Cardio Part 2 Flashcards
What is hypertrophic cardiomyopathy (HCM) caused by?
sarcomeric protein gene mutations
Hypertrophied cardiomyopathy affects how many people?
HCM affects 1 in 500 people
What does HCM refer to? (Hypertrophied Cardiomyopathy)
- Cardiomyopathy refers to primary heart muscle disease – often genetic
- HCM refers to otherwise unexplained primary cardiac hypertrophy
- angina, dyspnoea, palpitations, dizzy spells or syncope
- LVOT (Left ventricular outflow tract) obstruction may be a feature
- HCM - septum or any part of the heart can be affected, it is primary hypertrophy, white area in myocardium - fibrosis scarring in the heart, big thick and stiff heart, diastolic heart failure as the heart cant fill properly, “histology”: myocytes in the heart has branching - wave get eveyrwhere for single contraction at the same time, in HCM, myocytes all over the place, myofibrillar structure is chaotic, myofibrillar disarray, fibrosis is electrical insulator, sometime reaches to muscle that has already repolarised - arrhythmic heart
What is Dilated cardiomyopathy (DCM) often caused by?
cytoskeletal gene mutations
Talk about DCM (dilated cardiomyopathy).
- DCM usually presents with heart failure symptoms
- DCM - LV/RV or 4 chamber dilatation and dysfunction
- DCM - present heart failure, heart is dilated, normal thin wall, terrible left ventricular function, the heart can barely see its pumping if the valve is not opening and closing
What is Arrhythmogenic Right/Left ventricular cardiomyopathy (ARVC/ALVC) usually caused by?
desmosome gene mutations
ARVC (arrhythmogenic right ventricular cardiomyopathy), fatty fibrosing replacement of the muscle, programmed replacement in the heart muscle, ECG has epsilon waves, late potential, a factor contributing to arrhythmia
What is the main feature of arrhythmogenic cardiomyopathy?
Arrhythmia
All cardiomyopathies carry an arrhythmic risk.
True/False?
True!
What is Inherited arrhythmia (channelopathy) usually caused by?
ion channel protein gene mutations
Talk about Channelopathies.
These usually relate to potassium, sodium or calcium channels
- Channelopathies include long QT, short QT, Brugada and CPVT (Catecholaminergic polymorphic ventricular tachycardia)- abnormally fast heartbeat, respond extremely well to beta blockers
- Channelopathies have a structurally normal heart
- Channelopathies may present with recurrent syncope
Why should we be aware of QT prolonging drugs?
they can kill people with long QT syndrome
Sudden cardiac death in young people is often due to?
an inherited condition
- If so this is most likely a cardiomyopathy or ion channelopathy
Sudden arrhythmic death syndrome (SADS) usually refers to ?
normal heart/arrhythmia
Talk about FH (familial hypercholesterolaemia).
- Familial hypercholesterolaemia (FH) is an inherited abnormality of cholesterol metabolism
- FH leads to serious premature coronary and other vascular disease
- Receptor issues, LDL receptor problems, massive risk of MI, Coronary artery disease, genetic, dominantly inherited, manifestation within the family will be different eventho all have the disease, age-related penetrance
Aortic aneurysm or dissection is often inherited.
True/False?
True!
What does Aortovascular syndromes include?
Marfan, Loeys-Dietz, vascular Ehler Danlos (EDS)
Marfan: Marfan syndrome is a disorder of the body’s connective tissues, a group of tissues that maintain the structure of the body and support internal organs and other tissues.
Loeys-Dietz syndrome is a connective tissue disorder that was first described in 2005. Most individuals with this disorder have craniofacial feature
Vascular Ehler Danlos: Vascular EDS (vEDS) is a rare type of EDS and is often considered to be the most serious. It affects the blood vessels and internal organs, which can cause them to split open and lead to life-threatening bleeding. People with vEDS may have: skin that bruises very easily.
Inherited Cardiac Conditions (ICC) are usually inherited dominantly or recessively?
- dominantly!
- offspring have 50% risk of inheritance
What are some life-saving treatments that are available for inherited cardiac conditions (ICC)?
(ICD, beta-blockers, statins, vascular surgery)
Is Naxos disease dominantly inherited or recessively inherited?
