Cardiovascular disorders Flashcards
Describe arteries
Thick walled high pressure vessels which conduct the blood from the heart to the tissues
Describe veins
Thin walled lower pressure vessels returning blood to the heart
Name the different valves of the heart
Mitral valve
Aortic valve
Tricuspid valve
How does the myocardium relieve its blood supply
Via the right and left coronary arteries
Name the main cause of cardiovascular disease
- Coronary heart disease
- Cerebral vascular disease
Give examples of cardiovascular disease
- Atheroscleoriis
2.
What does atherosclerosis affect
Only the arteries
What is the cause of atherosclerosis
Unknown
What are the risk factors of atherosclerosis
- Smoking
- Hypertension
- Diabetes melitus
- Hypercholesterolaemia
- Family history of cardiovascular disease
- Sedentary lifestyle
- Obesity
- Age
9, Excess alcohol - more men tend to get it than women
Which arteries are most affected by Atherosclerosis
Medium and large Calibre arteries
Name the 3 morphological stages of atherosclerosis
- Fatty streak
- Fibrolipid plaque
- Complicated plaque
What is the fatty streak
Accumulation of lipid in intima of the artery wall
Describe the fibrolipid plaque
Deposition of collagen and progressive fibrosis
Lesion has a fibrous cap that bulges into the lumen of the vessel
What can happen in the complicated plaque phase
The fibrous cap becomes unstable and develops surface defects referred to as ulcers of intraplaque fissures
What can intraplaque fissures cause
It exposes blood to plaque contents and consequently thrombosis develops over the plaque
What are the consequences of thrombosis
May partially or completely occlude the vessel limen
In which vessels can thrombus cause a serious issue
Narrow vessels such as the coronary arteries
What can partially occlude thrombi cause
Embolisms
What can damaged arteries show
Progressive calcification which can cause gradual permanent dilation of the artery forming an aneurysm
Give examples of classes of drugs that can be used to prevent atherosclerosis
- Statins
- Fibrates
- Nicotinic acid
- Ezetimibe
- Bile acid sequestrates
Name the first line of trematn for atherosclerosis
statins
How do statins work
They hinder the cholesterol synthesis by inhibiting the enzyme 3 hydroxy 3 methylglutaryl co enzyme A
What is a dental side effect of statins
Myopathy
When is the chance of myopathy increased in a patient taking statins
If the patent is also on erythromycin
Name the arteries most commonly effected by atherosclerosis
- Coronary arteries
- Cerebral arteries
- Aorta
- Mesenteric arteries
- Iliac and femoral arteries
What does atherosclerosis of the coronary arteries cause
Angina
What does thrombosis of the coronary arteries cause
Myocardial infarction
What can thrombosis over places in the vessels at the base of the brain cause
Cerebral infarction (Stroke)
What can thrombosis of atheroma within the aorta cause
Symptoms associated with systemic embolism and aortic aneurysm
What can thrombosis over plaques in the mesenteric vessels produce
Small bowl infarction, rupture and subsequent peritonitis
What can atheroma of the iliac and femoral vessels cause
Intermittent claudication (leg pain and weakness bough on by walking)
What can thrombosis of the iliac and femoral vessels cause
Gangrene of the lower extremities
What is an aneurysm
A localised permanent abnormal dilation of a blood vessel due to weakening of the blood vessel wall
Name the most common aneurysms
Those that develop as a consequence of atheroma
Where do atherosceloritc aneurysms form
Either at the arch of the aorta, the thoracic aorta or within the abdominal aorta just above the bifurcation of the iliac arteries
What serious risk do aneurysms pose
Risk of rupture
What can a ruptured aneurysm cause
A torrential and often fatal retroperitoneal bleed
What does berry aneurysm affect
The circle of willis at the base of the brain
Describe the berry aneurysm
A small saccular dilation that develops at points of breaching on the circle of willis
In whom is the berry aneurysm common
Typically develops in young hypertensive individuals who have a defect of the muscular wall of the arteries that comprise the circle of willis
What can rupture of a berry aneurysm cause
Subarachnoid haemorrhage
Other than predisposition and genetics what else can cause aneurysms
Infections such as gang (mycotic) and syphilitic
What are myocitic aneurysms a consequence of
Localised infection of an arterial wall
Name one well recognised source of infection that can lead to aneurysms
Embolic material produced during infective endocarditis
These can produce a mycotic aneurysm at the site of impaction
What can rupture of an aneurysm in the cerebral vessels cause
Cerebral haemorrhage
What is a syphilitic aneurysm caused by
chronic infection with Treponema pallidum
Name the most common site for a syphilitic aneurysm
Root of the aorta
What are Microaneurysms
Aneurysms forced within capillaries
Which vessels are commonly affected by Microaneurysms
Cerebral and retinal capillary
In whom are Microaneurysms seen in
Hypertensive patients
Diabetics
What is a dissecting aneurysm also known as
a false aneurysm
Why is a false aneurysm given this name
As is it actually a blood filled space caused rupture of the aorta rather than dilation of the vessel
What is the term for a blood filled space
Haemotoma
Where are dissecting (false) aneurysms most commonly found
At the arch of the aorta
In which patients is a dissecting (false) aneurysm seen
Usually elderly and hypertensive patients
Also seen in patient witch connective tissue abnormalities eg marinas syndrome
What do patients with a dissecting (false) aneurysm present with
Severer inter scapular back pain, loss of peripheral pulses or fatal haemopericardium and/or retroperitoneal haemorrhage.
