Cardio Pathology Part 1 Flashcards
How is dominance of the heart defined?
Defined due to the preference of the posterior descending artery
What happens as the heart ages?
There is a reduction in compliance and elasticity
What can happen to the mitral valve as the heart ages?
Become fibrous which will cause a buckling prolapse during systole leading to atrial dilation and arrhythmia
What do calcific deposits on the valves cause?
Aortic stenosis
How do the chambers of the heart change with age?
- Left ventricle cavity size reduced (esp in HTN)
- Atrial dilation
What atherosclerotic changes occur with age?
- Significant stenosis (MI, aortic dissection)
What epicardial and myocardial changes occur with age?
- Increase in epicardial fat
- Lipofuscin accumulates
- Basophilic degeneration
- Myocyte loss
- Amyloid deposition (transthyretin)
What are the two types of pump failure in cardiovascular dysfunction?
- Inadequate contraction (systole)
- Inadequate filling (diastole)
What does flow obstruction cause?
- Increase in resistance pressure (HTN, valve stenosis)
- Decreased blood flow (atherosclerosis; cardiac ischemia)
What causes regurgitant flow?
- Incompetent valve (valvular disease)
What causes shunted flow?
- Congenital disease (VSD, PDA)
- After MI
What can cause cardiac conduction abnormalities?
- Ischemic injury (infarction, direct nodal injury, dilated dysfunction)
- Heritable arrhythmias
What can cause vessel rupture?
- Aortic dissection
- Trauma (car crash from hitting chest on steering wheel)
What is a good approximation of heart weight?
- 0.5% of BW
What is the definition of dilation?
Enlarged chamber size
What is the definition of hypertrophy?
- Increase in muscle mass or thickening of heart muscle (due to cardiomyocyte size or length)
What is cardiomegaly?
- Abnormal enlargement of the heart (increase in weight or size)
What are some causes of hypertrophy or dilation? What causes this?
- HTN, Vascular disease, and MI
- Caused by increased cardiac work
What causes congestive heart failure?
- A pump failure which causes inadequate blood supply to the body
- Either a systolic dysfunction or a diastolic dysfunction)
What are some causes of systolic dysfunction?
- Decreased ejection fraction
- Ischemic injury
- Dilated cardiomyopathy
- Valve regurgitation
What are some causes of diastolic dysfunction?
- Will have normal EF but lower total volume due to less filling
- HTN
- Aortic stenosis
- Hypertrophic cardiomyopathy
- Fibrosis
- Restrictive cardiomyopathy
What are some primary causes of left sided CHF?
- MI
- HTN
- Left-sided valve disease
- Primary myocardial disease
What are the clinical effects of left sided CHF?
- Pulmonary congestion/edema
- Decreased tissue perfusion (decreased cerebral perfusion and decreased renal perfusion, azotemia)
What is seen on CXR in a patient with left sided CHF?
- Kerley B lines (like in pneumonia)
What is seen histologically in a patient with left sided CHF?
- Hemosiderin-laden macrophages
What is the most common cause of right sided CHF?
- Left sided failure
Why is left sided heart failure the number one cause of right sided failure?
- Increase in pulmonary pressure causes the right side to fail
What is isolated right heart failure called?
- Cor Pulmonale
What are some causes of pulmonary HTN?
- Parenchymal lung diseases (most common)
- Lung thromboemboli
- Primary pulmonary HTN (Rare)
What are some clinical effects due to venous congestion?
- Hepatosplenomegaly
- Distended jugular veins
- Effusions of peritoneal, pleural, and pericardial spaces
- Edema (esp ankles)
- Nutmeg liver
What are some causes of congenital heart disease?
- Sporadic genetic mutations (common)
- Environmental toxins (fetal alcohol syndrome)
What is the most common congenital heart defect in those with down syndrome?
- Atrioventricular or ventricular septal defects
What is the most common congenital heart defect in those with marfan syndrome?
- Aortic aneurysm/dissection
What is the mnemonic for DiGeorge Syndrome?
- CATCH-22
What are the most common congenital heart defects in those with DiGeorge syndrome?
- Conotruncal heart abnormalities
- ASD
- VSD
What is the most common congenital heart defect in those with Turner’s syndrome?
- Coarctation of the aorta
What are the most common congenital heart defects in those with Patau’s or Edward’s syndromes?
- PDA
- VSD
- ASD
What are the two types of cardiac shunts?
- L to R
- R to L
What causes a left to right cardiac shunt?
- High pressure in the left heart and lower pressure in the right heart
- Could also be seen in aorta to pulmonary trunk due to PDA
What does a person with a left to right shunt present with clinically? Why?
