3.3.2. Cardiac Pathology Part 2: Valvular, Endocarditis, Cardiomyopathy and Tumors Flashcards
What is acute rheumatic fever? What causes it?
Systemic complication of pharyngitis due to group A Beta Hemolytic streptococci
When does Rheumatic fever usually hit? Who does it target?
Children 2-3 weeks after strep throat
What biological process is at work causing rheumatic fever?
Molecular mimicry.
Bacterial M protein resembles human tissues, so when you launch an attack to the bacterial m proteins, you start attacking yourself as well
To Diagnose Rheumatic Fever you use ____ ____.
Jones Criteria
Describe Jones Criteria
- Evidence of prior group A Beta Hemolytic strep infection (ASO or anti DNase B Titer, both markers for this)
- Minor Criteria (fever, elevated ESR)
- Major Criteria
What are the major Jones Criteria?
Joint problems (migratory polyarthritis to large joints)
O is shaped like a heart…heart issues
Nodules in the skin (subcutaneous)
Erythema Marginatum - Annulus rash that appears redder at the margins
S Corea - Involuntary movement
Key major problem with Jones Criteria
The heart issues
What is pancarditis?
Key heart issue with Rheumatic fever that involves inflammation of all three heart layers
Describe the endocarditis portion of the pancarditis we see in Rheumatic Fever
We get vegetation in the enflamed endocardium that look like little nodules at the mitral valve. Aortic valve may or may not be affected as well, Mitral always.
What can the endocarditis cause in the heart?
Due to affecting the mitral valve it can call mitral valve regurgitation
What do we see in the myocardium during pancarditis?
Aschoff bodies - granulomatous structures consisting of fibrinoid change, lymphocytic infiltration, occasional plasma cells, and characteristically abnormal macrophages surrounding necrotic centres.
Some of these macrophages may fuse to form multinucleated giant cells.
Others may become Anitschkow cells or “caterpillar cells”, so named because of the wavy appearing nuclei
Most common cause of death in rheumatic fever?
The myocarditis part. So if you see Aschoff and Anitschow, be worried.
What issues do we see with the pericarditis portion of the pancarditis in Rheumatic Fever?
Friction rub
Discuss the timeline of Rheumatic fever a bit
Acute phase resolves but can progress to chronic disease.
Repeat exposure to group A Beta hemolytic streptococci results in relapse.
Can lead to rheumatic valvular disease
Rheumatic valvular disease
Valve scarring that results from a bunch of acute attacksfrom Rheumatic fever
Result of rheumatic valvular disease
Stenosis, almost always of mitral valve. Due to thickening of the chordae tendinae and cusps
When involving the aortic valve, leads to fusion of commissures
Complication of Rheumatic valvular disease
endocarditis
What is aortic stenosis? Size change?
Narrowing of the aortic valve orifice
Becomes less than 1cm squared from 3-4
What usually causes aortic stenosis?
Fibrosis and calcification from wear and tear
When does aortic stenosis present? What further complicates it?
Late adulthood, older than 60
Bicuspid Aortic valve increases risks and hastens disease onset
How can we distinguish whether the stenosis in the aorta is from wear and tear or rheumatic valvular disease?
- With RVD, the mitral stenosis must be present always
2. Aortic valve will have fused commisures, not seen in wear and tear
Compensation by the LV in aortic stenosis leads to a ____ ____ stage.
Prolonged asymptomatic
Auditory sounds with an aortic stenosis and why?
Systolic ejection click due to the blood breaking through the stenosis followed by a crescendo-decrescendo murmur caused by the blood rushing out
Complications of aortic stenosis
- Concentric Left ventricular hypertrophy
- Angina and Syncope with exercise
- Microangiopathic hemolytic anemia
What is Microangiopathic hemolytic anemia?
When blood rushes past a calcified stenosis, you can cut the RBCs up, causing cell death
Treatment for aortic stenosis
Valve replace but only after symptoms begin
What is aortic regurgitation? What causes it?
Backflow of blood from the aorta into the LV during diastole
Arises due to aortic root dilation, like with a syphilitc aneurysm or valve damage like in infectious endocarditis
Clinical findings for aortic regurgitation
- Early blowing diastolic murmur caused by blood going backwards
- Bounding pulses, pulsating nail bed and head bobbing (hyperdynamic circulation)
Discuss the pressure changes involved with aortic regurgitation
Systolic pressure goes up and diastolic falls casuing a widening (increase) in your pulse pressure which gives you the bounding pulses/hyperdynamic circulation
Clinical features of aortic regurgitation
LV dilation and eccentric hypertrophy (one aspect of the ventricle, not the whole thing. We see this with volume issues in the ventricle)
Treatment of aortic regurgitation
Valve replacement when LV dysfunction develops
What is mitral valve prolapse?
Myxoid degeneration of the valve to cause the valve to become weaker/floppy.
