Cardiology Flashcards
Most common cause of dilated cardiomyopathy
50% Idiopathic
46% myocarditis (adeno, entero, HHV6/coxsackie, CMV)
35% genetic (mainly neuromuscular disease)
Most common cause of HOCM
30-60% inherited- AD mutations in sarcomeric proteins
- Troponin T mutations: beta-myosin heavy chain MYH7 and myosin binding protein C MYBPC3
- 50% spontaneous
HOCM associated syndromes
Noonan, BWS, LEOPARD, Friedrich Ataxia
Echo findings in obstructive HOCM
HOCM - systolic anterior motion (SAM) of the mitral valve against the hypertrophied septum
Treatment of HOCM
Exercise restriction, B-blockers, myotomy, antiarryhmics, ICD if high risk
Features of restrictive cardiomyopathy, prognosis?
Diastolic dysfunction with normal LV thickness
- Biatrial enlargement on Echo
- Poor prognosis, progressively worsens
- Rare 5% of childhood CM
- DDx constrictive pericarditis
Features of arrythmogenic RV cardiomyopathy
RV myocardium replaced by fatty/fibrous tissue, systolic bulging of RV wall
Pathophys of CCF- compensatory mechanisms heart/kidney
Decreased SV + CO
- Ventricular dilatation/hypertrophy
- Increased EDP/impaired filling (eventually SV cannot increase and plateaus)
- Increased SNS activation- HR & contractility ^ - damages myocardium chronically
- Dec RBF = inc RAAS (Ang 2 = inc Na/H20 reabs/vasoconstriction- promotes myocardial fibrosis)
DDx 12wk baby presenting with failure
VSD, ALCAPA
Rejection prevention in heart transplant?
Triple therapy: CNI (tacro/evero/sirolimus) + cyclosporin/antimetabolite/WBC enzyme inhibitor (AZA/MMF/6MP) + prednisolone
Most common cause of post transplant infection
CMV 25%
- consider IV gancyclovir prophylaxis if donor CMV +ve
Difference in pathophys acute cellular vs humoral vs chronic transplant rejection
- Acute cellular: T cell mediated, may have antibodies (ATGAM, OKT3)
- Acute humoral: alloantibodies to HLA/endothelial antigens (complement staining on Bx)
- Chronic: diffuse immune mediated, cause unknown
PHTN: common vasodilators
- NO (endothelial release) - increases cGMP, diffuses into smooth musc to vasodilate, PDE breaksdown, PDE inhibitors (i.e sildenafil) ^ vasodilation
- Arachadonic acid pathway- prostaglandin I2/prostacyclin
- Adenosine
- Oxygen
PHTN: vasoconstrictors
- Hypoxia potent vasoconstrictor (pulm oedema, PE, lung compression)
- ET-1
- Thromboxane A2
- Vasoconstriction from SNS overactivity
Features of Eisenmengers
Shunt reversal R-L in acyanotic lesion - VSD classical, also ASD, AVSD/ECD, PDA
- Influenced by pulm pressure, PBF & hypoxia
- Grade 1-5 based on severity of small arteriolar obstruction
- Usually 2nd/3rd decade, T21 earlier
- Resistant to medical Mx
Risk factors/causes of PPHN
MAS 41%, pneumonia/RDS 15%, CDH 10%, pulm hypoplasia 5%, idiopathic 20%
Causes of PPHN
- Vasoconstriction with normal vasculature
- Alveolar hypoxia- MAS, HMD, CNS hypoventilation
- Birth asphyxia, shock
- Infections
- Polycythemia - Arteriolar hypertrophy
-Intrauterine asphyxia
- Maternal meds - Developmentally abnormal vasculature
- CDH, pulm hypoplasia
Most common infective endocarditis organisms
Prev >90% strep viridians, staph aureus & enterococci
Rise of HACEK
- Haemophilus
- Actinobacillus
- Cardiobacterium
- Eikinella
- Kingella
S.Viridians most common after dental surgery
Staph most common post op
Enterococcus most common post GI/GU surgery
Indications for IE prophylaxis
- Prev IE
- Prosthetic heart valves
- Unrepaired cyanotic CHD, CHD with prosthetic device/residual defect
- Heart transplant patients
- ?ASD/repaired ASD/PDA
Pre-op (dental, mouth/skin/MSK)
high risk- as above
Not indicated in low risk- acquired valve disease, pacemakers, repaired acyanotic CHD
Indications for IE prophylaxis
- Prev IE
- Prosthetic heart valves
- Unrepaired cyanotic CHD, CHD with prosthetic device/residual defect
- Heart transplant patients
Pre-op (dental, mouth/skin/MSK)
high risk- as above
Not indicated in low risk- ASD
Most common cause of myocarditis, mortality risk assoc.