- Asymptomatically with no cyanosis
- This is due to the higher pressure side being oxygenated
What are the different defects that cause a left to right shunt?
- ASD
- VSD
- PDA
What causes a right to left cardiac shunt?
- When blood bypasses the pulmonary circulation
What does a person with a right to left shunt present with clinically?
- Symptomatic with cyanosis
What are the different defects that cause a right to left shunt?
- Tetralogy of Fallot
- Transposition of the great vessels
- Tricuspid atresia
What can arise if there is a shunt reversal in a normally left to right shunt?
- Paradoxical embolus
How do an ASD and VSD specifically cause a left to right shunt?
- They increase the right ventricular and pulmonary outflow volumes
How does a PDA specifically cause a left to right shunt?
- Increases pulmonary blood flow, pulmonary pressure, and HTN
What are the types of ASD?
- Secundum ASD
- Primum anomaly
- Sinus venosa defect
What is a secundum ASD?
- 90% of all ASD cases
- Located in the center of the septum
What is a primum anomaly?
- 5% of all ASD cases
- Located adjacent to the AV valves
- Associated with AV valve abnormalities and/or VSD
What is a sinus venosa defect?
- 5% of all ASD cases
- Located near the entrance of the SVC
- Associated with anomalous pulmonary venous return
What is the clinical features of ASD’s?
- Usually asymptomatic until adulthood when it causes an ejection systolic murmur
- Mortality is low
What is the most common form of congenital heart disease?
- VSD (90% are membranous)
What are the clinical aspects of a VSD?
- Cause a holosystolic murmur
- Effects depend on size and presence of other heart defects
What can large VSD shunting lead to?
- Right ventricular hypertrophy, heart dysfunction
- Pulmonary hypertension
- Unclosed VSD could lead to a shunt reversal causing cyanosis and death
What is the shunt reversal process called?
- Eisenmenger syndrome
What is the pathogenesis of Eisenmenger syndrome?
- A left to right shunt has an increase in pulmonary blood flow
- Irreversible endothelial dysfunction and pulmonary vascular remodeling occurs
- The increase in vascular resistance causes an inverted shunt
What are some problems with patients that have a patent foramen ovale?
- 20% do not close and the flap can open if the right sided pressure is increased
- Even a slight increase in pressure can cause a R-L shunt
What are some examples that increase the right sided pressure in a patent foramen ovale?
- Valsalva, bowel movements, coughing/sneezing
What could happen in a patent foramen ovale?
- Paradoxical embolus
What are some reasons that a patent ductus arteriosus will fail to close?
- If an infant is hypoxic or have defects with increased pulmonary vascular pressure
What kind of murmur is produced with a PDA?
- Machinery like murmur
How does a PDA present in a patient?
- Usually asymptomatic at birth
- Have a left to right shunt and usually no cyanosis
What can help close an isolated PDA?
- Indomethacin
What can be given to keep a PDA patent? Why would we do this?
- PGE is given to preserve PDA
- Can be lifesaving in certain congenital malformation
What are the four principal features of Tetralogy of Fallot?
- VSD
- Right ventricular hypertrophy
- Pulmonary valve stenosis
- Overriding aorta
What are “tet” spells?
- Cyanosis
- Syncope during emotional distress, excitement, or increased activity
What should you look for in someone with Tetralogy of Fallot?
- Infants will be cyanotic at birth
- Tet spells
- Compensatory squatting in children to relieve symptoms
- Boot shaped heart on CXR
What occurs in the transposition of the great arteries?
- Aorta and pulmonary artery are switched
What is expected at birth in an infant with tetralogy of fallot?
- Cyanosis
- Incompatible with life unless there is a shunt in place (VSD, PDA, PFO)
What is tricuspid atresia?
- Complete occlusion of the tricuspid valve
How is oxygenation maintained in tricuspid atresia?
- By a shunt like ASD/PFO AND a VSD
What is expected at birth in an infant with tricuspid atresia?
- Severe, immediate cyanosis with a high mortality rate
What is coarctation of the aorta?
- Focal narrowing of the aorta
Who is most likely to present with coarctation of the aorta?
- Most common in male
- But also seen sometimes in Turner’s syndrome
What other pathologies are seen with coarctation of the aorta?
- Bicuspid atresia
- Berry aneurysm
What is seen in the infantile form of coarctation of the aorta?
- PDA is seen
- Infant will have cyanosis of their lower half
- Absent femoral pulses
- May have heart failure and shock
What is seen in the adult form of coarctation of the aorta?
