L23- CVS Pathology IV

Question 1

define systemic hypertensive heart disease and briefly explain pathogenesis

Answer 1

-LV hypertrophy, no evidence of other causes besides HTN

Sustained pressure overload –> GFs + local mechanical effects –> upregulate actin / myosin expression => hypertrophy

Question 2

HTN LV hypertrophy is considered (concentric/eccentric) and the heart will weigh (2). In long-standing cases (3) is often observed. On histology, myocytes will appear (4).

Answer 2

1- concentric
2- 400-600g
3- RV hypertrophy and dilatation
4- enlarged with large hyperchromatic, rectangular, ‘box-car’ shaped nuclei

Question 3

describe the clinical features (and progression) of systemic hypertensive heart disease

Answer 3

Early- asymptomatic

• ->
• angina
• signs/sxs of LHF
• ->
• CVA, renal failure (via HTN)
• SCD (sudden cardiac death)

Question 4

Pulmonary hypertensive heart disease, aka (1), is defined as (2). Note- (3), (4) are excluded from (2).

Answer 4

1- cor pulmonale
2- R sided cardiac chamber disease secondary to pulmonary parenchymal or vascular disease
3- pulmonary HTN due to LHF
4- pulmonary HTN due to congenital heart disease

Question 5

describe the appearance of acute cor pulmonale

Answer 5

(pulmonary hypertensive heart disease)
-Pulmonary Embolism => sudden inc of burden on RV / R heart
=> RV dilatation (no hypertrophy)

Question 6

The most common cause of chronic cor pulmonale is (1), but other causes include (2). The R heart will have the following changes: (3).

Answer 6

(pulmonary hypertensive heart disease)
1- COPD
2- idiopathic, pulmonary fibrosis, cystic fibrosis, marked obesity
3- RV hypertrophy, RA hypertrophy and dilatation

Question 7

(1) is the generalized inflammation of myocardium where (2) is the primary cause to its development and myocardial (3). It is associated with (4) of the myocardium.

Answer 7

1- myocarditis
2- inflammatory process
3- myocardial injury
4- necrosis / degeneration of myocytes

Question 8

The most common cause of myocarditis is (1), specifically (2) in most cases. Pathogenesis involves the following three steps, (3).

Answer 8

1- viral
2- coxsackie A/B, enteroviruses
3- direct viral cytotoxicity –> cell-mediated immune rxns against infected myocytes –> CKs released aggrevate myocardial dysfunction

Question 9

describe the gross and histological appearance of viral myocarditis

Answer 9

Gross:

• dilated, flabby heart (or normal)
• cut surface that has patchy pallor and mottling
• possible mural thrombi

Histo:

• interstitial inflammation, mainly lymphocytes, few plasma cells
• focal necrosis of myocytes – adjacent to inflammatory cells

Question 10

describe clinical presentation of myocarditis and the investigation used in diagnosis

Answer 10

• Varies: asymptomatic – sudden acute HF / arrhythmias
• Nonspecific (mostly): flu-like sxs, fatigue, dyspnea, palpitations, chest pain, fever (may mimic acute MI sxs)

Investigations: PCR for viral nucleic acids, serological studies

Question 11

list the complications of myocarditis

Answer 11

• acute HF
• dilated cardiopathy –> chronic HF (viral type)
• arrhythmias: ventricular is most dangerous, leading to possible SCD

Question 12

describe the outcomes of myocarditis

Answer 12

• mostly a self limiting disease (spontaneous resolution)
• if Pt survives acute phase –> inflammation resolves –> healing with total resolution or progressive fibrosis

(majority recover completely)

Question 13

list the 3 parasites (and theie associated disease) that cause myocarditis

Answer 13

• trichinella spiralis; trichinosis: infects muscle
• trypanosoma cruzi; Chaga’s disease
• toxoplasmosis, toxoplasma gondii

Question 14

Parasitic Myocarditis, indicate the microorganism:

(1) is most common cause
(2) common in immunocompromised
(3) related to cats
(4) endemic in South America

(5) parasitization of scattered myofibers by it with accompanied mixed inflammatory infiltrate
(6) shows eosinophilic predominance on histology

Answer 14

Trichella Spiralis (trichinosis): 1, 6

Trypanosoma Cruzi (Chaga’s disease): 4, 5

Toxoplasmosis (toxoplasma gondii): 2, 3

Question 15

(bacterial/fungal/parasitic/fungal) myocarditis is occurs in immuno-compromised individuals, where it is characterized by the presence of (2) in the myocardium

Answer 15

1- fungal (Candida spp.)