Naxos disease is a recessively inherited condition with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) and a cutaneous phenotype, characterised by peculiar woolly hair and palmoplantar keratoderma.
What happens to the heart when patient died from alarm clock ?
Long QT can trigger ventricular arrhythmia- alarm clock lmao
Hypertension is the major risk factor of?
> Stroke – ischaemic and haemorrhagic
Myocardial infarction
Heart failure
Chronic renal disease
Cognitive decline
Premature death
Hypertension can increase the risk of what kind of heart condition?
Atrial fibrillation (independent stroke risk)
Each 2 mmHg rise in systolic BP is associated with how many % of risk of IHD and Stroke?
7% increased mortality from ischaemic heart disease
10% increased mortality from stroke
What is the hypertension BP?
Suspected hypertension:
- Clinic BP 140/90 mmHg or higher
People with suspected hypertension are offered ambulatory blood pressure monitoring (ABPM) to confirm a diagnosis of hypertension
Talk about Stage 1 hypertension, Stage 2 hypertension and severe hypertension.
Clinic BP APBM
Stage 1 hypertension 140/90 and 135/85
Stage 2 hypertension 160/100 and 150/95
Severe hypertension SBP 180
or DBP 110
What is the general type of treatment for patients with primary hypertension?
Lifestyle modification
Antihypertensive drug therapy
Talk about initiating treatment in patients with hypertension.
Offer antihypertensive drug treatment to people aged under 80 years with stage 1 hypertension who have one or more of the following:
- Target organ damage
- Established cardiovascular disease
- Renal disease
- Diabetes
- A 10-year cardiovascular risk of 20% or greater.
Offer antihypertensive drug treatment to people of any age with stage 2 hypertension.
Talk about mechanism of BP control?
Cardiac output and Peripheral Resistance
- Interplay between:
a. Renin-Angiotensin-Aldosterone system
b. Sympathetic nervous system (noradrenaline) - Local vascular vasoconstrictor and vasodilator mediators
What can sympathetic nervous system do? (noradrenaline)
- increase renin in RAAS system
- increase peripheral resistance
- increase cardiac output
Talk about ACEi.
Main clinical indications
- Hypertension
- Heart failure
- Diabetic nephropathy
> Ramipril
Enalapril
Perindopril
Trandolapril
Main adverse effects:
1. Related to reduced angiotensin II formation
a. Hypotension
b. Acute renal failure
c. Hyperkalaemia
d. Teratogenic effects in pregnancy
2. Related to increased kinin production
Cough
b. Rash
c. Anaphylactoid reactions
Talk about Angiotensin II Receptor Blockers (ARB).
Main clinical indications
> Hypertension
> Diabetic nephropathy
> Heart failure (when ACE-I contraindicated)
- Candesartan
- Losartan
- Valsartan
- Irbesartan
- Telmisartan
Main adverse effects
- Symptomatic hypotension (especially volume deplete patients)
- Hyperkalaemia
- Potential for renal dysfunction
- Rash
- Angio-oedema
- Contraindicated in pregnancy
- Generally very well tolerated
Talk about Calcium Channel Blockers.
Main clinical indications
- Hypertension
- Ischaemic heart disease (IHD) – angina
- Arrhythmia (tachycardia)
L-type calcium channel blockers:
1. Dihydropyridines: nifedipine, amlodipine, felodipine, lacidipine
> Preferentially affect vascular smooth muscle
> Peripheral arterial vasodilators
- Phenylalkylamines: verapamil
> Main effects on the heart
> Negatively chronotropic, negatively inotropic - Benzothiazepines: diltiazem
> Intermediate heart/peripheral vascular effects
Talk about the adverse effect of Calcium Channel Blocker.
Due to peripheral vasodilatation (mainly dihydropyridines)
- Flushing
- Headache
- Oedema
- Palpitations
Due to negatively chronotropic effects (mainly verapamil/diltiazem)
- Bradycardia
- Atrioventricular block
Due to negatively inotropic effects (mainly verapamil)
- Worsening of cardiac failure
Verapamil causes constipation
Talk about Beta-adrenoceptor blockers (BB).
