Mitral Valve Prolapse Flashcards
Pathophysiology of MVP
- Collagen dissolution causes myxomatous degeneration, deposition of mycopolysaccharides in middle spongiosa layer of mitral valve leaftlet
- Stretching of degenerated leaflets and chordae tendinae leading to MVP
- MVP causes excessive stress of papillary muscles, leading to dysfunction and ischaemia
- Rupture of chordae tendineae and progressive annular dilatation and calcification worsens mitral regurgitation <-> vicious cycle of stress and injury
How do patients with MVP present (symptoms) ?
Occurs most frequently 15-30 years old, women > men
- Asymptomatic
- Symptomatic
- Palpitations, chest pain, anxiety, lightheadedness - Complications
- Congestive cardiac failure: fatigue, dyspnoea
- Infective endocarditis
- Arrhythmias
- Thromboembolism - Sudden death
What causes mid-systolic click?
(relates to name of MVP)
Inability of papillary muscles or chordae tendinea to tether mitral valves in late stages of systole.
Prolapse of valve leaflet into LA and sudden tensing of mitral valve apparatus
What are the causes and diseases associated with MVP? (11)
- Myxomatous degeneration of mitral valve tissue - may also affect tricuspid and aortic valves
- ASD (ostium secundum) 20%
- Cardiomyopathy
- Myocarditis
- Marfan’s syndrome
- Ehlers Danlos syndrome
- Osteogenesis imperfecta
- Polycystic kidney disease
- SLE
- Pseudoxanthoma elasticum
Rarely
11. Rheumatic fever
12. Ischaemic heart disease
What are the auscultatory findings of MVP?
- Mid systolic click
- Due to tensing of MV apparatus when prolapsed into LA
- Accentuated closer to S1 with standing, straining (Valsalva)
- Diminished closer to S2 with squatting, isometric exercises, beta blockers - Late systolic murmur, high pitch, crescendo-decresendo
- Loudest at LLSE
- Occasionally “whooping” or “honking” - Radiation depends on leaflet
- Posterior prolapse - jet anteriorly - > to base of heart
- Anterior prolapse - jet posteriorly -> axilla and back
What are the manoeuvers that accentuate findings of MVP?
- Valsalva manoeuver
- Standing
Earlier systolic click, longer duration of systolic murmur
- Decreases preload - > reduced cardiac volume which further impairs papillary muscles/chordae tendinae from maintaining tension on leaflet
–> prolapse of leaflet into LA
What are the features associated with MVP? (5)
Features of Marfan Syndrome
1. Thoracic skeletal deformity
2. Inguinal hernia
3. Joint dislocations
4. Meniscal tears
5. Easy bruising
Progression of MVP
- MR with left atrial dilatation resulting in:
1A. Atrial fibrillation
1B. Pulmonary hypertension - Ventricular atopy
- Autonomic dysfunction - resting bradycardia, postural hypotension
Differential diagnoses of MVP murmurs and how to differentiate them?
- Aortic stenosis - ESM, upper sternal edge
- Pulmonarty stenosis - short ESM louder on inspiration, diminishes with Valsalva
- HOCM - diminishes with squatting, intensifies with standing and Valsalva
- MR - short murmur +/- PSM, no click
How common is MVP?
- Prevalence in the general population
- Gender distribution
5-10% of population
Commonly in females (female > male 3:1)
How would you investigate MVP?
ECG - usually normal
- Premature ventricular contractions
- TWI in inferior leads
TTE with colour flow or wave Doppler
- Confirm diagnosis
- Complications of MR, MR jet
- EF resting and exercise to assess functional capacity
TEE if accurate anatomical information required for intraoperative guidance during valve repair
How would you manage a patient with mitral valve prolapse with or without complications?
- Education
- Reassurance if asymptomatic
- Endocarditis prophylaxis in those with MR
- Treat arrhythmias and palpitations - beta blockers
- Treat chest pain
- Treat complications of MR - CCF, IE, AF, TIA
- Surgical indications as MR
- Mitral valve repair preferred over replacement
Endocarditis prophylaxis is required for MVP with __
Those with __ but without __ do not require prophylaxis
Required - Audible click or murmur
Not required - TTE positive MVP without murmur
Reversible MVP occurs when __ is relatively small in comparison to enlarged mitral annulus/leaftlet/chordae tendinae
This usually occurs in:
1. __ who is __ or __
2. Sudden __ in __
Left ventricle
- Healthy women, dehyration or pregnant
- Sudden weight gain in anorexic patient
What are the complications of mitral valve prolapse? (5)
- Thromboembolism - stroke
- Chordal rupture
- Endocarditis
- Arrhythmias - AF, SVT, VT, prolonged QTc
- Progression to mitral regurgitation
- Sudden death
- Cardiac neurosis