Cardiovascular - Pathology (1) Flashcards
1
Q
Congenital heart diseases:
Right-to-left shunts
- Characteristic findings
- Diseases
A
- Characteristic findings
- Early cyanosis
- “Blue babies.”
- Often diagnosed prenatally or become evident immediately after birth.
- Usually require urgent surgical correction and/or maintenance of a PDA.
- Diseases (The 5 Ts)
- Truncus arteriosus (1 vessel)
- Transposition (2 switched vessels)
- Tricuspid atresia (3 = Tri)
- Tetralogy of Fallot (4 = Tetra)
- TAPVR (5 letters in the name)
2
Q
Persistent truncus arteriosus
- Type of disease
- Characteristics
A
- Type of disease
- Right-to-left shunt congenital heart disease
- Characteristics
- Failure of truncus arteriosus to divide into pulmonary trunk and aorta
- Most patients have accompanying VSD.
3
Q
D-transposition of great vessels
- Type of disease
- Characteristics
A
- Type of disease
- Right-to-left shunt congenital heart disease
- Characteristics
- Aorta leaves RV (anterior) and pulmonary trunk leaves LV (posterior) –> separation of systemic and pulmonary circulations.
- Not compatible with life unless a shunt is present to allow mixing of blood (e.g., VSD, PDA, or patent foramen ovale).
- Due to failure of the aorticopulmonary septum to spiral.
- Without surgical intervention, most infants die within the first few months of life.
4
Q
Tricuspid atresia
- Type of disease
- Characteristics
A
- Type of disease
- Right-to-left shunt congenital heart disease
- Characteristics
- Absence of tricuspid valve and hypoplastic RV
- Requires both ASD and VSD for viability.
5
Q
Tetralogy of Fallot
- Type of disease
- Characteristics
A
- Type of disease
- Right-to-left shunt congenital heart disease
- Characteristics
- Caused by anterosuperior displacement of the infundibular septum.
- Most common cause of early childhood cyanosis.
- Tetralogy: PROVe
- Pulmonary infundibular stenosis (most important determinant for prognosis)
- RVH—boot-shaped heart on CXR
- Overriding aorta
- VSD
- Pulmonary stenosis forces right-to-left flow across VSD –> early cyanotic “tet spells,” RVH.
- Squatting: increased SVR, decreased right-to-left shunt, improves cyanosis.
- Treatment: early surgical correction.
6
Q
Total anomalous pulmonary venous return (TAPVR)
- Type of disease
- Characteristics
A
- Type of disease
- Right-to-left shunt congenital heart disease
- Characteristics
- Pulmonary veins drain into right heart circulation (SVC, coronary sinus, etc.)
- Associated with ASD and sometimes PDA to allow for right-to-left shunting to maintain CO.
7
Q
Congenital heart diseases:
Left-to-right shunts
- Characteristic findings
- Diseases
A
- Characteristic findings
- Late cyanosis
- “Blue kids.”
- Diseases
- Frequency: VSD > ASD > PDA
- Ventricular septal defect (VSD)
- Atrial septal defect (ASD)
- Patent ductus arteriosus (PDA)
- Eisenmenter syndrome
- Frequency: VSD > ASD > PDA
8
Q
Ventricular septal defect
- Type of disease
- Characteristics
A
- Type of disease
- Left-to-right shunt congenital heart disease
- Characteristics
- Most common congenital cardiac defect.
- Asymptomatic at birth, may manifest weeks later or remain asymptomatic throughout life.
- Most self resolve
- Larger lesions may lead to LV overload and heart failure.
9
Q
Atrial septal defect
- Type of disease
- Characteristics
A
- Type of disease
- Left-to-right shunt congenital heart disease
- Characteristics
- Defect in interatrial septum
- Loud S1
- Wide, fixed split S2.
- Usually occurs in septum secundum
- Septum primum defects usually occur with other anomalies.
- Symptoms range from none to heart failure.
- Distinct from patent foramen ovale in that septa are missing tissue rather than unfused.
- Defect in interatrial septum
10
Q
Patent ductus arteriosus
- Type of disease
- Characteristic findings
A
- Type of disease
- Left-to-right shunt congenital heart disease
- Characteristic findings
- In fetal period, shunt is right to left (normal).
- In neonatal period, decreased lung resistance –> shunt becomes left to right –> progressive RVH and/or LVH and heart failure.
- Associated with a continuous, “machine-like” murmur.
- Patency is maintained by PGE synthesis and low O2 tension.
