- Electrocution
- Long QT syndrome (can be worsened by medicines)
- Wolf-Parkinson-White syndrome
No cardiac output
- Death follows!
Treat with ‘Defibrillation’
- Implanted defibrillators used in risk cases
consequence of ventricular fibrilllation
No cardiac output
- Death follows!
Treat with ‘Defibrillation’
- Implanted defibrillators used in risk cases
asystole is
Lack of any electrical activity
Wandering line
- Not flat line (not plugged in correctly)
atrial fibrillation appearance on graph
Appears normal but no P wave
- Regularity of heartbeat gone
QRS is irregularly spaced
asystole appearance on graph
Wandering line
- Not flat line (not plugged in correctly)
atrial fibrillation is
Irregularly irregular heartbeat
- Regularity of heartbeat gone (QRS is irregularly spaced)
Common – managed with anticoagulants
As can develop blood clots in atria and lead to stroke
how is atrial fibrillation managed
managed with anticoagulants
- As can develop blood clots in atria and lead to stroke
graph of heart attack
ST elevation
