Arrhythmias, SCD, HTN, Cardiac Valve Dz, Cardiomyopathy, Pericardial Dz, Cardiac Tumors, Transplantation

Question 1

Ischemic injury is the most common cause of rhythm disorders including sick sinus syndrome, afib, and heart block. What is sick sinus syndrome?

Answer 1

Bradycardia d/t SA node damage

Question 2

Condition in which myocytes depolarize independently and sporadically (atrial dilation) with variable transmission through AV node; auscultated as irregularly irregular rhythm

Answer 2

Atrial fibrillation

Question 3

Heart block occurs as a result of dysfunctional ___ node

What are the 3 degrees of heart block?

Answer 3

AV

3 degrees of heart block:

First degree = prolonged PR interval

Second degree = intermittent transmission

Third degree = complete failure

Question 4

Arrhythmias may result from abnormalities in ____ junction structure or spatial relationship, such as those that occur in IHD, dilated cardiomyopathies, myocyte hypertrophy, inflammation (myocarditis or sarcoid), amyloid, etc

Answer 4

Gap

Question 5

Most hereditary conditions resulting in arrhythmia are _____ inheritance. Primary electrical disorders are dx through genetic testing. ______ are diseases associated with mutations in genes that are required for normal ion channel function, often associated with skeletal m. disorders and diabetes

Answer 5

Autosomal dominant; channelopathies

Question 6

Most common inherited arrhythmogenic disease

Answer 6

Long QT syndrome

[associated with gene defects in KCNQ1, KCNH2, SCN5A, CAV3; results in LOF of K+ channel or GOF of Na channel or caveolin]

Question 7

4 inherited arrhythmogenic diseases

Answer 7

Long QT syndrome (most common)

Short QT syndrome (GOF in K+ channel)

Brugada syndrome (LOF in Na or Ca channel)

CPVT syndrome (GOF or LOF in diastolic Ca release)

Question 8

Sudden cardiac death is due to a fatal _____ most often arising from ischemia-induced myocardial irritability; it may occur without symptoms or within 1-24 hours of symptom onset. 80-90% of successively resuscitated pts show ____ on ECG

Answer 8

arrhythmia; Nothing!

80-90% show no lab or ECG changes

Question 9

_______ precipitates sudden cardiac death in 80-90% of cases

Answer 9

CAD — usually with >75% stenosis of one or more of the 3 main coronary arteries

Unfortunately, SCD may be the first manifestation of IHD; healed remote MIs are seen in about 40%

Question 10

CAD is the most common cause of sudden cardiac death. What are some other possible causes?

Answer 10

Cardiomyopathy, myocarditis, congenital abnormalities of conduction system, myocardial hypertrophy

Question 11

Describe changes in the heart with left-sided hypertensive disease

Answer 11

Pressure overload —> left ventricular hypertrophy (concentric thickening)

Diastolic dysfunction can result in left atrial enlargement, which may lead to afib

May lead to CHF

Risk factor for SCD!

Question 12

Describe right-sided hypertensive disease

Answer 12

Isolated right-sided hypertensive heart disease arises in the setting of pulmonary hypertension

Acute cor pulmonale may arise from a large pulmonary embolus —> marked dilation of RV without hypertrophy

[remember most common cause of pulmonary HTN is LEFT-sided heart dz]

Question 13

Diseases predisposing to cor pulmonale include diseases of pulmonary parenchyma, diseases of pulmonary vessels, disorders affecting chest movement, and disorders inducing pulmonary arterial constriction. What are some associated diseases of the pulmonary parenchyma?

Answer 13

COPD
Diffuse pulmonary interstitial fibrosis
Pneumoconiosis
Cystic fibrosis
Bronchiectasis

Question 14

Diseases predisposing to cor pulmonale include diseases of pulmonary parenchyma, diseases of pulmonary vessels, disorders affecting chest movement, and disorders inducing pulmonary arterial constriction. What are some associated diseases of the pulmonary vessels?

Answer 14

Recurrent PE
Primary pulm HTN
Extensive pulmonary arteritis
Drug, toxin, radiation-induced obstruction
Extensive pulmonary tumor microembolism

Question 15

Diseases predisposing to cor pulmonale include diseases of pulmonary parenchyma, diseases of pulmonary vessels, disorders affecting chest movement, and disorders inducing pulmonary arterial constriction. What are some associated disorders affecting chest movement?

