Cardiology Flashcards
Which are duct dependent cardiac lesions?
Present with collapse following duct closure.
Critical aortic stenosis / pulmonary stenosis
Hypoplastic Left Heart
Interrupted aortic arch
Coarctation of the aorta
Pulmonary / Tricuspid Atresia
Transposition of great artery.
TOF
Presentation of Atrial Septal Defect
- Small = Well. Large = Heart failure, recurrently LRTI / wheeze
- Murmur = ULSE systolic murmur. Fixed wideset HS II
- ECG = RBBB, superior QRS
- CXR = cardiomegaly, HF
- Associations= T21, foetal alcohol
Management ASD
Surgical intervention if significant (HF, RV dilatation)
Presentation of Ventricular Septal Defect
- Small = Well, murmur
- Large = HF, faltering growth, LRTIs
- Murmur = LLSE loud systolic murmur + thrill (quieter if large)
- ECG = Biventricular hypertrophy
- CXR = HF
Management of VSD
- Small will close spontaneously
- Medical - diuretics, high calorie diet
- Surgical closure by 12m to avoid Pulm. HTN
What is Eisenmenger syndrome and how does it present?
- VSD with left to right shunt
- Increased pulm. BF –> thick walled and resistant arteries and pulm. HTN
- 10-15y, reversal of shunt –> right sided heart failure and cyanosis
Presentation of PDA
- More in prematurity
- Continuous machinery murmur below left clavicle
- Bounding / collapsing pulses
- Wide pulse pressure
- Swinging sats
- Large - HF, pulm. HTN, recurrent LRTIs
Presentation of Aortic Stenosis
- Causes: Bicuspid valve, rheumatic fever. Associated with William’s and Turner’s
- Mild: ASx
- Neonate: Shock, HF, sudden death
- Older: Chest pain, syncope
- ESM right sternal edge –> carotids + carotid thrill. More prominent exhaling/ sitting up
- CXR = prominent LV
- ECG = LV Hypertrophy
Management of Aortic stenosis
- Neonate - prostaglandins
- Surgical repair - open / balloon
Presentation of Coarctation of the Aorta
- Early D1 collapse
- May be ASx until duct closes a few days later
- HF, absent pulses, radio-femoral delay, BP 20 mmHg lower in lower limbs
- Usually no murmur (may have ESM between shoulder blades) but may have murmur of PDA
- Older Dx - Chest pain, headaches, HTN, visual changes.
- ECG normal
- CXR= cardiomegaly
- Associated with Turner’s
Management of Coarctation of the Aorta
Prostaglandin infusion
Stent / surgery
Presentation of Pulmonary Stenosis
- Association: Noonan’s, William’s, Agille
- Mild - ASx
- Severe = collapse soon after delivery –> right to left shunt via PFO
- ESM LUSE –> back. Ejection click.
Management of Pulmonary stenosis
Prostaglandin infusion
Surgical repair
Presentation PFO
Usually closes 24 hours
Usually ASx with no murmur
Cardiac anomaly associated with Di George
Interrupted aortic arch, duct dependent VSD
Presents: Shock, absent femoral pulses
Presentation of transposition of the great arteries
- Cyanosis and collapse day 2 following PDA closure
- Less severe if also ASD / VSD allowing mixing
- CXR = “egg on side”
- No murmur. Loud HS II
Management of transposition of the great arteries
Prostaglandins
Surgery - initially create ASD –> arterial switch procedure
What are the 4 elements of Tetralogy of Fallot?
- Large VSD
- Overriding aorta (right to left)
- Right ventricular outflow obstruction (subpulmonary stenosis)
- Right ventricular hypertrophy
Presentation of Tetralogy of Fallot
- Cyanotic spells on exertion / agitation
- HF - SOB and pallor
- Clubbing
- Harsh ESM LSE
- CXR = boot shaped
- ECG initially normal –> RVH
Tetralogy of Fallot management
Prostaglandins
Hypercyanotic spells: O2, propranolol, knees to chest
Surgery at 6m
Presentation and management of hypoplastic left heart
- AN Dx or Sick ++ at birth with profound cyanosis, weak / absent pulses
- Difficulty feeding, faltering growth
- CXR - Cardiomegaly
- ECG - weak / absent QRS
- Tx: prostoglandins, surgery
What is Ebstein Anomaly?
Abnormally formed tricuspid valve –> not fully closing –> RA dilatation and HF
What murmur would you expect with mitral regurgitation?
Pansystolic –> radiates to axilla
What murmur would you expect with Aortic regurgitation?
Early diastolic. LLSE / URSE
What murmur would you expect with mitral stenosis?
Mild diastolic at apex, worse rolling to left
How is cardiac output calculated?
CO = SV x HR
What is the Frank Starling Law?
Energy of contraction is proportionate to the initial length of cardiac muscle fibre
More stretch –> most contractility –> increased CV and CO
What is Laplace Law?
Cardiac wall tension = (Pressure diff x radius) / wall thickness
Ie Dilated cardiomyopathy –> more energy required
What do each of the segments from ECG represent in cardiac cycle?