- PDA is absent
- Usually asymptomatic but there will be HTN in UE and hypotension in LE
- LE will be cold and femoral pulse delay
- May see concentric LV hypertrophy and dysfunction
Where does coarctation of the aorta occur in infants? Adults?
- Infants: before or on PDA
- Adults: after ligamentum arteriosum
What does mild aortic stenosis cause?
- LV hypertrophy
Where is aortic stenosis seen?
- In hypoplastic left heart syndrome
- ASD with PDA provides blood
What is seen in pulmonary stenosis?
- Mild, isolated stenosis or part of tetralogy of fallot/transposition of great arteries
What is the leading cause of death in US?
- Ischemic heart disease
What increases the risk of coronary artery disease?
- Age
- Male gender
- Postmenopausal women
What are some causes of ischemic heart disease?
- Atherosclerosis
- Coronary artery emboli
- Myocardial vessel inflammation
- Vessel spasm
What are the clinical features of ischemic heart disease?
- Prolonged substernal chest pain (crushing, stabbing, squeezing)
- Radiates to neck, shoulder, or jaw
- Rapid, weak pulse
- Profuse sweating
- Nausea and vomiting
- Dyspnea and discomfort
What is the earliest a biomarker for ischemic heart disease?
- CKMB is the earliest at 3 hours
When does the CKMB biomarker normalize?
- 48-72 hours
when do the cTnI and cTnT biomarkers normalize?
- > 5 days
What is the best biomarker used to look at MI?
- Troponin I (most sensitive and specific)
If the LAD gets occluded, what section of the heart is affected?
- Apex
- LV anterior wall
- Anterior 2/3 of septum
If the left circumflex gets occluded, what section of the heart is affected?
- LV lateral wall
If the right coronary artery gets occluded, what section of the heart is affected?
- RV free wall
- LV posterior wall
- Posterior 1/3 of septum
What is the pathway of necrosis in myocytes after an MI?
- Necrosis occurs from inside to outside (it starts furthest away from the vessels)
What happens on day 1 after an MI?
- Coagulative necrosis occurs presenting with wavy fibers on histo, some neutrophils present
- Life threatening arrhythmias present
- Cardiogenic shock occurs due to contractile dysfunction
What happens on day 3 after an MI?
- A yellow infarct necrosis, hyperemic border is present on gross exam
- Marked acute neutrophilic inflammatory infiltrate on histo
What happens on days 3-7 after an MI?
- Macrophages become more prominent to get rid of necrosed tissue
- Mitral regurgitation occurs due to ischemic papillary muscles
- Papillary muscle, ventricular septal wall, and left ventricular wall could all rupture
- Acute pericarditis
What happens 1-2 weeks after an MI?
- Some granulation tissue has formed with some deposition of collagen
- Chronic pericarditis occurs due to autoimmune reaction towards myocardial proteins released into blood (Dressler syndrome)
- Life threatening arrhythmias occur due to remodeling of myocardium
What happens 2 months after an MI?
- Scarring with dense fibrosis is seen on histo
What are some risk factors for a myocardial rupture?
- Increased age
- First MI
- Absence of LV hypertrophy
What does a myocardial rupture cause?
- Acute pericardial tamponade
Who is a myocardial rupture most likely seen in?
- Elderly due to decreased muscle mass
What is Dressler Syndrome?
- An autoimmune reaction to myocardial proteins in the blood
What does dressler syndrome present with?
- Fever
- Pleuritic pain
- Pericardial effusion
What is a ventricular aneurysm?
- Occurs after a large transmural infarct with expansion
- There is a thin walled scar which causes the aneurysm
What is angina pectoris?
- A transient, often recurrent chest pain
What induces the chest pain in angina pectoris?
- Myocardial ischemia but not enough to induce an MI
What are the three variants of angina pectoris?
- Stable angina
- Prinzmetal angina
- Unstable angina
What is stable angina?
- A stenotic occlusion of the coronary artery
What is the presentation of stable angina?
- Substernal pressure
- Squeezing
- Burning
What relieves the symptoms of stable angina?
- Rest
- Vasodilators
What induces stable angina?
- Physical activity
- Stress
What is prinzmetal angina?
- Episodic coronary artery spasm
What relieves the symptoms of prinzmetal angina?
- Vasodilators
Is prinzmetal angina related to physical activity, HR, or BP?
No
What is unstable angina?
- Caused by rupture of athersclerotic plaques with partial thrombus
What is the presentation of someone with unstable angina?
- Present at rest
- Has a crescendo pattern of increasing duration or severity
What should be assumed if someone presents with sudden onset of dyspnea, SOB, crushing, stabbing, or squeezing chest pain that radiates to the jaw?
Transmural acute MI