Main clinical indications
- Ischaemic heart disease (IHD) – angina
- Heart failure
- Arrhythmia
- Hypertension
Selectivity:
1. Beta 1 selective:
- metoprolol
- bisoprolol
2. Beta1/Beta 2 non-selective:
- propanolol
- nadolol
- carvedilol
3. Intermediate
- Atenolol
What is the main adverse effect of Beta-adrenoceptor blockers (BB)?
Fatigue
Headache
Sleep disturbance/nightmares
Bradycardia
Hypotension
Cold peripheries
Erectile dysfunction
Worsening of:
- Asthma (may be severe) or COPD
- PVD – Claudication or Raynaud’s
- Heart failure – if given in standard dose or acutely
Talk about diuretics.
Main clinical indications:
> Hypertension
> Heart failure
Classes:
> Thiazides and related drugs (distal tubule)
- BENDROFLUMETHIAZIDE
- HYDROCHLOROTHIAZIDE
- CHLORTHALIDONE
> Loop diuretics (loop of Henle)
- FUROSEMIDE
- BUMETANIDE
> Potassium-sparing diuretics
- SPIRONOLACTONE
- EPLERENONE
- AMILORIDE
> Aldosterone antagonists
What is the main adverse effect of diuretics?
Hypovolaemia(mainly loop diuretics)
Hypotension (mainly loop diuretics)
Low serum potassium (hypokalaemia)
Low serum sodium (hyponatraemia)
Low serum magnesium (hypomagnesaemia)
Low serum calcium (hypocalcaemia)
Raised uric acid (hyperuricaemia – gout)
Erectile dysfunction (mainly thiazides)
Impaired glucose tolerance ( mainly thiazides_
Talk about other non-common antihypertensives.
α-1 adrenoceptor blockers
Centrally acting anti-hypertensives
Direct renin inhibitor
Talk about standard treatment of hypertension.
Step 1: Under 55: ACEi/ARB
Above 55: Calcium Channel Blocker
Step 2: ACEi/ARB + CCB
Step 3: ACEi/ARB + CCB + Thiazide-like diuretics
Step 4: Resistant Hypertension
Consider addition of
Spironolactone, high dose thiazide-like diuretic, Alpha blocker, beta blocker, (others)
What are the different types of heart failure?
Heart failure due to left ventricular systolic dysfunction - LVSD
Heart failure with preserved ejection fraction (diastolic failure) – HFPEF
Acute heart failure / Chronic heart failure
Talk about Heart Failure.
Heart failure is a complex clinical syndrome of symptoms and signs that suggest the efficiency of the heart as a pump is impaired.
It is caused by structural or functional abnormalities of the heart.
Most common cause is coronary artery disease
Causes morbidity, mortality, hospital admissions and substantial cost
Most of the evidence for pharmacology is in chronic heart failure due to LVSD
Main benefit is with vasodilator therapy via neurohumoral blockade (RAAS - SNS) and not from LV stimulants
Talk about basic pharmacology of heart failure.
Symptomatic treatment of congestion:
> Diuretics (usually loop)
Disease influencing therapy – neurohumoral blockade
> Inhibition of renin-angiotensin-aldosterone system
> Inhibition of the sympathetic nervous system
a. First line:
> ACE inhibitors and beta blocker therapy
> Low dose and slow uptitration
b.Aldosterone antagonists
c. ACE-I intolerant:
-Angiotensin receptor blocker
d. ACE-I and ARB intolerant: Hydralazine/nitrate combination
e. Consider digoxin or ivabradine
Talk about nitrates in Chronic Heart Failure
- Arterial and venous dilators
Reduction of preload and afterload
Lower BP - Main uses
> Ischaemic heart disease (angina)
> Heart failure
Example: GTN Spray, GTN Infusion, ISOSORBIDE MONONITRATE
Talk about different type of coronary artery disease.
Coronary Artery Disease
- Chronic stable angina
Anginal chest pain
Predictable
Exertional
Infrequent
Stable
**** - Unstable angina / acute coronary syndrome (NSTEMI)
Unpredictable
May be at rest
Frequent
Unstable
**** - ST elevation Myocardial Infarction (STEMI)
Unpredictable
Rest pain
Persistent
Unstable
Talk about management of Chronic Stable Angina.
