3.3.2. Cardiac Pathology Part 3: Missing Information

Question 1

What in general causes cardiac hypertophy?

Answer 1

Sustained increased in mechanical work due to pressure or volume overload (e.g. those mediated through the activation of B-adrenergic receptors) causes myocytes to increase in size; cumulatively, this increases the size and weight of the heart

Question 2

What occurs with pressure-overload hypertrophy?

Answer 2

1. Due to hypertension or aortic stenosis
2. New sarcomeres are predominantly assembled in parallel
3. Causes concentric increase in wall thickness

Question 3

What occurs with volume overload hypertrophy?

Answer 3

1. Characterized by new sarcomeres being assembled in series within existing sarcomeres, leading primarily to ventricular dilation
2. Wall thickness may increase, stay the same, or decrease
3. Heart weight is a better measure of hypertrophy in dilated hearts

Question 4

Describe how nutrient and blood supply changes to a heart that has undergone hypertrophy

Answer 4

Myocyte hypertrophy is not accompanied by a proportional increase in capillary numbers; supply of oxygen and nutrients to hypertrophied hearts is more tenuous than the normal heart, but the oxygen consumption of the heart is elevated due to the increased workload

Therefore, the hypertrophied heart is vulnerable to ischemia-related decompensation

Question 5

Hypertrophy is often accompanied by deposition of ____ ____.

Answer 5

Hypertrophy is often accompanied by deposition of fibrous tissue

Question 6

The molecular and cellular changes in hypertrophied hearts that initially mediate enhanced function may themselves contribute to the development of heart failure in four ways:

Answer 6

Abnormal myocardial metabolism

Alterations of intracellular handling of calcium ions

Myocyte apoptosis

Reprogramming of gene expression

Question 7

Distinguish between forward and backward pump failure seen in CHF

Answer 7

CHF is characterized by variable degrees of cardiac output and tissue perfusion (sometimes called pump forward failure), as well as pooling of blood in the venous capacitance system (backward failure); the latter may cause pulmonary edema, peripheral edema, or both

Question 8

When we see splinter hemorrhages, what should we think of?

Answer 8

Endocarditis

Question 9

Mildest chest x ray finding suggesting pulmonary congestion

Answer 9

Perivascular and interstitial edema, particularly in the interlobular septa, responsible for the characteristic Kerly B and C lines noted on chest X-ray study in CHF

Question 10

Discuss how heart failure cells come around

Answer 10

Accumulation of edema fluid in the alveolar spaces. Some red cells and plasma proteins extravasate into the edema fluid within the alveolar spaces, where they are phagocytosed and digested by macrophages, which store the iron recovered from hemoglobin in the form of hemosiderin. These hemosiderin-laden macrophages (aka heart failure cells) are telltale signs of previous episodes of pulmonary edema. Pleural effusions arise from elevated pleural capillary pressure

Question 11

In right sided heart failure, we have huge effects in the liver and portal system. One symptom is the “nutmeg” liver. What causes this?

Answer 11

The liver is usually increased in size and weight (congestive hepatomegaly) due to prominent passive congestion, greatest around the central veins. Grossly, this is reflected as congested red-brown pericentral zones, with relatively normal-colored tan periportal regions, producing the characteristic nutmeg liver appearance

Question 12

____ ____ ____ are the major known causes of Congenital Heart Disease.

Answer 12

Sporadic genetic abnormalities are the major known causes of CHD.

Question 13

The most common genetic cause of CHD is trisomy 21

most often associated with structures derived from the ___ ___ ___.

Answer 13

The most common genetic cause of CHD is trisomy 21

most often associated with structures derived from the second heart field

Question 14

Discuss the formation and purpose of the septum primum

Answer 14

Septum Primum

crescent-shaped membranous ingrowth that sits posteriorly between the R & L atria and partially separates them; the ostium primum is the remaining anterior opening that allows movement of blood from the R to L atrium during fetal development

The septum primum completely obliterates the ostium primum before growing, developing a second posterior opening: ostium secundum

Question 15

Discuss the formation and purpose of the septum secundum

Answer 15

Septum secundum: subsequent membranous ingrowth located to the R and ant. of the septum primum

as the septum secundum grows, it leaves a small opening– foramen ovale– that is continuous with the ostium secundum; these structures permit continued L → R shunting of blood during intrauterine development

SS continues to enlarge until it forms a flap of tissue that covers the foramen ovale on its L side

Question 16

Describe the two different types of ASD in regards to prevalence and location

Answer 16

classified according to their location

Secundum ASD (90% of all ASD)

• deficient septum secundum formation near center of atrial septum

Primum anomalies (5% ASD)

• occur adjacent to AV valves
• often associated with AV valve anomalies and VSD

Sinus Venosus defects (5%)

• located near the entrance of the SVC
• can be associated with anomalous pulmonary venous return to the right atrium

Question 17

When do Atrial Septal Defect patients usually present?

Answer 17

Usually do not become symptomatic until ~30 y/o

Question 18

In Atrial Septal Defect patients, does pulmonary blood flow increase or decrease and by how much?

Answer 18

pulmonary blood flow 2-8X normal

Question 19

We see an interesting shunt pattern in Eisenmerger Syndrome. What is it?

Answer 19

Eventually the L→ R shunt becomes a R→ L shunt b/c pulmonary vascular resistance approaches systemic levels introducing poorly oxygenated blood into systemic circulation

Question 20

In Ventricular septal defects, where do we see the issues in the IV septum?

