Surgery for IHD and VHD Flashcards
What are some common causes for cardiac ischaemia?
Atherosclerosis
Embolism
Coronary thrombosis
Aortic dissection
Arteritides
Congenital
What are some manifestations of ischaemic heart disease?
Angina, MI, arrhythmias, chronic heart failure and sudden death
What are the dangerous patterns of coronary artery disease?
Left main stem stenosis
3 vessel coronary artery disease
What are the indications for coronary artery bypass grafting?
Symptomatic - any cardiac pattern
Prognostic - LMSS, 3VDx
What is included in selection of patients for CABG?
Adequate lung function, mental function, hepatic function, ascending aorta is okay, distal coronary targets and LVEF>20%
What conduits for CABG?
Reversed saphenous vein
Internal mammary arteries
Radial arteries
Describe a sternotomy
Procedure to separate your sternum (breastbone). Cardiac surgeons frequently use it to access your heart and aortic arch during surgery
When is radial artery used in CABG?
If problem with varicose veins
What are some related problems to a sternotomy?
Wire infection, painful wires, sternal malunion and sternal dehiscence (muscle on wound breaks down)
What are some post-op problems in cardiac surgery?
Cardiac tamponade, death and stroke
What are the primary features of cardiac tamponade following cardiac surgery?
Raised CVP, raised heart rate and low BP
What are the secondary features of cardiac tamponade following cardiac surgery?
oliguria, increased oxygen requirements and metabolic acidosis
What is the treatment of cardiac tamponade?
Chest re-opening
What are the long term outcomes post CABG?
50% have no further cardiac problems 10 years later
Majority of problems are minor and fixed with meds
Only 5% may need repeat CABG
What are the surgeries for valvular heart disease?
Adult cardiac surgery - mainly aortic and mitral valves
Paediatric Cardiac surgery - all 4 heart valves operated on in equal frequency
What are some causes of valvular heart disease in adults?
Degenerative, congenital, infective, inflammatory, LV or RV dilatation, trauma, neoplastic and paraneoplastic
What are the most common problems requiring cardiac valve surgery?
Senile tricuspid AS
Bicuspid AS
Degenerative MR
Explain Rheumatic fever
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
What is rheumatic fever treated with?
Aspirin and bed rest
Explain chronic rheumatic heart disease
Gradually progressive MVDx and maybe AVDx
Is most common heart problem and major cause of death in pregnancy
What are common organisms that can give rise to endocarditis?
Strep viridans is most common - subacute bacterial endocarditis
Straph aureus is also common - acute bacterial endocarditis
Explain chances of cure and endocarditis
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
What are the indication for surgery in endocarditis?
Severe valvular regurgitation
Large vegetations
Persistent pyrexia
Progressive renal failure
How long are antibiotics given post-op after surgery for endocarditis?
Given by IV for 6 weeks
What are the typical presentations for aortic stenosis?
Heart failure, angina, syncopal episodes or as an asymptomatic incidental finding
Murmur usually easily heard
Loss of aortic S2 differentiates it from aortic stenosis
What is recommended for severe AS?
Aortic valve replacement (AVR)
Describe the murmur in mitral stenosis?
Usually difficult to hear
Easily heard if stenosis is severe
May need to exercise the patient to hear the murmur
When is surgery recommended in patients with mitral stenosis/
If MVA on echo is <1.5 cm2
Describe the murmur in mitral regurgitation
Murmur is usually easy to hear and if loud then usually severe
What is severe MR associated with?
LV and LA dilatation, onset of AF and pulmonary hypertension
What is Severe MR on echo characterised by?
Systolic blood flow reversal in the pulmonary veins
Describe cardiopulmonary bypass
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
What is the max. time limit for CPB machine?
12 hours
What are the two types of heart valve prosthetics?
Biological valve and mechanical valves (need warfarin)
