1b Structural Heart Disease Flashcards
Which side of the heart is the bicuspid (mitral) valve on?
Left side
Which side of the heart is the tricuspid valve on?
The right side
What is equation for cardiac output?
stroke volume x heart rate
What is the equation for mean arterial pressure and pulse pressure?
MAP = DBP + 1/3PP
PP = SBP - DBP
MAP = 2 X DBP + SBP/3
What is the equation for stroke volume and ejection fraction?
SV = EDV - ESV
Ejection Fraction = SV / EDV x 100
What do structural heart diseases cover?
Number of defects which affect the valves and chambers of the heart
What is aortic stenosis?
Stenosis means that valve is tight and not very flexible, and when the blood rushes through it during systole it has to gush through a tight opening
What murmur do you get with aortic stenosis?
Ejection systolic murmur
What is patent ductus arteriosus?
hole in the heart:PDA occurs when the opening between the aorta and pulmonary artery does not close as it should. so there is mixing of blood and free flow of blood between lungs, aorta and pulmonary artery.
What murmur do you get with patent ductus arteriosus?
Continuous murmur
Name of the muscular ridges located in the atria of the heart
Pectinate Muscles
Cord like tendons that connect papillary muscles to valve
Chordae tendinae
Irregular muscle columns that project from inner surface of ventricles
Trabeculae carneae
Small cone shaped muscles located in the ventricles of the heart
Papillary muscles
What are some examples of congenital heart diseases?
Atrial Septum defects
Ventricular septem defects
Coarctation of Aorta
Tetralogy of Fallot
Patent ductus arteriosus
Which are the examples of Structural Heart Disease which develops later in life?
Due to valvular dysfunction - Atrial Stenosis / regurgitation or muscular (cardiomyopathies)
Describe the pathology which occurs in Atrial and Ventricular Septum Defects?
Holes between either ventricles or atria - separates left and right
therefore, there is mixing of the blood which is oxygenated and deoxygenated
Left = under higher pressure so when right blood enters into left = results in overload and hypertension leading to right sided heart failure
What are the four problems in Tetralogy of Fallot?
- Over riding aorta
- Right ventricular hypertrophy
- Ventricular septum defects
- Pulmonary Valve Stenosis
What is coarctation of the aorta?
When the wall of the aorta bends in on itself and becomes constricted, reducing stroke volume and cardiac output resulting in breathlessness
What are the four types of valvular defects?
Aortic Stenosis / Regurgitation
Mitral Stenosis / Regurgitation
Can you get pulmonary / tricuspid defects?
Yes but they are significantly more uncommon
What two things indicate aortic stenosis?
Early peaking, systolic ejection murmur - confirmed through echo
What type of murmur will be present in patient with Aortic Stenosis?
Ejection systolic murmur (≥3/6 is present with a crescendo-decrescendo pattern that peaks in mid-systole and radiates to the carotid)
What preceeds aortic stenosis?
aortic sclerosis - aortic valve thickening without flow limitation
What are the risk factors associated with Aortic Stenosis?
Hypertension
High LDL
Smoking
CRP
CKD
Radtiotherapy
What are the causes of Aortic Stenosis?
Rheumatic Heart Disease
Congenital Heart Disease
Calcium Build Up
Why is a murmur present in aortic stenosis?
When there is blood which is force flowing against calcified wall results in a murmur
What happens to the valvular endocardium/valve endothelium in aortic stenosis?
(DEGENRATION OR CONGENITAL MALFORMED VALVES)
Wear & tear of the valve or disruption of valve endothelium
(UNTREATED GROUP A STREPTOCOCCUS)
Anti-Strep antibodies wrongly attack valves leading to inflammation of valve endocardium
What is the result of damage to valvular endothelium or endocardium
Fibrosis and calcification of aortic valve
What does acute aortic regurgitation present as?
medical emergency - sudden onset pulmonary oedema and hypotension or cardiogenic shock
How does fibrosis and calcification lead to pulmonary congestion in aortic stenosis?
