Rad Path Chapter 7 Pathologies

Function of the cardiovascular system

maintain an adequate blood supply of blood to all tissues in the body

Which chemical slows heart action?

acetylcholine

Which chemical increases heart rate?

epinephrine

Which valve separates the left atrium from the left ventricle?

mitral (bicuspid) valve

Which valve separates the right atrium from the right ventricle?

tricuspid valve

Which valves separate the ventricles from the great vessels leaving the heart?

semilunar valves

What lies between the right ventricle and pulmonary artery?

pulmonary valve

What separates the aorta from the left ventricle?

aortic valve

Blood flow through the heart

1-Superior & Inferior Vena Cava, 2-Rt Atrium, 3-Tricuspid Valve, 4- Rt Ventricle, 5-Pulmonary Valve, 6-Pulmonary Artery, 7- Lungs-pick up oxygen, 8-Pulmonary Veins, 9- Lt Atrium, 10- Mitral Valve (Bicuspid), 11-Lt Ventricle, 12- Aortic Valve, 13-Aorta, 14- Body

Systole

contraction phase

Diastole

relaxation phase

Systemic circulation

general circulation of the body

Pulmonary Circulation

Circulation of blood through the lungs

Left-to-right shunts

most common congenital cardiac lesions, permit mixing of blood in the systemic and pulmonary circulations

3 types of left to right shunts

1. atrial septal defect (most common)

2. ventricular septal defect

3. patent ductus arteriosus- remnant of fetal circulation, appears as enlargement of left atrium, left ventricle, and central pulmonary arteries

Eisenmenger syndrome

Pulmonary hypertension caused by complications from left to right shunts

Tetralogy of Fallot

most common cause of cyanotic congenital heart disease, produces right to left shunting

best demonstrated by echocardiography and MRI

1. high ventricular septal defect

2. pulmonary stenosis

3. overriding of the aortic orifice above the ventricular defect

4. right ventricular hypertrophy

couer en sabot

Radiographic appearance of tetralogy of fallot, heart resembles curved-toe portion of a wooden shoe

Coarctation of the aorta

Narrowing of the aorta

Most commonly occurs just beyond the branching of the blood vessels to the head and arms

Classic sign- normal BP in arms, very low in the legs

Most frequent cause of hypertension in children

Sign on chest x-ray- rib notching

Figure 3, figure E signs

Coronary Artery Disease

Narrowing of the lumen of one or more of the coronary arteries

Most commonly caused by atherosclerosis (deposition of fatty material on the inner arterial wall)

Results in oxygen deprivation of myocardium and ischemic heart disease

Commonly identified by coronary arteriography and CT coronary angiography

Myocardial infarction

When occlusion of a coronary artery deprives an area of myocardium of its blood supply and leads to the death of muscle cells

Congestive Heart Failure

inability of the heart to pump its required amount of blood

Causes- intrinsic cardiac abnormality, hypertension, any obstructive process that abnormally increases the peripheral resistance to blood flow

Pulmonary Edema

abnormal accumulation of fluid in the extravascular pulmonary tissues

Most common cause- elevation of pulmonary venous pressure, most often attributable to left sided heart failure, but also pulmonary venous obstruction or lymphatic blockade

Other causes: uremia, narcotic overdose, exposure to noxious fumes, excessive oxygen, high altitudes, fat embolism, ARDS, various neurologic abnormalities

Hypertension

high blood pressure

Fibromuscular dysplasia

major cause of renovascular hypertension

occurs frequently in young females, often bilateral

Most common radiographic appearance- string-of-beads pattern

Hypertensive Heart Disease

long-standing high blood pressure causes narrowing of systemic vessels and increased resistance to blood flow

Left ventricle forced to assume increased workload, initially causing hypertrophy

Aneurysm

localized dilation of an artery that most commonly involves the aorta, especially its abdominal position, US modality of choice for identification

Saccular aneurysm

involves only one side of the arterial wall

Fusiform aneurysm

bulging of the entire circumference of the vessel wall

Traumatic Rupture of the Aorta

potentially fatal complication of closed-chest trauma, usually occurs just distal to left subclavian artery at ductus arteriosus, CTA modality of choice

Dissection of the Aorta

a potentially life-threatening condition in which disruption of the intima (the inner layer) permits blood to enter the wall of the aorta and separate its layers, divides aorta into true and false lumens

Atherosclerosis

thickening, hardening, and loss of elasticity in the arterial wall

Thrombus

intravascular clot

Embolism

part or all of a thrombus that becomes detached from the vessel wall and enters the bloodstream

Rheumatic Heart Disease

autoimmune disease resulting from a reaction of the patient's antibodies against antigens from a previous streptococcal infection, damages valves of the heart making them either stenotic or insufficient

Mitral Stenosis

almost always a complication of rheumatic disease, results from diffuse thickening of the valve by fibrous tissues, calcific deposits, or both, echocardiography modality of choice

blood flow is obstructed from leaving the left atrium and passing into the left ventricle during diastole

Mitral Insufficiency

most often caused by rheumatic heart disease

Other causes: rupture of the chordae tendineae, dysfunction of the papillary muscles

Regurgitation of blood into the left atrium during ventricular systole causes overfilling and dilation of this chamber

Aortic Stenosis

Causes: rheumatic heart disease, congenital valvular deformity, or degenerative process of aging

obstruction to left ventricular outflow in aortic stenosis increases the workload of the left ventricle

Aortic Insufficiency

Most common cause: rheumatic heart disease

Other causes: syphilis, infective endocarditis, dissecting aneurysm, Marfan syndrome

Reflux of blood from the aorta during diastole causes volume overload in the left ventricle and dilation of this chamber

Infective Endocarditis

development of nodules or vegetations on heart valves caused by deposits of bacteria or fungi, demonstrated on echocardiography

Pericardial effusion

accumulation of fluid in the pericardial cavity

May result from bacteria, viruses, or neoplastic involvement

Rapid accumulation interferes with cardiac function because of increase in pericardial pressure

Deep Vein Thrombosis (DVT)

primarily involves lower extremities

major source of potentially fatal pulmonary embolism

Precipitating factors: trauma, bacterial infection, prolonged bed rest, oral contraceptives

May be earliest symptom of unsuspected malignancy of pancreas, lung, or GI system

Varicose Veins

dilated, elongated, and tortuous vessels that most commonly involve the superficial veins of the leg just under the skin