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Flashcards in Heart Deck (72):
1

What is an important complication of atherosclerosis?

HTN

2

What is arterial pressure dependent on? How is it regulated?

Primarily on the pumping of the heart
Regulated by hormones and biogenic amines

3

Congestive heart failure

Common end point of many cardiac diseases

4

Systolic CHF

Most CHF
Caused by deterioration of myocardial contractile function, resulting mainly from ischemic heart disease or htn

5

Diastolic CHF

Contraction is nl, but relaxation is abnl; mainly older women with htn or diabetes

6

Valve failure example

Endocarditis

7

How does the system initially respond to heart failure?

Activation of neurohumoral systems
-NE
-Renin-angiotensin-aldosterone system
-Atrial natriuretic peptide (ANP)
Frank-Starling mechanism
Hypertrophy

8

What happens when the compensatory mechanisms for CHF fail?

Myocytes degenerate
Heart needs more oxygen
Myocardium becomes vulnerable to ischemia

9

Systolic left-sided heart failure

LV does not pump enough blood to body

10

Diastolic left-sided heart failure

LV does not accept enough blood from lungs and LA

11

Clinical consequences of left-sided heart failure

Decreased cardiac output
-Activity intolerance and signs of decreased tissue perfusion
Pulmonary congestion
-Impaired gas exchange
--Cyanosis and signs of hypoxia
-Pulmonary edema
--Cough with frothy sputum
--Orthopnea
--Paroxysmal nocturnal dyspnea

12

Most common causes of left-sided heart failure

Ischemic heart disease (IHD)
Systemic htn
Mitral or aortic valve disease
Primary diseases of the myocardium

13

Heart changes in left-sided heart failure

LV usually hypertrophied and dilated
Secondary enlargement of LA with afib may lead to reduced stroke volume, blood stasis and thrombus formation

14

Right-sided heart failure

RV fails, blood backs up in the body

15

Most common cause of right-sided heart failure

Left-sided heart failure
-Pressure increased in the pulmonary circulation produces increased burden on right side of the heart

16

Heart changes in right-sided heart failure

RV and atrium hypertrophied and dilated

17

Examples of right-sided heart failure

Disease of lung parenchyma and/or lung vasculature; cor pulmonale
Pulmonic or triscupid valve disease
Congenital heart diseases with left-to-right shunt

18

Diastolic right-sided heart failure

RV does not accept enough blood from body and RA

19

Systolic right-sided failure

RV does not pump enough blood to lungs

20

Clinical consequences of right-sided heart failure

Congestion of peripheral tissues
-Dependent edema and ascites
-GI tract congestion
--Anorexia
--GI distress
--Weight loss
-Liver congestion
--Signs related to impaired liver function

21

Congenital heart disease

Abnormalities of heart/great vessels present from birth
Faulty embryogeneis, weeks 3-8

22

Left-to-right shunt examples

Most common; non-cyanotic
Atrial septal defects (ASDs)
Ventricular septal defects (VSDs)
Patent ductus arteriosus (PDA)

23

Right-to-left shunt examples

Cyanotic
Tetralogy of Fallot
Transposition of the great arteries (TGA)

24

Obstructions

Coarctation of aorta

25

Shunt

An abnormal communication between cardiac chambers or blood vessels. A shunt permits blood to flow between chambers or vessels that are normally isolated from each other

26

Right-to-left shunt

Pulmonary circulation is bypassed and poorly oxygenated blood enters systemic circulation causing cyanosis

27

Left-to-right shunt

Increases pulmonary blood flow increasing pressure and volume of pulmonary circulation, causing right ventricular hypertrophy

28

Obstructive congenital heart disease

Decreased vascular flow caused by narrowing (stenosis) or complete blockage or absence (atresia) of the heart chambers, valves, or major blood vessels

29

What do ASDs initially cause?

Left-to-right shunt, asymptomatic in most people

30

Are ASDs or VSDs less likely to close spontaneously?

ASDs

31

What is the result of ASD?

Pulmonary vascular resistance may increase (pulmonary htn), leading to right-to-left shunt (Eisenmenger syndrome)

32

What prevents irreversible pulmonary changes and heart failure?

Surgical repair

33

Ventricular Septal Defects (VSDs)

Most common CHD at birth
Most close spontaneously in childhood

34

What does a VSD result in?

Left-to-right shunt

35

Sx in small VSDs
Sx in large VSDs

Small: asymptomatic
Large: severe left-to-right shunt, may lead to Eisenmenger syndrome, with cyanosis and CHF; earlier, more often that with ASDs

36

What is required for large VSD lesions?