Viral- adeno, entero, echino
Up to 75% mortality
Rx bed rest, high dose IVIG, CCF meds (diuretics, inotropes), ACEi/antiarrythmics
Most common cause of myocarditis, mortality risk assoc.
Most common cause of pericarditis by age group
Infant/young children: viral
Older children: ARF, bacterial (S.Aureus, H.Influenza, N.Meningitidis)
Mx of constrictive pericarditis and outcomes
Pericardial resection - improvement in 75% of patients
Features of KD
Fever >5days + 4/5 of
- Conjunctivitis: bilateral/non purulent
- Lymphadenopathy: unilateral/tender
- Rash: polymorphous
- Mucosal changes: oral hyperemia, strawberry tongue
- Extremity changes: hyperemia -> desquamation
Features of incomplete KD
Fever >5d + 2-3 of:
- irritability without explaination
- unexplained aseptic meningitis
- shock
- cervical adenitis not responsive to ABx
Lab findings suggestive
- anaemia
- raised plts >450, WCC >15, urine WBC >10
- low albumin <30
- abnormal echo
Incidence of coronary artery aneurysm
(incidence if treated with IVIG)
15-25%
With IVIG 4%
High risk for CAA with KD
Signs of shock
Age <12 months
Asian ethnicity
ALT > 100
Alb < 30
Evidence of cardiac involvement at presentation
Timing of echo for CAA monitoring in KD
At presentation (this should not delay initiation of treatment)
2 weeks
6 weeks
Major criteria for ARF
ACHES
Arthritis
Chorea
Heart-carditis
Erythema marginatum
Subcut nodules
Minor criteria for ARF
TAPE
Temp >38
Arthralgia
PR prolongation
Elevated CRP/ESR >30
Most common presenting feature of ARF?
Arthritis
Nb: Chorea rare, but up to 25% in ATSI adolescent females
Duration of benzathine penicillin (IM 4/52) prophylaxis in ARF?
10yrs since last episode ARF or 21yrs of age, whichever longer…. OWCH
Management of VT?