-Disrupted blood flow through the aortic valve
-Left ventricle has to pump harder to get blood through stenotic valve
-Continuous forceful contractions cause myocardial hypertrophy
-Hypertrophic ventricle becomes stiff overtime and harder to fill leading to decreased cardiac output and diastolic dysfunction
-pressure overload in LV causes left atrium to dilate leading to increased pressure in lungs causing pulmonary conhgestioj
Clinical findings in aortic stenosis
Ejection Systolic murmur
Syncope on exertion
Angina on exertion
Diffuse crackles in lungs and dyspnoea
What causes Ejection systolic murmur in aortic stenosis?
Disrupted blood flow through the valve during systole
What causes syncope in aortic stenosis?
During exercise heart can’t contract efficiently leading to decrease output to brain
What causes angina (chest pain) in aortic stenosis?
Hypertrophied muscle-high oxygen demand
Increase in pressure in ventricles as compared to aorta resulting in less coronary perfusion
What causes lungs crackling and dyspnoea in aortic stenosis?
Increase back pressure in lungs leading to pulmonary congestion
Other Obs/ lab findings/history in aortic stenosis?
History of Rheumatic fever, High lipoprotein, high LDL, CKD, age >65
What four investigations should be done for a patient with suspected Aortic Stenosis?
Doppler echo
What is the primary treatment of symptomatic AS?
Aortic Valve Replacement
How might treatment of severe AS differ?
Transcatheter valve replacement as opposed to surgical
Surgical valve prosthesis
What is Aortic regurgitation?
The diastolic leakage of blood from the aorta into the left ventricle
occuring due to incompetence of valve leaflets resulting from either intrinsic valve disease or dilation of the aortic root
What murmur is present in aortic regurgitation?
Diastolic murmur
What does acute vs chronic aortic regurgitation present as?
ACUTE
medical emergency - sudden onset pulmonary oedema and hypotension or cardiogenic shock
CHRONIC
Culminate into congestive cardiac failure
What are the congenital causes of Aortic Regurgitation?
RDH
Infective endocarditis
Aortic valve stenosis
Congenital Heart defects
Congenital Bicuspid valves
What are the causes of Aortic regurgitation due to aortic root dilation?
Marfans Syndrome
Connective Tissue Disease
Trauma
Idiopathic
Ankylosing spondylitis
How does AR lead to heart failure and congestion?
Valve closes poorly when pressure higher in aorta thean LV
Blood flow back to LV causing increase in pressure and volume
Acute dilation causes increase in SV however if chronic causes muscles to hypertrophy
This weakens the myocardium and inability contract properly causing systolic heart failure
Back pressure in LV to atria and ultimately lung vasculature leads to congestion
Clinical findingd of AR with explanation
Diastolic murmur - blood flowing backwards
S3 gallop sound in early diastole - LV dialate leads to early filling of heart during diastole
Angina on exertion and fatigue - Hypertrophied muscle has high oxygen demand but with the low aortic pressure, coronary ciculation is compromised and less blood flow to the body
Diffuse crackles, dyspnoea, orthopnoea - Back pressure on lungs leading to pulmonary congestion
Which two signs are distinctive of Chronic Aortic regurgitation?
Wide pulse pressure
Corrigan (water hammer pulse)
What are the presentations of Acute Aortic Regurgitation?
Cardiogenic shock
Tachycardia
Cyanosis
Pulmonary edema
Diastolic murmur
What is the management plan for Acute AR?
Aortic Valve replacement
What is the management plan for chronic asymptomatic AR?
Vasodilator therapy improves haemodynamic and delays the need for aortic valve replacement/repair (AVR) in asymptomatic patients with chronic severe AR.
How can AR be prevented?
Treat rheumatic fever and infective endocarditis
What is mitral Stenosis?
Obstruction to left ventricular inflow at the level of mitral valve due to structural abnormality of the mitral valve
Can lead to pulmonary hypertension and right heart failure
What murmur is present in mitral stenosis?
Mid-diastolic rumble
What is the main cause of Mitral Stenosis?
Rheumatic Fever
How does inflammation lead to obstruction in mitral stenosis?
Recurrent inflammation leads to fibrous deposition and calcification
Chordae tendineae thickening and shortening
Leads to obstructed blood flow
How does obstruction lead to heart failure and congestion in mitral stenosis?