Surgical correction

37

Patent Ductus Arteriosus (PDA)

Closes spontaneously by day 1-2 of life
Ductus arteriosus permits blood to flow from pulmonary artery to aorta, bypassing lungs during fetal development
"Machinery-like" murmurs

38

Large PDA

Small is asymptomatic
Left-to-right shunt; may lead to Eisenmenger syndrome, with cyanosis and CHF

39

Tetralogy of Fallot

Right-to-left shunt

40

Four features of Tetralogy of Fallot

Large VSD
Aorta overrides the VSD
Obstruction to RV outflow tract
RV hypertrophy

41

Sx of tetralogy of Fallot

Cyanosis
Clubbing of fingertips
Polycythemia
Paradoxical emboli

42

Transposition of the Great Arteries (TGA)

Aorta arises from RV; pulmonary artery arises from LV
Atrium-to-ventricle connections are nl

43

Outcome of transposition of the great arteries

Separation of systemic and pulmonary circulations

44

Prognosis of transposition of the great arteries

Even with a stable shunt, most uncorrected TGA pts will die within first few months of life, so corrective usually performed within first few weeks of life

45

Coarctation of the aorta

Males affected twice as often as females
Preductal (infantile)- usually fatal without intervention
Postductal- usually asymptomatic

46

Sx of coarctation of aorta

Cyanosis and/or low bp in lower extremities

47

Ischemic heart disease (IHD)

Generic designation for a group of related syndromes resulting from MI
-Cardiac blood supply (perfusion) cannot meet myocardial oxygen demand

48

Cause of ischemic heart disease

Decreased coronary artery blood flow- CAD

49

Four basic clinical syndromes of ischemic heart disease

Angina pectoris
Acute MI
Chronic IHD
Sudden cardiac death

50

Angina pectoris

Intermittent chest pain caused by transient, reversible myocardial ischemia

51

Typical (stable) angina

Episodic pain on exertion
Narrowing (greater than or equal to 75%) of one or more coronary arteries

52

Prinzmetal (variant) angina

Pain at rest
Coronary artery spasm of unknown etiology

53

Unstable (crescendo) angina

Increasing pain with less exertion, longer duration
Plaque disruption and thrombosis

54

Process of MI

Most caused by acute coronary artery thrombosis
Sudden plaque disruption
Platelets adhere
Coagulation cascade activated
Thrombus occludes lumen within mins
Irreversible injury/cell death in 20-40 mins

55

How is reperfusion achieved following an acute MI?

Thrombolysis, balloon angioplasty, or coronary artery bypass graft

56

Clinical features of MI

Severe, crushing chest pain +/- radiation
Typically lasts 20 min to several hrs
Not significantly relieved by nitro or rest
Pulse is generally rapid and weak
Sweating, nausea, dyspnea
Cardiogenic shock can develop following massive MI (> 40% of LV)
Sometimes no sx (10-15%)

57

EKG abnormalities of MI

Q waves: transmural infarcts
ST-segment abnormalities and T-wave inversion: abnormalities in myocardial repolarization
Arrhythmias: electrical abnormalities of ischemic myocardium and conductance system
SCD due to lethal arrhythmias accounts for most deaths occurring before hospitalization

58

Complications of MI

Contractile dysfunction
Arrhythmias
Myocardial rupture
Pericarditis
Infarct expansion
Mural thrombus
Ventricular aneurysm
Papillary muscle dysfunction
Chronic progressive heart failure

59

Prognosis of MI

Depends on infarct size, site, and thickness of heart wall damage
Long-term prognosis especially dependent on the quality of left ventricular function and the extent of vascular obstruction in vessels that supply the remaining healthy myocardium

60

Sudden cardiac death (SCD)

Unexpected cardiac death from cardiac causes without sx (or within 24 hr of symptom onset)
Coronary atherosclerosis is most common cause

61

Cor pulmonale

RV is enlarged due to pulmonary htn caused by primary lung disorders

62

What does pressure overload cause?

Ventricular wall thickness

63

What does volume overload cause?

Ventricular wall dilation

64

Calcific aortic stenosis

MCC of aortic stenosis in US
Results in increased LV pressure, LV hypertrophy, and relative ischemia

65

Sx of calcific aortic stenosis

Angina
CHF
Fainting

66

Mitral valve prolapse sound

Midsystolic clicks

67

Risks of mitral valve prolapse

Increased risk for infective endocarditis and sudden death from ventricular arrhythmias

68

Rheumatic valvular disease

Systemic inflammatory disease occurring a few weeks after streptococcal pharyngitis; children 5-15 yrs

69

What does rheumatic heart disease cause?

Valve deformities, especially scarring and stenosis of the mitral valve, followed by damage to both mitral valve and aortic valve.

70

Pericarditis

Secondary, usual- acute MI, cardiac surgery, irradiation, pneumonia, uremia
Primary, very rare: mainly infection by viruses
Atypical chest pain, not related to exertion, often worse on reclining
Prominent friction rub
May cause cardiac tamponade

71

Types of pericardial effusions

Serous- CHF, hypoalbuminemia
Serosanguinous- blunt chest trauma, malignancy, rupture MI, aortic dissection
Chylous- mediastinal lymphatic obstruction

72

Pericardial effusion outcome

Depends on ability of pericardial sac to stretch, amount of fluid accumulated, and speed of accumulation
-Slow= asymptomatic
-Sudden = fatal cardiac tamponade