Pulse present- amiodarone 5mg/kg/30mins
No pulse- Synchronous DC shock 2J/kg > 4J/kg
Management of VF
Shockable rhythm
- 4J/kg synchronous shock
- CPR 2mins- pulse check
- Adrenaline 10mcg/kg after 2nd shock then every 2nd loop CPR
- Amiodarone 5mg/kg after 3rd shock
Management of SVT
Vagal stimulation- ice/vasovagal
If haemodynamically stable: Adenosine - 100, 200, 300mcg/kg
If shocked: synchronous DC shock 1J > 2J/kg
Most common cause of congenital complete heart block
Neonatal lupus 60-90% (autoimmune Abs cross placenta)
Congenital heart disease 25-33%- L-TGA, single ventricle pathologies, polysplenia
Causes of long QT
A: Anti Arrhythmics – amiodarone, sotalol, quinidine
B: Anti Biotics – macrolides, bactrim, erythromycin
C: Anti- psyChotics – haloperidone, risperidone, chlorpromazine
D: Anti – Depressants – tricyclics
E: Low Electrolyes/ Endocrine: low Ca, low K, low Mg, hypothyroidism
F: Anti-Fungals: fluconazole
G: Bad Genes
H: Anti Histamines – terfinadine, astemizole
Genetic/Syndromic long QT
K+ - 30% KCNQ1/ 30% KCNH2 - triggered by emotion/exercise
Na2+ channel- 10% SCN5A
Syndromes:
Roman Ward (AD)- most common, multiple genes- LQTS 1-3,5,6,9-15
Jervell-Lange-Neilsen (AR) KCNQ1/NE1- SNHL
Anderson-Tarwil (AD) KCNJ2- muscle weakness/dev delay
Timothy (AD)- L Type Ca2+ channel (CACNAIC)- webbed digits, developmental delay, hypoglycemia, immunodeficiency
Symptoms/presentation of LQTS
Asymptomatic/positive FHx 60%
Symptoms = syncope (26%), seizure (10%), cardiac arrest (9%), pre-syncope, palpitations (6%), deafness (5%)
Triggers:
LQT1 – attacks during exercise/ swimming, broad based T waves
LQT2 – response to sudden noise, low amplitude T waves
LQT3 – attacks during rest/ sleep
Indications for VSD repair
- Qp:Qs >2:1
- CCF not responding to MMx
- Symptoms despite max therapy
- T21 (early repair)
Contraindications:
- PVR >12 WU
Ficks formula
Qp:Qs = (SaO2 - MvO2) / (PvO2 - PaO2)
SaO2 = Aortic SpO2
MvO2 = mixed venous SpO2 (SVC or RA)
PvO2 = Pulmonary vein SpO2
PaO2 = Pulmonary artery oxygen SpO2
Murmur, ECG & CXR findings: VSD
Pansystolic- LLSB
ECG: LVH/BVH if severe
CXR: Increased PA markings, LA/LVH
Murmur, ECG & CXR findings: AVSD
Murmur: pansystolic/holosystolic LLSB (MR) + diastolic rumble, narrow split S2
CXR: cardiomegaly, increased PA markings
ECG: BVH/superior axis, prolonged PR
Murmur, ECG & CXR findings: ASD
Murmur: Ejection systolic murmur LUSB + click, widely split fixed S2 (prolonged closure of the pulmonary valve)
CXR: Increased PA markings
ECG: RVH + RBBB
Murmur, ECG & CXR findings: PDA
Murmur: machinery murmur/continuous LUSB
ECG: BVH
CXR: L) enlargement
Murmur, ECG & CXR findings: PAPVR
Murmur: Ejection systolic murmur LUSB- +/- click, fixed S2 if assoc with ASD
ECG: RVH
CXR: R) enlargement, increased PA markings, scimitar sign
Murmur, ECG & CXR findings: TAPVR
Murmur: Ejection systolic murmur LUSB + diastolic rumble LLSB, split + fixed S2
ECG: RAH/VH & RAD
CXR: R) enlargement, snowman sign
Murmur, ECG & CXR findings: AS
Murmur: Systolic murmur-ESM RUSB, Early crescendo LLSB if bicuspid + paradoxical split S2 (expiration) if severe
ECG: LVH/N
CXR: N/dilated AO
Murmur, ECG & CXR findings: PS
Murmur: Ejection systolic LUSB- radiates to back, wide split A2/P2 (prolonged closure of the pulmonary valve.)
ECG: RAD/RVH
CXR: Enlarged main PA/ cardiomegaly & increased PA markings if severe
Murmur, ECG & CXR findings: coarctation
Murmur: Ejection systolic- RUSB/LLSB- paravertebral interscapular ares (heard best posteriorly)
- single loud S2
ECG: RVH/RBBB- LVH if severe/asymptomatic
CXR:Cardiomegaly/pulm oedema if symptomatic, rib notching if asymptomatic
Murmur in ASD + cause?
