Cardiovascular Vivas Flashcards
What is used for biological (bioprosthetic) valve replacement?
Bovine or porcine
What is the most common mechanical valve used?
Bileaflet valve
(ball and cage now rarely used)
What is the major disadvantage of biological valves?
Structural deterioration + calcification
May require future replacement, posing additional risks
What is the major advantage of biological valves?
Lower risk thrombogenesis
Long term anticoagulation not usually needed
Warfarin maybe given for first 3 months depending on patient factors
Describe the use of aspirin in biological valves
Low dose aspirin given longterm
In which patient group are biological valves preferred?
> 65s for aortic valves
70s for mitral valves
What is the main advantage of mechanical valves?
Greater longevity +
low failure rate
What is the major disadvantage of mechanical valves?
Increased risk of thrombosis meaning long term anticoagulation is needed
What is the preferred form of anticoagulation for patients with mechanical heart valves?
Warfarin
What is the target INR for aortic and mitral mechanical valves?
Aortic: 3.0
Mitral: 3.5
Describe the use of aspirin in mechanical valves
Only given if additional indication e.g. IHD
What are the guideline regarding prophylaxis of endocarditis in patients with valve replacements?
No abx recommended for common procedures
3 features of typical Anginal chest pain
- Constricting discomfort in front of chest, neck, shoulders, jaw or arms
- Precipitated by physical exertion
- Relieved by rest or GTN in ~5 mins
4 Midline sternotomy causes
Open aortic/ mitral valve surgery
Coronary artery bypass grafting (CABG)
Cardiac transplant
Correction of congenital cardiac defects
4 symptoms of aortic stenosis
Fatigue
Dyspnoea
Exertional syncope
Exertional angina
Mx of AS
Asymptomatic: monitor
Symptomatic: valve replacement
Asymptomatic but valvular gradient > 40 mmHg + features such as LV systolic dysfunction, consider surgery
First line Mx of symptomatic AS
Open AV replacement
High operative risk: Transcatheteric AV implantation (TAVI= repair without need for removal)
3 aetiologies of mitral regurgitation
Ischaemic: papillary muscle rupture post MI
Non-ischaemic: IE, RHD
Iatrogenic: rare, due to trauma of leaflets/ chords e.g. in TAVI
Acute MR symptoms
Sudden + marked increase in congestive HF Sx, with weakness, fatigue, dyspnoea, respiratory failure + shock.
a/w peripheral vasoconstriction, pallor, + diaphoresis.
2 Chronic MR symptoms
Exertional dyspnoea
Fatigue
4 causes of chronic AR due to valve disease
Rheumatic fever: most common cause in developing world
Calcific valve disease
CTDs e.g. RhA/ SLE
Bicuspid aortic valve (affects valves + aortic root)
5 causes of chronic AR due to aortic root disease
Bicuspid aortic valve (affects both valves + aortic root)
Spondylarthropathies (e.g. Ank spond)
HTN
Syphilis
Marfan’s, Ehler-Danlos syndrome
2 causes of acute AR
Infective endocarditis
Aortic dissection
Symptoms of AR
Asymptomatic
Exertional dyspnoea
Angina
HF Sx: Orthopnoea, PND, pulmonary oedema
Mx of AR
Medical Mx of any associated HF
Surgery:
Symptomatic patients with severe AR
Asymptomatic patients with severe AR + LV systolic dysfunction
Investigation of choice for aortic dissection
CT angiography of the chest, abdomen + pelvis
False lumen
Suitable for stable patients + for planning surgery
Investigation for aortic dissection in unstable patients
Transoesophageal echo
What causes rheumatic fever?
Immunological reaction to a recent (2-4w ago) Streptococcus pyogenes infection.