- Antiplatelet therapy
- Aspirin
- Clopidogrel if aspirin intolerant - Lipid-lowering therapy
- Statins (simvastatin, atorvastatin, rosuvastatin, pravastatin) - Short acting nitrate: GTN spray for acute attack
- First line treatment: Beta Blocker or Calcium Channel Blocker
- If intolerant: Switch
- If not controlled:Combine
- If intolerant or uncontrolled, consider monotherapy or combinations with: Long acting nitrate
Ivabradine
Nicorandil
Ranolazine
Talk about the management for Acute coronary syndromes (NSTEMI and STEMI).
- Pain relief: GTN spray
Opiates – diamorphine - Dual antiplatelet therapy:
Aspirin plus ticagrelor or prasugrel or clopidogrel - Antithrombin therapy: Fondaparinux
- Consider Glycoprotein IIb IIIa inhibitor (high risk cases): tirofiban, eptifibatide, abciximab
- Background angina therapy: beta blocker, long acting nitrate, calcium channel blocker
- Lipid lowering therapy: Statins
- Therapy for LVSD/heart failure as required: ACE-I, beta blocker, aldosterone antagonist
Talk about Vaughan Williams classification
of antiarrhythmic drugs.
Class I: Sodium channel blockers
Ia - disopyramide, quinidine, procainamide
Ib - lidocaine, mexilitene
Ic - flecainide, propafenone
Class II: Beta adrenoceptor antagonists
- propranolol, nadolol, carvedilol (non-selective)
- bisoprolol, metoprolol (β1-selective)
Class III: Prolong the action potential
- amiodarone, sotalol
Class IV: Calcium channel blockers
- verapamil, diltiazem
Talk about digoxin.
Digitalis Glycoside
Inhibit Na/K pump
Main effects are on the heart:
Bradycardia (increased vagal tone)
Slowing of atrioventricular conduction (increased vagal tone)
Increased ectopic activity
Increased force of contraction (by increased intracellular Ca)
Narrow therapeutic range
Nausea, vomiting, diarrhoea, confusion
Used in atrial fibrillation (AF) to reduce ventricular rate response
Use in severe heart failure as positively inotropic
Digoxin has two principal mechanisms of action, which are selectively employed depending on the indication:
- Positive Ionotropic: It increases the force of contraction of the heart by reversibly inhibiting the activity of the myocardial Na-K ATPase pump, an enzyme that controls the movement of ions into the heart. Digoxin induces an increase in intracellular sodium that will drive an influx of calcium in the heart and cause an increase in contractility. Cardiac output increases with a subsequent decrease in ventricular filling pressures.
- AV Node Inhibition: Digoxin has vagomimetic effects on the AV node. By stimulating the parasympathetic nervous system, it slows electrical conduction in the atrioventricular node, therefore, decreasing the heart rate. The rise in calcium levels leads to prolongation of phase 4 and phase 0 of the cardiac action potential, thus increasing the AV node’s refractory period. Slower conduction through the AV node carries a decreased ventricular response.
Why do we not use LV stimulants in heart failure?
Heart failure, sympathetic nervous system is gone, need RAAS, brain thought fluid or blood loss, then they will activate the sympathetic nervous system, NOT LV STIMULANTS!!
Relate spirinolactone with Gynaecomastia.
man has a small amount of breast tissue, but it can be enlarged, aldosterone antagonist - spirinolactone has a small amount of androgens
Sacubitril and Valsartan is a combination of drugs.
True/False?
True!
What is the difference between preload and afterload?
Preload is the initial stretching of the cardiac myocytes (muscle cells) prior to contraction. It is related to ventricular filling.
Afterload is the force or load against which the heart has to contract to eject the blood.
Why is plateau phase significant in membrane potential mechanism graph?
Refractory period
What are the 2 example of drugs that prolong QT interval and shouldnt be given to patients with long QT interval.
Amiodarone and sotalol
Talk about worm/helminth in general.
Adult worms cannot usually reproduce without a period of development outside the body. This may involve specific environmental conditions, animal hosts and/or vectors. Thus, although they usually produce innumerable larvae or eggs (which may themselves cause disease), the total worm burden cannot increase without constant re-exposure to infection. The PRE-PATENT PERIOD is the interval between infection and the appearance of eggs in the stool.
Helminths are divided into three groups, which three groups?
