Cardiothoracic Surgery Flashcards
What are the indications for CABG? (5)
- more than 70% left main stem stenosis
- symptomatic patients with more than 70% proximal left anterior descending disease
- symptomatic patients with more than 70% disease in all three vessels
- concommittent valvular disease which requires replacement
- vessel disease in a diabetic
What can be used as a conduit in a CABG? (3)
- saphenous vein
- left internal mammary artery
- radial artery
What is the CABG procedure?
conduit is anastamosed to the coronary artery beyond the lesion and then to the ascending aorta
What conduit is the conduit of choice for a left anterior descending artery CABG?
left internal mammary artery/internal thoracic artery
What are the complications of CABG? (7)
- death - 0-1% in low risk patients
- stroke - 1-2% in low risk patients
- resternotomy for bleeding or tamponade - 5%
- chest infection
- atrial fibrilation
- wound infection
- renal failure
What are the characteristics of a mechanical valve?
- lifelong (more than 20 years)
- requires warfarin
- noisy - metallic click
What are the characteristics of a bioprosthetic valve?
- shorter life (10-15 years)
- no need for warfarin
- silent
What is involved in a standard tripple bypass?
- Left internal mammary artery to the left anterior descending artery
- portion of harvested great saphenous vein from aorta to the circumflex artery
- portion of harvested great saphenous vein to distal right coronary artery
What is the aetiology of aortic stenosis?
- calcific degeneration
- bicuspid valve
- rheumatic disease
What is the triad of symptoms seen in aortic stenosis?
- syncope
- angina
- dyspnoea
what are the signs seen in aortic stenosis?
- ejection systolic murmur, loudest in the aortic region and radiatin to the carotids
- heaving apex beat
What would an ECG show in aortic stenosis?
may show left ventricular hypertrophy
What investigations should be done for aortic stenosis?
- ECG
- TTE
What are the indications for surgery in aortic stenosis?
- mean gradient actoss valve greater than 40mmHg
- symptomatic aortic stenosis
What are the surgical options for aortic stenosis?
- open surgical aortic valve replacement SAVR via thoracotomy
- transcatheter aortic valve implantation TAVI
What is the most common valvular lesion?
aortic stenosis
What is the second most common valvular lesion?
mitral regurgitation
What is the aetiology of mitral regurgitation?
- mitral valve prolapse due to ischaemia
- rheumatic disease
- infective endocarditis
- connective tissue disorders
What is characteristic of mitral regurgitation?
holosystolic murmur loudest at apex +/- third heart sound that can radiate to the axilla
What is the clinical presentation of acute mitral regurgitation?
signs of CCF
What is the clinical presentation of chronic mitral regurgitation?
- exertional dyspnoea
- orthopnoea
- displaced apex beat
- atrial fibrilation in 80%
What investigations need to be done in mitral regurgitation?
- TTE
- TOE
What are the indications for surgery in mitral regurgitation?
- acute mitral regurgitation
- severe chronic mitral regurgitation
What ate the surgical options for mitral regurgitation?
- open valve replacement
- endovascular mitraclip
What is the prevalence of mitral stenosis?
less than 1%
What is the clinical presentation of mitral stenosis?
- rumbling mid diastolic murmur at apex
- signs of right heart failure - due to increased pulmonary vascular resistance
- atrial fibrilation
4, left parasternal heave - tapping apex beat
What investigations should be done in mitral stenosis?
- CXR showing splaying of carina
- TTE/TOE
What are the surgical options for mitral stenosis?
- percutaneous valvotomy
- open mitral valve replacement
What is the prevalence of aortic regurgitation?
less than 1%
What is the aetiology of aortic regurgitation?
- rheumatic disease
- marfan’s syndrome
- large vessel vasculitis
- infective endocarditis
- aortic dissection
What is the clincal presentation of aortic regurgitation?
early diastolic murmur
What is the presentation of acute aortic regurgitation?
signs of left ventricular failure
What are the common causes of acute aortic regurgitation?
endocarditis
aortic dissection
What is the presentation of chronic aortic regurgitation?
often asymptomatic
What does aortic regurgitation show on a CXR?
cardiomegaly
What investigations should be done for aortic regurgitation?
CXR
TTE
What are the indications for surgery in aortic regurgitation?
- acute AR
- chronic AR
- left ventricular dilation more than 5.5 cm
What is the definition of a pneumothorax?
presence of air in the pleural space with varying degrees of secondary lung collapse
who does primary spontaneous pneumothorax occur in most commonly?
tall young men
What side is a primary spontaneous pneumothorax most common in?
right sided
What is a primary spontaneous pneumothorax caused by?
caused by rupture of small pleural blebs
Where is a primary spontaneous pneumothorax usually found?
usually found in the apex
what are the clinical features of primary spontaneous pneumothorax?
- dyspnoea
- chest pain
- tachypnoea
- hyperresonant hemithorax
- absent breath sounds
what investigations should be done in the case of a primary spontaneous pneumothorax?
CXR
CT thorax
What are the complications of a primary spontaneous pneumothorax?
tension pneumothorax
pneumomediastinum
haemopneumothorax
recurrent pneumothorax
How is a spontaneous primary pneumothorax managed conservatively?
if small and asymptomatic repeart CXR and supplemental oxygen
How is a spontaneous primary pneumothorax managed conservatively?
if small and asymptomatic repeart CXR and supplemental oxygen
When is needle aspiration done in a primary spontaneous pneumothorax?
if more than 2cm rim of air seen
When and where is a chest tube inserted in the case of a spontaneous primary pneumothorax?
when aspiration fails
where: fourth to fifth intercostal space in the mid axillary line
What is the aetiology of secondary spontaneous pneumothorax?
chronic airway or alveolar disease
systemic connective tissue disorders
malignant lung and chest disease
What chronic airway or alveolar diseases can cause a secondary spontaneous pneuomothorax?
severe asthma, cystif fibrosis, emphysema
What systemic connective tissue disorders can cause secondary spontaneous pneumothorax?
rheumatoid arthritis, ankylosing spondylitis, scleroderma, marfans syndrome, ehlers danlos syndrome
What malignant disease can cause secondary spontaneous pneumothorax?
bronchial cancer, sarcoma
What are the borders of the triangle of safety?
lateral border of pectoralis major, anterior border of latissmus dosi
How is a chest tube inseted?
inserted in the fifth intercostal space anterior to the mid axillary line, just above the rib to avoid the neurovascular bundle
How to confirm chest tube has been placed correctly?
- bubbling of air in the underwater chamber
- oscillation of fluid in the tube with the patients breathing
- post insertion CXR