Systolic, loudest in LUSE (flow across PV), widely split S2- due to RBBB +/- diastolic murmur in large ASD (flow across TV)
Features of complete AVSD & Mx
Primum + inlet VSD + abnormal MV/TV
- Early CCF 1-2mo post birth, PVOD 6-12mo, DEATH 2-3yrs
- Holosystolic murmur, diastolic murmur + narrow split S2/loud S1
- Superior axis ECG
- BVH, ^ pBF & PA on XR
- Rx surgery 2-4mo,
T21 at worse risk
Timing of surgical Mx for VSD, ASD & indications
ASD: >8mm unlikely to close (3mm 100%, 3-8mm >80%), device closure at 2-4yrs - if Qp:Qs >5:1,RV overload/CHF
VSD: inlet/outlet do not close- device close 6-12mo- if Qp:Qs >2:1, CHF, PVOD
Timing of VSD closure
60% small muscular VSD close (<8y)
30% small perimembranous VSD close (<5y)
Inlet + outlet do NOT close
Mx severe ASD
PGE infusion
Balloon valvuloplasty
- Indications: duct dependent, ↓ LV function, gradient >50 mmHg
Surgical
- Norwood procedure + Fontan if critical AS with hypoplastic L) heart
- Ross procedure: AV replaced with PV
- Artificial valve
most common cause aortic stenosis /associations?
Valvular (75% BV)
– Turner (bicuspid AV)
Supra-valvular
- William
- Familial hyper-chol
Findings in co-arctation
Symptomatic - stenosis/reduced BF past aorta, RVH
Asymptomatic- collaterals develop
UL>LL BP 15-20mmHg
Reduced/absent femorals
ESM- RUSB & LLSB- continuous murmur if collaterals
Rib notching on CXR if collaterals
ECG: LAD/LVH - asymptomatic RAD/RVH/RBBB if symptomatic
Syndromes associated with MVP
Marfan
EDS
OI
Stickler
PCKD (adults)
Klinefelter
Conditions associated with MR
Rheumatic fever, KD
MPS- Hurler syndrome
Syndromes associated with AR
Marfan, Ehler-Danlos, MPS- Hurler Sx
Cyanotic lesions with decreased PBF
TOF
Tricuspid/pulmonary atresia
Ebstein anomaly
DORV
Cyanotic lesions with increased PBF
D-TGA/cc-TGA, TAPVR, Truncus ateriosis, DILV, HLHS
What congenital heart defect is maternal lithium use associated with?
Ebsteins
What syndrome is truncus arteriosus associated with
Di George- 30%
Indications for 3x stage Fontan
Dominant RV: HLHS
Dominant LV: DILV, PA + intact VSD, Tricuspid atresia
Other Unbalanced AVSD, Complicated DORV (no PS)
Stages of Fontan
- Norwood (1wk): Ao/PA shunt, BT shunt (RV-PA), Pulm banding if increased PBF, DKS if-
- Glenn (3-6mo): SVC to PA, removal BT shunt- when shunt fails/dec SpO2
- Fontan (2yrs): IVC to PA
CHD associated with VACTERL
most commonly associated with VSD however ASD, hypoplastic left heart, transposition of the great arteries and tetralogy of Fallot also occur.
CHD associated with Alagille (JAG/NOTCH)
Peripheral pulmonary stenosis (others include tetralogy of Fallot, septal defects, coarctation of the aorta)
CHD associated with Williams (7q11.23del)
Supravalvular aortic stenosis (70% of cases), pulmonary valve stenosis
ECG findings in LQT1 syndrome (KCNQ1)
Most common genotype- 35% LQTS
ECG: polymorphic VT (consistent with initial rhythm strip) classically triggered by exercise or emotional events.
ECG findings in Brugada syndrome
Rare cause of SCD- defect in myocardial Na channels
‘coved’ ST elevation in V1/V2 and pseudo-RBBB.