Answer 15

Kyphoscoliosis
Marked obesity (OSA, pickwickian syndrome)
Neuromuscular dz

Question 16

Diseases predisposing to cor pulmonale include diseases of pulmonary parenchyma, diseases of pulmonary vessels, disorders affecting chest movement, and disorders inducing pulmonary arterial constriction. What are some associated diseases inducing pulmonary arterial constriction?

Answer 16

Metabolic acidosis
Hypoxemia
Chronic altitude sickness
Obstruction of major airways

Question 17

What is the difference between valvular stenosis and valvular insufficiency?

Answer 17

Stenosis = valve doesn’t OPEN completely; occurs chronically, impeding FORWARD flow

Insufficiency = valve doesn’t CLOSE completely; may occur acutely or chronically, allowing REVERSED flow

Question 18

Chronic stenosis may cause _____ overload hypertrophy —> CHF

Chronic insufficiency may cause ____ overload hypertrophy —> CHF

Answer 18

Pressure

Volume

Question 19

Virtually the ONLY cause of mitral stenosis

Answer 19

Postinflammatory scarring d/t rheumatic heart disease

Question 20

Causes of mitral regurgitation

Answer 20

Abnormalities of leaflets and commissures: postinflammatory scarring, infective endocarditis, mitral valve prolapse, drugs (fen-phen)

Abnormalities of tensor apparatus: rupture of papillary muscle, papillary muscle dysfunction/fibrosis, rupture of chordae tendinae

Abnormalities of LV and/or annulus: LV enlargement (myocarditis, dilated cardiomyopathy), calcification of mitral ring

Question 21

Causes of aortic stenosis

Answer 21

Postinflammatory scarring (rheumatic heart disease)

Senile calcific aortic stenosis

Calcification of congenitally deformed valve

Question 22

Causes of aortic regurgitation

Answer 22

Abnormalities of leaflets and commissures: postinflammatory scarring (RHD)

Abnormalities of tensor apparatus: degenerative aortic dilatation, SYPHILITIC AORTITIS, ankylosing spondylitis, rheumatoid arthritis, MARFAN

Question 23

Most common valve abnormality and commonly associated comorbidities

Answer 23

Calcific aortic stenosis — “wear and tear” phenomenon associated with chronic HTN, hyperlipidemia, and inflammation

Question 24

With calcific aortic stenosis, ____ valves will show an accelerated course. Affected valves contain ____-like cells which deposit substance that creates mounded calcifications in cusps which prevent complete opening of the valve

Answer 24

Bicuspid; osteoblast (deposit osteoid like substance that ossifies)

Question 25

Symptoms and clinical features of calcific aortic stenosis

Answer 25

Angina, CHF, or syncope Increased pressure causes LVH Most pts with aortic stenosis will die within 5 years of developing angina, within 3 years of developing syncope, and within 2 years of CHF onset

Question 26

Mitral annular calcification involves calcific deposits in the fibrous annulus. It normally does NOT affect valve function. However, nodules may becomes sites for ______ formation or _____ _____. It is most common in females > males, > 60 yrs, and with pts who have ________

Answer 26

Thrombus; infective endocarditis; mitral valve prolapse

Question 27

Most bicuspid aortic valves are prone to calcification. Patients can remain relatively asymptomatic until stenosis reaches a critical point when _____ rapidly ensues. The dense white nodules of calcification are present on both valve surfaces

Answer 27

CHF [while bicuspid aortic valves are especially susceptible, an aortic valve does not need to be bicuspid to calcify. Sometimes in older adults, a normal aortic valve will undergo calcification = “senile calcific aortic stenosis”]

Question 28

Mitral valve prolapse often occurs in those with ____ syndrome or as a complication of other cuases of regurgitation like dilated hypertrophy. On auscultation, a _____ may be noted

Answer 28

Marfan; mid-systolic click

Question 29

Mitral valve prolapse occurs when valve leaflets prolapse into the ____ during systole. It affects 2-3% of adults in the US with a female predominance. Leaflets become thickened and rubbery due to disorganized ______ deposits, aka ______ degeneration, and elastic fiber disruption

Answer 29

LA; proteoglycan; myxomatous

Question 30

Symptoms and complications associated with mitral valve prolapse

Answer 30

Most are asymptomatic but a minority may experience pain mimicking angina and/or dyspnea ``` Serious (but rare) complications may include: Infective endocarditis Mitral insufficiency Thromboembolism Arrhythmias ```

Question 31

Rheumatic fever is a multisystem inflammatory disorder occurring 10 days to 6 weeks following pharyngeal infection with _________; acute rheumatic fever may include a carditis component, and over time may evolve into ____________