Impaired filling in left atrium and ventricle
Increase in left atrial pressure leads to back pressure to lung causing congestion
Decreased filling leads to decreased stroke volume and cardiac output causing congestive heart failure
Increase in right ventricle pressure leads to hypertrophy of right ventricle –right sided heart failure
Clinical findings in mitral stenosis and reason
Afibrillation - Left artrial enlargement stretches conduction fibres
Dysphagia & hoarseness - Left atrial enlargement compresses surrounding structures
Cardiogenic shock/congestive heart failure - Decrease in stroke volume and cardiac output
Right sided heart failure - hypertrophy of right ventricle
Dyspnoea - Increase pulmonary pressure leads to pulmonary oedema
What might a patient with Mitral Stenosis present with?
H/0 of Rheumatic fever
Dyspnoea
Mid Diastolic murmur
Loud S1 opening snap in early stages
Dysphagia
Atrial fibrillation
Haemoptysis
What extra investigation might you conduct on a patient with suspected Mitral Stenosis?
ECG
Chest X ray
Transthoracic echocardiography
What is the treatment plan for progressive/severe asymptomatic Mitral Stenosis?
No therapy required, sometimes might do adjuvant balloon valvotomy with severe
What is the treatment plan for severe symptomatic Mitral Stenosis?
Diuretic, balloon valvotomy, valve replacement, repair adjunct, B Blockers
What is mitral regurgitation?
Abnormal reversal of blood flow from the left ventricle to the left atrium.
What murmur is present in mitral regurgitation?
Holosystolic/systolic murmur
What are the causes of acute mitral regurgitation?
RDH
Infective endocarditis
Mitrl Valve Prolapse
Following Valvular surgery
Prosthetic mitral valve dysfunction
What are the causes of chronic Mitral Regurgitation?
RHD
SLE
Scleroderma
Hypertrophic cardiomyopathy
Drug related
How does Mitral Regurgitation occur?
Back flow of blood to atrium
Increased volume and pressure in atrium
Increased volume pushed back to ventricle in next diastole
LV dilation decreases systolic function
Decreased stroke volume and cardiac output causing congestive heart failure
Bacl pressure to lungs leads to congestion
Clinical findings with Mitral Regurgitation?
Holosystolic murmur - blood consistently backwards in systole
S3 heart sound -Increase volume pushed back into
left ventricle
Increased serum creatinine - Decreased oxygen to kidneys due to to decrease in organ perfusion - parenchymal damage
Congestive heart failure - decrease in stroke volume and cardiac output
Peripheral oedema - congestive heart failure
Decrease in oxygen sat, tachypnoea, wheeze, crackles and frothy sputum - Fluid extravasates out of vessels and into the lungs
What might someone with Mitral Regurgitation present with?
Dyspnoea
Holosystolic murmur
S3 heart sound
Signs of congestive heart failure
Investigations for mitral regurgitation
Transthoracic echocardiography
ECG
Chest X ray
Cardiac MRI/CT Scan
What is the treatment plan for acute severe MR?
Regurgitation can be corrected by repairing or replacing the supporting valve structures. A prosthetic ring can be inserted to reshape the valve.
What is the treatment plan for Chronic Asymptomatic MR?
Watchful waiting or surgery
What is the treatment plan for Chronic Symptomatic MR?
1st surgery plus medical treatment32
What is a cardiomyopathy?
Cardiomyopathy is a disease of the heart muscle that makes it harder for heart to pump blood to rest of your body
What are the three types of cardiomyopathies?
Dilated
Hypertrophic
Restrictive
What is Dilated cardiomyopathy characterised by?
Dilated cardiomyopathy is characterized by ventricular chamber enlargement and systolic dysfunction with normal left ventricular wall thickness.
Most commonly occurs in 3rd and 4th decade. Progressive, usually irreversible, dysfunction
Causes of dilated cardiomyopathy
FAMILIAL
Idiopathic
SECONDARY
Myocardial ischemia/heart valve disease
After childbirth
Thyroid disease
Myocarditis
Alcoholism
Autoimmune disorders
Ingestion of drugs
Inherited disorders
How does damage&death of myocytes lead to congestive heart failure in dilated cardiomyopathies?
