Lecture 3: Cardiac Pathology Part 2 (Hillard) Flashcards
What is the most common cause of arrythmias?
Ischemic Heart Disease
- also caused by cardiomyopathies, myocarditis, valvular disease, congenital disorders
almost ANY structural change can cause an arrhythmia
What is Sick Sinus Syndrome and Atrial Fibrillation?
SSS: SA node damage causing bradycardia
- AV node takes over –> < 50-60 BPM
AF: myocytes depolarize independently and sporadically w/variable transmission in AV node (can be seen with atrial dilation)
- irregular HR = atrial fibrillation
- can cause thrombus formation/thromboembolism
What is Heart Block and what is the difference between first, second, and third degree?
- dysfunctional AV node
First Degree: prolonged PR interval
Second Degree: intermittent transmission
Third Degree: complete failure
Hereditary Channelopathies
What is Long QT Syndrome?
What is the classical presentation of disease?
- due to hereditary abnormal ion channels which cause arrhythmogenic disease (K+ LOF/Na+ GOF)
- Long QT is most common form
- cause of SUDDEN DEATH after EXERTION
Classic Pt: strong swimmer that drowns due to arrhythmia
- shows Torsades de Pointes on ECG
What is Hypertensive Heart Disease?
What can it lead to the development of and what is another organ finding common in patients with disease?
- left ventricular hypertrophy (typically concentric, > 500 grams) with clinical history or evidence of hypertension in other organs (myocytes are larger and thicker)
- diastolic dysfunction leading to left atrial enlargement –> atrial fibrillation (can cause CHF or Sudden Cardiac Death)
look for granular kidneys with hyaline atherosclerosis
What is Cor Pulmonale?
- isolated Right-sided Pulmonary hypertensive heart disease in the setting of Pulmonary Hypertension
- can arise due to disease of pulmonary parenchyma, vessels, or disorders of chest movements; also large pulmonary embolus
Left Heart Failure is MOST common cause of Right-sided Heart Failure
What is Calcific Aortic Stenosis?
What are three common conditions it is associated with? (H/H/I)
- MOST COMMON VALVULAR ABNORMALITY (inc. risk with age - 60-80 yo)
- due to “wear and tear” associated with chronic HTN, hyperlipidemia, and inflammation
- see mounded calcifications in CUSPS that prevent complete opening of valve
What is a Bicuspid Aortic Valve?
What is a complication that is frequently found with this disease?
- a congenital condition that shows accelerated course of aortic stenosis (shows symptoms 1-2 decades earlier)
- can become incompetent leading to valve dilation and prolapse
- bacterial endocarditis is commonly seen with this condition
How does Calcific Aortic Stenosis commonly present?
- leads to inc. LV pressure and concentric LV hypertrophy (muscle becomes ischemic –> angina)
signs: systolic murmur, angina (die within 5 yrs), syncope (die within 3 yrs), and CHF (die within 2 yrs) - treat with SURGICAL REPLACEMENT
What is Mitral Annular Calcification?
Who is it commonly seen in?
- calcific deposits in fibrous annulus (base of leaflets) of mitral valve that is usually asymptomatic
- can lead to regurgitation, stenosis, arrhythmias with deep calcifications; acts as nidus for thrombus and infective endocarditis
- commonly seen in WOMEN > 60 yo
What is Mitral Valve Prolapse?
What genetic disease is it commonly seen in?
What do the leaflets look like in this disease?
- valve prolapse back into left atrium during systole (“floppy valve”) –> more common in WOMEN
- can be seen in MARFAN SYNDROME; also MI and rheumatic fever
- leaflets are thick and rubbery (Myxomatous Degeneration due to inc. proteoglycan deposits) and “hooding” (interchordal ballooning)
How does Mitral Valve Prolapse present clinically?
- most asymptomatic with mid-systolic CLICK and is the most common cause of mitral regurgitation in developed countries; chronic can cause dyspnea
- can cause (rare): infective endocarditis, mitral insufficiency, arrhythmias (atrial), and thromboembolism
What is Rheumatic Fever and what is used to confirm diagnosis?