Tachy-arrhythmias may be triggered by fever
ECG findings in LQT2 syndrome
Second most common genotype (25-35%). Arrhythmia is classically triggered during sleep/rest
ECG: polymorphic VT
D-TGA pathophys & repair?
5-7% of defects, M>F 3:1
Aorta from RV (cyanotic)
PA post from LV
- may have fixed/dynamic LVOT
Duct dependant- PDA, VSD, ASD/PFO
Sx: cyanosis at birth (does not respond to O2), tachypnoea, CCF within first few weeks, death <6mo if not treated
- If VSD/PDA more likely to develop CCF
No murmur unless VSD/LVOT, loud S2
ECH: R) axis/RVH/BVH
CXR: cardiomegaly, ^ PBF, ‘egg on a string’
Rx: PGE1- keep duct open
Surgery- Arterial switch
- May also need initial BT shunt if severe PS/subaortic stenosis = VSD
Pathophys/Rx of L-TGA
L/cc-TGA 1% of patients
Ventricles switched
RA-LV (PA), LA-RV (Ao)
Physiologically normal but other associated abnormalities:
- 80% have VSD
- PS 50%, TR 30%
- AV block/SVT & reentrant tachy common
- Dextrocardia 50%
- Inverted CA
Asymptomatic unless other defects
May present in first few months if PS + VSD = cyanosis, large VSD = CCF
Murmur: nil, loud S2
If VSD; holosystolic LLSB
If PS: ESM RUSB
If TR/large VSD, apical rumble
ECG: absent Q waves V5/6, AV block, WPW
CXR: straight cardiac border
Rx: antiarrythmics/CCF rx
If PS+VSD - BT shunt
If large VSD - PA banding
May also need anatomic repair (Senning)/Fontan if single ventricle patho
Cardiac lesions with increased risk of SVT/AVRT
cc-TGA, Ebsteins, HLHS, HOCM, Harmatoma (TS)
Patho/Rx TOF
5-10% of cardiac defects (most common)
- Large VSD
- RVOT (infundibular stenosis 45%, pulmonary valve 10% or both 30%)
- RVH
- Overriding aorta
(VSD & RVOT mainly contribute to pathology)
Patho/Rx TOF
5-10% of cardiac defects (most common)
- Large VSD
- RVOT
- RVH
- Overriding aorta
Well baby with continuous murmur at time of birth- Dx?
Coronary artery fistula
- 50% of CA abnormalities
- Can fistulate between heart/PA
- 90% terminate in R)heart (mimic ASD- ejection systolic murmur LUSB, split/fixed S2)
- PA - similar to PDA (wide PP, continuous murmur LUSB, LVH)
- LA - similar to MR (pansystolic murmur apex, LVH)
- LV- similar to aortic valve regurg (diastolic murmur LLSB)
PDA murmur NOT present at birth
Lesions with prolonged PR
CHD: AVSD, Ebsteins
Acquired: ARF
Congenital heart block
Lesions with superior axis
NATE (C)
Noonans- supravalvular pulm stenosis
AVSD/primum ASD
Tricuspid atresia
Ebsteins
CC-TGA
Lesions with single S2
Abnormal valve:
- Obstructive: PS/AS/atresia/tricuspid atresia
- Eisenmengers/large VSD
Abnormal valve position:
- Truncus
- TOF
- TGA (both)
- HLH
+ severe PHTN
Exam findings in PHTN?
RV heave
Narrowly split or single S2 (P2 closes early)
TR = holosystolic murmur
PR = early diastolic murmur
Hepatomegaly
Peripheral edema
Presenting features of LQT1,2,3?
