Pathology of the cardiovascular system Flashcards
(38 cards)
What is Atherosclerosis?
Calcified plaques in the intima of large and medium sized arteries
* They begin as fatty streaks, some of which progress to plaques
* Plaques can progressively enlarge causing stenosis and ischemia
* They can rupture causing a thrombus formation, total occlusion and critical ischemia
* Can put pressure on the underlying media causing an aneurysm
* Risk factors
o Increasing age
o Hypertension
o Smoking
o Diabetes
o Family history
o Alcohol
o Obesity
o
o Conditions it can cause include
§ Ischemia / infarction – MI, angina, cardiac failure, TIA, stroke, peripheral vascular disease
§ Aneurysmal dilation- thoracic or abdominal aortic aneurysm
What is heart failure? description, causes, symptoms
Description
o Describes cardiac ventricular dysfunction – the heart cannot pump enough blood around the body to
meet the body’s blood flow requirements. Used to be called congestive heart failure
- Causes
o Most common in older patients
o Coronary heart disease
o High blood pressure
o Cardiomyopathy
o Arrhythmias, such as atrial fibrillation
o Damage to the heart valves
o Congenital heart disease
o Lifestyle factors – obesity, anaemia, excess alcohol, pulmonary hypertension - Symptoms
o Breathlessness at rest or after activity
o Exhaustion most of the time
o Fainting / feeling lightheaded
o Swollen ankles and legs
Heart failure: diagnosis, complications, treatment, and differential diagnosis
Diagnosis
o Blood tests to check for damage (peptides signal stress on the heart, CRP indicates inflammation, BNP to diagnose
heart failure)
o ECG and / or echocardiogram
o Spirometry
o CXR - only about 70% accuracy. But may see pulmonary venous congestion, cardiomegaly, pulmonary oedema, pleural
effusions.
o US is the most common imaging used – transthoracic echocardiography. It can assess the appearance and function of
the ventricles, assess the valve anatomy and function and look at the pericardial space
o Cardiac CT can provide estimates of cardiac function and visualisation of cardiac structures
o Cardiac MRI can prvide highly accurate ejection fractions, identify abnormalities and is considered the gold standard
imaging modality.
o Complications
o Prognosis is poor – up to 70% of patients die within 5 years.
o Acute pulmonary oedema
o Arrhythmias such as ventricular tachycardia (can lead to VF and death)
o Treatment
o Make healthy lifestyle changes
o surgical management
§ Implantable ICD or PPM, cardiac transplant
o Treatment of complications
o Medication – betablockers most commonly
o Differential diagnosis
o Pneumonia
o PE
o Asthma
Potential areas for trans thoracic echocardiogram blind spots:
Pericardium
Aorta
left ventricular apex
cardiac valves
left atrial appendage
coronary arteries
extracardiac structures
What is Pericardial effusion?
Description
o Occurs when excess fluid collects in the pericardial space (normally 30-50ml)
- Causes
o Many! Including pericarditis (inflammation of the pericardium due to injury or disease), MI, RA, metastasis, particularly lung and
breast. - Symptoms
o Presentation relates to the speed fluid has accumulated. Patients will have impaired cardiac function, due to the pressure.
o Symptoms can include dyspnoea, reduced exercise tolerance. - Diagnosis
o CXR – need at least 200ml of fluid to see on a CXR. But may see heart enlargement (looks like a water bottle), pulmonary oede
o Echo – method of choice as you can measure the amount of fluid and assess the impact on cardiac function
o CT/ MRI – pericardium thickness of more than 4mm is considered abnormal - Complications
o Can lead to cardiac tamponade and death. - Treatment
o Small amount of fluid is usually managed conservatively
o Large amount – can be drained - Differential diagnosis
o Cardiomegaly of another cause
What is Mitral valve regurgitation?
Description
o Condition where the mitral valve leaks during systole (pumps blood into arteries) and so blood flows in the wrong direction from the
left ventricle into the left atrium
- Causes
o Chronic - Increasing age, congenital heart defects, calcium buildup preventing the valve from correctly functioning, cardiomyopathy
o Acute – MI, trauma - Symptoms
o Acute – severe symptoms of heart failure, shock
o Chronic – heart murmur on examination, dyspnoea, arrhythmia or palpitations - Diagnosis
o CXR – signs of left atrial enlargement (splaying of the carina, loss of the left atrial appendage), features of heart failure, pulmonary
oedema
o Echo – useful for assessing the cause and reviewing the left ventricle
o CT / MRI – not commonly used but may have some uses in assessing the underlying cause - Complications
o Heart failure, pulmonary hypertension, AF, sudden cardiac death. - Treatment
o Acute – mitral valve replacement
o Chronic – Drugs such as ACE inhibitors, anticoagulation. - Differential diagnosis
o Any causes of an enlarged heart and heart failure
What is Coronary artery disease?