- multisystem inflammatory disorder following GROUP A STREP pharyngitis (“SCARLET FEVER”)
- typically occurs 10 days-6 wks AFTER infection
- cannot culture active infection from blood
- caused by Abs and CD4+ T cell rxn against M Streptococcal Ag that causes rxn to heart/joint/skin/soft tissue/nervous system antigens (MIMICRY)
Confirm: Abs to STREPTOLYSIN O and DNase B
What are 6 common signs of Acute Rheumatic Fever? (F/MP/P/SN/EM/SC)
- Fever (101 F+)
- migratory polyarthritis (large joints)
- pancarditis
- subQ nodules
- erythema marginatum (curved, ring-shaped macules)
- Sydenham Chorea (basal ganglia damage)
- hopping, halting gait, grimacing, asymmetric jerking
What are 4 common heart findings in pts. with Acute Rheumatic Fever? (P/VV/MP/AB)
What valves does Rheumatic Heart Disease affect?
- pericarditis (fibrinous), myocarditis, endocarditis
- verrucae formation (valvulitis w/vegetations)
- MacCallum Plaques
- irregular thickening in Left Atrium due to regurg.
Histo: Aschoff Bodies w/Anitschkow cells
- PATHOMNEUMONIC
affects: mitral > aortic > tricuspid valves
- mitral valves have “fish mouth”/”buttonhole” stenosis
How does Chronic Rheumatic Heart Disease present?
- valvular leaflet thickening, short chordae tendinae, fusion, and regurg. –> VALVULAR STENOSIS causing DIASTOLIC “rumbling” MURMUR
- structural changes predisposes valve to infective endocarditis
- can cause left atrial enlargement –> atrial fibrillation and thromboembolic events
What are the most likely causes of infective endocarditis in patients with:
- native, structurally abnormal valves
- poor dentition/invasive dental procedures
- prosthetic valves
- IV drug use
- Streptococcus viridans
- HACEK organisms
- Staph epidermidis
- Stap. aureus
- causes RIGHT-SIDED endocarditis if injected
most infective endocarditis is LEF-SIDED
What are the HACEK organisms associated with infective endocarditis in patients with poor dentition?
H - hemophilus A - actinobacillus C - cardiobacterium E - eikenella K - kingella
What are 4 physical findings of infective endocarditis?
What are they all caused by?
- Subungal Splinter Hemorrhages
- Janeway Lesions (spots on palms/soles)
- Osler Nodes (tender nodules w/pale center)
- Roth Spots (retinal hemorrhage)
all are caused by small septic emboli that flake off of left-sided endocarditis
What are 4 common causes of Nonbacterial Thrombotic Endocarditis? (S/C/AS/SLE)
- sepsis, cancer (procoagulant release), antiphospholipid syndrome (APS), and systemic lupus erythematous (LIBMAN-SACKS ENDOCARDITIS)
- all cause sterile, non-inflammatory valvular thrombi and are asymptomatic until embolization occurs
What are Antiphospholipid Syndrome and Libman-Sacks Endocarditis?
APS: autoantibodies to endothelial membrane (ANTICARDIOLIPIN, lupus anticoagulant)
- manifests as fetal loss during pregnancy
- can also be associated with lupus
LSE: endocarditis caused by systemic lupus
- nonbacterial
What is Carcinoid Heart Disease?
What side of the heart does it occur on and what are common signs of disease?
- bioactive compounds (SEROTONIN) from carcinoid tumors induce plaque-like endocardial/valvular thickening
- lesions are usually seen during massive metastatic liver burden and ONLY on RIGHT-SIDE of heart (lung vasculature degrades the mediators)
Signs: flushing, diarrhea, dermatitis, bronchoconstriction
What is the difference between use of Mechanical Prosthetic valves and Tissue Prosthetic valves?
M: usually long lasting (>25 yrs)
- inc. risk of thromboembolism
- pts. on life-long anticoagulant therapy
T: made from cow or pig valves
- inc. risk of mechanical failure (usually 10-15 yrs)
- only on anticoagulants for 1st 3-6 months
both types have INCREASED risk of infective endocarditis
What conditions are associated with:
- crescendo-decrescendo systolic murmurs
- holosystolic murmurs (2)
- diastolic decrescendo murmur
- diastolic rumbling murmur
- continuous “machine-like” murmur
- calcific aortic stenosis
- mitral regurgitation and VSD
- aortic regurgitation
- Rheumatic Heart Disease (mitral prolapse)
- patent ductus arteriosus
What is Cardiomyopathy and what are the three major types?
