Mitral Stenosis, Mitral Regurgitation, Aortic Valve Stenosis, Aortic Valve Regurgitation (pathology) Flashcards
What is mitral stenosis?
Mitral valve orifice <2cm^2
What is the pathophysiology of mitral stenosis (5)?
- ↑ AV pressure
- ↑ LA pressure
- Pulmonary hypertension
- ↑ TPR
- Right Heart dilatation + tricuspid & pulmonary regurgitation
What are the symptoms of mitral stenosis (6)?
- SOB due to pulmonary oedema
- Haemoptysis due to thin-walled veins rapture
- Left atrium and atrial appendage enlargement leading to systemic emboli
- Infective endocarditis
- Chest pain
- Hoarseness due to compression of recurrent laryngeal nerve by enlarged LA
What are the signs of mitral stenosis (7)?
- Mitral facies (purple discoloration of cheeks and nose)
- Normal pulse
- Prominent JVP
- Tapping apex beat
- Diastolic thrill
- Right ventricle heave
- Diastolic murmur – opening snap-> ↑ pressure gradient LA-LV
What are the investigations for Mitral stenosis? (What can be seen from these investigations?)
ECG - Signs of right ventricular hypertrophy - Taller R waves in V1 V2 - LA enlargement P > 0.12 sec Cardiac catheterisation – determine LA pressure indirectly CXR - Left atrium enlargement -> straight left heart border Echo - Thickening + scarring of leaflets - Fusion of commissures - ‘elbowing’ of anterior leaflet - Velocity of transmitted flow at rest & exercise-> determine severity of MS MRI - Enlarged LA
What is the medical treatment for mitral stenosis?
- Diuretics + restrict salt
- Restore sinus rhythm in AF
- Anticoagulation-> stroke prevention
What is the surgical treatment for mitral stenosis?
- Valvotomy
- Mitral valve replacement if MVA on echo < 1.5 cm2
What is the difference between a biological and mechanical valve replacement? How does the follow up treatment differ?
Biological valve= no warfarin but worn-out valve after 15 years –ELDERLY
Mechanical valve= warfarin for life, valve lasts > 40 years – YOUNG
What is mitral regurgitation?
Leaky valve
Annular enlargement—> ↑ regurgitant volume—> LV compensation
What is acute vs chronic Mitral regurgitation?
Acute= heart contracts more forcefully= ↓ESV and ↑ESP Chronic= ↑EDV, normal ESV , ↑↑ contractility= LEFT VENTRICULAR HYPERTROPHY
What is the aetiology of mitral regurgitation (4)?
- Rheumatic heart disease
- Mitral valve prolapse – Myxomatous degeneration
- Infective endocarditis
- Functional mitral regurgitation due to enlarged LV and annular dilatation
What are the causes of acute mitral regurgitation (2)?
Valve perforation
Chordal/papillary muscle rupture
What are the symptoms of acute mitral regurgitation?
EMERGENCY!
- SOB due to pulmonary oedema and Cardiogenic shock
- decreased BP & very high Heart rate
What are the symptoms of chronic mitral regurgitation (3)?
- Fatigue, exhaustion due to ↓CO
- Right heart failure
- SOB or palpitations due to AFib
What are the signs of mitral regurgitation (7)?
- Normal pulse or reduced in HF
- Prominent JVP if RH failure
- Brisk and hyperdynamic apex beat
- RV heave (abnormally large beating heart)
- Reduced S1 because valve leaflets cannot find each other
- Holosystolic murmur of MR- radiates to axilla
- Split S2: early A2, loud P2
What investigations for mitral regurgitation? (What would they show)
ECG
- Left Atrial enlargement P> 0.12 sec
- Right ventricular hypertrophy tall R waves in V1 V2
CXR
- Cardiomegaly, LA enlargement, mitral annulus calcification
Transoesophageal echo
- Assess LV dimensions
- Identify causes of MR (leaflet dysfunction, rapture of chordae/papillary muscles
- Assess disease severity with Pulmonary arterial pressure-> prognostic indicator
MRI
- Accurate cardiac volumes
- Volumetric determination of regurgitant volume
What is the medical treatment for acute mitral regurgitation?
