Cholesterol, congenital, channelopathies Flashcards
High intensity statins & dose
- Atorvastatin 80mg / 40mg
- Rosuvastatin 40mg / 20mg
LDL target
<1.8 mmolL
Familial hypercholesterolaemia - gene mutations
- LDLR
- apoB
- PCSK9
Familial hypercholesterolaemia - most specific fx
- Tendon xanthoma (#1)
- corneal arcus
Kid <18 but >95th percentile
LDL >8.5
PSCK9 - names & effect when combined w/ Ezetimibe & statin (in FH)
- Alirocumab
- Evolucumab
- 85% reduction in LDL w/ combo
HCM - most common genetic mutations & what do they code
MYH7 (MYBPC3)
Encode myosin production & activity
Aortopathy - common genetic mutation
FBN-1 in Marfans
(also Ehlers Danlos (COL), Loeys Dietz (TGF & SMAD)
Long QT syndrome - types & channelopathies & mutations
AD - 80% have identifiable mutations (some crossover in 450-500msc range)
- Type 1 & 2: K channels (90%) - loss fxn (short QT is gain of fxn in gene)
- Type 3: Na channel (SCN5A) - gain of fxn (Brugada is gain of fxn in gene)
- LQT1 (50%): swimming
- LQT2 (40%): other exercise/emotion (eg fright)
- LQT3 (10%): asleep/at rest - bradycardic
* Auditory/post partum - catecholamines are triggers*
Long QT - Rx
- *B blockers**
- start straight away (most effective in QT1)
ICD: only if VT/VF, syncope or high risk
Screen FHx or high suspicion
CPVT: Catecholamine polymorphic VT - Fx, pathophys
Exercise induced (catecholamine) polymorphic VT (w/ normal QT)
Ryanodine receptor (mediates Ca release from SR)
AD inherited (RyR or CASQ2)
CPVT: Catecholamine polymorphic VT - Rx
- Beta blockers
- ICD if high risk
- 2nd line:
- Flecainide
- Verapamil
- (sympathetic denervation)
- No strenuous exercise unless ext defib available
Brugada - Fx
AD - SCN5a mutation (loss of fxn - Na channel)
V1-V3 downsloping ST w/ TWI
+ QRS can be wide like RBBB
Brugada - Rx
ICD (if sx/high risk, asx ECG - just monitor if low risk)
Avoid drugs
- Na channel blockers - Flecainide, Amiodarone, Propranolol
- CCB - Verapamil, Diltiazem
- ETOH/Cocaine
- Phenytoin, Lidocaine
Most common cardiac abnormality in Trisomy 21
Atrioventricular septal defect (AVSD)
VSD
Cardiac abN in Di George (22q) deletion
Tetralogy of Fallot
Which cardiac chamber develops vol OL in VSD
LV
(as each contraction, some flows through VSD, so needs to dilate/increase volume to maintain CO)
Which is the only shunt causing R) side volume OL
ASD
Associations w/ bicuspid AV
Aortic coarctation (interrupted aortic arch - claudication etc) 50% have bicuspid AV
Berry aneurysms (10%) - screen CTA
Most common cyanotic congenital heart defect
Tetralogy of Fallot
Anterior deviation on infundicular septum - leads to
- Unrestrictive VSD
- PS (usu RVOTO)
- Overriding aorta (moves to right)
- RVH
Rx: surgery (immediate if sx) - often have PR after
Most common ASD type
Ostium secundum (Fossa ovalis)
(Ostirum primum is partial AVSD - down syndrome etc)
Most common congenital HD
PFO doesn’t close in 25% (in RA)
But - congenital bicuspid AV is most common (1% popn)
Assoc w/ premature AS + AR ?ASD.VSD
AF & stent - what Rx
DAPT is fine (and should be P2Y12 like Clopidogrel, not aspirin)
After 12 months - single agent AC
If needing triple therapy initially (w/ aspirin) - don’t continue beyond first month
Cardiac amyloid - types
1) AL (light chains)
2) Wild type ATTR (transthyretin) - “senile”
- AA is rare & doesn’t cause cardiac amyloid
- Inherited ATTR mutation amyloid DOESN’T CAUSE
- AL is worst pronosis
- Wild type has Tafamidus Rx to stabilies the transthyretin & slow the deposition which improves ACM & QOL
Ix cardiac amyloid
Bloods: SFLC, SPEP
BMAT
Mass spec - gold std
Nuclear HDL amyloid scan helpful
