8/14- Valvular Heart Disease 2 Flashcards
How to calculate total mitral stroke volume in mitral insufficiency?
SV = Forward (aortic) + regurgitant (mitral)
(then % regurgitation = regurg/total)
Mitral insufficiency causes what type of murmur (diastolic or systolic)?
Systolic
- Pansystolic murmur that coincides with leak across MV
What causes acute mitral insufficiency?
Associated with what?
Caused by: injury to or dysfunction of any valvular component
Often associated with acute heart failure
Broad course in chronic mitral insufficiency?
When does heart failure occur?
- Pathology and insufficiency progress slowly over many years
- Allows for gradual enlargement of the atrium and ventricle
- Heart failure occurs very late
What are the components of the mitral valve?
- Leaflets
- Chordae tendinae (attach to:)
- Papillary muscles
What are the pathologic causes of mitral insufficiency?
Muscular (normal leaflets):
- Acute MI/infarction
- Trauma
Connective tissue:
- Chordal rupture (Marfan’s, prolapse)
- Annular disruption or dilation due to LV dilation (CHF)
Leaflets
- Perforation, vegetations (endocarditis)
- Prolapse (myxomatous degeneration)
- Post inflammatory scarring (rheumatic)
Steps of mitral valve prolapse?
- Valve tissue degenerates
- Leaflets sag into atrium during systole (prolapse), separate from coaptation line: mild MR
- Chordae elongate, fracture, leaflet fragment becomes flail: severe MR
What is myxomatous degeneration?
Aka prolapse aka Barlow’s syndrome
Redundant leaflets cause what kind of murmur?
Mid-to-late systolic murmur
Mitral valve prolapse results in what heart sounds?
- Mid systolic click
- Mid-late systolic murmur
- If severe, holosystolic murmur, S2
How is mitral valve prolapse affected by dynamic auscultation?
MVP results in a systolic murmur at apex
- Louder and longer murmur with maneuvers that decrease EDV or increase systolic function (standing, Valsalva)
- Later and softer murmurs when LVEDV is increased (squat and leg elevation)
Which condition responds like mitral valve prolapse in dynamic auscultation (increase in murmur with Valsalva/standing)?
Hypertrophic cardiomyopathy with dynamic LVOT obstruction
How can HCM and MVP be differentiated (since they return the same dynamic auscultation results)?
Hand grip exercise and the presence of click:
- HCM murmur will become softer
- MVP murmur will become louder
What is the pathophysiology of acute mitral insufficiency?
Sudden LV to LA leak -> acute LV volume overload
- LA and pulmonary venous pressures rise acutely
- Normal size LV
Early short systolic murmur and S3
- Soft S1
- LA pressures rise sharply, equaling LV systolic, terminating murmur
Pathophysiology of chronic mitral insufficiency?
Chronic LV to LA leak -> gradual LV volume overload
- Eccentric LVH with large LV, large LA
Holosystolic murmur and S3 gallop
- Holo (or pan)systolic murmur coincides with actual leak from LV to LA that starts with S1 and ends with S2