Flashcards in Valvular Heart Diseases Deck (57)
What causes rheumatic fever?
Immunologic response to acute streptococcal pharyngitis, Cross-reacivity between streptococcal antigen and structural glycoprotein. Leads to chronic rheumatic valvular heart disease
Criteria for diagnosis of Rheumatic Fever
Joints - migrating polyarthritis
Nodules - subcutaneous nodules in flexor compartment
E- Erythema marginatum (rash with advancing edge and clearing center)
Minor criteria include migratory arthralgia, fever, increased APR, and prolonged PR interval
Signs of streptococcal infection
Antistreptolysin O antibodies, positive throat culture
Treatment of Rheumatic Fever
Treatment of complications
Prevention of Rheumatic Fever
What is mitral stenosis
Obstruction of LV inflow that prevents proper filling during diastole.
Normal Mitral valve area and area in stenosis?
4-6 cm normal
less than 2 is stenosis
Common causes of mitral stenosis
Rheumatic heart disease is most common
What happens in the heart during mitral stenosis
Normally there is no pressure difference between the LA and LV, but with mitral stenosis, LA is higher pressure. LV pressures are normal, but because there is reduced filling, SV and CO may decrease.
Symptoms of mitral valve stenosis
Congestion and dyspnea because elevated pressures of LA will cause fluid to back up in the lungs. Also hemoptysis
What does the severity of MS depend on
Degree of reduction in valve area.
MS heart sounds
Loud S1 best heard at apex (occurs because high pressure difference in LA and LV keeps leaflets far apart).
Opening Snap - Follows S2. Sound of the stenotic leaflets snapping open. Followed by diastolic rumble of blood rushing past stenotic leaflets (decrescendo). Best heard at apex. Best heard with the patient lying on the left side in expiration.
Sounds like lub-butter
How does mitral stenosis cause afib?
Dilated LA messes up conduction system.
How to treat MS medically?
Medical therapy doesn't prevent progression. Can give B blockers, ca channel blockers, digoxin to control HR and prolong diastole for improved filling. Can also give diuretics with fluid overload.
Surgery for MS?
Percutaneous balloon mitral valvuloplasty.
Causes of mitral regurgiation
Rheumatic heart disease, infective endocarditis, degeneration. Dilation/calcification of annulus. Problems with the chordae tendinae (break), CAD involvement of papillary muscle.
What happens in the heart with mitral regurgitation?
A portion of the LV stroke volume is ejected back into the LA. Therefore SV decreases, LA will dilate, hypertrophy of the LV because normal venous return plus regurgitated blood comes into it during diastole.
Does LV SV increase with MR?
Yes, because preload increases.
Hemodynamic profile of MR?
Tall LA V wave because blood rushes back into atria during systole.
Normal LA size and compliance so regurgitation causes increased pressure. This backs up and causes congestion.
Dilated LA, so pressure doesn't elevate much. Normal LA and pulmonary venous pressures, but decrease in CO because blood will regurgitate into low-pressure LA. So fatigue weakness ensue. Eccentric hypertrophy occurs.
Mitral regurgitation heart sounds
Holosystolic murmur (between S1 and S2). Chronic sounds like "wow-duh." S3 frequently present in acute.
How can you increase the murmur from mitral regurgitation?
Breathe out, squeeze hands, squat. This is how you distinguish from aortic stenosis.
How to manage acute MR?
Reduce afterload, which will increase CO and decrease regurg. Diuretics. Emergency surgery.
How to manage chronic MR
Vasodilators (for HTN). Mitral valve repair.
How to check if mitral regurgitation is occurring?
Use echo, can see using cardiac cath. Look for cardiomegaly on chest CR.
Etiology of mitral valve prolapse
Can be familial, or associated with marfans/other connective disorder.
What happens with mitral valve prolapse?
Valvular leaflets enlarge and prolapse into LA during systole.
Symptoms of MP?
Generally asymptomatic, but can cause chest pain or palpitations sometimes.