Cardiology Flashcards
What management is indicated on calcium score from CT-cardiac?
<100 = diet + lifestyle
101-400 = aspirin + statin
101 -400 + 75th centile = move to high risk category, aspirin + statin
> 400 = aspirin + statin aiming LDL < 2, consider functional assessment (eg stress echo or ETT)
How do you interpret calcium score on CT cardiac?
0 = very low risk of death, <1% in 10y
1-100 = low risk of death, <10% in10y
101-400 = intermediate risk, 10-20%
101-400& >75th centile = moderately high risk, 15-20%
>400 = high risk, >20%
When is calcium scoring of CT-cardiac not recommended?
Very low risk individuals <5% 10y risk
High risk individuals >20% 10y risk as does not change management
Symptomatic or known CAD
What is the value of combined calcium score in CT cardiac?
Can assess 10y cardiac risk of ASYMPTOMATIC individual 45-75 with intermediate risk profile (ie can move them to high or low risk)
What is the triple rule out principle on CTCA?
When used in acute chest pain syndrome CTCA can rule out:
-CAD
-aortic dissection
-pulmonary embolism
What causes false positives on CTCA?
Calcified plaques which cause blooming effect- does not always correlate with obstructive plaque on invasive coronary angiogram (gold standard). This causes LOW PPV
What are the sensitivity, specificity, PPV and NPV for CTCA?
High sensitivity = low false negatives
High specificity = low false positives
High NPV = rules out CAD
Low PPV = presence of CAD and degree of stenosis does not always correlate to obstructive plaque on invasive coronary angio
What are the indications for CTCA?
- Evaluation of chest pain syndrome with uniterpretable or equivocal stress test (ETT, stress echo)
- Evaluation of chest pain syndrome with intermediate pre test probability of CAD, uninterpretable ECG or unable to exercise
- Acute chest pain with intermediate pre test probability of CAD, no ECG changes and negative serial enzymes
How should stable ischaemic chest pain be investigated?
Non invasively:
-exercise or stress ECG
- exercise or dobutamine stress echo
- dipyridamole/adenosine nuclear perfusion
- cardiac CT or MRI (non stress)
What are the risks of invasive coronary angiography?
1 in 1000 risk:
-stroke
-MI
- contrast anaphylaxis
- major surgery at puncture site
- emergency angioplasty or surgery
- death
1 in 100 risk of
- arrhythmia
- surgical repair at puncture site
- minor contrast reaction
- AKI
1 in 20 risk of major bruising
1 in 10 lose pulse at radial puncture site
What is the gold standard for anatomical assessment in coronary artery disease?
Invasive coronary angiography
Compare and contrast cardiac CT and cardiac MRI
CTCA better at assessing coronary artery anatomy than MRI
MRI better at assessing myocardium - gadolinium uptake identifies scar
Compare and contrast cardiac MRI and SPECT imaging
cMRI better spatial resolution so better at detecting scar (esp subendocardial)
What is the gold standard for assessing coronary ischaemia?
Invasive coronary angiogram (specifically through measurement of FFR)
What is involved in stress echo?
- Pre stress echo: evaluates LVEF, diastology, valves, wall motion
- Stress applied (exercise or drug) and assess ECG, symptoms, haemodynamics, exercise capacity
- Post stress echo: wall motion, diastology, RVSP
How is myocardial ischaemia defined in stress echo?
Exercise induced ST changes or exercise induced RWMAs
How is myocardial ischaemia defined in ETT?
ST segment abnormality
Why is a stress echo more sensitive and specific than ETT?
Able to assess RWMAs - degree of wall thickening (should increase > 50%) which precedes ECG changes on ischaemic cascade
Less false negatives
Less False positives with stress echo for women
Rank ETT, CTCA, stress echo and nuclear medicine scans in terms of specificity and sensitivity for IHD
Least = ETT
Middle = stress echo, nuclear
Most = CTCA
What is LVH criteria?
S in V1orV2 + R in V6 >35
OR
S in V3 + R in aVL > 22
What complications associated with inferior STEMI?
- RVMI (dependent on pre load so avoid B-blocker)
- posterior wall MI
- lateral wall MI
- sinus and AV node dysfunction (Avoid B-blocker)
Major cause of mortality in iatrogenic hypotension
What is the most common valvular heart lesion?
Aortic stenosis
- most commonly degenerative
- 1% have bicuspid valve
Describe rheumatic AS
Fusion of commisures
How is severe AS defined?
AS jet velocity > 4 m/s
OR
Mean gradient >40 mmHg
OR AVA >1 cm2
What is a key feature of low flow severe AS?
Reduced stroke volume < 35 mL/m2
What is the only treatment that improves patient outcomes for severe AS?
Valve replacement
- low surgical risk = AVR
- intermediate risk = AVR or TAVR
- high risk = TAVR
What is the most common cause of Aortic Regurgitation?
