Structural heart disease Flashcards
What gives rise to the first heart sound during S1?
Tricuspid & Mitral valves closing.
What happens in the isovolumetric contraction phase of the cardiac cycle?
mitral and tricuspid valve close, Left ventricle contracts due to depolarisation, volume cannot increase due to mitral valve closing, LV pressure increases, pressure exceeds that of the aorta causing semilunar valve to open. Blood goes into aorta.
What gives rise to the T-wave on the ECG cycle?
Re-polarisation wave.
What causes the second heart sound (isovolumetric phase)?
Closure of the aorta and pulmonary valve.
What is Left ventricular end systolic volume?
volume of blood that stays in the left ventricle at the end of systole.
What is the Left ventricular end diastolic volume?
volume of blood left ventricle contains prior to ejection.
How do you calculate Stroke volume?
By taking the end systolic volume from the end diastolic volume.
What gives rise to the p wave on the ECG?
Atrial contraction
What happens in the atria during diastole?
Mitral valve opens, blood from the atria pools in LV, Atrial contraction happens briefly towards the end of filling (10%) , and plays a larger role when you are exercising (40%).
What are the two types of heart diseases?
Congenital heart diseases
Heart diseases that develop later in life
What are some Congenital Heart diseases?
atrial septal defect (ASD), ventricular septal defect (VSD), coarctation of aorta, patent foramen ovale (PFO),Patent ductus arteriosus (PDA), Tetralogy of Fallot (TOF)
What are some heart diseases that develop later in life?
can be due to valvular dysfunctions (Atrial stenosis /regurgitation or muscular (cardiomyopathies)
What causes a Ventricular septal defect?
Happens when the wall between the two ventricles fail to develop normally, leading to a whole in the wall, this can lead to mixing of oxygenated and deoxygenated blood.
Some can close as the child grows but with others you will need surgery to close the whole
What are the presentations for a Ventricular septal defect?
Poor weight gain, feeding.
Palpitations.
What is present in the Tetralogy of Fallot?
4 different effects which happen together;
Ventricular septal defect
Pulmonary stenosis - pulmonary trunk is narrowed down.
Widening of the aortic wall - sits on both ventricles, mixes blood.
Right ventricular hypertrophy - thickening of the wall of the right ventricle.
Multiple surgeries needed for normal breathing.
What is a Atrial Septal defect?
Whole in the wall between the 2 atria, develops due to failure of the walls development during pregnancy.
What is Coarctation of the Aorta?
Narrowing of the arterial wall in the descending aorta, during ventricular systole blood has to be forced through, requiring greater ventricular effort, this can cause thickening of the ventricle or heart failure.
What can happen due to a Aortic valve defect?
Aortic Stenosis
Aortic regurgitation
What can happen due to a Mitral valve defect?
Mitral Stenosis
Mitral Regurgitation
What is the biggest cause of valvular heart disease later on in life?
Rheumatic Heart disease
What age group is Calcific aortic valve disease most present?
> 80
What usually precedes aortic stenosis?
Aortic sclerosis - thickening of the aortic valve with flow limitations.
What gives an early suspicion of Aortic stenosis?
It is often suspected by the presence of an early-peaking, systolic ejection murmur, and confirmed by echocardiography.
What are the risk factors for Aortic stenosis?
Hypertension, LDL levels, smoking, elevated C-reactive protein, Congenital bicuspid valves, CKD, radiotherapy, old age.
What are the causes of Aortic stenosis?
Rheumatic Heart Disease
Congenital Heart Disease
Calcium build up
What is the Pathophysiology of Aortic stenosis?
Valvular endocardium is damaged due to abnormal blood flow or unknown cause. Inflammatory response leads to leaflet fibrosis & calcium deposits on the valve. This limits aortic leaflet motility and cause stenosis.
What does Aortic Stenosis lead to?
LV Hypertrophy
Left ventricular wall stress increases causes systolic function to decline with resultant heart failure.
What is the presentation for Aortic stenosis?
Exertional dyspnoea and fatigue
Chest pain
Ejection systolic murmur (≥3/6 is present with a crescendo-decrescendo pattern that peaks in mid-systole and radiates to the carotid)
H/O Rheumatic fever, high lipoprotein, high LDL, CKD, age >65
What investigations can be done to confirm Aortic stenosis?
Transthoracic echocardiography
ECG Chest X ray (LVH)
Cardiac catheterisation
Cardiac MRI
What is the treatment for Aortic stenosis?
The primary treatment of symptomatic AS
Asymptomatic patients with severe AS who have an LVEF <50% or who are undergoing other cardiac surgery.
AVR may be considered in asymptomatic patients with very severe AS or severe AS with rapid progression, an abnormal exercise test, or elevated serum B-type natriuretic peptide (BNP) levels
Balloon aortic valvuloplasty
Antihypertensive
ACE inhibitors
Statins
What happens in Aortic regurgitation?
Aortic regurgitation (AR) is the diastolic leakage of blood from the aorta into the left ventricle.
It occurs due to incompetence of valve leaflets resulting from either intrinsic valve disease or dilation of the aortic root
What are the two types of Aortic regurgitation?
It can be chronic culminate into congestive cardiac failure
It can be acute medical emergency, presenting with sudden onset of pulmonary oedema and hypotension or cardiogenic shock
What are the risk factors for Aortic regurgitation?
Rheumatic heart disease Infective endocarditis Aortic valve stenosis Congenital heart defects Congenital bicuspid valves
What are the causes of Aortic regurgitation?