- Nematodes (roundworms)
- Intestinal
- Larva migrans
- Tissue (filaria) - some people consider this as a 4th group
- Trematodes (flatworms, flukes)
- Blood
- Liver
- Lung
- Intestinal
- Cestodes (tapeworms)
1. non-invasive (just sit in your gut)
2. invasive (invade your gut and go somewhere)
Talk about Intestinal nematodes.
- soil-transmitted varieties
- faecal-oral spread
Talk about Ascaris lumbricoides: the large roundworm.
- found worldwide, mainly tropics
- 600 cases per annum in the UK
- small intestine > produce egg, grow out of your gut to the lung, then go into trachae then swallow it
- Symptoms/signs: Loeffler’s syndrome (Löffler’s syndrome isa disease in which eosinophils accumulate in the lung in response to a parasitic infection)
- often asymtomatic, mechanical obstruction, biliary/pancreatic obstruction or malnutrition
- well known for disrupting surgical anastomoses after intra-abdominal durgery
- odd presentations-emerging from nose, perforated eardrum
- diagnosis: stool microscopy for eggs, seeing the worm itself
- Drugs: piperazine, pyrantel, mebendazole, levasimole
Talk about the hookworm.
- Ancyclostoma duodenale (west/SE asia, mediterranean, middle east)
- Necator americanus (USA, central/south america, central africa, india)
- small white worm, 1cm in length, life expectancy: 1-5 years
- cause of anaemia
- worm hooked in the bowel wall
- does not get into mouth
- clinical features:
> Ground itch - papules at the site of entry of larvae, eg on feet
> Pulmonary symptoms L mild due to pulmonary migration - Diagnosis: Stool microscopy for eggs
- Treatment: Iron supplement: pyrantel, mebendazole
Talk about Enterobius vermicularis(the pinworm or threadworm).`
- very common in UK
- only common helminth infestation in UK
- doesnt invade the body, get in from the mouth, get around FAMILY, get it from door knobs or paedetrician wards
- Life cycle: adult is resident in the large bowel
- the female emerges at the anus at night to lay egg at the perineum
- the egg become infectious after 4 hours,
- pruritis ani
- appendicitis
- vaginal penetration (infertility, endometriosis salpingitis
- paranasal sinuses
- diagnoses and treatment: microscopy and sellotape strip
- piperizine
Talk about Whipworms.
- might often cause rectal prolapse
- trichuris trichiura
- found worldwide
- 2-5cm long and live around a year PPP is 70-90 dyas
- adult is partly buried in the mucosal membrane of the large bowel
- eggs are passed into the environment in the host’s faeces
- found in the caecum, ascending colon
- clinicaql factorsL often asymptomatic, coexist with ascaris lumbricoides
- trichuriasis
- Diagnosis: stool microscopy
- Mebendazole, albendazole
Talk about Strongyloides stercoralis.
- cause strongyloidiasis
- worldwide
- adult is 2mm long, lies buried in the small intestinal mucosa
- PPP is 17-28 days
- crawl into skin, goes all over the body
- can AUTOINFECT - lavatory infection
- pruritis, pulmonary symptoms, gut symptoms (malnutrition), larva currens (skin rashes with auto infection, last <24 hours)
> Hyperinfection syndrome
- autoinfection associated and in immunocompromised state
- advance HIVv
- alcoholism
- immunocompromisation and corticosteroid therapy
- diarrhoea, weight loss, malabsorption, paralytic ileus, peritonitis, bacterial problems, (gram-negative septicaemia, meningitis, pulmonary disease)
- See no eosinophils, larvae found in stools and sputum (and potentially in all tissues)
- Diagnosis : stool- larval forms (eggs rarely seen), serology, eosinophila (swallow string, leave it in bowel, then take it out and see the larvae under the microscope)
Talk about Larva migrans.
- Visceral larva migrans (VLM)
- caused by Toxocara canis (dog roundworm) and T. cati (cat roundworm)
- Life cycle: a dead end, eggs are ingested> develop into larvae > invade tissue for 1-2 years (the organism can develop no further)
- Clinical: mainly a disease of children and see fever, hepatomegaly, eosinophilia, asthma (the first 3 signs and symptoms mimic leukaemia which is not true)
- Diagnosis:eosinophiliaa, serology
- Treatment: mebendazole, albendazole
Talk about Ocular toxocariasis (human).
