Lectures 13-15: Valvular Heart Disesae Flashcards
Acute rheumatic fever is a consequence of…When are symptoms? Primary organs?
Immune-mediated consequence of group A beta-hemolytic streptococcal pharyngitis; 2-3 weeks after pharyngitis; heart, skin and connective tissue
Where is acute rheumatic fever prevalent?
Highly prevalent in developing countries
What is the mechanism of acute rheumatic fever (protein)?
Autoimmune cross-reactivity b/t bacterial antigens and normal tissue (M protein)
Signs/symptoms of acute rheumatic fever (3)
Migratory polyarthralgias, Syndenham’s chorea, erythema marginatum
Acute rheumatic fever: heart (2 main points)
Pancarditis (can effect any layer) and mitral regurgitation from valvulitis
Acute rheumatic fever: pathology
Aschoff Body: granulomatous lesions w/ a fibroid center and perimeter of immune cells (acutely, eventually develops into fibrosis)
JONES
J = joints, O = heart (myocarditis), N = subcutaneous nodules, E = erythema marginatum, S = Sydenham chorea
To get diagnosis of acute rheumatic fever, you must have…
Evidence of strep and later manifestations
Treat acute episode with…
Antibiotics (penicillin) + anti-inflammatory therapy (aspirin)
Secondary prevention…(tx)
IV penicillin every 4 weeks for at least 5 years
What is the LT heart consequence of rheumatic fever?
Mitral stenosis = decades later, permanent deformity/impairment of valves
What does a stenotic mitral valve do to the left atrium?
Enlarge due to pressure/volume overload
Describe the hemodynamic profile of mitral stenosis
Left atrial pressure elevated and there is a pressure gradient b/t left atrium and left ventricle during diastole
Consequences of enlarged L atrium (4)
Pulmonary venous congestion –> heart failure; atrial fibrillation –> palpitations; atrial fibrillation –> cerebrovascular accident; impinged recurrent laryngeal –> Hoarseness (Ortner syndrome)
Mitral stenosis: exam findings (2)
Diastolic murmur and opening snap (OS)
Internval between S2 and OS relates _______ to severity of MS
Inversely
Mitral stenosis: ECG findings (2)
P Mitrale: extended, bihumped P wave in Lead II; Atrial fibrillation
Mitral stenosis: medical treatment (2)
- Anticoagulation (even if absence of a fib); 2. Rate control (beta-blockers or the like to increase time for ventricle filling)
Does medical therapy of mitral stenosis slow progression?
No, but helps with symptoms
When would a patient qualify for percutaneous balloon mitral valvuloplasty (PMBV)? What is the second option to PMBV?
Symptomatic patients or those with a fib/pulmonary hypertension; mitral valve replacement
SO: PMBV for ________ patients
Symptomatic
T/F: People with normal valves are at risk for infective endocarditis
False: normal valves are resistant
Risk factors for infective endocarditis (3)
- Turbulent blood flow across abnormal, diseased valve; 2. Lesions provoked by electrodes/catheters; 3. Repeated IV injections of solid particles in IV drug users
Pathology of infective endocarditis
Vegetation: platelets, fibrin, microorganisms
Most common micro-organism to cause infective endocarditis. Second most common? How do you differentiate?
Staph; strep; staph = catalase positive; staph aureus = coagulase positive
Catalase positive, coagulase positive?
Staph aureus
Catalase positive, coagulase negative?
Another staph, likely staph epidermidis
IV drug use, most common micro-organism
Staph aureus
Prosthetic valve endocarditis, most common micro-organism
Staph epidermidis
Underlying colon malignancy, most common micro-organism
Strep bovis
Subacute bacterial endocarditis following dental work, most common micro-organism
Viridan sreptococci
Culture negative, most common micro-organisms (mnemonic = 5 + one)
HACEK (Hemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella); Coxiella (Q fever)
Duke criteria is used to diagnose
Endocarditis
Clinical manifestations of endocarditis: 2 sets of phenomenom
Vascular/embolic phenomenon: pieces of vegetation break off and travel; Immunologic phenomenon: deposition of circulating immune complexes
Is infective endocarditis associated with heart murmurs?
Yes: you can get a new or worsened heart murmur
What is a splinter hemorrhage? What phenomenon is it related to?
Black hemorrhage under nail –> skin finding of infective endocarditis; embolic phenomenon
Eye finding of infective endocarditis. What phenomenon is it related to?
Roth Spot; embolic phenomenon
Oslar nodes: What phenomenon is it related to?
Immunologic phenomenon
Role of ECHO in endocarditis
Diagnostic: to find vegetation
Infective endocarditis: treatment
Extended course of antibiotics (4+ weeks), consider methicillin-resistant if staph is suspected (vancomycin)
If someone is not getting better, you do ________ for their endocarditis. Why else? (2)
Surgery; immune involvement, very large vegetation
Etiology of aortic stenosis (three most common causes in order of prevalence)
- Calcification of normal valve (7th, 8th decade); 2. Calcification of bicuspid valve (6th decade); 3. Rheumatic disease
Pathogenesis of aortic stenosis
Risk factors (bicuspid valve, smoking, dyslipidemia) –> aortic sclerosis (inflammation) –> aortic stenosis (calcification)
Bicuspid arotic valve (%, 2 most common sequalaes and 2 associations )
Common –> 1 - 2 % of people; aortic stenosis is most common sequalae followed by aortic regurgitation; associated w/ other abnormalities: coarctation of aorta and thoracic aortic aneurysm
What kills patients with BAV?