- structurally and functionally ABNORMAL heart with mechanical and/or electrical dysfunction in ABSENCE of coronary artery disease, HTN, valvular disease, and congenital heart disease
- Dilated (90% of cases), Hypertrophic, Restrictive
What are 5 common causes of Dilated Cardiomyopathy? (F/P/A/D/IO)
- familial (30-50%) due to TITIN AD mutation (TTN gene)
- peripartum (multifactorial) - late in pregnancy
- volume overload
- alcohol: wet beri-beri (thiamine deficiency)
- DOXORUBICIN (chemo drug)
- IRON OVERLOAD due to Hereditary Hemochromatosis (HFE gene) or multiple transfusions
What is morphology of Dilated Cardiomyopathy?
How does it present clinically?
M: dilation of ALL CHAMBERS and is often hypertrophic (inc. weight without thickened ventricle walls) and functional regurgitation
C: manifests between 20-50 yo with progressive CHF
- arrhythmias and thrombi formation
SYSTOLIC DYSFUNCTION
What is Takotsubo Cardiomyopathy?
Who does it commonly affect and what is it described as looking like?
- form of Dilated Cardiomyopathy associated with emotional distress (“broken heart syndrome”)
- sudden catecholamine surge causes apical ballooning of LV, as well as inc. contractility and Coronary A. constriction (acute MI)
- common in 60-75 yo FEMALES; looks like Japanese Octopus Pot
What is Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)?
- defective cell adhesion proteins in desmosomes linking myocytes cause RIGHT ventricular failure and arrhythmias (myocytes replaced by adipose and fibrosis w/dilation)
- classically familial and Auto Dominant
- causes ventricular tachycardia or fibrillation leading to sudden death
What is Naxos Syndrome?
- variant of ARVC with plantar and palmar hyperkeratosis and wooly hair
- caused by mutation in gene encoding PLAKOGLOBIN (desmosome-associated protein); adipose and fibrosis of right ventricular wall (SUDDEN DEATH)
- Auto RECESSIVE; presents as heart disease after 12 yo (need defib implant)
What is Hypertrophic Cardiomyopathy?
What is its histological appearance?
What mutation is most commonly implicated?
- relative common genetic disorder w/MALE prominence characterized by marked myocyte hypertrophy/disarray of SEPTAL PROMINENCE (no dilation)
- mutation is commonly Beta-Myosin heavy chain (B-MHC)
histo shows irregular and whorled myocytes
DIASTOLIC DYSFUNCTION
How does Hypertrophic Cardiomyopathy present clinically?
What is the classic presentation?
- usually asymptomatic
- ventricular arrhythmias = sudden death, mitral valve regurg. (systolic ejection murmur), exertional dyspnea and chest pain; palpitations
Classically: young teenage athlete dies while exercising
What is Restrictive Cardiomyopathy and what is it caused by? (A/F)
- dec. ventricular compliance leading to DIASTOLIC DYSFUNCTION (impaired filling)
- can be caused by amyloid deposition or increased fibrosis due to radiation
- ventricles are usually NORMAL size while both atria are ENLARGED –> congestive heart failure
What is Amyloid-associated Restrictive Cardiomyopathy?
What staining is done to test for it?
What are two common causes of this?
- extracellular deposition of proteins forming insoluble B-pleated sheets with APPLE GREEN birefringence on CONGO RED STAIN
- can be caused by mutated Transthyretin or Senile Amyloidosis (normal transthyretin)
Other Forms of Restrictive Cardiomyopathy
- Endomyocardial Fibrosis
- Loeffler Endocarditis (two cancer association)
- Endocardial Fibroelastosis
- children in tropical regions (Africa)
- fibrosis of endocardium and subendocardium
- seen in tropical regions
- EOSINOPHILIC infiltration
- associated with leukemia and lymphoma
- fibroelastic thickening of LV endocardium in 1st 2 YEARS of LIFE
- associated w/congenital heart defects
What is the most common infection associated with Myocarditis?
COXSACKIEVIRUS B
viral infection is the most common cause of myocarditis
What does infectious myocarditis due to Chagas Disease look like?
What is used to visualize it?
- caused by triatomine bug or “Kissing Bug”
- can see AMASTIGOTES on lower power imaging of myocytes
- use GIEMSA-stain to visualize Trypanosoma cruzi
How do Trichinosis and Lyme Syndrome cause infectious myocarditis?
T: helminthic infection due to eating undercooked pork
- larvae enter bloodstream and create cysts in muscle
LS: caused by spirochetes and is associated with Erythema Migrans (Bulls Eye rash) and polyarthritis/neurological issue
- carditis with TRANSIENT HEART BLOCK
What is is the difference between Lymphocystic and Eosinophilic Myocarditis?