- “Endomethacin” (indomethacin) ends patency of PDA
- PGE** kEEps it open (may be necessary to sustain life in conditions such as transposition of the great vessels).**
- Uncorrected PDA can eventually result in late cyanosis in the lower extremities (differential cyanosis).
- PDA is normal in utero and normally closes only after birth.
11
Q
Eisenmenger syndrome
- Type of disease
- Characteristics
A
- Type of disease
- Left-to-right shunt congenital heart disease
- Characteristics
- Uncorrected left-to-right shunt (VSD, ASD, PDA)
- –> increased pulmonary blood flow
- –> pathologic remodeling of vasculature
- –> pulmonary arteriolar hypertension.
- RVH occurs to compensate –> shunt becomes right to left.
- Causes late cyanosis, clubbing, and polycythemia.
- Age of onset varies.
- Uncorrected left-to-right shunt (VSD, ASD, PDA)
12
Q
Coarctation of the aorta
- Associated with…
- Infantile type
- Adult type
A
- Associated with bicuspid aortic valve, other heart defects.
- Infantile type
- Aorta narrowing is proximal to insertion of ductus arteriosus (preductal).
- Infantile: in close to the heart.
- Associated with Turner syndrome.
- Can present with closure of the ductus arteriosus (reverse with PGE2).
- Aorta narrowing is proximal to insertion of ductus arteriosus (preductal).
-
Adult type
- Aorta narrowing is distal to ligamentum arteriosum (postductal).
- Adult: distal to ductus.
- Associated with notching of the ribs (collateral circulation), hypertension in upper extremities, and weak, delayed pulses in lower extremities (radiofemoral delay).
- Aorta narrowing is distal to ligamentum arteriosum (postductal).
13
Q
Defects associated with these congenital cardiac disorders
- 22q11 syndromes
- Down syndrome
- Congenital rubella
- Turner syndrome
- Marfan syndrome
- Infant of diabetic mother
A
- 22q11 syndromes
- Truncus arteriosus
- Tetralogy of Fallot
- Down syndrome
- ASD
- VSD
- AV septal defect (endocardial cushion defect)
- Congenital rubella
- Septal defects
- PDA
- Pulmonary artery stenosis
- Turner syndrome
- Bicuspid aortic valve
- Coarctation of aorta (preductal)
- Marfan syndrome
- MVP
- Thoracic aortic aneurysm and dissection
- Aortic regurgitation
- Infant of diabetic mother
- Transposition of great vessel
14
Q
Hypertension
- Definition
- Risk factors
- Features
- Predisposes to…
A
- Definition
- A systolic BP ≥ 140 mmHg and/or diastolic BP ≥ 90 mmHg
- Risk factors
- Increased age
- Obesity
- Diabetes
- Smoking
- Genetics
- Black > white > Asian.
- Features
- 90% of hypertension is 1° (essential) and related to increased CO or increased TPR
- Remaining 10% mostly 2° to renal disease, including fibromuscular dysplasia in young patients [A].
- Hypertensive emergency—severe hypertension (≥ 180/120 mmHg) with evidence of acute, ongoing target organ damage (e.g., papilledema, mental status changes).
- Predisposes to…
- Atherosclerosis
- LVH
- Stroke
- CHF
- Renal failure [B]
- Retinopathy
- Aortic dissection.
15
Q
Hyperlipidemia signs
A
- Xanthomas
- Plaques or nodules composed of lipid-laden histiocytes in the skin [A], especially the eyelids (xanthelasma [B]).
- Tendinous xanthoma
- Lipid deposit in tendon [C], especially Achilles.
- Corneal arcus
- Lipid deposit in cornea, appears early in life with hypercholesterolemia.
- Common in elderly (arcus senilis [D]).
16
Q
Arteriosclerosis
- Mönckeberg (medial calcific sclerosis)
- Arteriolosclerosis
A
- Mönckeberg (medial calcific sclerosis)
- Uncommon.
- Calcification in the media of the arteries, especially radial or ulnar.
- Usually benign
- “Pipestem” arteries on x-ray [A].
- Does not obstruct blood flow
- Intima not involved.
- Arteriolosclerosis
- Common.
- Two types:
- Hyaline (thickening of small arteries in essential hypertension or diabetes mellitus [B])
- Hyperplastic (“onion skinning” as seen in severe hypertension [C]).
17
Q
Atherosclerosis
- Definition
- Risk factors
- Modifiable
- Non-modifiable
- Progression
- Complications
- Location
- Symptoms
A
- Definition
- Disease of elastic arteries and large- and medium-sized muscular arteries.