Description
o This mainly refers to the narrowing of the coronary arteries due to atherosclerosis (calcification). This results in
myocardial ischaemia and globally is the leading cause of death
- Causes
o Atheroschlerosis. - Symptoms
o May be asymptommatic but include chest pain and angina symptoms - Diagnosis
o Coronary angiography and CTCA both look for luminal narrowing. - Complications
o MI due to complete artery occlusion
o Heart failure - Treatment
o Drugs to vasodilate and reduce blood pressure. Anticoagulation.
o Stents
o Coronary artery bypass grafts - Differential diagnosis
o Pericardial effusion, pneumonia, aortic dissection etc
What is Coronary artery bypass graft (CABG)?
Surgical procedure to increase blood flow to the
myocardium due to coronary artery stenosis
* Both arteries and veins can be grafted, often from the
patient’s leg or arm.
* Often grafted onto the left internal thoracic artery.
* Post CABG patients can develop
o Pleural or pericardial effusions
o PE
o Infection
What is Atrial fibrillation?
Description
o Is a supraventricular tachycardia with uncoordinated atrial electrical activation, and ineffectual atrial
contraction leading to an irregular and often abnormally rapid ventricular rhythm – an arrhythmia)
Atrial fibrillation (AFib) is an irregular and often rapid heart rhythm caused by disorganized electrical signals in the upper chambers of the heart (atria). (Arrhythmia)
- Causes
o Hypertension, ischaemic heart disease, heart failure, valvular heart disease, lifestyle - Symptoms
o Often asymptomatic
o May have an irregular pulse, dyspnoea, chest pain, dizziness, syncope (fainting). - Diagnosis
o ECG, identifying the underlying cause. - Complications
o Stroke, heart failure, increased all cause mortality. - Treatment
o Anticoagulation for stroke prevention, drug treatments for rate control, cardioversion, PPM
What is Abdominal aortic aneurysm?
Description
o Also called a AAA
o Focal dilatation of the abdominal aorta > 3cm in diameter
- Causes
o Increasing age, males more affected. - Symptoms
o Most are asymptomatic until they rupture so often an incidental finding.
o Patients may have pain or a pulsatile mass - Complications
o Rupture – 70% mortality before surgery - Treatment
o Generally, surveillance for less than 5cm and surgery for >5cm.
o May have an EVAR procedure - Differential diagnosis
o Aortic dissection
CT: Abdominal aortic aneurysm
Gold standard for
evaluation, but high
radiation dose
* Best for preoperative
planning as can relate
aneurysm to branch
arteries and the aortic
bifurcation
* If ruptured may see a
retroperitoneal blood clot
US: Abdominal aortic aneurysm
Best for screening and surveillance due to speed and no
radiation dose
* Sensitivity and specificity of nearly 100%
* But can be affected by patient body habitus or overlying
bowel gas
* Cannot plan surgery from US alone
What is EVAR?
Endovascular aneurysm repair
* For both elective and
emergency repair
* Inserted via the common
femoral artery.
* Complications include endoleak,
stent migration, infection
* Patients need lifelong
monitoring to monitor the graft
and check for complications
Atherosclerosis in the lower limbs /
peripheral arterial disease
Description
o Plaques causing stenosis in the arteries of the legs.
- Causes
o Risk factors include
§ Diabetes, smoking, advancing age, hypertension, obesity - Symptoms
o Leg pain when walking, cramping in the thigh or calf, weakness or pins and needles in the lower legs or feet, coldness
in the feet, weak pulse in the feet - Diagnosis
o On plain film you may see atherosclerotic plaques in the vessels
o US – can evaluate the arterial wall. US will see calcification as hyperechoic foci and when large, acoustic shadowing.
o CTA – uses contrast to look for luminal narrowing - Complications
o Severe pain, critical limb ischaemia, death of tissue due to infection, amputation due to gangrene - Treatment
o Lifestyle changes
o Angioplasty or bypass graft - Differential diagnosis
o Gout, arthritis
What is Stroke -
Ischaemic?