Answer 31

Group A streptococcus Chronic rheumatic heart disease

Question 32

Pathogenesis of rheumatic fever

Answer 32

Immune response to streptococcal M proteins, which cross react with cardiac (among other) self-Ags

Question 33

Lab tests used to dx acute rheumatic fever

Answer 33

ASO and anti-DNase B

Question 34

General clinical features of rheumatic fever

Answer 34

``` Pancarditis Migratory polyarthritis Subcutaneous nodules Rash (erythema marginatum) Syndenham chorea ```

Question 35

Specific cardiac features of acute rheumatic fever

Answer 35

Pancarditis featuring Aschoff bodies Inflammation and fibrinoid necrosis of endocardium and left-sided valves, with verrucae (vegetations) [Repeated strep infections will cause these features to recur!]

Question 36

Cardiac findings with chronic rheumatic heart disease

Answer 36

Mitral leaflet thickening, fusion and shortening of commissures, fusion and thickening of tendinous cords, resulting in mitral stenosis, neovascularization LA enlargement may lead to afib or thromboembolic events Pulmonary congestion/RHF Infective endocarditis Surgical repair/prosthetic valve replacement

Question 37

Where do the verrucae tend to line up in rheumatic fever?

Answer 37

Along lines of valve closure

Question 38

Central wavy ribbon of chromatin in macrophages is characteristic of ____ cells in acute RHD

Answer 38

Anitschkow

Question 39

Infective endocarditis is an infection of valves and endocardium, characterized by ____ consisting of microbes and debris, associated with underlying tissue destruction. What is the difference between acute and subacute IE?

Answer 39

Vegetations Acute: rapidly progressing, destructive infection of previously normal valve; requires surgery in addition to abx. Necrotizing, ulcerative destructive lesions, ring abscesses, emboli —> septic infarcts or mycotic aneurysm Subacute: slower-progressing infection of previously deformed valve (such as chronic RHD); can often be cured with abx alone. Granulation tissue, fibrosis, calcification, chronic inflammatory cells, vague flu-like sxs

Question 40

Predisposing conditions to infective endocarditis

Answer 40

Valvular abnormalities — RHD, prosthetic valves, MV prolapse, calcific stenosis, bicuspid AV Bacteremia — another site of infection, dental work, surgery, contaminated needle, compromised epithelium

Question 41

Classic features of infective endocarditis

Answer 41

Friable, bulky destructive valvular vegetations; pts present with fever, weight loss, fatigue Left-sided vavles more commonly affected - usually hear murmur (right-sided valves — think IV drug users) Friability leads to septic emboli (PE if right sided valve) Vegetations are mixtures of fibrin, inflammatory cells, and organisms; subacute vegetations may have granulation tissue component

Question 42

Organisms typically involved in infective endocarditis

Answer 42

S.viridans —> valve abnormalities S.aureus —> normal valves, abnormal valves, IV drug abusers S.epidermidis —> prosthetic valves HACEK: Hemophilus, Actinobacillus, Cardiobacterium, Eikenella, Kingella

Question 43

In summary: vegetative endocarditis manifesting as — Warty, line of closure = _____ Large, irregular = _______ Small, line of closure = ______ Both sides of valve affected = ____

Answer 43

RHD IE NBTE LSE (libman sacks endocarditis — think lupus)

Question 44

Name some of the vascular lesions and immunologic phenomena that constitute minor diagnostic criteria for infective endocarditis

Answer 44

Vascular lesons: arterial petechiae, subungual/splinter hemorrhages, Janeway lesions Immunologic phenomena: osler nodes, roth spots

Question 45

Disease characterized by small, sterile thrombi on cardiac valve leaflets along the line of closure that are loosely attached, non-invasive, and do not elicit an inflammatory reaction but may be a source of emboli; associated with malignancy (especially mucinous adenocarcinomas), sepsis, or catheter-induced endocardial trauma

Answer 45

Nonbacterial thrombotic endocarditis (NBTE)

Question 46

Systemic disorder marked by flushing, diarrhea, dermatitis, and bronchoconstriction d/t release of bioactive compounds such as serotonin

Answer 46

Carcinoid syndrome [5-hydroxyindoleacetic acid levels correlate with severity of cardiac lesions]

Question 47

50% of pts with systemic carcinoid syndrome develop cardiac manifestations. Describe carcinoid heart disease

Answer 47

Affects right endocardium and valves; the left side is protectd d/t pulmonary vascular bed degradation of mediators [lesions appear similar to pts taking fen-phen or ergot alkaloids for migraine as they affect systemic serotonin metab]

Question 48

Gross and histologic findings associated with carcinoid heart dz

Answer 48

Grossly: glistening white intimal plaque-like thickenings of the endocardial surfaces of the cardiac chambers and valve leaflets Histo: intimal thickening (acid mucopolysaccharide-rich)

Question 49

Complications of cardiac valve prostheses

Answer 49

Thrombosis/thromboembolism Anticoagulant-related hemorrhage Prosthetic valve endocarditis Structural deterioration — wear, fracture, poppet failure in ball valves, cuspal tear, calcification Inadequate healing (paravalvular leak), exuberant healing (obstruction), hemolysis

Question 50

Most common cardiomyopathy and its associated mechanism of heart failure

Answer 50

Dilated cardiomyopathy — causes impairment of contractility (systolic dysfunction) — also has most significant change in EF —> <40% [indirect myocardial dysfunction includes IHD, valvular heart disease, hypertensive heart disease; congenital heart disease]

Question 51

Causes of dilated cardiomyopathy

Answer 51