- Risk factors
- Modifiable: smoking, hypertension, hyperlipidemia, diabetes.
- Non-modifiable: age, sex (increased in men and postmenopausal women), and family history.
- Progression
- Inflammation important in pathogenesis.
- Endothelial cell dysfunction –> macrophage and LDL accumulation –> foam cell formation –> fatty streaks –> smooth muscle cell migration (involves PDGF and FGF), proliferation, and extracellular matrix deposition –> fibrous plaque –> complex atheromas [A].
- Complications
- Aneurysms, ischemia, infarcts, peripheral vascular disease, thrombus, emboli.
- Location
- Abdominal aorta > coronary artery > popliteal artery > carotid artery [B].
- Symptoms
- Angina, claudication, but can be asymptomatic.
18
Q
Aortic aneurysms
- Definition
- Abdominal aortic aneurysm
- Thoracic aortic aneurysm
A
- Definition
- Localized pathologic dilation of the aorta.
- May cause pain, which is a sign of leaking, dissection, or imminent rupture.
- Abdominal aortic aneurysm
- Associated with atherosclerosis.
- Occurs more frequently in hypertensive male smokers > 50 years old [A].
- Thoracic aortic aneurysm
- Associated with cystic medial degeneration due to hypertension (older patients) or Marfan syndrome (younger patients).
- Also historically associated with 3° syphilis (obliterative endarteritis of the vasa vasorum) [B].
19
Q
Aortic dissection
A
- Longitudinal intraluminal tear forming a false lumen [A].
- Associated with hypertension, bicuspid aortic valve, and inherited connective tissue disorders (e.g., Marfan syndrome).
- Can present with tearing chest pain, of sudden onset, radiating to the back +/- markedly unequal BP in arms.
- CXR shows mediastinal widening.
- The false lumen can be limited to the ascending aorta, propagate from the ascending aorta, or propagate from the descending aorta.
- Can result in pericardial tamponade, aortic rupture, and death.
26
Q
Evolution of MI:
4-12 hr
- Gross
- Light microscope
- Complications
A
- Gross
- Occluded artery
- Infarct
- Dark mottling
- Pale with tetrazolium stain
- Light microscope
- Early coagulative necrosis, release of necrotic cell contents into blood
- Edema, hemorrhage, wavy fibers.
- Complications
- Arrhythmia, HF, cardiogenic shock, death.
27
Q
Evolution of MI:
12–24 hr
- Gross
- Light microscope
- Complications
A
- Gross
- Occluded artery
- Infarct
- Dark mottling
- Pale with tetrazolium stain
- Light microscope
- Neutrophil migration starts.
- Reperfusion injury may cause contraction bands (due to free radical damage).
- Complications
- Arrhythmia, HF, cardiogenic shock, death.
28
Q
Evolution of MI:
1–3 days
- Gross
- Light microscope
- Complications
A
- Gross
- Hyperemia
- Light microscope
- Extensive coagulative necrosis.
- Tissue surrounding infarct shows acute inflammation with neutrophils.
- Complications
- Fibrinous pericarditis.
29
Q
Evolution of MI:
3–14 days
- Gross
- Light microscope
- Complications
A
- Gross
- Hyperemic border
- Central yellow-brown softening
- Maximally yellow and soft by 10 days
- Light microscope
- Macrophages, then granulation tissue at margins.
- Complications
- Free wall rupture –> tamponade
- Papillary muscle rupture –> mitral regurgitation
- Interventricular septal rupture due to macrophage-mediated structural degradation.
- LV pseudoaneurysm (mural thrombus “plugs” hole in myocardium –> “time bomb”).
30
Q
Evolution of MI:
2 weeks to several months
- Gross
- Light microscope
- Complications
A
- Gross
- Recanalized artery
- Gray-white
- Light microscope
- Contracted scar complete.
- Complications
- Dressler syndrome, HF, arrhythmias, true ventricular aneurysm (outward bulge during contraction, “dyskinesia”).
31
Q
Diagnosis of MI
- Gold standard
- Cardiac troponin I
- CK-MB
- ECG changes
A
- In the first 6 hours, ECG is the gold standard.
- Cardiac troponin I
- Rises after 4 hours
- Increased for 7–10 days
- More specific than other protein markers.
- CK-MB
- Predominantly found in myocardium but can also be released from skeletal muscle.
- Useful in diagnosing reinfarction following acute MI because levels return to normal after 48 hours.
- ECG changes
- ST elevation (STEMI, acute transmural infarct)
- ST depression (subendocardial infarct)
- Pathologic Q waves (evolving or old transmural infarct).
