Cardiac pathology Part 2 Endocarditis & cardiomyopathies

Question 1

How does Streptococci viridians cause endocarditis? (aka describe the pathogenesis)

Answer 1

It has low virulence so it can only infect valves that have been damaged previously. It grows vegetations (fibrin & platelets) on valves which then trap more bacteria (because the state of bacteremia) causing further inflammation.

Question 2

How would you treat bacterial endocarditis in a patient with +ve blood cultures & a history of Chronic rheumatic heart disease?

Answer 2

Patient will have damaged valves from the CRHD,

Causal agent: S. viridians

Rx: prophylactic antibiotics

Question 3

What is the most common cause of bacterial endocarditis (excluding IV drug abusers)

Answer 3

S. viridians

Question 4

What is the most common cause of bacterial endocarditis in patients who abuse IV drugs?

Answer 4

S. aureus

Question 5

How does S. aureus cause endocarditis? (aka describe the pathogenesis)

Answer 5

It is very virulent so it is able to infect healthy valves (especially the tricuspid valve) it causes large vegetations which destroy the valves (acute endocarditis)

Question 6

How does S. epidermidis cause endocarditis?

Answer 6

It infects prostatic valves

Question 7

Endocarditis of prostatic valves is due to which organism?

Answer 7

S. epidermidis

Question 8

What causes endocarditis in patients with colorectal cancer?

Answer 8

S. bovis

Question 9

How does S. bovis cause endocarditis?

Answer 9

It infects the heart valves of patients with colorectal cancer

Question 10

What are the HACEK organisms that cause endocarditis with -ve blood cultures?

Answer 10

Hemophilus
Actinobacillus
Cardio bacterium
Eikenella
Kingella

Question 11

Hemophilus
Actinobacillus
Cardio bacterium
Eikenella
Kingella

Cause endocarditis with which unique feature?

Answer 11

Endocarditis with -ve blood cultures

Question 12

What are the signs of endocarditis (common to all)

Answer 12

1. Fever
2. Janeway lesions (painless palmar/soles)
3. Osler’s nodes (painful fingers)
4. Splinter hemorrhages.
5. Roth spots (embolization)
6. Anemia of chronic disease

Question 13

A 54-year-old male presents to the emergency department complaining of fever, fatigue, and shortness of breath that have progressively worsened over the past two weeks. He has a history of intravenous drug use, specifically heroin, but hasn’t used intravenously for the past six months. On physical examination, the patient appears ill and febrile with a temperature of 39.2°C (102.6°F), heart rate of 110 beats per minute, and blood pressure of 120/80 mmHg. Auscultation reveals a new-onset systolic murmur.

Answer 13

Bacterial endocarditis due to an infection with S. aureus

Question 14

A 62-year-old male with a history of mitral valve prolapse and prior dental procedures presents to the clinic with a complaint of fatigue, low-grade fever, and weight loss over the past few weeks. He reports experiencing episodes of chills and night sweats. On examination, there are multiple small petechiae over the conjunctiva and nail beds. Auscultation reveals a new-onset diastolic murmur.

Answer 14

Bacterial endocarditis due to S. viridians

Question 15

A 45-year-old male with a history of intravenous drug use presents to the emergency department with a chief complaint of fever, fatigue, and a new-onset heart murmur. He also reports night sweats and weight loss over the past month. On examination, multiple painful, erythematous nodules are found on his fingers. Laboratory tests reveal elevated inflammatory markers and blood cultures are ordered.

Answer 15

Bacterial endocarditis due to S. aureus

Question 16

What are the lab values to look out for when dealing with bacterial endocarditis?

Answer 16

1. +ve blood cultures (except HACEK)
2. Anemia of chronic disease (low Hb, TIBC, serum Fe, O2 saturation & high ferritin)

Question 17

Describe the pathogenesis of Non-Bacterial Thrombotic Endocarditis

Answer 17

It causes sterile vegetations that appear during states of hypercoagulability or adenocarcinomas

Question 18

Where do the vegetations arise in Non-Bacterial Thrombotic Endocarditis? What is a complication as a result of this?

Answer 18

Usually the mitral valve along the lines of closure which inhibit valve closure resulting in mitral regurgitation

Question 19

Describe the pathogenesis of Libman-Sacks endocarditis?

Answer 19

It is associated with SLE. It forms sterile vegetations on the surface/underside of the mitral valve resulting in mitral regurgitation/insufficiency

Question 20

A 55-year-old female with a history of advanced ovarian cancer presents to the clinic with complaints of headache, fatigue, and recurrent episodes of transient ischemic attacks (TIAs). The patient reports experiencing small, painful reddish-purple lesions on her palms and soles. Physical examination reveals a new-onset mitral valve murmur and bilateral retinal emboli.

Answer 20

non-bacterial thrombotic endocarditis due to ovarian cancer.

Question 21

A 35-year-old female with a known history of systemic lupus erythematosus (SLE) presents to the clinic with complaints of fatigue, shortness of breath, and occasional chest pain. She reports a low-grade fever over the past few weeks and has noticed swelling in her hands and feet. On examination, there is a malar rash, bilateral joint tenderness, and a high-pitched diastolic murmur at the apex of her heart.

