Cardiovascular system Flashcards
What forms the right border of the heart, the left border of the heart and the inferior border?
- Right border- Right atrium
- Left border- Left ventricle
- Inferior border- Mostly right ventricle
Calculate the cardio-thoracic ratio of X-ray below and express it as a percentage. State if the ratio is in the normal range.
- Cardio thoracic ratio is about 40%
- Should occupy less that 50% or less of the maximum width of the thoarx measured between inner marhins of the ribs
Express the cardiothoracic ratio of X-ray 2 as a percentage and comment on the degree of enlargement.
The cardiothoaracic ratio is 70% but should be less than 50%
Give 2 reasons why the heart shadow may become enlarged.
- Dilated left ventricle
- Ventricular hypertrophy
- Pericardial effusion which has build up over some considerable time
Where on the precordium would you feel for the apex beat if the heart is normal?
- The apex beat should normally be felt in the 5th intercostal space at the mid-clavicular line
Name the artery indicated by letter A and state which artery this is a branch of
- Left anterior descending artery
- Branch of the left coronary artery
What regions of the heart are supplied by the artery labelled A?
- Anterior aspect of the heart including the left venticle and interventricular septum
What would happen in LAD becomes occluded?
- The patient would suffer myocardial infarction
Describe the sequence of changes in an arterial wall which lead to arterial occlusion.
- An atheromatous placque forms
- The placque ruptures
- This allows a thrombus to form
- The thrombus either occludes artery or a portion of it breaks loose to travel as an embolus to a smaller artery which it occludes
What typical symptoms are experienced by a patient with a myocardial infarction?
- Central crushing check pain which may radiate to the arm, neck or jaw
Name the artery labelled B and explain why a blockage in this artery is more likely to cause a rhythm distubance
- Right coronary artery
- Supplies the SA Node in most individuals and the AV Node in most individuals
On the diagram label the arround to indicate the point where the
a) AV valves close
b) AV valves open
c) aortic valve closes
d) aortic valve opens
In the shaded band labelled A what happens to the left venticular volume and pressure?
- Left venticular volume does not change
- Left ventricular pressure increases
- Isovolumetric contraction
Mark on the diagram the positions where the aorta is at its narrowest and widest diameter?
Mark on the diagram the position of atrial systole
Labelled the structures labelled C, D and E
- C= flaps of the mitral valve
- D= Chordae tendinae
- E= wall of the ventricle
What is the function of Chordae Tendinae?
- Pulls the valve flaps taught during systole to prevent prolapse of the valve
If the mitral valve is imcompetent (fails to close properly) state what will happen to the glow of blood and what would you hear on auscultation of the heart
- Blood will flow back (regurgitation) into the left atrium during systole
- Systolic murmur
If the Mitral valve is stenosed (difficult to open) state what would happen to the flow of blood and what would you hear on auscultation of the heart
- The flow of blood across the valve during diastole will be turbulant
- Mid-diastolic murmur
In a patient with long standing mitral valve stenosis what would happen to the left atrium
- Left atrium would become dilated
- This is because of the increased pressure and volume because it is harder for blood to flow through the stenosed valve
Describe the struction of the pericardial sac?
- Outer fibrous layer
- Double serous layer consisting of an inner visceral layer and an outer parietal layer
In some patients if a large pericardial effusion develops rapidly it can cause cardiac tamponade. What is meant by the term cardiac tamponade?
- Cardiac tamponade is compression of the heart leading to a fall in arterial blood pressure (haemodynamic compromise)
In a patient with cardiac tamponade why would cardiac output fall?
- There is rapid fluid build up and outer fibrous layer cannot expand
- This puts external pressure on the heart preventing it from filling properly in diastole
What would you do to improve the clinical stuitation in Cardiac tamponade?
- Insert a needles to remove fluid from the pericardial sac
- Pericardiocentesis
There are 4 defects in the picture below, match the flowing defects to the letter in the diagram:
Ventiruclar septal defect
Right ventrciular outflow obstruction- Pulmonary stenosis
Overriding aorta
Right ventricular hypertrophy
What is this congenital heart defect called?
Tetralogy of fallot
Would a baby born with this condition by cyanosed? Explain your answer.
Yes because there is mixing of deoxygenated blood with oxygenated blood leaving the heart
If a baby is born with venticular septal defect alone would the baby be cyanosed?
No
What long term impact would a large venticular septal defect have on the pulmonary circulation if left untreated?
- Extra blood flow through the pulmonary circulation could damage the pulmonary vasculature causing vasculature causing vascular re-modelling (or hypertrophy of smooth muscle cells in the tunica media) and increased pulmonary resistance