L: most common form
- due to viral/post viral infection, autoimmune, idiopathic
E: marked inc. eosinophils
- due Hypersensitivity Myocarditis (allergy/hypersens)
- also idiopathic: methyl dopa and sulfonamides
- EXCLUDE PARASITIC INFECTION
Myocarditis with Giant Cells
What is the difference between Idiopathic Giant Cell Myocarditis and Myocardial Sarcoidosis?
IGC: aggressive with poor prognosis (< 3 months)
- admixed w/variable inflammation (eosinophils)
MS: immune-mediated granulomatous reaction
- giant cells w/non-necrotizing granulomas
What are two common cardiotoxic drugs (D/D) and what condition do they lead to?
What are 3 additional drugs that rarely cause serious injury? (L/P/C)
- Doxorubicin and Daunorubicin (chemo drugs)
- cause Dilated Cardiomyopathy and heart failure (dose-dependent lifetime toxicity)
also lithium (moods), phenothiazines (psychotics), and chloroquine (antimalarial) can occasionally cause reversible injury
What is the difference between Slow Accumulation and Acute Pericardial effusions?
SA: < 500 mL that’s asymptomatic and has “heart shadowing” on CXR
A: 200-300 mL rapid accumulation (< 1 wk) that can cause symptomatic (or fatal) cardiac tamponade
**normal: < 50 mL clear, straw colored fluid
What is the difference between Fibrinous/Serofibrinous, Serous, and Purulent pericarditis?
F/S: MOST COMMON; “bread and butter” apperance
- Acute MI, Dressler’s Syndrome
- see with uremia (chronic kidney disease, inc BUN)
S: viral or noninfectious inflammatory disease
P: ACTIVE infection via microbial invasion
What is Pericarditis and how does it present?
What does an ECG of a pt. with Pericarditis look like and what positions do they experience less pain?
- inflammation of pericardial sac
signs: chest pain (worse w/breathing), pericardial FRICTION RUB and effusion, fever
ECG: ST elevation (concave) and PR depression
- pt. has less pain sitting up, more pain lying down
What is the difference between Caseous, Hemorrhagic, and Constrictive pericarditis?
Ca: tuberculosis in origin, sometimes fungal
- looks “cheese-like” w/necrotizing granuloma
H: most commonly due to spread of malignant neoplasm; also TRAUMA
Co: dense, fibrous/fibrocalcific scar that limits diastolic expansion and cardiac output
- mimics restrictive cardiomyopathy
What is the most common cardiac tumor of adults and children?
Adults: myxoma
Children: rhabdomyoma
metastatic tumors are MORE COMMON than primary tumors
What is a Cardiac Myxoma and where does it typically occur?
What are common signs of Myxoma? (BV/F/P)
- stromal tumor of mesenchymal origin (gelatinous –> solid) located on LEFT ATRIUM in septal region of FOSSA OVALIS
signs: causes “Ball-Valve” obstruction that does mechanical valve damage (wrecking ball) –> embolization; fever (IL-6 inc. via tumor), and “plop” sound on ascultation
What are the differences between Cardiac Lipoma and Papillary Fibroelastoma?
L: localized mature lobulated fat mass
- can occur throughout the heart
PF: usually incidental; looks like “sea-anemone”; > 80% are located on the VALVES
- look like LAMBL EXCRESCENCES
- have avascular core
What are the differences between Cardiac Rhabdomyoma and Angiosarcoma?
What are the two genetic components of Rhabdomyoma?
R: most frequent benign tumor of pediatric heart
- hamartoma of developing cardiac myocytes
- 50% sporadic, 50% due tuberous sclerosis
- mutations in TSC1 (hamartin)/TSC2 (Tuberin)
see large, vacuolated cells; “spider cells”
A: malignant endothelial neoplasm that typically affects older adults
What is the difference between Cellular Mediated and Antibody Mediated Allograft Rejection after heart transplant?
CM: T cells; lymphocytic response
AM: antibodies; vascular neutrophilic inflammation
- reactive endothelium and macrophages
What is Allograft Vasculopathy?
What is a major clinical problem it leads to and why?
- late, progressive, diffusely stenosing intimal proliferation (50% in 5 yrs, all pts. within 10 yrs)
- causes concentric intimal thickening of BVs
- leads to SILENT MI; due to denervated transplanted heart (NO ANGINA)