What is a thrombus
A solid mass of blood constituents formed within the vascular system during
What is an embolism
A mass of material flowing free in the vascular system able to become lodges within a vessel and block its lumen
What is Ischaemia
An inappropriate reduction in blood sappy to an organ or tissue
What is infarction
Death of tissue due to its ischaemia
Name the 3 factor that predispose a person to the formation of a thrombus
1.. Changes in the surface of the vessel
2. Pattern of blood flow
3. blood constituents
What are the 3 factors that predispose a person to the formation of a thrombus known as
Virchows triad
Where can thrombosis occur
Within the arterial or venous system and within the heart
What is a thrombosis within the heart called
Cardiac thrombosis
Where does arterial thrombosis occur
On atheromatous plaques
Describe the platelets found in a person who smokes tobacco
They are abnormally sticky
Describe atheromatous plaque
It protrudes into the lumen of the artery and disturbs the laminar flow of blood setting up local turbulence
What can turbulence in the lumen of an artery cause
Can produce shear forces that can cause endothelial ulcerations
What do endothelial ulcerations lead to
platelet aggregation
activation of coagulation cascade and deposition of fibrin
Describe the different layers of a thrombus
alternating layers of platelets `and fibrin and erythrocytes
This forms a lamellate structure
Where do the incremental layers of a thrombus tend to accumulate
On the downstream side of the atheroma and hence the thrombus grows in the direction of the blood flow
Give soem risk factors of deep vein thrombosis
- Oestrogen replacement therapy or the oral contraceptive pill
- Smoking
- Immobility
- History of pelvic surgery
- Previous history of deep vein thrombosis
- Pelvic tumours
- Pregnancy
- Surgery
Where does venous thrombosis tend to imitate
At the valves
What do venous thrombosis develop as a consequence of
Venous state and other predisposing factors such as phlebitis
What happens to a vein following thrombosis
Tends to become inflamed
What is inflammation of the veins following thrombosis called
thrombophlebitis
Name the most common veins to be affected by venous thrombosis
Deep veins of the leg
What are the typical clinical signs of deep vein thrombosis
Swollen and painful leg
What is the most clinically important consequence of deep vein thrombosis
Pulmonary embolism
What does cardiac thrombosis typically affect
- Chambers of the left side of the heart
- Walls of the heart (mural thrombus)
- Heart valves
What is arterial thrombosis caused by
Atrial fibrillation and mitral valve stenosis
Where does ventricular thrombosis occur
At the site of myocardial infarction
What is valvular thrombosis a feature of
Rheumatic dever
Infective endocarditis
Is thrombosis reversible
In some cases it can be if the thrombus is broke down by the fibrinolytic pathway
What is the reversal of a thrombus called
Lysis and resolution
Can a thrombus heal
Yes if granulation tissue grows into the thrombus and there is organisation and fibrosis
What does healing of a thrombus cause
Retraction of the thrombus and the patency of the vessel lumen being restored
Other than healing or several what can happen to a thrombus
Progressive fibrosis and scarring of thrombus and vessel wall can result in a permanent stenosis (narrowing) of the vessel.
What is an embolus
A mass of material in the vascular system able to become lodges within a vessel and block its lumen
Where is embolic material usually derived from
Thrombus
Other than thrombus what are soem other causes of embolism
- atheromatous debris
- heart valve vegetations
- tumour emboli
- fat droplets
- amniotic fluid
- gas (caisson disease)
- foreign material.
What can embolism cause in terms of Cardiovascular disease
Thrombotic debris which can result in sudden death
Name the most clinically recognised embolic event
Pulmonary embolism
What is pulmonary embolism usually derived from
Fragments of a deep vein thrombosisocated in the calf or ileofemoral venous segment.
How does a pulmonary embolism occur
- Fragments of a thrombus become detached from the development site in the vein
- the fragment travels through the venous system to the right side of the heart
3.Embolus is then pumped out through the pulmonary arteries into the lungs
What are the clinical effects of a pulmonary embolism determined by
The size of the embolus
Where can a large embolus get lodged
at the bifurcation of the pulmonary arteries - saddle embolus
Where Can a small embolus get lodged
In the peripheral branch of the pulmonary artery resulting in a wedge shaped infaract go lung tissue
what would a patient with a small lodged embolus complain of
Chest pain
Breathlessness
Coughing up blood
What are systemic embolisms derived from
Thrombus within the left side of the heart or hrombus formed on atheromatous plaque
What can embolism to the cerebral vessels case
cerebral infarction and stroke
What can emboli lodging into the speed or kidney cause
Segmental infarcts which are usually asymptomatic
What can emboli lodging int eh mesenteric vessels cause
Death of large segments of small intestine with bowel perforation and peritonitis.