``` Genetic Alcohol Peripartum Myocarditis Hemochromatosis Chronic anemia Doxorubicin toxicity Sarcoidosis Idiopathic ```

Question 52

What 2 types of cardiomyopathy result from impairment of compliance (diastolic dysfunction)?

Answer 52

Hypertrophic cardiomyopathy — presents like hypertensive heart disease or aortic stenosis Restrictive cardiomyopathy — presents like pericardial constriction

Question 53

LV EF and causes of hypertrophic cardiomyopathy

Answer 53

LV EF = 50-80% Causes: genetic, friedrich ataxia, storage diseases, infants of diabetic mothers

Question 54

LV EF and causes associated with restrictive cardiomyopathy

Answer 54

LV EF = 45-90% Causes: amyloidosis; radiation-induced fibrosis; idiopathic

Question 55

Dilated cardiomyopathy = progressive cardiac dilation and systolic dysfunction, usually with dilated hypertrophy What are the genetic components of dilated cardiomyopathy?

Answer 55

Thought to be familial in 30-50% of cases TTN (titin) mutations may account for 20% of all cases Usually autosomal dominant

Question 56

Risk factors and associations in the pathogenesis of dilated cardiomyopathy

Answer 56

Alcohol is strongly linked to DCM Myocarditis Cardiotoxic drugs/substances like doxorubicin and iron overload (may occur with hereditary hemochromatosis (HFE mutation))

Question 57

Morphology of dilated cardiomyopathy

Answer 57

Dilation of all chambers Mural thrombi are common Functional regurgitation of valves

Question 58

Clinical Presentation of dilated cardiomyopathy

Answer 58

Usually manifests between ages 20-50 Progressive CHF —> dyspnea, exertional fatigue, decreased EF (<25% end stage) Arrhythmias Embolism

Question 59

Cardiomyopathy associated with excess catecholamines following extreme emotional or psychological stress; occuring in women 90% of the time, typically ages 58-75

Answer 59

Takotsubo cardiomyopathy

Question 60

What cardiomyopathy is associated with apical ballooning of the left ventricle with abnormal wall motion and contractile dysfunction?

Answer 60

Takotsubo cardiomyopathy

Question 61

Hypertrophic cardiomyopathy is considered 100% genetic. What is the associated phenotype?

Answer 61

Marked hypertrophy as well as asymmetrical septal hypertrophy MYOFIBER DISARRAY Fibrosis LV outflow tract plaques Thickened septal vessels

Question 62

Describe myocardial findings and inheritance pattern associated with arrhythmogenic right ventricular cardiomyopathy (ARVC)

Answer 62

Right ventricular failure and arrhythmias — myocardium of the right ventricular wall is replaced by ADIPOSE and FIBROSIS —> ventricular tachycardia or fibrillation —> sudden death Familial, autosomal dominant (defective cell adhesion proteins in desmosomes that link adjacent cardiac myocytes)

Question 63

Arrhythmogenic right ventricular cardiomyopathy with hyperkeratosis of plantar palmar skin surfaces

Answer 63

Naxos syndrome

Question 64

Naxos syndrome = Arrhythmogenic right ventricular cardiomyopathy with hyperkeratosis of plantar palmar skin surfaces. This is caused by mutations in the gene encoding the desmosome-associated protein ______

Answer 64

Plakoglobin

Question 65

Hypertrophic cardiomyopathy is a genetic disorder leading to myocardial hypertrophy and diastolic dysfunction —> reduced stroke volume and often ventricular outflow obstruction. It is due to numerous mutations involving _____ proteins, most commonly ______

Answer 65

Sarcomeric; beta-myosin heavy chain

Question 66

Consequences of hypertrophic cardiomyopathy

Answer 66

Foci of myocardial ischemia may occur Left atrial dilation and mural thrombus Diminished CO and increased pulmonary congestion —> exertional dyspnea (may be seen in athletes!) Arrhythmias Sudden death!