Answer 20

~90% are membranous (occur in the region of the membranous interventricular septum

~10% are infundibular (occur below the pulmonary valve or within the muscular septum)

Question 21

Describe the normal pattern and use of the Ductus Arteriosus

Answer 21

During intrauterine life, the DA permits blood flow from the pulmonary artery to the aorta, bypassing the lungs.

Shortly after birth, the DA should constrict and become functionally closed (becoming the ligamentum arteriosum)

Question 22

PDA produces this kind of murmur

Answer 22

PDA produces a characteristic continuous harsh “machinery-like” murmur

Question 23

3 y/o male with cyanosis (progressive since 6 months of age)

clubbing of fingers and toes
gray sclerae, dusky blue skin surfaces

Auscultation: pulmonary systolic ejection murmur

Thinking what?

Answer 23

Tetralogy of Fallot

Question 24

5 T’s of Cyanotic Congenital Heart Malformations

Answer 24

1. Tetralogy of Fallot
2. Transposition of the Great Vessels
3. Tricuspid Atresia
4. Truncus Arteriosus
5. TAPVR: total anomalous pulmonary venous return

Question 25

Midsystolic click makes us think what?

Answer 25

Mitral Valve Prolapse

Question 26

When does cyanosis present with Tetralogy of Fallot?

Answer 26

Most infants are cyanotic at birth

Question 27

Three types of aortic atresia and what they indicate

Answer 27

Valvular - cusps may be hypoplastic, dysplastic, or abnormal in number

Subvalvular - subaortic stenosis is caused by a thickened ring of dense endocardial fibrous tissue

Supravalvular - aortic dysplasia with thickening of ascending aortic wall and luminal constriction

Question 28

This type of atresia is associated with a chromosome 7 deletion

Answer 28

Supravalvular

Question 29

Symptoms indicated for Supravalvular Atresia

Answer 29

other symptoms are hypercalcemia, cognitive abnormalities, and facial anomalies (Williams-Beuren syndrome)

Question 30

This atresia is associated with a prominent systolic murmur

Answer 30

Subvalvular

Question 31

____ is the most common cause of rhythm disorders

Answer 31

Ischemia is the most common cause of rhythm disorders

Question 32

How do we characterize right sided hypertensive heart disease?

Answer 32

Characterized by right ventricular hypertrophy (chronic cor pulmonale), dilation (acute cor pulmonale) and eventually right-sided failure

Question 33

Hypertrophied right ventricle can sometimes compress the ___ ___ or lead to what?

Answer 33

Hypertrophied right ventricle can sometimes compress the left ventricular chamber or lead to regurgitation and fibrous thickening of tricuspid valve

Question 34

Obstruction to left ventricular outflow eventually leads to what?

Answer 34

Obstruction to left ventricular outflow eventually leads to gradual narrowing of the valve orifice and an increasing pressure gradient across the valve

Question 35

Defects that can cause Bicuspid Aortic Valve

Answer 35

Three loci on chromosomes 18q, 5q, 13q

Loss of function mutation in NOTCH1

Question 36

BAV predisposes to calcification, leading to increased risk for aortic stenosis & regurgitation, infective endocarditis, and aortic dilation and/or dissection

Answer 36

BAV predisposes to calcification, leading to increased risk for aortic stenosis & regurgitation, infective endocarditis, and aortic dilation and/or dissection

Question 37

What is mitral annular calcification’s effect on valvular function?

Answer 37

Does not usually affect valvular function

Question 38

Characteristic of Mitral Valve Prolapse

Answer 38

Characteristic change is interchordal ballooning (hooding) of the mitral leaflets

Question 39

What endocarditis is associated with Lupus and what exactly is it?

Answer 39

Endocarditis of Systemic Lupus Erythematosus (Libman-Sacks Disease)

Mitral and tricuspid valvulitis with small, sterile vegetations found in SLE

Question 40

Great treatment for Libman-Sacks Disease

Answer 40

Use of steroids has greatly reduced its occurrence

Question 41

What structurally occurs in the heart with someone with Libman-Sacks Disease

Answer 41

Lesions are small, may occur on undersurfaces of AV valves, valvular endocardium, on chords, or on mural endocardium of atria or ventricles

Question 42

Carcinoid Heart Disease? What symptoms do we see?

Answer 42

Refers to a systemic disorder marked by flushing, diarrhea, dermatitis, and bronchoconstriction that is caused by bioactive compounds such as serotonin released by carcinoid tumors

Question 43

Types of valve replacements

Answer 43

Mechanical valves - rigid, nonphysiologic material

Tissue valves (bioprostheses) - porcine aortic valves or bovine pericardium, frozen human valves from deceased donors (“homografts”)

Question 44

~60% of recipients of new valves develop a serious related problem within 10 years after surgery. Complications include:

Answer 44

1. Thromboembolism
2. Structural deterioration
3. Infective endocarditis
4. Paravalvular leak

Question 45

Primary vs. Secondary cardiomyopathy

Answer 45

Primary = genetic or acquired diseases of myocardium

Secondary = myocardial involvement as a component of a systemic or multiorgan disorder

Question 46

Three factors have contributed to the improved outcome of transplantations:

Answer 46

More effective immunosuppressive therapy (including cyclosporin A, glucocorticoids)

Careful selection of transplant candidates

Early histopathologic diagnosis of acute allograft rejection by endomyocardial biopsy