Answer 21

Libman-sacks non-bacterial endocarditis

Question 22

Massive hypertrophy of the left ventricle due to an AUTO DOM mutation in the sarcomere proteins

Describes what type of cardiomyopathy?

Answer 22

Hypertrophic cardiomyopathy

Question 23

What are the signs of hypertrophic cardiomyopathy?

Answer 23

Decreased cardiac output with diastolic dysfunction (poor ventricular filling) due to the hypertrophy of the left ventricle

Question 24

What is the major cause of death due to hypertrophic cardiomyopathy?

Answer 24

It can cause sudden death due to ventricular arrythmia, it can even happen in young athletes!

Question 25

What are the signs of hypertrophic cardiomyopathy?

Answer 25

Syncope with exercise

Question 26

What are the changes to the aorta in patients with hypertrophic cardiomyopathy?

Answer 26

Subaortic hypertrophy of the ventricular septum results in functional aortic stenosis

Question 27

What would a biopsy of a patient with hypertrophic cardiomyopathy cause?

Answer 27

Myofiber hypertrophy with disarray

Question 28

A 45-year-old male presents to the clinic with complaints of shortness of breath, chest pain, and lightheadedness during physical activity. He mentions a family history of sudden cardiac death and recalls episodes of palpitations. On examination, his blood pressure is normal, but a harsh systolic murmur is heard best at the left lower sternal border that increases with the Valsalva maneuver and decreases with squatting

Answer 28

Hypertrophic cardiomyopathy causing functional aortic stenosis

Question 29

Describe what dilated cardiomyopathy is?

Answer 29

The most common cardiomyopathy, it’s when the heart wall is weak it is unable to pump blood out effectively (Systolic dysfunction).

As a result there is less filling & stretching of the heart chambers leading to biventricular heart failure & complications such as mitral/tricuspid valve regurgitation & arrythmia (stretched conduction systems)

Question 30

What are the causes of Dilated cardio myopathy?

Most common
Other

Answer 30

Most common:
- AUTO DOM mutations effecting the myocardium

Other:
- Infections with Coxsackie A or B (myocarditis)

• Alcohol abuse
• Pregnancy (late preg or post birth)
• Drugs (Doxorubicin & cocaine)

Question 31

How do you treat dilated cardiomyopathy?

Answer 31

Heart transplant

Question 32

A 55-year-old female comes to the emergency room complaining of worsening shortness of breath and fatigue for the past few months. She reports having difficulty doing her daily activities, such as climbing stairs or walking short distances, without feeling extremely tired. She also experienced sudden weight gain and noticed swelling in her ankles and legs. On examination, her blood pressure is low, heart rate is elevated, and her jugular veins are visibly distended. Auscultation reveals a rapid and irregular heartbeat, along with a third heart sound.

What’s the diagnosis & treatment?

Answer 32

Dilated cardiomyopathy & treatment is a heart transplant

Question 33

What is restrictive cardiomyopathy?

Answer 33

There’s a decrease in ventricular endomyocardial compliance that restricts filling during diastole

Question 34

What are the signs of restrictive cardiomyopathy?

Answer 34

1. CHF (pulmonary edema/dyspnea)
2. Low-voltage ECK with diminished QRSs amplitude (less filling)

Question 35

1. CHF (pulmonary edema/dyspnea)
2. Low-voltage ECK with diminished QRSs amplitude (less filling)

Are signs of which type of cardiomyopathy?

Answer 35

Restrictive cardiomyopathy

Question 36

What are the causes of restrictive cardiomyopathy?

Answer 36

Amyloidosis
Sarcoidosis
Endocardial fibroelastosis (children)
Loeffler syndrome
Hemochromatosis

Question 37

Endocardial fibroelastosis (dense fibrosis & elastic tissue in endocardium children) can cause which cardiomyopathy?

Answer 37

Restrictive cardiomyopathy

Question 38

What is a Myxoma?

Answer 38

A benign cardiac tumor (adults) made from mesenchymal cells. It has a gelatinous appearance (because of abundant ground substance)

Question 39

A mesenchymal cardiac tumor with a gelatinous appearance. What’s the tumor? Why is it gelatinous?

Answer 39

A myxoma it’s gelatinous because of the abundant ground substance

Question 40

What is the cause & signs of a Myoma?

Answer 40

usually caused by a pedunculated mass in the left atrium that obstructs the mitral valve resulting in symptoms like syncope

Question 41

Syncope due to mitral valve obstruction - what’s the tumor?

Answer 41

Myxoma

Question 42

What is a Rhabdomyoma?

Answer 42

A benign hamartoma more common in children. It usually manifests in the ventricle & it’s associated with a TB infection

Question 43

Cardiac tumor associated with TB - What’s the tumor?

Answer 43

Rhabdomyoma

Question 44

What are metastasis involving the heart? What other organs do they typically involve?

Answer 44

Metastasis tend to involve the pericardium which can result in pericardial effusion

Other organs involved are usually: skin/lymph, breast, & lungs