Description
o A stroke is a sudden onset of focal neurological deficit of
presumed vascular origin
o An ischaemic stroke (87%), is due to infarction in the central
nervous system. There is interruption of blood flow
through an intercranial artery leading to deprivation of
oxygen. If circulation is not re-established there will be
cell death.
- Causes
o Artheroschlerotic, tumour, thrombus, hupertension - Symptoms
o Paralysis or numbness of face, confusion and difficulty speaking, headache, vision
problems, unilateral weakness - Complications
o Can haemorrhage, can have complications such as aspiration pneumonia and PE.
Seizures, - Treatment
o Need to have fast treatment to encourage reperfusion
o Thrombolysis, clot retrieval - Differential diagnosis
o Ischaemic versus haemorrhagic
Stroke – ischemic - CT diagnosis
In ischemic stroke patients often have 3 scans
o Non contrast CT brain – ischemic or hemorrhagic
o CT perfusion – functional scan
o CT angiography – identify the location of a clot / narrowing
o CT is the most often used primary imaging method. It is quick, inexpensive and
available
o But is limited in the acute phase – may not show changes in the deep grey matter in
the early phase
o Aim of CT in the acute phase are to
§ Exclude hemorrhage, which would preclude thrombolysis
§ Look for any signs of ischemia
§ Exclude other causes like a tumour
§
o Earliest CT sign is a hyperdense vessel sign – representing the clot
o As time progresses and changes become chronic you will see low density.
Stroke – ischemic - MRI diagnosis
More time consuming but
has a higher sensitivity
and specificity for
diagnosing ischemic
infarction in the initial
stages
* Impact of early MRI in isch emic strokes beyond hype r-acute stage to improve p atient outcomes, enable e arly discharge, and realize cost savings - Journal of S troke and Cerebrovascular
Diseases
What is Stroke - hemorrhagic?
Description
o Is a type of intracranial haemorrhage, defined by accumulation of blood in the brain parenchyma (functional tissue).
Happens when there is a rupture of a small blood vessel.
- Causes
o Can be spontaneous or can be from an ischemic stroke, a vascular malformation, a tumour or metasteses - Symptoms
o Similar to those of an ischemic stroke. Patient is more likely to have decreased consciousness. May also have
headache, nausea and vomiting and seizures - Complications
o Seizures, swelling of the brain, memory loss, vision and hearing problems, death - Treatment
o Management is time critical.
o Blood pressure needs to be controlled, management of any raised intercranial pressure (drain), surgery to evacuate the
blood, management of seizures - intubation - Differential diagnosis
o Ischemic stroke
Stroke – hemorrhagic - CT diagnosis
Usually the first modality
used
* Imaging findings
o Hyperdense blood, often
with surrounding
edema
o May also see midline
shift, hydrocephalus
(increase in CSF and
enlarged ventricles)
Stroke – hemorrhagic - MRI diagnosis
Findings depend on the
size and age of the blood
* Can also show causes –
small vessels1
What is Subarachnoid Haemorrhage?
Also called a SAH
* Description
o Is a type of intracranial hemorrhage with
blood in the subarachnoid space
- Causes
o There are 2 causes
§ Trauma
§ Spontaneous – which can be due to a
ruptured aneurysm, various malformations
(AVM, SAM), anticoagulation therapy
o Risk factors include:
o Patients tend to be older middle age, often
less than 60
o Family history
o Hypertension
o Heavy alcohol comsumption
o Abnormal connective tissue
Symptoms
o Thunderclap headache
o Collapse and loss of consciousness
- Complications
o Elevated intracranial pressure – may require a drain
o Ischaemia (may require balloon angioplasty)
o Neurogenic pulmonary oedema
o PEA (no measurable cardiac output at cardiac arrest – non shockable rhythm) - Treatment
o Varies depending on the underlying cause - Differential diagnosis
o Meningitis
o Post thrombectomy iodine extravasation
Subarachnoid hemorrhage - CT diagnosis
CT normally performed first due to
availability
* Will see hyperdense material in the
subarachnoid space – most commonly
around the circle of Willis
Subarachnoid hemorrhage - MRI disgnosis
MRI is more sensitive than CT
at both identifying
hemorrhage and diagnosing
the underlying cause
* BUT – poor availability, longer
scan, greater difficulty with
unstable and ventilated
patients
* Will see blood as a
hyperintensity in the
subarachnoid space on FLAIR