Marfan’s Syndrome Connective tissue disease/collagen vascular diseases idiopathic Ankylosing spondilytis Traumatic
What is the cause of Acute Aortic regurgitation?
Infective endocarditis can lead to rupture of leaflets/ paraventricular leaks.
Vegetation on valvular cusps can cause inadequate leaflets closure.
Chest Trauma can cause a tear in the ascending aorta.
What is the cause of Chronic Aortic regurgitation?
Bicuspid Aortic Valve.
Rheumatic Fever - fibrotic changes causing thickening & retraction of leaflets.
What is the Pathophysiology of Acute Aortic regurgitation?
Increase blood volume in LV during systoleLV end diastolic pressure increases increase in pulmonary venous pressure dyspnea and pulmonary oedemaheart failure cardiogenic shock
What is the Pathophysiology of Chronic Aortic regurgitation?
gradually increase in LV volumeLV enlargement and eccentric hypertrophy
Early stages Ejection fraction normal or slightly increase after some time Ejection fraction falls and LV end systolic volume rises
Eventually LV dyspnoea lower coronary perfusion ischaemia, necrosis and apoptosis
What are the presentations for Aortic Regurgitation?
Acute AR Cardiogenic shock Tachycardia Cyanosis Pulmonary edema Austin flint murmur Chronic AR Wide pulse pressure Corrigan (wate hammer pulse) Pistol shot pulse (Traube sign)
What investigations can be done to diagnose Aortic regurgitation?
Transthoracic echocardiography
Chest X ray
Cardiac catheterisation
Cardiac MRI/CT Scan
What is the management for Aortic regurgitation?
Management (Aortic Valve replacement)
Acute ARIonotropes/vasodilators & valve replacememt & repair
Chronic asymptomaticIf LV function is normal can be managed by drugs or reassurance
Chronic symptomatic–) First line is valve replacement with adjunct vasodilator therapy
Prevention:
Prevention is key: Treat Rheumatic fever and infective endocarditis.
What happens in Mitral stenosis?
Obstruction to left ventricular inflow at the level of mitral valve due to structural abnormality of the mitral valve
Leads to pulmonary Hypertension & right heart failure.
What are the causes of Mitral stenosis?
Rheumatic fever Carcinoid syndrome Use of ergot/serotonergic drugs SLE Mitral annular calcification due to aging Amyloidosis Rheumatoid arthritis Whipple disease Congenital deformity of the valve
What is the pathophysiology of Mitral stenosis?
Typically occurs decades after an episode of rheumatic fever, acute insult leads to the formation of multiple foci and infiltrates the endo and myocardium along the valves walls, these get calcified, thickened & contracted.
What does Mitral stenosis cause?
Initially moderate exercise or tachycardia result in exertional dyspnoea due to increased left atrial pressure
Severe mitral stenosis leads to increase in left atrial pressure , transudation of fluid into the lung interstitium leading to dyspnoea at rest or exertion
Pulmonary hypertension may develop as the result of it
The restricted orifice limits filling of left ventricle limiting cardiac output
Hemoptysis if bronchial vein rupture
What is the presentation for Mitral stenosis?
H/0 of Rheumatic fever Dyspnoea orthopnoea Diastolic murmur Loud P2 Neck vein distention Hemoptysis 40-50 years age
What are the investigations required to diagnose mitral stenosis?
ECG Transthoracic echocardiography Chest X ray Cardiac catheterisation Cardiac MRI/CT Scan
What is the management for mitral stenosis?
Progressive asymptomatic No therapy required
Severe asymptomatic no therapy generally required adjuvant balloon valvotomy
Severe symptomatic diuretic, balloon valvotomy, valve replacement & repair adjunct b blockers
What happens in Mitral regurgitation?
Abnormal reversal of blood flow from the left ventricle to the left atrium.
It is the most frequent valvular heart disease
It is caused by the disruption in any part of the mitral valve apparatus
What are the Acute causes of Mitral regurgitation?
Mitral valve prolapse Rheumatic heart disease Infective endocarditis Following valvular surgery Prosthetic mitral valve dysfunction
What are the Chronic causes of Mitral regurgiataion?
Rheumatic heart disease SLE Scleroderma Hypertrophic cardiomyopathy Drug related
What happens in Chronic Mitral Regurgitation?
progression leads to eccentric hypertrophy leading to elongation of myocardial fibres and increased left end diastolic volume Increase in preload & a decrease in afterload increase in end- diastolic volume and a decrease in end-systolic volume
Eventually prolonged volume overload leads to left ventricular dysfunction and increased left ventricular end-systolic diameter
How does Infective endocarditis lead to Mitral regurgitation?
Abscess formation, vegetations, rupture of chordae tendineae and leaflet perforation
What is the presentation for Mitral regurgitation?
Dyspnea diminished S1, murmur high
Fatigue pitched, blowing xx
Orthopnea
Chest pain
Atrial fibrillation
What are the investigations you can do for Mitral regurgitation?
ECG Transthoracic echocardiography Chest X ray Cardiac catheterisation Cardiac MRI/CT Scan
What is the treatment for Mitral regurgitation?
Acute MR Emergency Surgery & preoperative diuretics & intra-aortic balloon counterpulsation
Chronic asymptomatic 1st ACE inhibitors
Beta blockers if left ventricular ejection fraction is less than 60% 1st line is surgery
Chronic symptomatic1st surgery plus medical treatment
If left ventricular ejection fraction is less than 30% 1st line is Intra-aortic balloon counterpulsation
