chronic CVS diseases Flashcards
what are values of bp to be considered hypertension
- higher than 140/90
risk factors for hypertension
age
smoking
alcohol
genetics
pregnancy
stress
drugs
which drugs could cause hypertension
o NSAIDs
o corticosteroids
o oral contraceptives
Possible causes of hypertension
- Phaeochromocytoma
- Cushing’s syndrome
- Renal artery stenosis
what is cushings syndrome
salt and water retention leading to excess fluid and hypertension
what is Renal artery stenosis
o usually a result of atherosclerosis
o narrowing of blood flow into kidney
o In response to this reduced blood flow, the kidneys activate RAAS#
o increase in aldosterone and angiotensin II
o increase in water and salt retention; vasoconstriction
o hypertension
What can happen after you have hypertension
- atherosclerosis
- MI
- stroke
- peripheral vascular disease
- renal failure
CVS Diseases linked to hypertension
- cerebrovascular accident stroke
- coronary heart disease
- heart failure
does treating hypertension decrease the risk or effects of coronary heart disease?
no
treating hypertension has very little effect on coronary heart disease because reversing pressure does not reduce the amount of plaque that has bult up in the coronary arteries over the years
does treating hypertension decrease the risk of heart failure
yes, lesser workload on heart
what is heart failure
o heart failure is when the heart is unable to pump blood around the body
Investigations for hypertension
- urinalysis
- serum biochemistry
- serum lipids
- ECG
- cortisol or adrenaline levels
Treating hypertension
- modify risk factors
- drug
what drugs are used to treat hypertension?
diuretics
beta blocker
calcium channel antagonist
ACE inhibitors
side effects of diuretics
gout and xerostomia
side effect of b blocker
worsen heart failure
worsen asthma and copd
side effect of calcium channel antagonists
cause gingival hyperplasia
side effects of ACE inhibitors
angiodema
Oral mucosa and upper airways including swelling of the lips, tongue, and floor of mouth
4 types of heart failure
high/low output
left/right heart failure
what is high output heart failure
demands of the system have increased beyond the capacity of the pump
causes of high output heart failure
anaemia - o2 capacity reduced
thyrotoxicosis - increased metabolism-> increased o2 requirement
what is low out heart failure
pump is failing
what happens when the ventricles become enlarged or stiff
- enlarged ventricles -> ventricles pump out less than 40-50% of the blood
- stiff ventricles -> ventricles pump out 60% of blood but the total volume is less than the volume of normal heart
causes of low output heart failure
cardiac defect
valve disease
heart muscle disease
MI
myocarditis
pressure overload
hyper tension
aortic stenosis (valves)
volume overload
arrhythmia
afib
heart block
drugs beta blocker
when looking at signs and symptoms of heart failure, how to differentiate between left and right heart failure?
- left heart failure
o lungs accumulate fluid
o systemic tissues - right heart failure
o venous pressure elevated
o systemic veins
o fluid transudation from veins into tissues
o swollen ankles
pitting oedema suggests what
right heart failure
*for pitting oedema, the higher the pitting is found along the leg, more severe failure
Treatment of heart failure
acute emergency lungs filled with fluid -> use high dose diuretic to remove fluid
chronic ->
o improve myocardial function
o reduce compensation effects
o treat underlying causes
o drug therapy
drugs used for chronic heart failure
diuretics
ace inhibitors
inotropes digoxin – improves heart efficiency and control electrical activity
nitrates – reduce venous filling pressure, reduce fluid transudation from veins to tissues, reducing swelling
whats a negative inotype
inotropy is the strength of heart pumping
beta blockers are a negative inotrope so it can worsen heart failure, heart fails as a pump
which valves are more likely to have problems in valve disease
- mitral valve ie bicuspid
- aortic valve
valve stenosis
narrowing of the valve opening, unable to open
valve insufficiency
unable to close
Causes of valve diseases
congenital
MI
rheumatic fever->vegetations
dilatation of aortic root->valve cant close, might rupture and lead to aneurysm
when to use Doppler ultrasound scan
valve disease
congeintal heart disease
Treatment for valve disease
- valve replacement with prosthetic valves
what drug do you prescribe for stents and prosthetic valves
stent - aspirin
pros valve - warfarin
metal vs porcine valves
metal longer lifespan but need warfarin
both might need AB prophylaxis
