Surgery for IHD and VHD

Question 1

What are some common causes for cardiac ischaemia?

Answer 1

Atherosclerosis
Embolism
Coronary thrombosis
Aortic dissection
Arteritides
Congenital

Question 2

What are some manifestations of ischaemic heart disease?

Answer 2

Angina, MI, arrhythmias, chronic heart failure and sudden death

Question 3

What are the dangerous patterns of coronary artery disease?

Answer 3

Left main stem stenosis
3 vessel coronary artery disease

Question 4

What are the indications for coronary artery bypass grafting?

Answer 4

Symptomatic - any cardiac pattern
Prognostic - LMSS, 3VDx

Question 5

What is included in selection of patients for CABG?

Answer 5

Adequate lung function, mental function, hepatic function, ascending aorta is okay, distal coronary targets and LVEF>20%

Question 6

What conduits for CABG?

Answer 6

Reversed saphenous vein
Internal mammary arteries
Radial arteries

Question 7

Describe a sternotomy

Answer 7

Procedure to separate your sternum (breastbone). Cardiac surgeons frequently use it to access your heart and aortic arch during surgery

Question 8

When is radial artery used in CABG?

Answer 8

If problem with varicose veins

Question 9

What are some related problems to a sternotomy?

Answer 9

Wire infection, painful wires, sternal malunion and sternal dehiscence (muscle on wound breaks down)

Question 10

What are some post-op problems in cardiac surgery?

Answer 10

Cardiac tamponade, death and stroke

Question 11

What are the primary features of cardiac tamponade following cardiac surgery?

Answer 11

Raised CVP, raised heart rate and low BP

Question 12

What are the secondary features of cardiac tamponade following cardiac surgery?

Answer 12

oliguria, increased oxygen requirements and metabolic acidosis

Question 13

What is the treatment of cardiac tamponade?

Answer 13

Chest re-opening

Question 14

What are the long term outcomes post CABG?

Answer 14

50% have no further cardiac problems 10 years later
Majority of problems are minor and fixed with meds
Only 5% may need repeat CABG

Question 15

What are the surgeries for valvular heart disease?

Answer 15

Adult cardiac surgery - mainly aortic and mitral valves
Paediatric Cardiac surgery - all 4 heart valves operated on in equal frequency

Question 16

What are some causes of valvular heart disease in adults?

Answer 16

Degenerative, congenital, infective, inflammatory, LV or RV dilatation, trauma, neoplastic and paraneoplastic

Question 17

What are the most common problems requiring cardiac valve surgery?

Answer 17

Senile tricuspid AS
Bicuspid AS
Degenerative MR

Question 18

Explain Rheumatic fever

Answer 18

Is a relapsing illness and is related to streptococcal infections. ASO titre
Hallmark pathology is pericarditis
Skin and joint manifestations are usual
Sydenham’s chorea/ St Vitus’ dance

Question 19

What is rheumatic fever treated with?

Answer 19

Aspirin and bed rest

Question 20

Explain chronic rheumatic heart disease

Answer 20

Gradually progressive MVDx and maybe AVDx
Is most common heart problem and major cause of death in pregnancy

Question 21

What are common organisms that can give rise to endocarditis?

Answer 21

Strep viridans is most common - subacute bacterial endocarditis
Straph aureus is also common - acute bacterial endocarditis

Question 22

Explain chances of cure and endocarditis

Answer 22

NVE - 90% chance of cure with antibiotics alone
PVE - 50% chance of cure with antibiotics alone
Chances of cure much higher with strep viridans endocarditis than strep. aureus

Question 23

What are the indication for surgery in endocarditis?

Answer 23

Severe valvular regurgitation
Large vegetations
Persistent pyrexia
Progressive renal failure

Question 24

How long are antibiotics given post-op after surgery for endocarditis?

Answer 24

Given by IV for 6 weeks

Question 25

What are the typical presentations for aortic stenosis?

Answer 25

Heart failure, angina, syncopal episodes or as an asymptomatic incidental finding Murmur usually easily heard Loss of aortic S2 differentiates it from aortic stenosis

Question 26

What is recommended for severe AS?

Answer 26

Aortic valve replacement (AVR)

Question 27

Describe the murmur in mitral stenosis?

Answer 27

Usually difficult to hear Easily heard if stenosis is severe May need to exercise the patient to hear the murmur

Question 28

When is surgery recommended in patients with mitral stenosis/

Answer 28

If MVA on echo is <1.5 cm2

Question 29

Describe the murmur in mitral regurgitation

Answer 29

Murmur is usually easy to hear and if loud then usually severe

Question 30

What is severe MR associated with?

Answer 30

LV and LA dilatation, onset of AF and pulmonary hypertension

Question 31

What is Severe MR on echo characterised by?

Answer 31

Systolic blood flow reversal in the pulmonary veins

Question 32

Describe cardiopulmonary bypass

Answer 32

Blood is drained from RA and returned to the ascending aorta Heart and lung function taken over by CPB machine Systemic anticoagulation necessary - heparin Induced hypothermia and non-pulsatile flow during CPB

Question 33

What is the max. time limit for CPB machine?

Answer 33

12 hours

Question 34

What are the two types of heart valve prosthetics?

Answer 34

Biological valve and mechanical valves (need warfarin)