Question 67

In what type of cardiomyopathy are the ventricles usually normal sized but BOTH atria can be enlarged?

Answer 67

Restrictive cardiomyopathy

Question 68

Describe restrictive cardiomyopathy

Answer 68

Decreased ventricular compliance (increased stiffness) —> diastolic dysfunction (impaired filling), while systolic function of LV remains normal May be secondary to deposition of material within the wall (amyloid) or increased fibrosis (radiation) Ventricles are usually of normal size but both atria can be enlarged

Question 69

Describe restricive cardiomyopathy associated with amyloid deposition

Answer 69

Extracellular deposition of proteins which form an insoluble beta pleated sheet — stains with congo red stain —> apple green birefringence May be systemic (myeloma) or restricted to the heart (usually transthyretin) Note: certain mutated version fo transthyretin are more amyloidogenic; amyloid can involve different parts of the heart, but when deposits are in the interstitium of the myocardium, a restrictive cardiomyopathy results

Question 70

In the US, myocarditis is most commonly due to a virus. What are the most common viruses implicated? What are some other infectious causes?

Answer 70

Most common = Coxsackie A and B Other infectious causes = Trypanosoma cruzi (Chagas disease), various bacteria and fungi

Question 71

Describe myocarditis caused by trypanosoma cruzi

Answer 71

10% die during acute attack May progress to cardiac insufficiency in 10-20 years Parasitization of scattered myofibers; mixed inflammatory cell infiltrate (PMN, lymphocytes, macrophages, and occasional eosinophils)

Question 72

Noninfectious causes of myocarditis

Answer 72

Immune mediated reactions including RF, SLE, drug hypersensitivity (see eosinophils on histology!! Vs. parasites if caused by chagas)

Question 73

Pericardial disease is characterized by > 50 mL of fluid surrounding the heart. What is the difference between slow vs. fast accumulation?

Answer 73

Slow accumulation of <500 mL may remain symptomatic as long as it is slow enough — may see globular enlargement of the heart shadow on CXR An acute, rapid gain of 200-300 mL —> cardiac tamponade

Question 74

Most common types of pericardial disease

Answer 74

Fibrinous and serofibrinous — associated with AMI, postinfarction (Dressler’s), uremia, chest irradiation, RF, SLE, trauma, etc. Fibrinous = dry, finely granular Serofibrinous = yellow-brown, turbid fluid w/ WBCs, RBCs, and fibrin

Question 75

Symptoms of fibrinous or serofibrinous pericarditis

Answer 75

Pain (sharp, pleuritic, and positional) Fever +/- CHF Most striking feature = loud pericardial friction rub!

Question 76

Primary cardiac tumors are rare, what are some examples?

Answer 76

``` Myxoma Fibromas Lipomas Papillary fibroelastomas Rhabdomyomas Angiosarcomas ```

Question 77

Most common primary, pedunculated or sessile, cardiac tumor; usually located in region of fossa ovalis

Answer 77

Myxoma

Question 78

Familial syndromes associated with myxomas have activating mutations in the ____ gene, in association with ______ syndrome; OR null mutations in ______ as part of the _____ complex

Answer 78

GNAS1; McCune-Albright PRKAR1A; Carney

Question 79

Describe appearance of myxoma

Answer 79

Globular hard mass, mottled with hemorrhage; may also be soft, translucent, papillary, or villous with a gelatinous appearance

Question 80

Symptoms associated with myxoma

Answer 80

“Ball-valve” obstruction — meaning sxs may be positional The pedunculated form causes intermittent obstruction during systole of AV valve; or “wrecking ball” causing damage to the valve leaflets Constitutional sx: elaboration of IL-6 by some myxomas Auscultation may reveal positional “tumor plop”

Question 81

Describe major complications associated with heart transplants

Answer 81

Allograft rejection (requires routine endomyocardial bx to monitor) Allograft arteriopathy = most important long-term compl. —late, progressive, diffusely stenosing intimal proliferation, silent MI (denervated transplanted heart = no angina) EBV associated B-cell lymphoma — d/t chronic T-cell immunosuppression