LQT1 (KCNQ1)/ Jervell and Lange-Nielsen syndrome– attacks during exercise/ swimming, broad based T waves
LQT2 (KCNH2) /Roman-Ward syndrome– response to sudden noise, low amplitude T waves
LQT3 (SCN5A) – attacks during rest/ sleep
Murmur heard right infra-clavicular region, associated scar. Hx of cyanotic heart disease
BT shunt- stage 1 of Norwood procedure, redirects blood flow to lungs
Continuous/machinery-like murmur at LUSE/left infra-clavicular, with bounding pulses.
PDA – persistent connection between aorta and pulmonary artery
Pan-systolic, LLSE, harsh
VSD
Crescendo-decrescendo ejection systolic in LUSE peaking in early/midsystole with fixed splitting of S2
ASD
Long, harsh systolic murmur with cyanosis
TOF
Blowing, holo-systolic at LLSE, increasing with inspiration and reducing with Valsalva
TR
Holosystolic at the apex, radiates through to back or clavicular area (with
systolic click in MVP)
MR
Qp:Qs >1
L > R shunt
Excess BF in lungs
- High arterial, low central venous O2
Qp:Qs <1
R > L shunt
Excess BF in body (bypasses lungs)
Qp:Qs <1
R > L shunt
Excess BF in body (bypasses lungs)
- Reduced tissue (arterial) oxygen delivery
First, second and third most common valve to be affected in ARF?
Mitral (65-70% of patients)
Aortic valve (25%)
Tricuspid valve (10%)
Causes single loud S2- features of Dx?
Abnormal position of arteries
(Cyanotic)
- Truncus
- Tricuspid atresia - LVH/superior axis
- TOF- BVH/RAD
- D-TGA- RAH/RVH
(Acyanotic)
- HLHS - RVH
- TOF- RVH/RAD
- cc/L-TGA- Q waves in RHS/limb leads
Abnormal PA/Ao
- Ao/PA stenosis
- Pulm atresia- RVH
- Large VSD/Eisenmenger
Causes of prolonged PR
AVSD
Ebstein’s anomaly
Acute rheumatic fever
Congenital heart block
Causes of WPW
Ebstein
Hamartoma (eg. TS)
HOCM
Single ventricle
ccTGA
Causes of deep Q waves
HOCM
ccTGA (V1)
Anomalous L coronary artery (V5 + V6)
Causes of deep Q waves
HOCM
ccTGA (V1)
Anomalous L coronary artery (V5 + V6)
Dx ECG
sinus tachycardia and non-specific T-wave and ST-segment changes
QRS/QT prolongation
Low voltage QRS (<5mm in precordial leads)
Pathological Q waves
Ventricular arrhythmias (can be ectopics or VT)
AV block
Dx ECG?
Large QRS due to hypertrophied muscle
T wave inversion/ST changes = unhealthy myocardium
Dx ECG?
DCM- weak/floppy myocardium
- QT prolongation
- Low voltage QRS
- T/ST wave changes- unhealthy myocardium
- Ventricular ectopics/AV block
Duration for prolonged QTc? + suggestive Hx?
In boys, a prolonged QTc is >450ms
In girls a prolonged QTc is >460ms.
Syncope, FHx SCD/long QT, meds (anticonvulsants/depressants/psychotics, ABx, antiemetics, antihistamines, antiarrythmics, antifungals)
Deafness- LQT5
Dx this ECG?
Normal baseline EXG
Inherited condition affection Ca2+ influx channels, high adrenaline states unmask
- Exercise
- Stress
AVOID DEFIB/ADRENALINE
Dx this ECG?
Brugada
- Inherited channelopathy
- Common in males/carb consuming cultures (Asia/Western)
Dx this ECG?
ALCAPA- pathological Q waves 1, AVL, V6
Causes hypertrophic CM (metabolic)
Lysosomal storage & mucopolysaccharidoses
- Hurler/Hunter
- I-Cell Disease
Glycogen storage diseases
-Pompe
Causes dilated CM (metabolic)
Organic acidemias
- Homocysteinuria
FAO disorders
- MCAD