- P waves = atrial depolarisation
- PR interval = pause before reaching ventricles
- QRS = Ventricular depolarisation
- ST segment = Isoelectric
- T wave = ventricular repolarisation
What is a normal axis on an ECG?
-30 - 90
Management of SVT
- Vagal manoevers
- IV adenosine (opening ACh-K+ channels and blocking Ca++ influx) –> AVN block
- Amiodarone
- Electrical cardioversion
Maintenance: Flecainide, sotolol, digoxin, propranolol in WPW
ECG sign in WPW
Delta wave (slurred R wave)
Short PR
Widened QRS
Treatment for tachyarrhythmia in WPW
1st line = IV Amiodarone
2nd line = Flecainide.
Pathophysiology of WPW
Tachyarrhythmia due to accessory pathway (Bundle of Kent) for conduction of electricity between atrium and ventricles. Re-entry pathway –> paroxysms of tachycardia.
Definition Long QT syndrome
> 440 ms
Causes of congenital Long QT Syndromes
Delay in K+ out and Ca2+/ Na+ in. CHANNELOPATHIES.
- LQT1. Slow K+ out. Worse on exercise. Link deafness. Broad T wave.
- LQT2. Slowed K+ out. Flatter T wave. NB stress / emotion
- LQT3. Delay Na+ in. Peaked T wave. Sleep trigger
Causes of acquire Long QT Syndrome
= Prolonged repolarisation
- Drugs - antipsychotics
- Electrolyte balance - low K+/ Na+/ Ca2+/ Mg2+
- Anorexia
- Metabolic / neuro conditions
Presentation of Long QT syndrome
- ASx +/- FHx
- Syncope ESPECIALLY WITH EXERCISE / EMOTION
Causes of myocarditis
= inflammation and necrosis of myosites
Viral - coxsackie, adenovirus, EBV, CMV, HPV 6
Drugs
Toxins
AI
Diagnostic criteria of Rheumatic Fever
Recent Group A Beta Haemolytic Strep. infection + 2 major or 1 major + 2 minor
- Major = Carditis, arthritis, erythema marginatum, Sydenham Chorea, s/c nodules
- Minor = Arthralgia, heart block, fever, raised inflammatory markers
–> Anti-inflammatorys +/- Abx
Diagnostic criteria for Infective Endocarditis
Dukes = 2 major OR 1 major and 3 minor OR 5 minor
- Major = 2x BC with: Staph. aureus, strep. viridans / bovis. Echo findings (vegetation, abscess, dehiscence valvw).
- Minor = Predisposition, fever >38, vasc. phenomenon, immunological phenomenon, +BC (not typical organism), Echo but not major findings
Presentation and management of familial hypercholesterolaemia
= Genetic (AD) LDL receptor defect
- FHx early cardiac death
- Raised total cholesterol without rise in TG. NB genetic testing
- Tx = statin
Pathophysiology HOCM (Hypertrophic Obstructive Cardiomyopathy)
Presentation: Chest pain, fatigue, palpitations
Dynamic Murmur due to dynamic obstruction of the LVOT.
Manoevers that increase pre-load eg standing to squatting, passive leg raise, fill the ventricle more –> relieve obstruction –> increase size of ventricle –> open outflow tract –> quieter murmur.
Opposite happens in Valsalva, squatting to standing which reduce the preload.
Side effects of Prostoglandin infusions
Hypotension / Bradycardia
Apnoeas
Flushing
Cardiac catheter data: Normal 02 sats by area
- Vena cava, right atrium, right ventricle, pulmonary artery = 75%
- Left atrium, left ventricle, aorta = 98%
Cardiac catheter data: Normal pressures by area
- VC: 0-5
- RA: m=3
- RV: 25/3
- PA: 25/8
- LA: m=8
- LV: 110/8
- Aorta: 110/65
What is hyperoxic test?
Pre-ductal ABG taken after breathing 100% o2 for 10-15mins
If fixed = cardiac (right to left shunt)
If improved = respiratory
What is Blalock-Taussig shunt and when is it used?
- Connects subclavian artery to pulmonary artery
- Used if severe reduction to pulmonary flow - pulm. atresia, TOF
If re-cyanosed post procedure –> VQ scan
What is Fontan procedure?
Connects IVC/ SVC/ RA to pulmonary arteries –> bypasses RV
Use in tricuspid atresia, single ventricle, pulm. atresia
Complications: RHF, sick sinus syndrome, arrhtymias
What is Norwood procedure?
Used in HLH
Stage 1= links RV to aorta, PA divided, atrial septostomy. BT shunt.
Stage 2= Fontan procedure
What is Glenn procedure
Connects SVC to PA, shunt from Norwood removed
Cardiac condition associated with Freidrich’s ataxia
Hypertrophic cardiomyopathy
Cardiac conditions associated with Marfan’s
Aortic dissection
Aneurysm
Regurgitation
Cardiac condition associated with Tuberous Sclerosis
Rhabdomyoma
Presentation of cardiomyopathy
Chest pain
Syncope
Palpitations
SOB
Usually inherited
Signs of hypokalaemia on ECG
U waves
Increased p wave amplitude
Prolonged PR
Long QT (fusion of T and U)
