Week 8: Cardiovascular System Pathologies

Question 1

Congenital Heart Disease

Answer 1

• general term used to describe many congenital heart defects
• most common are left-to-right shunts (3 of them: atrial or ventricular septal defect, & patent ductus arteriosus) permit mixing of blood in systemic and pulmonary circulations
• blood shunts from high-pressure systemic circulation to lower-pressure pulmonary circulation overloading the lungs with blood
• increased load on the heart may cause enlargement (cardiomegaly) depending on location and size of shunt
• need surgical intervention unless very small
• ex: tetralogy of fallot, coarctation of aorta (both need surgical intervention)

Question 2

Atrial Septal Defect/ 
Patent Foramen Ovale

Answer 2

• free communication between both atria as a result of the lack of closure of the foramen ovale after birth
• most common congenital cardiac defect
• shunt overloads right ventricle
  -radiographic appearance: enlargement of right ventricle, atrium and pulmonary outflow tract

Question 3

Patent Ductus Arteriosus

Answer 3

• vessel shunts blood from the pulmonary artery into the systemic circulation during intrauterine life - does not close after birth
• shunt causes an excess volume of blood returned to the left atrium & left ventricle
• radiographic appearance: enlarged left atrium, left ventricle & pulmonary arteries, prominent aortic knob

Question 4

Tetralogy of Fallot (TOF)

Answer 4

• four abnormalities, cause right to left shunt which causes unoxygenated venous blood to enter the left ventricle and then to systemic circulation
  1. Ventricular septal defect
  2. Pulmonary stenosis (narrowing)
  3. Misplaced aorta (overriding of the aortic orifice above the ventricular defect)
  4. Right ventricular hypertrophy (thickened wall)
• symptoms: cyanosis at birth, clubbing of fingers and toes, congestive heart failure (large VSD), only 10% of untreated patients live past 20 years
• radiographic appearance: heart ascribed as looking like a book (coeur en sabot)

Question 5

Coarctation of the Aorta

Answer 5

• constriction of aorta usually beyond branching of blood vessels to head and arms
• decreased blood flow to abdomen and legs leading to development of collateral circulation (enlargement of small vessels)
• normal arm BP, low BP in legs
• most common cause for hypertension in children

Question 6

Coarctation of the Aorta Radiographic Appearance

Answer 6

• rib notching due to pulsation of intercostal collateral vessels
• 2 bulges in aortic knob = figure 3 sign
• narrowing of vessel on angiography
• CT chest sagittal arterial phase demonstrates length and location

Question 7

Cardiomegaly

Answer 7

• can be congenital or acquired
• an increase in the size of the heart
• many pathologies can cause it, such as hypertension, and especially with CAD (coronary artery disease)

Question 8

Coronary Artery Disease (CAD)

Answer 8

• Narrowing of the coronary arteries
• Causes oxygen deprivation of the myocardium & potentially ischemic heart disease, so heart cannot work
• Narrowing attributable to atherosclerosis
• Tissue beyond at risk
• Collateral circulation may take over
• If tissue dies then heart cannot pump properly, causes heart attack (myocardial infarction)
  Angioplasty for treatment

Question 9

Angina Pectoralis

Answer 9

• also called angina or stable angina
• often a symptom of CAD
  Recurring severe chest pain
• may radiate to the neck, jaw, and left arm
• often associated with the sensation of chest tightness or suffocation
• often confused with indigestion
• caused by temporary oxygen insufficiency to the myocardium
• often occur after increased need for myocardial oxygen (exercise, stress)

Question 10

Myocardial Infarction

Answer 10

• heart attack
• usually from atherosclerosis or coronary arteries
• occlusion of a coronary artery from CAD deprives an area of myocardium of its blood supply leading to death of muscle cells
• heart can’t pump

Question 11

Congestive Heart Failure (CHF)

Answer 11

• Heart unable to pump blood at sufficient rate and volume to provide an adequate supply to body tissues
• Due to heart abnormality, hypertension, obstruction
• May need to increase mAs if pulmonary edema present

Question 12

Hypertension

Answer 12

• High blood pressure
• The leading cause of strokes and CHF
• Can also cause kidney damage
• Blood pressure is a function of cardiac output (amount of blood pumped per minute by the heart) and peripheral resistance (condition of vessel walls)
• Usually slow increase and long term (benign or idiopathic)
• Prolonged can cause left ventricle to enlarge and fail (hypertensive heart disease)
• May be sudden and increase quickly (called malignant)

Question 13

Aneurysm

Answer 13

• Weakness in vessel walls caused by atherosclerosis, infection, trauma or defect creating a bulge, or distention of an artery
• Usually involves aorta, and abdominal aorta specifically
• May rupture and cause immediate death depending on location
• Saccular aneurysm = one side of vessel involved
• Fusiform aneurysm = bulging throughout entire vessel circumference
• Multiple small aneurysms = generalized arterial inflammation (arteritis)

Question 13

Berry Aneurysm

Answer 13

• common in circle of Willis
• surgically treated with clip or coil

Question 14

Traumatic Rupture of the Aorta

Answer 14

• Occurs from closed chest trauma such as rapid deceleration, blast, or compression
• Also called aortic transection
• Near-complete tear through all the layers of the aorta
• Needs immediate treatment