What is the progression of ischaemia to infarction determined by
- Vascular anatomy
- Duration of occlusion
- Metabolic requirements of the tissue
4.General circulation - Anaemia
- Concept of reperfusion injury
List some of the symptoms of cardiovascular disease
- Chest pain
- Breathlessness / dyspnoea
- Raised pressure in the systemic veins and capillaries
- Swelling of the ankles and legs
- Palpitations
- Syncope
How might the patient describe chest pain they are having due to cardiovascular disease
Tigh and hack pain across the chest that may radiate to the arms the neck and jaw
What is chest pain characteristically Brought on by in cardiovascular disease
exertion
What can chest pain be accompanied with in an MI
Sweating
nausea
breathlessness
palpitations
What does the term palpitations refer to
An abnormal awareness of the heart beat
What are palpation’s usually a symptom of
Cardiac arrhythmia
List some differential diagnosis of chest pain
- Myocardial infarction
- Angina
- Gastro-oesopheal reflux disease
- Pleuritic pain
- Musculoskeletal pain
- Pain secondary to trauma
- Panic attack
What is syncope
A loss of consciousness due to lack of blood flow to the brain
How can breathlessness be detected
By observation and measuring the respiratory rate
What is considered an abnormal respiratory rate
Anything greater than 20 breaths per min
What can pallor indicate
Anaemia
Poor cardiac output
Where ca =n we measure the pulse
- At the radial artery in the wrist
- Brachial artery on the medial side of the arm in front of the elbow
- Carotid below the angle of the jaw
What is a normal pulse rate
60-100 beats per min
What does a completely irregular pulse usually indicate
Atrial fibrillation
What can a weak or thready pulse indicate
Poor cardiac output or shock
What can a strong pulse indicate
Can indicate a state of vasodilation such as thyrotoxicosis or pyrexia due to infection
What can a raised jugular venous pressure indicate
A sign of venous congestion in heart failure
What can chronic elevation of the venous pressure result in
A detectable pitting oedema of the ankles
What is peripheral cyanosis
A blue tinge due to deoxygenated blood in the peripheral circulation
What can peripheral cyanosis indicate
Peripheral arterial insufficiency
Shock
Heart failure
How is central cyanosis detected
In the lips and tongue
What does central cyanosis indicate
Reduced oxygenation of the arterial blood leaven the left side of the heart more commonly seen in lung disease
Give examples of what blabbing of the fingers can indicate
- Chronic lung disease
- Inflammatory bowel disease
- Infective endocarditis
- Congenital heart malformations
Describe the fingers of a person with endocarditis
- more than 5 splinter haemorrhages in the nails (characteristic sign)
- Oslers nodes (rare)
- Janet spots (rare)
Describe splinter haemorrhages in the nails
They appear as small dark longitudinal marks under the nail
Describe Oslers nodes
Small painful nodules in the finger pulp
Describe laneway spots
Red marks in the palm due to capillaritis
What does a full examination of the cardiovascular system include
Examination of the heart lungs and pulses
What are heart murmurs
Sounds of turbulent blood flow due to dysfunction the heart valves
What do we use to carry out cardiac investigation
- ECG
- Exercise EXG
- Echocardiogram
- Ambulatory blood pressure monitoring
- 24 hour ECG tapes
- Angiography W
Where is an ECG recorded from
Skin electrodes placed over the chest and limbs
How do we diagnose iangina
ECG monitoring during graded exercise on a treadmill
What does echocardiography provide
Real life ultrasound images of the heart via a transducer moved over the chest wall
What can an echocardiogram show
The structures and function of the valves, the size and contractility of the chambers and can detect fluid in the pericardium
What does cardiac catheterisation involve
Involves the insertion of long catheters into the heart usually via the femoral artery and vein in the groin
What do cardiac catheterisation show
Measurements of the intra cardiac pressure and oxygen saturation to assess the function of the chambers and valves
How does MI typically present
With prolonged and severe ischameic type chest pain that is unresponsive to angina medications
List some associating symptoms of an MI
- Sweating
- Nausea
- Vomiting
- Palpitations
- Breathlessness
- Faintness
How is diagnosis of MI confirmed using an ECG
ECG usually shows elevation of the ST segment
What is the standard treatment for an MI
emergency thrombolysis with an intravenous infusion of streptokinase or recombinant tissue plasminogen activator.
What is the aim of mI treatment
To unblock the artery by dissolving the clot thereby minimising the damage to the myocardium
How is a diagnosis of angina often made
By using the clinical history
What is the initial treatment for angina
Sublingual GTN usually as a spray