recognize sinus, asystole, ventricular fibrillation
know about atrial fibrillation and ECG of MI
whats Afib and Atrial tachycardia
atrial tachycardia can lead to atrial fibrillation
With Afib, electrical impulses fire from multiple sites in both atria instead of the single SAN. That can cause the atria to contract 400 or more times per minute
which arrythmia has narrow QRS complex
afib
which arrythmia has broad QRS complex
ventricular tachycardia
why is Afib less dangerous than VT/VF
Ventricles all activated at the same time so still not as bad as ventricular tachycardia
ventricular tachycardia-> ventricular fibrillation -> death
what happens during ventricular fibrillation
ventricle muscles not contracting together, contracting at different paces at different times
no ability to produce a cardiac output
requires defib
when is defib used
defib used for VF,VT,PVT
- defib cannot sense asystole, it requires existing electrical activity , cannot generate any electrical activity
two types of bradyarrhythmia
heart block
drug induced( beta blocker)
whats heart block
little to no conduction through SAN -> AVN;
ventricle has independent pulse of about 30bpm
what does the ecg of a heart block look like
prolonged PQ intervals
how many degrees of heart block
3
3rd being complete heart block
Treatment of bradyarrhythmia
- pacemakers
- has a sensing circuit
- pacing circuit
what is the relation between pacemakers and dental
- electrical fields, MRI, some dental equipment, induction scalers cannot be used as they might cause sensing circuit to shut down
when to suspect congenital heart diease
- suspect with any congenital defects like cleft lip, down syndrome
3 types of congenital heart disease
- Atrial septal defect
- Ventricular septal defect
- Patent ductus arteriosus
is atrial and ventricular septal defect cyanotic?
no, blood is still oxygenated
what can atrial defect lead to
may lead to heart failure or atrial hypertrophy
due to increased workload of recirculating the blood through lungs
what can ventricular defect lead to
higher risk of endocarditis due to turbulent blood flow
higher risk of heart failure
Patent ductus arteriosus
ductus fails to close
blood flows from aorta into pulmonary artery
blood simply recirculating ; no cyanosis
increased cardiac workload which may lead to heart failure
Signs and symptoms of congenital heart disease
finger clubbing
central cyanosis not peripheral
cyanosis definition
o more than 5g/dL of deoxygenated Hb in the blood
o poor blood flow through lungs to tissues
warm tissues look blue in colour
tongue and lips looks blue
what could be happening
central cyanosis, congenital heart disease, mixing of oxy and deoxy blood
Treatment of congenital heart diseases
- septal defects may close naturally with time
- open heart surgery to close defect
- insertion of mesh
- AB prophylaxis for some dental procedures can be considered
Infective Endocarditis def
- infection and inflammation of the endocardium
- usually on the valves
cause of IE
- mainly oral streptococci
- microbial colonisation of thrombi on endocardial surface
pathogenesis of IE
- bacteria enter -> adhere to damaged endothelium/valve and thrombi -> bacterial proliferation, neutrophil and macrophage infiltration -> vegetation formation on valves usually -> haemodynamic changes -> laminar changes to turbulent flow -> more vegetations and microbial multiplication
Who is at risk of IE
- congenital heart defects
- prosthetic valves
- past history of endocarditis
What dental procedures are a risk
- involving dento-gingival junction
- bacteraemia = bacteria in blood
- extractions
- perio therapy
- gingival surgery
- implants
- restoration involving gingival margin and matrix bands
Who is not at risk of IE
- CABG
- angioplasty and stent
- pacemakers
- defib
How to handle at risk patients for IE?
- identify the risk
- prevention of oral disease
- let them know that AB prophylaxis is no longer routinely administered
- consult cardiologist if they are at risk
side effects of AB prophylais
- AB prophylaxis may cause side effects like risk of hypersensitivity for ppl with penicillin allergy, anaphylactic shock, increase risk of CDI (C.difficile infection)
what does NICE, ESC AND AHA say about AB prophylaxis
NICE=AB ineffective
ESC and AHA= AB effective
when should you as a dentist give AB prophy
- prescribing AB prophylaxis should be made by patient and their cardiologist
- communicated to dentist in writing
- only used for procedures that may produce bacteraemia eg manipulation of dento gingival junction
dosage of AB prophylaxis
3mg amoxicillin 1h before procedure
Valve defects are common is who?
Elderly and Down syndrome