Thoracic aortic aneurysm
Pathophysiology of aortic stenosis
Gradient b/t LV and aorta during systole –> murmur
Three symptoms of aortic stenosis and impact on median survival
- Angina (5 years); 2. Syncope (3 years); 3. HF (2 years)
Why does HF occur in aortic stenosis?
Contractile dysfunction develops because of insurmountably high afterload
What is the murmur in aortic stenosis?
Coarse crescendo-decrescendo (diamond shaped) late-peaking systolic murmur
Describe pulses in aortic stenosis
Weakened (parvus) and delayed (tardus) upstroke of the carotid artery
A valve area of less than…is what?
1.0 cm2 = severe aortic stenosis
Treatment for aortic stenosis..
No proven medical therapy
What is the preferred treatment for symptomatic severe aortic stenosis?
Surgical aortic valve replacement
Indication for aortic valve replacement
SYMPTOMS
Define aortic regurgitation
Incomplete closure of the aortic valve in diastole resulting in retrograde flow from the aorta back into the LV (in diastole)
Mechanisms of aortic regurgitation (6, 2 categories)
Abnormalities of valve leaflets: Bicuspid valve, infective endocarditis, rhematic heart disease; Dilation of aortic root: age/hypertension-related, aortic aneurysm (CT disease), aortic dissection
Describe problem found in Marfan syndrome
Medial necrosis of aorta –> dilation of proximal ascending aorta –> aortic dissection AND mitral valve prolapse from dilation of mitral valve
What gene is defective in Marfan?
Fibrillin
Hemodynamic profile of aortic regurgiation
Aortic pressure falls rapidly during diastole with a wide pulse pressure (difference b/t systolic and diastolic blood pressure)
Heart sound in aortic regurgitation
Blowing murmur in early diastole: low-frequency, mid-diastolic rumble, decrescendo
Findings in chronic aortic regurgitation vs acute aortic regurgitation
Chronic: enlarged LV that has decreased pressure to LA; Acute: sudden shock of elevated pressure to LA –> pulmonary congestion
Symptoms (3) and signs (3) of aortic regurgitation
Symptoms: exertional dyspnea, fatigue, uncomfortable sensation of forceful heart beat; Signs: widened pulse pressure, blowing murmur, Austin-Flint murmur
Austin-Flint Murmur: describe and what does this cause?
Downward displacement (closure) of the anterior leaflet of the mitral valve during diastole by the regurgitant stream of aortic regurgitation; functional cause of mitral stenosis
Physical findings in aortic regurgitation (3, but don’t memorize this stuff)
- Bisferiens pulse (double systolic impulse in carotid or brachial artery); 2. Quincke sign (capillary pulsations visible at proximal nail bed); 3. Bounding carotides
Dicrotic notch is normal/abnormal. What is it?
Normal; rebound effect from arterial elasticity after systolic filling
Who gets aortic regurgitation treatment? What is the treatment?
Medical therapy does not slow progression, but symptomatic patients may benefit from valve replacement
Mitral regurgiation has two large categories. What are these?
Primary cause: structural defect of valve component; Secondary cause: valve is structurally normal but regurgitation results from LV enlargement
Mitral regurgitation and acuity
If it’s acute, you have dilated high pressure LA –> pulmonary edema; chronically, LA is accommodating and it has dilated
Hemodynamic profile of mitral regurgitation
Tall v wave (atrial filling) due to back-flow from ventricle
What is the most common cause of mitral regurgiation
Myxomatous degeneration: extra mitral valve tissue
What are the typical symptoms of mitral regurgitation? Why?
Dyspnea, orthopnea, PND = pulmonary edema
Murmur of mitral regugitation
Apical holosystolic murmur that often radiates to axilla
What does holosystolic mean?
All of systole = starts at S1 and extends to S2
Define mitral valve prolapse. What is it frequently accompanied by?
Abnormal billowing of a portion of one or both mitral leaflets into the left atrium during ventricular systole; mitral regurgitation
Does mitral valve prolapse always affect patients?
Nope: often regurge is minimal and it doesn’t cause symptoms
Causes of mitral valve prolapse?
Familian, or accompanyting CT diseases (Marfan)
What is the classic exam finding of mitral valve prolapse?
Midsystolic click (tensing chordae tendinae as leaflet billows into LA)
Mitral regurgitation treatment (acute, chronic primary, chronic secondary)
Acute MR: surgery; Chronic primary MR: surgery for symptomatic patients = mitral valve repair (not replacement); Chronic secondary MR: medical therapy
What is the medical therapy for acute MR?
Afterload reduction
Two types of valves and key points
Mechanical: requires LT consistent anticoagulation; Bioprosthetic: less durable –> 50% failure in 15 years