- larvae become trapped in the retina
- see a granulomatous reaction
- Clinical: retinal mass, blindness (diff diagnosis: retinoblastoma)
- Diagnosis: serology/antigen detection in/of aqueous humour, biopsy (NB> no eosinophilia)
- Treatment: mebendazole, albendazole
Talk about Cutaneous larva migrans.
- creeping itchy skin eruption
- Due to dog hookworms
- ancycuistoma canium/braziliense
- lesions at the sites where larvae penetrate
- cutaneous larva migrans (hot, painful, extremely itchy)
Talk about Anisakiasis on endoscopy.
salmon/sushi, raw seafood, crustaceans, fish, squid, octopus
Talk about Dracunculus medinensis.
- the guinea worm or medina worm
- adult is up to 100 cm long, and lives for one year subcutaneously
- the incubation period is about one year, one case per year in the UK
- about 3 million cases per annum worldwide (eradication proposed by WHO)
- Blister in the leg, the worm will crawl out, the worm might discharge eggs
- other sites of emergence include the axillae and the vagina or any human orifice
- contaminated fresh water, crustaceans,
- solution: filter/sieve any drinking water through 2 layers of Muslin clothes, can prevent this disease
- can develop sepsis
- tetanus
- joint problems, peritomnitis
- diagnosis: ulcer promotes egg release
- treatment: wind out the worm
- mebendazole
- caduceus
Talk about Tissue Nematodes: The filaria.
- Wuchereria bancroftii
- Elephantiasis, endemic in the tropics, insect borne, adults live in the lymphatic system for like 30 years
- Diagnosis: demonstration of microfilaria in blood, needs to be taken at the right time of day (usually 2300pm to 0100am), varies with the geographical location, DEC provocation test, the larvae of these worm come up at night as more acidic pH sleeping at night, sucking your blood
- serology
- Treatment: DEC (Diethylcarbamazine) Ivermectin
> Onchocerciasis (aka hanging groin, river blindness, caused by fly), usually south africa
Loa loa
- mainly in West Africa
- that worm is under the surface of the
conjunctiva
- Tail details under microscope
Trichinella spiralis
- cause of trichinosis
- a zoonesis of rats that ciruclates in rats
and various carnivores, a “dead-end”
- Asymptomatic
- GI disturbances with transiet worm
development
- fever, headache, cough at eight weeks
- periorbital oedema etc
- brugia malayi
Talk about tapworms.
Tap worm
- 5-10m long, lives up to 30 years
- PPP is 12 weeks
- weight loss
- Life cycle: caught by eating undercooked beef containing cyts
- asymptomatic
- progllottids can emerge from human anus
- diagnosis: stools for eggs and proglottids
- Treatment: niclosamide, praziquantel
- Neurocysticercosis (pork tapeworm)
Talk about other tapworms.
Other tapworms
> echinococcus granulosus
- the dog tapeworm
- cause of hydatid disease (in humans, cattle, and sheep)
Echinoccosu multilocularis
- cause of alveococcosis
Diphyllobothrium latum
- the fish tapeworm
- cause of sparganosis
- vitamin B12 deficiency
Talk about blood flukes.
- schistosoma
- snail - to other species
- schistosomiasis
- adult fluke- 12cm long
- normal life span of 3-5 years (but up to 30 years)
- katayama fever (initial immune complex mediated illness 2-4 weeks)
- pathology - egg related, live in the liver, resemble alcholic cirrhosis, shistosoma haematobium
- can cuase bladder disease, massice fibrosis in the liver and squamous cell cancer in the liver not a transitional carcinoma
- calcified bladder
- renal calculi
- cor pulmonale (pulmonary hypertension, ccf)
- may cause obstructive uropathy - reversible if short duration and treated
- EXAM QUESTION
- Diagnosis - serology urine
- treatmentL complete vs incomplete cure
- praziquantel, isoquinoone metirphonate, osamniqione
- vaccine being developed
- control/prevention, reduced contamination byeducation, snanition, prevent egg transmisison
Why do we have to know about structural heart defect/congenital heart disease?
Fairly common
Although primarily a cardiac defect, implications for all sorts of other specialities
> Anaesthetics
> Dentistry
> Obs and gynae
> Paediatrics
> General practice
> Palliative care
> Radiology
> Haematology
> Respiratory medicine
> Neurology
What are the Care issues in congenital heart patients?