Acute MR - Reduce preload / afterload • SODIUM NITROPRUSSIDE – vasodilator • DOBUTAMINE ↑↑contractility • Intra-aortic balloon pump = ↑↑CO
What is the medical treatment for chronic mitral regurgitation?
- No therapy helps with haemodynamic
- Preserve LV functio
What are the surgical treatments for mitral regurgitation?
- Mitral valve repair or replacement
- Repair> replacement
- Replacement if severe MVR with blood flow into pulmonary v. on echo
What is aortic valve stenosis?
Normal AV area= 3-4 cm2
AV Stenosis < 1.5-2 cm2
Rheumatic vs degenerative aortic valve stenosis?
Rheumatic:
- Fusion of commissures and retraction/stiffening of free cusp margins
Degenerative:
- Due to atherosclerosis, slow inflammatory process, calcification of cusps
What is the pathophysiology of aortic valve stenosis?
↑↑ LV systolic pressure -> LV hypertrophy -> ↑↑ Left ventricular end diastolic pressure ↑↑ LA pressure
Pulmonary hypertension
↑↑ myocardial O2 use -> ischemia-> LV failure
What is the aetiology of aortic valve stenosis?
- Degenerative Most common
- Rheumatic
- Bicuspid AV – congenital abnormality- 2 leaflets instead of 3
What are the symptoms of aortic valve stenosis?
- Long asymptomatic phase
- Severe symptoms
• Angina
• Syncope/dizziness due to ↓ CO
• SOB on exertion
• HF
What are the signs of aortic valve stenosis (7)?
- Small volume pulse- slowly rising
- JVP if RHF
- Low BP
- Vigorous sustained apex beat
- RV heave
- End systolic murmur-radiate to carotids
- normal S1 + less audible A2 because of murmur (differentiate from aortic sclerosis)
What are the investigations for aortic valve stenosis?
Echo - Demonstrate AV cusp mobility - LV function and hypertrophy - Doppler =determine velocity of blood ejected from LV into aorta—> indirectly determine AV area Cardiac MRI
What are the medical and surgical treatments for aortic valve stenosis?
Medical
- Limited to those that develop HF
Surgical
- Aortic valve repair or replacement
What is aortic valve regurgitation?
LV receives systolic volume + regurgitant volume —> ↑↑ LV EDV and LV systolic pressure —> LV hypertrophy + dilatation —> ↑↑ myocardial O2 use—> ischaemia—> LV failure
What is the aetiology of aortic valve regurgitation?
Can be due to defect in: - Aorta • Dilated aorta (Marfan’s, hypertension) - Leaflets: • Bicuspid aortic valve • Rheumatic heart disease • Endocarditis • Myxomatous degeneration
What are the symptoms of acute and chronic aortic valve regurgitation?
Acute AR – EMERGENCY - ↑↑ wall tension Chronic AR - Long asymptomatic phase - Exertional breathlessness
What are the signs of aortic valve regurgitation?
- Large volume collapsing pulse – CORRIGAN SIGN
- Wide pulse pressure ↑↑ systolic ↓diastolic
- hyperdynamic displaced apex beat
- Early diastolic murmur – difficult to hear- ask patient to lean forward
What are the investigations for aortic valve regurgitation? (What would they show?
ECG
- ST changes due to LV strain, left axis deviation due to left ventricle hypertrophy
CXR
- Cardiomegaly in chronic AR
*Cardiac catheterisation- obsolete
Echo
- AV cusp anatomy
- LV function, dilatation, and hypertrophy
- Doppler assessment of regurgitant flow = ↑↑ pressure difference between systole and diastole= ↑↑ severity
MRI
What are the medical and surgical therapies for aortic valve regurgitation?
Medical
- Vasodilator therapy
Surgical
- AV repair (rare) or replacement in severe AV regurgitation with LV dilatation