2- mixed inflammatory infiltrate: neutrophils, lymphocytes, plasma cells

Question 16

list the 2 types on noninfectious myocarditis

Answer 16

• immunologically medicated

- giant cell myocarditis

Question 17

Immunological medicated (noninfectious) is related to (1) diseases and (2) drugs. It is described as (3) in nature and severity and the inflammatory response is composed of (4).

Answer 17

1- SLE, polymyositis
2- (drug hypersensitivies) methyldopa, sulfonamides
3- mild, self-limiting (resolves spontaneously)
4- lymphocytes, macrophages, high in eosinophils

Question 18

Giant cell myocarditis has a (1) cause and can be associated with (2) diseases. It is dangerous in (3) people as (4) can cause death. Its histological appearance is described as (5).

Answer 18

1- idiopathic (maybe immune origin)
2- SLE, thyrotoxicosis
3- 20-40s people
4- CHF, arrhythmias
5- granulomatous inflammation: giant cells, lymphocytes, eosinophils plasma cells + focal extensive necrosis

Question 19

define Cardiomyopathy and list the three main categories

Answer 19

-primary myocardial disease excluding ischemia, HTN, valvular lesions, congenital anomalies, inflammatory disorders as causes

1) dilated CM (includes arrhythmogenic RV CM)
2) hypertrophic CM
3) restrictive CM

Question 20

The most common type of CM is (1), aka (2). It is characterized by progressive cardiac (dilatation/hypertrophy), (concentric/eccentric) hypertrophy, and (diastolic/systolic) dysfunction. It will eventually lead to (6).

Answer 20

1- DCM (dilated)
2- congestive CM
3- dilatation
4- eccentric hypertrophy
5- systolic, contractile dysfunction
6- progressive HF

Question 21

list the common caused of DCM (hint- 8)

Answer 21

1) idiopathic (most cases)
2) genetic mutations
3) EtOH: direct cytotoxicity
4) Viral Myocarditis (coxackie B virus)
5) Nutritional disturbances: thiamine/vitB1 deficiency, chronic anemia
6) chemotherapy: doxorubicin
7) pregnancy associated / peripartum DCM
8) stress provoked

Question 22

describe the genetic causes of DCM

Answer 22

(25-35% of cases)
Most common: AD mutations affecting cytoskeleton

Less common: X-linked mutations to dystrophin

Uncommon: mutations of mitochondrial proteins in oxidative phosphorylation

Question 23

Peripartum CM (DCM) occurs during (1) and is associated with (2). (3)% of cases will recover spontaneously.

Answer 23

1- late gestation to few weeks after delivery
2- volume overload, HTN, nutritional disturbances
3- 50%

Question 24

DCM will be exhibited in (1) heart chambers. In total the heart will appear (2) with (3) sized walls. There will (4) dysfunction, which can lead to (5), which can lead to (6).

Answer 24

1- all four chambers
2- enlarged, flabby, heavy (2-3x)
3- normal, thin, or thick walls
4- contractile dysfunction
5- mural thrombosis
6- embolization

Question 25

DCM Histology: (1) myocyte appearance (2) interstitial appearance (3) is also possibly seen due to (4) dysfunction leading to (5)

Answer 25

1- hypertrophied, enlarged nuclei // some thin and stretched out and irregular 2- fibrosis, mainly in endocardium 3- necrosis (myocytes) 4- contractile dysfunction 5- poor perfusion / ischemia

Question 26

DCM: - mostly affects (1) individuals - fundamental defect is (2) - EF of (3) - progresses to (4) - Tx: (5)

