Summaries Chapter 11: The Heart

Question 1

What is ischemic heart disease?

Answer 1

Heart problems caused by narrowed heart arteries

Question 2

What is, in the majority of the cases, the cause of cardiac ischemia?

Answer 2

Coronary artery atherosclerosis

Question 3

What is, in the minority of the cases, the cause of cardiac ischemia?

Answer 3

Vasospasm, vasculitis, and embolism

Question 4

Cardiac ischemia results from a mismatch between coronary supply and myocardial demand and manifests as different, albeit overlapping syndromes. Name all 5 of them

Answer 4

• Angina pectoris
• Unstable angina
• Acute myocardial infarction
• Sudden cardiac death
• Ischemic cardiomyopathy

Question 5

What is Angina Pectoris?

Answer 5

Angina pectoris is exertional chest pain due to inadequate
perfusion, and is typically due to atherosclerotic disease causing greater than 70% fixed stenosis (so-called “critical stenosis”).

Question 6

What is unstable angina?

Answer 6

Unstable angina is characterized by increasingly frequent pain, precipitated by progressively less exertion or even occurring at rest. It results from an erosion or rupture of atherosclerotic plaque triggering platelet aggregation, vasoconstriction, and formation of a mural thrombus that need not necessarily be occlusive.

Question 7

What is acute myocardial infarction?

Answer 7

Acute myocardial infarction typically results from acute thrombosis after plaque disruption; a majority occur in plaques that did not previously exhibit critical stenosis.

Question 8

What is sudden cardiac death?

Answer 8

Sudden cardiac death usually results from a fatal arrhythmia, typically without significant acute myocardial damage.

Question 9

What is ischemic cardiomyopathy?

Answer 9

Ischemic cardiomyopathy is progressive heart failure due to ischemic injury, either from previous infarction(s) or chronic ischemia.

Question 10

Myocardial ischemia leads to loss of myocyte function within…

Answer 10

1 to 2 minutes

Question 11

Myocardial ischema leads to death after…

Answer 11

30-40 minutes

Question 12

How is myocardial infarction diagnosed?

Answer 12

On the basis of symptoms, electrocardiographic changes, and measurement of serum biomarkers such as cardiac-specific troponins

Question 13

Why are gross and histologic changes not used for the diagnosis of myocardial infarction?

Answer 13

Because they take days to develop (and the patient doesn’t have days)

Question 14

How can infarction be modified/treated?

Answer 14

By therapeutic intervention (e.g., thrombolysis or stenting), which salvages myocardium at risk but may also induce reperfusion-related injury.

Question 15

What are complications of infarction?

Answer 15

Complications of infarction include ventricular rupture, papillary muscle rupture, aneurysm formation, mural thrombus, arrhythmia, pericarditis, and CHF.

Question 16

Valve pathology can lead to occlusion and/or regurgitation. What does occlusion mean here?

Answer 16

Stenosis

Question 17

Valve pathology can lead to occlusion and/or regurgitation. What does regurgitation mean here?

Answer 17

Insufficiency

Question 18

Acquired aortic or mitral valve stenosis accounts for … (like how many?) of all valve disease

Answer 18

2/3

Question 19

What does valve calcification typically result in?

Answer 19

Stenosis

Question 20

What does abnormal matrix synthesis and turnover lead to?

Answer 20

Myxomatous degeneration and insufficiency

Question 21

Inflammatory valve diseases cause …

Answer 21

Postinflammatory neovascularization and scarring

Question 22

What does rheumatic heart disease result from?

Answer 22

Anti-streptococcal antibodies that cross-react with cardiac tissues

Question 23

Which valve is often affected in rheumatic heart disease?

Answer 23

The mitral valve (and is responsible for almost all cases of acquired mitral stenosis!)

Question 24

True/false: Infective endocarditis rapidly destroys normal valves

Answer 24

It can, not per definition. It can also be indolent and minimally destructive or previously abnormal valves

Question 25

What can systemic embolization produce/cause?

Answer 25

Septic infarct

Question 26

How does nonbacterial thrombotic endocarditis occur and where?

Answer 26

Nonbacterial thrombotic endocarditis occurs on previously normal valves as a result of hypercoagulable states

Question 27

What is an important complication of nonbacterial thrombotic endocarditis?

Answer 27

Embolization

Question 28

What does cardiomyopathy refer to?

Answer 28

Intrinsic cardiac muscle disease; there may be specific causes, or it may be idiopathic

Question 29

What are the three general pathophysiologic categories of cardiomyopathy?

Answer 29

• dilated (90%)
• hypertrophic
• restrictive (least common)

Question 30

What does DCM (dilated cardiomyopathy) result in?

Answer 30

Systolic (contractile) dysfunction

Question 31

What does HCM (hypertrophic cardiomyopathy) result in?

Answer 31

Diastolic (relaxation) dysfunction

Question 32

What does RCM (restrictive cardiomyopathy) result in?

Answer 32

Stiff, noncomplaint mycardium

Question 33

What are causes of HCM?

Answer 33

Virtually all cases are due to autosomal dominant mutations in the proteins that make up the contractile apparatus, in particular β-myosin heavy chain.

Question 34

What are causes of DCM?

Answer 34

Myocarditis, toxic exposures (e.g., alcohol), and pregnancy. In 20% to 50% of cases, mutations affecting cytoskeletal proteins are responsible

Question 35

What are causes of RCM?

Answer 35

Can be due to depositions (e.g. amyloid), increased interstitial fibrosis (e.g. due to radiation), or endomyocardial scarring

Question 36

What is arrhythmogenic right ventricular cardiomyopathy?

Answer 36

Arrhythmogenic right ventricular cardiomyopathy is an autosomal dominant disorder of cardiac muscle that manifests with right-sided heart failure and rhythm disturbances that can cause sudden cardiac death in athletes.

Question 37

What is myocarditis? (also explain cause/symptoms)

Answer 37

Myocarditis is an inflammatory disorder caused by infections or immune reactions. Coxsackieviruses A and B are the most common pathogens in the United States. Clinically, myocarditis may be asymptomatic, give rise to acute heart failure, or evolve to DCM.

Question 38

What are pericardial disease?

Answer 38

Pericardial disease, or pericarditis, is inflammation of any of the layers of the pericardium

Question 39

Pericarditis can occur primary or secondary, which is more uncommon?

Answer 39

Primary

Question 40

What are pericardial lesions typically are associated with?

Answer 40

A pathologic process elsewhere in the heart or surrounding structures, or are secondary to a systemic disorder