> Intellectual disability in 10%
Psychosocial issues
Transition
Explaining the lesion and the prognosis
Building independence/ self reliance
Talk about the genetic transmission probability of congenital heart defects.
Foetal recurrence
Background population 1%
Father with Congen HD 2.2%
Mother with Congen HD 5.7%
Tetralogy of Fallot 3%
AV septal Defect 10% - 14%
Foetal echocardiography at 18-22 weeks
What are some severe congenital heart defect that we would advise the patient to not go through pregnancy?
Severe risk
Maternal mortality expected in up to 50%
Pulmonary hypertension
Severe left heart obstruction
Systemic ventricular impairment (Ejection fraction < 30%)
Marfans syndrome with aortic root diameter > 47 mm
Moderate risk:
Unrepaired coarctation
Repaired coarctation with residual obstruction and hypertension
Repaired tetralogy of fallot with poor haemodynamic result, severe PR and RV dysfunction
Very severe PS
Moderate to severe aortic stenosis
Transposition of the great arteries (Mustard or Senning operations)ccTGA (congenitally corrected Transposition of the Great Arteries)
Well balanced single ventricle (depends on degree of cyanosis, and presence or absence of pulmonary hypertension)
Fontan circulation
Mechanical heart valves
Marfans syndrome with dilated aortic root >40mm < 47 mm
What are the 4 main defects in Tetralogy of Fallot?
- Ventricular septal defect
- Pulmonary stenosis
- Hypertrophy of right ventricle
- Overriding of aorta
The key issue is anterior dislocation of the septum below the pulmonary outflow which causes the other issues
Is patients with Tetralogy of Fallot blue? Why?
The stenosis of the RV outflow leads to the RV being at higher pressure than the left
Therefore blue blood passes from the RV to the LV
The patients are BLUE
How many percentage is Tetralogy of Fallot in congenital heart defects?
10%
then theres 1/1000 of prevalence
Talk about the surgical repair of Tetralogy of Fallot.
The Blalock-Taussig Shunt 1944
Walter Lillehei first ‘complete repair’ on a boy aged 11 – rebore the RVOT and patch VSD
1986 first repair in infancy
Now mostly repaired before the age of two years
Mostly do very well
Often get pulmonary valve regurgitation in adult life and require redo surgery
Talk about VSD.
Abnormal connection between the two ventricles
Common – 20% of all congenital heart defects – 1-4/1000 live births
Many close spontaneously during childhood
High pressure LV
Low pressure RV
Blood flows from high pressure chamber to low pressure chamber
Therefore NOT blue
Increased blood flow through the lungs
Talk about what are the effects of small and large VSD.
Large
Very high pulmonary blood flow in infancy
Breathless, poor feeding, failure to thrive
Require fixing in infancy (PA band, complete repair)
May lead to Eisenmengers syndrome
Small
Small increase in pulmonary blood flow only
Asymptomatic
Endocarditis risk
Need no intervention
Talk about clinical sign of small and large VSD.
Large
Small breathless skinny baby
Increased respiratory rate
Tachycardia
Big heart on chest X ray
Murmur varies in intensity
Small
Loud systolic murmur
Thrill (buzzing sensation)
Well grown
Normal heart rate
Normal heart size
Talk about Eisenmengers syndrome.
Initially theres left to right shunt due to the VSD
High pressure pulmonary blood flow
Damages to delicate pulmonary vasculature
The resistance to blood flow through the lungs increases
The RV pressure increases
The shunt direction reverses
The patient becomes BLUE
Talk about ASD.
- Abnormal connection between the two atria (primum, secundum, sinus venosus)
- Common
- Often present in adulthood
- Slightly higher pressure in the LA than the RA
- Shunt is left to right
- Therefore NOT blue
- Increased flow into right heart and lungs
Talk about the physiology in large and small ASD.
Large
- Significant increased flow through the right heart and lungs in childhood
- Right heart dilatation
- SOBOE
- Increased chest infections
- If any stretch on the right heart should be closed
Small
- Small increase in flow
- No right heart dilatation
- No symptoms
- Leave alone
NB. The shunt on small to moderate sized defects increases with age
