Structural Heart Disease Flashcards
What gives rise to the p wave on an ecg?
Atrial contractions.
What gives rise to the QRS complex?
Heart depolarising
What gives rise to the first sound after the first contraction?
Closing of the tricuspid and mitral valve.
Give congenital heart defect examples.
-Atrial septal defect (ASD)
-Ventricular septal defect (VSD)
-Tetralogy of Fallot (TOF)
-Coarctation of the aorta
What is tetralogy of fallot TOF? 4 things:
4 things:
- Ventricular septal defect- hole in wall between ventricles
- Pulmonary stenosis- where pulmonary valve is stenosed (narrowed down)
- Widening of aortic valve so that it sits in both left and right ventricle and allows for mixing of blood between them and into aorta
- Right ventricular hypertrophy- thickening of wall of right ventricle
What is Coarctation of the aorta?
- Narrowing of aorta
- Blood has to force its way through the narrowing so ventricle has to work harder to push more blood through that narrowing
- Leads to thickening of ventricles or heart failure
- Serious condition and needs urgent repair
Give examples of structural heart disease that develop later in life.
Valvular dysfunctions:
-Aortic stenosis
-Aortic regurgitation
Muscular dysfunctions: e.g cardiomyopathies.
What is aortic stenosis and regurgitation.
Aortic stenosis: Narrowing of the aortic valve.
Aortic regurgitation: Incompetence of aortic valve
Does rheumatic heart disease prevail highly in the younger or older population.
Younger population.
What comes before aortic stenosis?
Aortic sclerosis, (aortic valve thickening without flow limitation so patients can’t tell they have it).
How is aortic stenosis suspected?
By presence of an early-peaking systolic ejection murmurs and confirmed by echocardiography (where you see heart walls and can see thickening)
Risk factors for Aortic stenosis (8).
- Hypertension
- high LDL
- Smoking
- Elevated C-reactive protein
- Congenital bicuspid valves
- Chronic kidney disease
- Radiotherapy
- Older age
What are the causes of aortic stenosis?
- Rheumatic heart disease- commonest cause in developing countries
- Congenital heart disease
- Calcium build up
Describe the pathophysiology of aortic stenosis
Valvular endothelial damage stimulates inflammatory process which leads to deposition of calcium and leaflet fibrosis.
What changes in the heart does aortic stenosis then lead to?
Long standing pressure overload in left ventricle leading to left ventricular hypertrophy (LVH)
What happens in rheumatic heart disease?
It’s an autoimmune inflammatory reaction triggered by prior Streptococcus infection that targets the valvular endothelium, leading to inflammation and eventually calcification of valve
How do aortic stenosis patients present? (3)
- Exertional dyspnoea and fatigue
- Chest pain
- Systolic ejection murmur- more than 1/2 present with a crescendo-decrescendo pattern that peaks in mid-systole and radiates to the carotid
What do aortic stenosis patients usually have a history of?
- Rheumatic fever
- High lipoprotein
- High LDL
- CKD
- Age >65
What investigations are done for aortic stenosis?
- Transthoracic echocardiography- to see structure of heart
- ECH Chest X ray- to check for LVH
- Cardiac catheterisation
- Cardiac MRI
What kind of murmur does aortic regurgitation cause?
Early diastolic ejection murmur
What does aortic regurgitation cause if its chronic?
Congestive heart failure
What is aortic root dilation
Widening of the aorta
What can the causes of aortic regurgitation be divided into?
-Congenital causes and acquired.
-Aortic root abnormalities (dilation)
What are some examples of aortic root abnormalities that can cause aortic regurgitation?
Marfan syndrome, Ehlers-Danlos syndrome, and aortic dissection.
What are some examples of congenital abnormalities that can cause aortic regurgitation?
Bicuspid aortic valve, which is a condition where the aortic valve has only two leaflets instead of three.
What are some examples of acquired abnormalities that can cause aortic regurgitation?
Rheumatic fever
Infective endocarditis
Trauma to the chest
Connective tissue disorders (e.g. lupus).
What are the symptoms of aortic regurgitation?
Shortness of breath, fatigue, chest pain.
What happens in acute aortic regurgitation?
There is an increase in blood volume in the left ventricle during systole.
This leads to an increase in left ventricular end diastolic pressure and pulmonary venous pressure.
What does a person with acute aortic regurgitation experience?
The person experiences dyspnea and pulmonary edema.
What happens in chronic aortic regurgitation?
-There is a gradual increase in left ventricular volume, leading to left ventricular enlargement and eccentric hypertrophy.
-In the early stages, ejection fraction may be normal or slightly increased.