Eccentric fibrosis and volume increases
Enlargement of LV without increase to myocardial mass
Frank starling law initially - contractility is ok
Gradually over distension and systolic dysfunction
Decrease cardiac output, volume overload leads to congestive heart failure
History and presentation of dilated cardiomyopathy?
Dyspnoea and cold extremities - low cardiac output leads to insufficient tissue oxygenation
Displaced apex beat - Enlarged left ventricle
Fatigue - Low cardiac output and decreased organ perfusion
Angina- low coronary perfusion
Pulmonary congestion - diffuse crackles
Peripheral oedema - heart failure
Sundden cardiac death
What investigations should you do for someone with dilated CM?
Genetic Testing
Viral serology
ECG
Chest X ray
Cardiac catheterisation
Cardiac MRI/CT Scan
Exercise stress test
Echocardiography
What is the management of Dilated CM?
Counselling
Consider causes
Teatment and rehabilitation
Diet modification - fluid and sodium restriction
Treatment of underlying disease
Symptoms of heart failure - ACEi B-blockers, diurectics or ARBs, consider surgical LVAD
Treat arrhythmias - Amiodarone
Thrombotic events - Anticoagulants
What is Hypertrophic Cardiomyopathy?
Genetic
It is defined by an increase in left ventricular wall thickness that is not solely explained by abnormal loading conditions.
How does pathophysiology of hypertrophic cardiomyopathy lead to sudden cardiac death?
Thickening and disarray of left ventricular myocardium
Frequently involves intraventricukar septum which results in obstruction of flow through the left ventricular outflow tract
Disorganised myocytes disrupt signal conduction
Ventricular arrhythmias
Sudden cardiac death
What is the presentation of a patient with hypertrophic cardiomyopathy?
S4 - forceful atrial contraction into hypertrophied left ventricle
Syncope - decreased cardiac output
Fatigue - Low cardiac output, decreased organ perfusion
Pulmonary congestion & oedema - Diffuse crackles
Systolic murmur- Due to passage of blood through narrow outflow tract
Sudden cardiac death
Management of hypertrophic cardiomyopathy
HCM with Symptoms
Beta blockers –If contraindicated B=Verapamil
If refractory and drugs fail Mechanical Therapy with Pacemaker or Surgery (septal myectomy or ablation)
What is the diagnosis of Restrictive cardiomyopathy based on?
Establishing the presence of a restrictive ventricular filling pattern
What is restrictive CM characterised by?
Characterised by deposition of abnormal substances within heart tissue
What causes decreased cardiac output in restrictive cardiomyopathies?
Infiltration causes endomyocardial fibrosis leading to the ventricular walls stiffening, leading to diastolic dysfunction.
Atrial enlargement occurs due to impaired ventricular filling during diastole, but the volume and wall thickness of the ventricles are usually normal.
Restrictive physiology predominates in the early stages, causing conduction abnormalities and diastolic heart failure
Reduced ventricular filling leads to decreased cardiac output
What might someone with restrictive CM uniquely present with?
Ascites & pitting oedema in peripheries - Increase venous pressure leads to right sided heart failure
Hepatomegaly - hepatic congestion due to right heart failure
S4 Heart sounds - atrium contarcts into stiff ventricle
Increase in jugular venous pressure - due to right heart failure
Easy bruising, weight loss - heart failure
What investigations should be conducted for someone with suspected Restrictive CM?
CBC, Serology, Amyloidosis check, Chest Xray ,ECG ,Echocardiography, Catheterisation, MRI/Biopsy
How is Restrictive Cardiomyopathy treated>
Heart Failure Medication
Immunosuppression - steroids
Pacemaker
Antiarrhythmic Therapy
Cardiac transplantation
Why and what heart failure medication in managing restrictive cardiomyopathy?
Guideline-directed medical therapy for heart failure, including angiotensin-converting enzyme inhibitors or angiotensin receptor II blockers, diuretics and aldosterone inhibitors should be initiated in patients with reduced LV
