Valvular heart disease Flashcards
Common heart valve lesions
Mitral stenosis,
Mitral regurgitation,
Aortic stenosis,
Aortic regurgitation
Symptoms of mitral stenosis
haemoptysis, Chest pain, Cough, Hoarse voice (rare), Infective endocarditis
Mitral stenosis pathophysiology
MV orifice < 2cm^2,
Always chronic,
LA pressure increases,
= Pulmonary hypertension,
= Right heart dilatation
Mitral stenosis signs
Mitral facies (red/purple cheeks), Normal pulse, JVP - prominent a-wave, Tapping apex beat, Diastolic thrill, RV heave, Diastolic murmur, Pulmonary oedema
Investigations for mitral stenosis
+ findings
ECG
CXR
Echo: Thickening and scarring of leaflets Cardiac MRI
Cardiac catheterisation: Large pressure gradient between LA and LV
FINDINGS:
RV Hypertrophy
LA enlargement/dilatation
Mitral stenosis treatment
Valvotomy (balloon/surgical),
Mitral valve replacement
Mitral regurgitation symptoms
ACUTE: dyspnoea, pulmonary oedema, cardiogenic shock
CHRONIC: Fatigue, right heart failure, dyspnoea/ palpitations (due to AFib)
Mitral regurgitation signs
Normal/reduced pulse,
JVP - prominent if RH failure,
Brisk + hyperdynamic apex beat
RV heave,
Systolic “blowing” murmur - loud at apex, radiating to axilla.
Mitral regurgitation investigations
+ likely findings
ECG
CXR
Echo: Dysfunction of leaflets, papillary muscles, chordae tendineae etc.
FINDINGS:
LA enlargement
RVH
Calcification of mitral annulus
Mitral regurgitation treatment
Mitral valve apparatus repair,
Mitral valve replacement
General symptoms of heart valve disease
Fatigue,
Dyspnoea,
Oedema
Mitral regurgitation pathophysiology
ACUTE: ↓ End systolic pressure and end systolic volume = ↓ LV wall tension.
CHRONIC: ↓BP = ↑ EDV = normal ESV + LV hypertrophy
Orifice size depends on:
Preload, afterload and LV contractility
Aortic stenosis pathophysiology
Aortic valve narrowing
↑LV systolic pressure = LV hypertrophy = ↑ LV myocardial O2 demand = ischaemia
Aortic stenosis symptoms
Long asymptomatic phase
Angina,
Syncope,
Exertional dyspnoea,
Aortic stenosis signs
Pulse - small volume and slowly rising, JVP - prominent if RH failure, Low BP, Vigorous and sustained apex beat, RV heave, Late peaking systolic murmur, radiating to carotids
Aortic stenosis investigations + likely outcomes
ECG: ST changes (show LV strain)
CXR: Calcification of aortic valve
Echo: Low AV cusp mobility
Cardiac catheterisation: High pressure gradient btw LV and aorta
FINDINGS:
LV Hypertrophy
Aortic stenosis treatment
Medical treatment: Limited to those who develop heart failure,
Interventional treatment: Aortic valve replacement or repair
Aortic regurgitation pathophysiology
↓diastolic BP = ↑EDV = LV hypertrophy and dilatation
= ↑ LV myocardial O2 demand = ischaemia
Aortic regurgitation symptoms
CHRONIC:
Long asymptomatic phase,
Exertional dyspnoea
ACUTE:
Poorly tolerated as wall tension cannot acutely adapt
Aortic regurgitation signs
Pulse - large volume and collapsing
Wide pulse pressure,
Hyperdynamic, misplaced apex beat
Early diastolic, soft murmur
Aortic regurgitation investigations + likely findings
ECG: ST changes (LV strain)
CXR
Echo: Regurgitant flow, Thickening/prolapsing/no. of AV cusps
Cardiac MRI
FINDINGS
LV Hypertrophy/ dilatation
Cardiomegaly (chronic)
Aortic regurgitation treatment
Only valve disease that can use drug therapy:
Vasodilator therapy
Interventional treatment: Aortic valve replacement or repair
potential sternotomy complications
Wire infection, Painful wires, Sternal dehiscence (splitting open), Sternal malunion (fails to heal), Cardiac tamponade (fluid in pericardial sac), Stroke, Death
Common valve problems requiring cardiac surgery
Senile tricuspid aortic stenosis,
Bicuspid aortic stenosis
Degenerative mitral regurgitation
Indications for valve replacement
AS: severe
AR: severe, especially with LV dilatation
MS: orifice <1.5cm2 (audible murmur)
MR: severe = systolic blood flow reversal in pulmonary veins.
Types of prosthetic valves
+ results
Biological (e.g. pig) - wears out after 15 years
Mechanical (plastic) - lasts > 40 years, warfarin required for life
Treatment of infective endocarditis of valves
Medical = antibiotics (much more successful if native valve compared to prosthetic)
Surgery of severe or persistent
Use and results of mitral valve repair
Used in degenerative MR,
complete valve competence can be restored = better than valve replacement
Symptoms of infective endocarditis
Fever/ Chills Night sweats, fatigue, malaise, weight loss Weakness Arthralgia (joint pain) Headache Dyspnoea
Signs of infective endocarditis
Cardiac murmur Janeway lesions Osler nodes Splinter haemorrhages Petechial haemorrhage Roth spots vasculitic rash
Investigation of infective endocarditis
Blood culture: Identify causative bacteria
FBC: Elevated acute inflammatory markers (ESR/ CRP)
ECG: Prolonged PR interval
Echocardiogram: Shows vegetations, damaged valves, turbulent flow etc.
Urinalysis: Haematuria (blood in urine)
Treatment of infective endocarditis
Prolonged antibiotics
Surgery (if severe regurgitation, large vegetations, persistent pyrexia or progressive renal failure)
Rheumatic heart disease symptoms
Symptoms of heart valve disease/ IE
Signs of rheumatic heart disease
Pericardial friction rub
Murmurs
Pancarditis
Rheumatic heart disease investigations
Blood culture: show previous strep infection
FBC: Increased inflammatory markers
Erythrocyte Sedimentation Rate (ESR): Shows clotting if increased
ECG: features of heart block
Treatment of rheumatic heart disease
Anti-inflammatories
Antibiotics
Treatment of heart valve disease/ IE
Surgery if unresolved by medical treatment
Prevention = Prolonged antibiotics to prevent recurrent streptococcal infections
Sternotomy
Most common thoracic incision
Used for:
- heart valve replacements
- cardiac transplant
- CABG
Prevention of IE for high risk groups
E.g. previous IE, prosthetic valve, congenital heart disease
Prophylactic antibiotics before dental procedures Strict dental and cutaneous hygiene Disinfection of wounds Discourage piercing/ tattooing Limit invasive procedure
Contraction of endocarditis
Mitral valve prolapse
Congenital heart disease (e.g. bicuspid aortic valve)
Prosthetic valves
Rheumatic heart disease
^ Damaged/diseased valves cause turbulent blood flow leading to endothelial damage
- -> formation of NBTE
- -> bacteria in bloodstream (due to infected needle, open wound etc.) adhere to NBTE
- -> vegetation
Rheumatic heart disease pathophysiology
Strep infection causes immune system to make Abs that attack the endocardium (type II hypersensitivity reaction)
= repeated inflammation of heart valves with fibrinous repair