After some time, ejection fraction falls and left ventricular end systolic volume rises.
What can chronic aortic regurgitation eventually lead to?
Eventually, the person experiences dyspnea due to lower coronary perfusion, which can lead to ischemia, necrosis, and apoptosis.
What is eccentric hypertrophy?
A type of heart muscle growth where the heart chamber enlarges while the thickness of the heart muscle remains the same. This is a common adaptation in chronic aortic regurgitation.
How does acute AR present?
- Cardiogenic shock (heart can’t pump enough oxygenated blood to body esp brain)
- Tachycardia
- Cyanosis (skin/lips turning blue)
- Pulmonary oedema
How does chronic AR present? (2)
- Wide pulse pressure (big difference between systolic and diastolic bp)
- Pistol shot pulse (Traube sign)
-eccentric hypertrophy of lv
What investigations are done for AR? (4)
- Transthoracic echocardiography
- Chest X ray
- Cardiac catheterisation
- Cardiac MRI/CT scan
What is the main way of treating symptomatic AR chronic and acute.
Valve replacement and vasodilators.
What is mitral stenosis?
Mitral stenosis is a heart condition characterized by narrowing of the mitral valve, which controls blood flow between the left atrium and left ventricle of the heart.
What are the symptoms of mitral stenosis?
Symptoms of mitral stenosis include shortness of breath, fatigue, chest pain, and heart palpitations
What is the most common cause of mitral stenosis?
The most common cause of mitral stenosis is rheumatic fever, a complication of untreated streptococcal throat infections.
What are the potential causes of mitral stenosis?
Other potential causes of mitral stenosis include congenital heart defects, calcification of the valve, and certain medications.
How do you treat severe asymptomatic and severe symptomatic Mitral stenosis
-Severe asymptomatic: Balloon valvotomy
-Severe symptomatic: diuretic, balloon valvotomy, valve replacement & repair adjunct b blockers
What is mitral regurgitation?
Abnormal reversal of blood flow from left ventricle to left atrium
Most frequent valvular heart disease.
What are causes of acute mitral regurgitation? (5)
- Rheumatic heart disease
- Infective endocarditis
- Following valvular surgery
- Mitral valve prolapse
- Prosthetic mitral valve dysfunction
What are the 3 main types of cardio myopathies from most common to least?
-Dilated cardiomyopathy
-Hypertrophic Cardiomyopathy
-Restrictive cardiomyopathy
What happens to the heart in Dilated cardiomyopathy?
The heart becomes enlarge and weak.
What are some common causes of DCM?
DCM can be caused by viral infections, alcohol abuse, genetic factors, or other diseases.
Is HCM a genetic or acquired condition? (hypertrophic)
Genetic condition
What happens to the heart muscle in HCM?
In HCM, the heart muscle thickens, making it harder to pump blood effectively.
What can HCM lead to, especially in young athletes?
HCM can lead to arrhythmias and sudden cardiac arrest, especially in young athletes.
What happens to the heart muscle in RCM? (restrictive)
Ventricular walls are stiff and atria become enlarged. (Stiff heart)
What are causes of acute mitral regurgitation?
-Rheumatic heart disease
-Infective endocarditis
-Following valvular surgery
-Mitral valve prolapse
-prosthetic mitral valve dysfunction
What are causes of chronic mitral regurgitation? (5)
-Rheumatic heart disease
-Infective endocarditis
-SLE
-Scleroderma (autoimmune attack of connective tissues)
-Hypertrophic cardiomyopathy
-Drugs
What do you find on auscultation in people with Mitral regurgitation?
Diminished S1
What is S1?
The first heart sound, the “lub”
What kind of heart murmur to you get in mitral regurgitation?
Pansystolic murmur
How do we manage acute MR?
-1st line is emergency surgery
-Adjunct pre op diuretics
-Adjunct intra-aortic balloon counterpulsation
How do we manage chronic asymptomatic MR?
-1st ACE inhibitors
-Beta blockers, if left ventricular ejection fraction is <60% then surgery is first line
How do we manage chronic symptomatic MR? What do we do when ejection fraction is below a certain number and what is that number?
-First line is surgery plus medical treatment
-If ejection fraction is below <30% then 1st line is intra-aortic balloon counterpulsation
What is restrictive cardiomyopathy characterised by?
Diastolic dysfunction with normal systolic function,
Atrial enlargement occurs due to impaired ventricular filling during diastole (due to stiffening of ventricular walls), volume and thickness are normal
How do patients with restrictive cardiomyopathy present?
Comfortable when sitting, pitting oedema of extremities.
Increased jugular venous pressure.
Pulse volume is decreased.