Congenital abnormality such as bicuspid valve
Describe AR murmur
Early diastolic decrescendo murmur loudest left sternal edge
- increased on full expiration
- increased with handgrip or squat due to increased afterload
May also hear low pitched mid diastolic rumbling of austin flint murmur (where AR jet impinges AVML)
How is severe AR defined?
-Flail leaflet or wide coaptation defect
- large jets
- steep decceleration
- holodiastolic flow reversal in aorta
- dialted LV
What are the indications for AVR for AR?
Severe AS with symptoms or have impaired LVEF
Moderate or severe and if otherwise having cardiac surgery
What are causes of acute severe AR?
Aortic dissection or endocarditis or trauma
Short diastolic murmur
What are the two types of MR?
Primary: degenerative caused by leaflet prolapse, chordae rupture, endocarditis, RHD
Secondary: functional, normal valve in presence of LV dysfunction
Describe MR murmur
holosystolic murmur +/- diasotlic murmur
What LVEF indicates reduced LV function in severe MR?
LVEF < 60% indicates reduced contractility as MR reduces work of LV
How is primary severe MR managed?
symptoms or LV dysfunction and low surgical risk = MVR
high surgical risk = mitraClip (transcatheter edge to edge MV repair
How is secondary MR managed?
Managed medically as for HF +/- CRT as first line
If refractory:
- LVEF > 50% = MVR
- LVEF < 50% = MitraClip
Concurrent CABG = MVR
Surgical management 1st line does not reduce hospitalisations or death
What is acute rheumatic fever?
Systemic immune response to beta-haemolytic strep
Cardiac manifestation: pancarditis incl PR prolongation
MSK: polyarthritis, erythema marginatum, nodules
Syndenham chorea
Which valve is most commonly involved in RHD?
Mitral valve - more commonly stenosis
Describe appearance of rheumatic MS
Fusion of commisures = fish mouth
Thickened + restricted AVML = hockey stick
Which rheumatic valve disease should you give anticoagulation for A Fib regardless of CHADSVASc?
Mitral stenosis
In which rheumatic valve disease should you give a B-blocker for tachycardia with pulmonary oedema?
Mitral stenosis
Describe MS murmur
Low pitch diastolic rumble
(bell in left lateral with full expiration)
How is severe MR defined?
Valve area < 1.5 cm2
OR Mean gradient > 10 mmHg
Or PAP > 50 mmHg
What scoring tool helps to guide Mitral Stenosis treatment?
Wilkins score of mitral valve anatomy
When is intervention for rheumatic Mitral Stenosis indicated?
Balloon valvuloplasty for pliable valves with thrombus in severe or progressive MS
MVR for severe MS with severe symptoms and low surgical risk
What is the most common cause of tricuspid regurgitation?
80% are functional
Should isolated TR be managed surgically?
No - poor outcomes especially if RV dysfunction and pulmonary hypertension
What is Bernoulli equation and its use?
Change in pressure across orifice is proportional to square of velocity of fluid flowing through the orifice
DeltaP = 4Vsquared
Used to asses RVSP = 4x (TR velocity squared) + right atrial pressure
What is different about mixed valve disease?
Often does not progress to severe grade but associated with higher morbidity and mortality
Requires specialist team input to guide appropriate management
What are the Four acoustic windows of TTE?
- Parasternal - front of heart structures
- Apical - LV + RV
- Subcostal - pericardium + RV function + ASD
- Suprasternal - aortic arch, SVC, great vessels
How is LVEF calculated?
EF (%) = (LVEDV - LVESV)/LVEDV x 100
What is normal global longitudinal strain on TTE?
More than 20%
What information os gained from GLS on TTE?
- Can indicate RWMAs
- Early detection of cardiotoxicity in cancer therapies (earlier detection than LVEF)
How does HFpEF appear on ECHO?
- Abnormal relaxation = A wave > E wave in mitral doppler, slower decceleration in pulmonary vein
- Psuedo normal: E > A wave, shortened decceleration wave reflects overload
What is pre capillary pulmonary hypertension?
Where arterial tree is obstructed, PAP is greater than LA pressure
What is post capillary pulmonary hypertension?
Normal lung circulation but raised LA pressure causes high PAP
How is pulmonary hypertension measured on ECHO?
Doppler gradient across tricuspid valve + bernoulli equation to estimate RVSP
How is pulmonary hypertension defined?
PAP (equal to RVSP) > 20-25 mmHg
What is the significance of pre and post capillary hypertension with regard to management?
- post capillary hypertension should be managed with diuresis
- pre capillary should be treated with pulmonary vasodilator drugs
When is it safe to do DCCV for AFib?
- presentation with < 48 hours onset symptoms
- stabled on anticoagulation at least 4 weeks
- TOE rules out LAA thrombus
Same risk of stroke between these groups