Question 15

Aortic Dissection

Answer 15

• Potentially life-threatening condition, needs immediate attention
• Tear in the wall of the aorta (intima = inner layer) causes blood to flow between the layers of the wall of the aorta forcing layers apart
• Makes a true and false lumen
• False lumen may form aneurysm due to blood’s pressure
• From arterial hypertension, trauma, congenital defect

Question 15

Arteriosclerosis

Answer 15

• Occurs when the arterial walls thicken, harden and lose elasticity
• Often refers to calcification of small arteries
• May be due to fat, cholesterol, calcium deposits in arteries
• May be called hardening of the arteries

Question 15

Atherosclerosis

Answer 15

• Atherosclerosis is a specific type or further development of arteriosclerosis (terms often used interchangeably)
• Fat, cholesterol, or other deposits (like calcium) develop in the intima – called plaques
• Causes narrowing/ occlusion/ luminal stenosis of large and medium sized arteries
• Cholesterol (lipid or blood lipid) test is used to check levels of cholesterol in the blood and subsequent risk of plaque build up in vessels that can result in heart disease or stroke
• Plaque formation in cerebral arteries can lead to occlusion and CVA (stroke)
• Plaque formation in coronary arteries (CAD) can lead to occlusion and myocardial infarct (heart attack)

Question 15

Peripheral Vascular Disease (PVD)

Answer 15

-Peripheral arteriosclerotic disease, so hardening/ narrowing/ occlusion of vessels of legs and less often arms
- Radiographic appearance: diffuse vascular narrowing, irregularity of the lumen or filling defects, seen on an arteriogram (CT MRI or US)

Question 15

Thrombosis

Answer 15

• Thrombus = mass of coagulated blood or clot usually adhering to the vessel wall
• Precipitating factors include trauma, bacterial infection, arteriosclerosis, prolonged bed rest, airplane travel, or thickened blood (polycythemia = increased RBC)
• Usually vein not artery (veins lower pressure)
• Thrombus could be reabsorbed, grow to occlude vessel, or break off and become embolus

Question 15

Deep Venous Thrombosis (DVT)

Answer 15

• Thrombus development in deep veins
• Usually lower extremities
• Due to trauma, bacterial infection, prolonged bed rest, air travel, oral contraception use
• Leg are may be red, hot, swollen, painful
• Blood clot may dislodge to the lungs (pulmonary emboli) which can be fatal
• Dislodging can come from sudden movement

Question 16

Embolus

Answer 16

• May be thrombus or plaque that has broken off/ come loose = most common sources
• Can occur due to sudden thrombus movement of area
• A fat embolus is a possible complication of bone trauma, an air bubble may be introduced into vasculature and act as embolus
• Emboli circulate through the bloodstream and can become lodged in a vessel resulting in occlusion
• Leg vein thrombus or fat emboli from leg trauma will likely lodge in pulmonary artery = pulmonary embolism
• Cardiac, mitral valve and arterial thrombi may cause brain embolism

Question 17

Aortic Stenosis

Answer 17

• Obstruction of flow of blood exiting the heart (from the left ventricle)
• Increases workload of left ventricle
• May be caused by rheumatic heart disease, a congenital valvular deformity (especially bicuspid valve) or degenerative process of aging (idiopathic)

Question 17

Mitral Stenosis

Answer 17

• Stenosis (narrowing) of mitral valve(bicuspid/ left AV valve) (separates left atrium and left ventricle)
• Complication of rheumatic heart disease
• Results from diffuse thickening of valve by fibrous tissue and/or calcific deposits

Question 18

Pericardial Effusion

Answer 18

- Accumulation of fluids within pericardial space surrounding the heart (within double layered pericardial sac) - From bacteria, viruses, or neoplastic involvement or idiopathic - If slow development, pericardium can expand and heart can continue to function as normal - If fast, called cardiac tamponade, heart compressed by pressure from fluid, function and cardiac output reduced

Question 19

Arteriovenous Fistula/ 
Arteriovenous Malformation

Answer 19

- AVF = abnormal connection between artery and vein - Congenital or acquired (injury, surgery for dialysis) - Can occur anywhere in body - AVM = usually refers to brain - Can cause blood clots or bleeds (if rupture) - Tissues beyond the fistula may not receive adequate oxygenation (capillaries missed during circulation) - Angiography, MRI or CT - radiographic appearance: filling defect, unusual vasculature

Question 20

Arrhythmias

Answer 20

- Abnormal/ irregular heartbeat – too fast (tachycardia), too slow (bradycardia), irregular - From many causes including coronary artery disease and heart attack or scarring from previous one - From problem with electrical system of the heart muscle - Depending on cause and severity may remain untreated, treated with medication or electronic pacemaker

Question 21

Dextrocardia

Answer 21

- Heart is located in the right side of the chest and points to the right - Other organs may also be reversed - Can be asymptomatic/ no problems if by itself; often occurs with other conditions that cause problems - radiographic appearance: heart on right side of body