Valvular Disorders Flashcards
What is acute rheumatic fever? What organisms cause it and who does it affect? What process causes it?
Systemic complication of pharyngitis due to group A beta hemolytic streptococci. Affects children 2 - 3 weeks after an episode of streptococcal pharyngitis. Caused by molecular mimicry; bacterial M protein resembles proteins in human tissue
How is acute rheumatic fever diagnosed?
Based on Jones crtiteria
What are the components of the major criteria for diagnosing acute rheumatic fever?
- Migratory polyarthritis
- Pancarditis
- Subcutaneous nodules
- Erythema marginatum
- Syndeham chorea
Which structure is involved in Endocarditis in Jones criteria?
Mitral valve is more commonly involved than aortic valve. Characterized by small vegetations along lines of closure that lead to regurgitation
How is acute rheumatic fever diagnosed?
Based on Jones crtiteria with evidence of prior groud A beta-hemolytic streptococcal infecition (elevated ASO or anti-DNAse B titers) with the presence of major and minor criteria
Which structure is involved in Endocarditis in Jones criteria?
Mitral valve is more commonly involved than aortic valve. Characterized by small vegetations along lines of closure that lead to regurgitation
What is myocarditis characterized by in Jones criteria? What is the most common cause of death during the acute phase?
With Aschoff bodies that are characterized by foci of chronic inflammation, reactive histiocytes with slender wavy nuclei (Anitschkow cells), giant cells, and fibrinoid material. Myocarditis
What types of pancarditis are involved in the Jones criteria?
Endocarditis, Myocarditis, Pericarditis (leads to friction rub and pleuritis)
What does chronic rheumatic heart disease cause? Which structures are involved?
Results in stenosis with a classic ‘fish mouth ‘ appearance. Almost always involves the mitral valve, leads to thickening of chordae tendinae and cusps. Occassionally involve
What does chronic rheumatic heart disease cause? Which structures are involved? What are the complications it causes?
Results in stenosis with a classic ‘fish mouth ‘ appearance. Almost always involves the mitral valve, leads to thickening of chordae tendinae and cusps. Occassionally involves the aortic valve. Leads to fusion of the commissures. Complications include infectious endocarditis.
What is aortic stenosis? When does it present and what causes it?
Narrowing of the aortic valve orifice. Usually due to fibrosis and calcification from wear and tear. May also arise as a consequence of chronic rheumatic valve disease. Presents in late adulthood (> 60 years).
What is the difference between stenosis due to wear and tear and that of rheumatic disease?
Rheumatic disease has coexisting mitral stenosis and fusion of the aortic valve commissures.
What is heard on auscultation for aortic stenosis? What causes this presentation?
Cardac compensation leads to a prolonged asymptomatic stage during which a systolic ejection click is followed by a crescendo-descrescendo murmur.
What are the three complications of aortic stenosis? How is it treated?
- Concentric left ventricular hypertrophy 2. Angina and syncope with exercise 3. Microangiopathic hemolytic anemia (schistocytes). Valve replacement after onset of complications.
What is aortic regurgitation? What causes it? How is it treated?
Backflow of blood from the aorta into the left ventricle during diastole. Arises due to aortic root dilation (e.g. syphilitc aneurysm and aortic dissection or valve damage. Most common cause is isolated root dilation. Treatment is valve replacement once LV dysfunction develops.