LV pushes back towards the valve and balloons it back during systole (causes a click)
Clinical findings for mitral valve prolapse
Mid Systolic click followed by regurgitation murmur
Treatment for mitral valve prolapse
Valve replacement
Complications of mitral valve prolapse
Infectious Endocarditis
Arrhythmia
Severe mitral regurgitation
But these are all rare
What is mitral regurgitation?
Reflux of blood from LV to LA during systole. Many causes.
Clinical findings for mitral regurgitation
Holosystolic “blowing” murmur
Louder with squatting and expiration
Results in volume overload and left sided heart failure
Clinical features of mitral stenosis?
Opening snap followed by a diastolic murmur
Bad results due to mitral stenois
Volume overload leading to dilation of the LA Causes: - Pulmonary congestion - Pulmonary HTN - Atrial fibrillation
What is endocarditis
Inflammation of the endocardium, in particular the surface of valves
Usual cause of endocarditis?
Bacterial infection
Most common bacteria in endocarditis? What does it target and present as?
S viridans
Targets previously damaged valves (low virulence organism)
Results in small vegetations that do not destroy the valve
How does bacteria get caught in the valve?
Previously damaged valve leads to thrombosis for healing, which traps the bacteria i nthe thrombotic vegetations
Describe the high virulence bacteria associated with endocarditis
S Aureus
Most common cause in IV drug abuse
Affects normal valves, particularly the tricuspid
Results in large vegetations that destroy the valve ( = acute endocarditis)
When do we see S epidermidis?
Affects patients with prosthetic valves
When do we see S Bovis?
Endocarditis in patients with underlying colorectal carcinoma
What are HACEK organisms and why do we care about them? List them out.
Hemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella
Negative blood cultures
Clinical featurs of endocarditis
Fever Murmur Janeway lesions Olser Nodes Anemia of Chronic Disease
What are Janeway lesions? Osler nodes? What causes them?
Vegetations on the valves can be shot off into circulation, leading to septic emboli of these bacterial clumps.
Patients will present with red lesions on the palms and soles (Janeway Lesions) or painful lesions on fingers and toes (Osler nodes)
Lab findings for endocarditis
- Typically positive blood cultures
- Anemia of chronic disease
- Trans Esophageal Echo (TEE) can be used to see
What is nonbacterial thrombotic endocarditis
Sterile vegetations that arise with hypercoagulable state or underlying adenocarcinoma
What is Libman Sacks Endocarditis? What does it lead to?
Sterile vegetations associated with SLE
Presents on both surfaces of the mitral valve
Results in mitral regurg
What is dilated cardiomyopathy? Result?
Dilation of all chambers in the heart
Causes systolic dysfunction due to incredible stretching
Complications of dilated cardiomyopathy
Causes biventricuar CHF with mitral and tricuspid valve regurgitation and arrhythmia
Most common causes of dilated cardiomyopathy?
- Genetic mutations
- Myocarditis
- Alcohol abuse
- Drugs
- pregnancy
General idiopathic, i.e., we don’t know
Most common cause of myocarditis
coxsakie virus
Treatment for dilated cardiomyopathy?
Heart replacement
What is hyertrophic cardiomyopathy? Cause?
Massive hypertrophy of the left ventricle due to genetic mutations in sarcomere protins in an Autosomal Dominant condition
Clinical findings of Hypertrophic ardiomyopathy
- Decreased CO
- Sudden death due to Ventricular arrhythmia
- Syncope with exercise
Biopsy of hypertrophic cardiomyopathy?
Myofiber hypertrophy with disarray - cells going in all directions, not together in the same direction like usual
Explain restrictive cardiomyopathy
Decreased compliance of ventricular endomyocardium that restricts filling during diastole
Causes of restrictive cardiomyopathy
- myloidosis
- Sarcoidosis - granulomas get in there
- hematochromatosis - iron deposition
- Endocardial fibroelastosis in kids - Dense layer of fibrous tissue in the endocardium, so you can’t stretch the ventricle during filling
- Loeffler syndrome - eosinophilic infiltrate in the heart leading to fibrosis of the endocardium AND myocardium
Presentation of restrictive cardiomyopathy.
Presents as CHF
Low voltage EKG with diminished QRS amplitudes
Myxoma tumor?
Benign mesenchymal proliferation with a gelatinous appearence
Histology of a myxoma?
Abundant ground substance on histology
The most primary cardiac tumor in adults
Myxoma
Why is the myxoma of the mesenchyme and not the myocyte?
Myocytes are permanent and established in adults so theres no real chance for cells to proliferate to make a tumor
Effects and location of myxoma
Usually a pedunculated mass in the left atrium that can cause syncope due to obstruction of the mitral valve
Rhabdomyoma
Benign hemartoma in cardiac muscle
Most common primary cardiac tumor in children?
Rhabdomyoma
Rhabdomyoma is associated with what?
Tuberous sclerosis
Where do rhabdomyomas usually arise?
Venticle
Common metastases of the heart include what? Where do they go specifically?
Lung cancer
Breast cancer
Melanoma
Lymphoma
Usually go to the pericardium resulting in pericardial effusion,