Answer 26

``` 1- 20-50 age group 2- contractile dysfunction 3- <25% (50-65% is normal) 4- CHF 5- cardiac transplantation ```

Question 27

ARVC, aka (1), is a (2) type disorder in nature / cause. It is characterized by (3) due to (4). (3) can lead to the following progression: (5). It is associated with a (6) defect and (7) disease.

Answer 27

1- arrhythmogenic right ventricular cardiomyopathy 2- AD inherited 3- thin RV 4- myocyte replacement by fatty infiltration 5- RHF, arrhythmia --> SCD 6- desmosomal adhesion protein 7- Naxos Syndrome

Question 28

HCM is characterized by (1- describe effect) and (2), and in 30% of cases (3). HCM will present with (4).

Answer 28

1- myocardial hypertrophy --> small LV chamber 2- abnormal diastolic filling 3- intermittent LV outflow obstruction (ant. leaflet of MV) 4- exertional dyspnea or SCD in young adults

Question 29

HCM is inherited in a (1) fashion and is the result of a (2) mutation in one of the following protein: (3). (2) will result in a (gain/loss) of function leading to (5) progression.

Answer 29

1- AD 2- point mutation 3- [sarcomeric protein] β-myosin heavy chain (most common), myosin binding protein C, cardiac troponin T 4- gain of function 5- myocyte hypercontractility --> inc energy use --> intense compensatory hypertrophy (myofiber disarray) + fibroblast proliferation

Question 30

HCM will have a (1) appearance on the walls and a (2) appearance of the cavity. (3) is the hallmark feature and (4) is another possible critical feature.

Answer 30

1- thick, massive hypertrophy w/o dilatation 2- banana-like configuration (longitudinal section) 3- Asymmetric Septal hypertrophy (most prominent in subaortic region) 4- endocardial plaque/sclerosis in L outflow tract

Question 31

HCM histology: (1) myocyte appearance (2) myocyte organization (3) interstitial appearance

Answer 31

1- hypertrophy, diameter >40µm (15µm is normal) 2- myofiber disarray: haphazard arrangement of hypertrophied, abnormally branching myocytes 3- fibrosis

Question 32

list the clinical features and symptoms of HCM and include its treatment

Answer 32

- exertional dypnea - angina / MI - harsh ejection systolic murmur - SCD via arrhythmia - CHF Tx: i) therapy to relax ventricles ii) partial septal muscle excision (reduce outflow obstruction)

Question 33

(1) is the least common type of CM. It is characterized by (2) leading to (3) progression and (diastolic/systolic) dysfunction.

Answer 33

1- Restrictive CM (RCM) 2- stiff walls 3- loss of ventricular compliance --> impaired ventricular filling during diastole 4- diastolic dysfunction OR systolic if systole is not forceful

Question 34

list the common causes of RCM

Answer 34

- endomyocardial fibrosis (most common) - Loffler's syndrome - radiation fibrosis - amyloidosis - hemochromatosis - metastatic tumors

Question 35

list the clinical features and complications due to RCM **indicate Dx requirement

Answer 35

Sxs: exertional dyspnea, fatigue, chest pain Complications: arrhythmias, CHF Dx: endomyocardial biopsy

Question 36

RCM Morphology: (1) ventricle appearance (2) cavity appearance (3) myocardium appearance (4) atrium appearance (5) interstitial appearance

Answer 36

``` 1- normal or slightly enlarged 2- not dilated 3- firm 4- both atria dilated 5- patchy variable fibrosis ```

Question 37

EMF is a (1) type of CM commonly found in (2) age group and (3) regions. It is characterized by (4) leading to (5) in the affected chambers.

Answer 37

``` (endomyocardial fibrosis) 1- restrictive CM 2- children, young adults 3- Africa, tropics 4- dense fibrosis of endocardium and subendocardium (from apex to AV valves) 5- reduced volume and compliance ```

Question 38

Loefflers Endomyocarditis is a (1) type of CM characterized by (2). It is caused by abundance of (3) in the periphery releasing (4) to damage (5).

Answer 38

``` 1- restrictive CM 2- endocardial fibrosis, with large mural thrombi 3- eosinophils + abnormal degranulation 4- MBP (major basic protein) 5- endocardium --> necrosis, fibrosis ```