CARDIOLOGY Flashcards
Fetal circulation
Fetal lungs are underdeveloped ?
Not used during the intrauterine life.
Fetal circulation
Fetal organ involved in gas exchange
Placenta
Fetal circulation
Placenta consists of (Blood vessels)
- Umbilical vein (Carries oxygenated blood from the placenta)
- 2 Arteries (carries deoxygenated blood from fetus to mother)
Fetal circulation
The pressure in the LA and RA
RA>LA (Lungs are sending little to no blood to the LA)
Fetal circulation
Right atrium recieves blood from
- Venous blood from fetal systemic circulation
- blood coming from the placenta
Fetal circulation
Fetal circulation has… which is not seen in adult circulation
- Ductus venosus
- Ductus arteriosus
Foramen ovale
Fetal circulation
Foramen ovale is located
between the LA and RA
Fetal circulation
Ductus arteriosus is connected between
the pulmonary artery and the descending aorta
Fetal circulation
Fetal hypoxia causes
increased production of EPO
Cardiac cycle
Systole lasts… of the cardiac cycle
2/3
Cardiac cycle
Diastole lasts….of the cardiac cycle
1/3
Cardiac cycle
When the HR increases what happens to the diastole
Diastole shortens
Cardiac cycle
Mitral and tricuspid valves close during
Systole
Cardiac cycle
Aortic valve closes… than the pulmonary valve
earlier
Cardiac cycle
Physiological splitting of the 2nd HS
Change in intra- thoracic pressure during inspiration causes the IVC to drain more blood into the RA. More blood leads to delayed closure of the pulmonary valve later than the aortic valve
Cardiac cycle
Stroke volume
amount of blood pumped during a single contraction
Cardiac cycle
Ejection fraction
Percentage of blood pumped from each ventricle (~60-70%)
Cardiac cycle
Cardiac output
Amount of blood pumped out calculated per minute
CO=SVxHR
Neonatal circulation
Effect of lungs when the neonate cries soon after birth
Lungs expand.resistance to pulmonary blood flow falls and the volume of blood flowing through the lungs increase
Neonatal circulation
How does the ductus arteriosus close
After birth, aortic pressure will go up and the pulm pressure will go down. Oxygenated blood from aorta will go through the ductus arteriosus. Increased oxygen causes the Ductus to close within 96 hours after birth
Neonatal circulation
How does the foramen ovale close
- lungs expand after birth
- the resistance to pulmonary blood flow falls
- volume of blood flowing through the lungs increase.
- Blood to LA increase
- LA pressure increase than the RA
- Foramen closes
Neonatal circulation
Regurgitation of Mitral and tricuspid valves causes…… murmurs
Systolic murmurs
Neonatal circulation
Stenosis of mitral and tricuspid valves causes….. murmurs
Diastolic Murmurs
Neonatal circulation
Regurgitation of aortic and pulmonary valves causes……. Murmurs
Diastolic Murmurs
Neonatal circulation
Stenosis of Aortic and pulmonary valves causes…… murmurs
Systolic murmurs
Rheumatic fever
Age group
5-15
Rheumatic fever
MO causing Rheumatic fever
Group A beta- hemolytic streptococcus
Rheumatic fever
Pathophysiology of Rheumatic fever
Abnormal immune response to a preceding infection with group A beta- hemolytic streptococcus
Rheumatic fever
Rheumatic fever diagnostic criteria
Modified Duckett- Jones criteria
Rheumatic fever
Major criteria
- Migratory polyartheritis
- Carditis
- Sydenham chorea
- Erythema marginatum
- Subcutaneous nodules
Rheumatic fever
Minor criteria
- Fever
- Polyarthralgia
- Raised ESR, CRP
- Prolonged P-R interval
- History of Rheumatic fever
Rheumatic fever
Dx of Rheumatic fever
- 2 major OR
- 1 major + 2 minor
+ - supportive evidence of preceding Group A streptococcal infection
Rheumatic fever
Supportive evidence of preceding Strep infection
- markedly rasied ASOT
- Strep Antibodies
- Group A strep throst swab culture
Rheumatic fever
Joints involved in migratory polyarthritis
Large joints such as
* ankles
* Knees
* wrists
Rheumatic fever
Features of migratory polyarthritis
- Tenderness
- Moderate redness and swelling
Rheumatic fever
How long does the arthritis last in one joint and when does it migrate
<1 week in one joint and migrate over 1-2 months
Rheumatic fever
Pancarditis involves
- Endocarditis
- Myocarditis
- Pericarditis
Rheumatic fever
Mumur in endocarditis
Mid- diastolic murmur ( Carey Coomb murmur due to swelling of mitral valve)
Rheumatic fever
Valvular dysfunction is due to
endocarditis
Rheumatic fever
Myocarditis leads to
- Heart failure and death
Rheumatic fever
Pericarditis involves
- Pericardial friction rub
- Effusion
- Tamponade
Rheumatic fever
Late manifestation in Rheumatic fever
Sydenham chorea
Rheumatic fever
Sydenham chorea occurs after
2-6 months after the strep infection
Rheumatic fever
Sydenham chorea consists of
- Involuntary movements
- Emotional lability
- lasts 3-6 months
Rheumatic fever
Erythema marginatum is common. (T/F?)
False
Rheumatic fever
Erythema marginatum is seen on
Trunk and limbs
Rheumatic fever
Describe the appearance of erythema marginatum
Pink macules spread outwards, causing pink border with fading centre. Borders may unite to give a map-like outline
Rheumatic fever
Subcutaneous nodules are seen mainly on
Extensor surfaces
Rheumatic fever
Subcutaneous nodules appearance
Painless, pea-sized, hard
Rheumatic fever
Rheumatic fever occurs 2 weeks after a
pharyngeal infection
Rheumatic fever
All Rheumatic fever patients have a positive ASOT (T/F?)
F (only 80-85%)
Rheumatic fever
Chronic Rheumatic fever mainly affects
Mitral stenosis (scarring and fibrosis)
Rheumatic fever
The least common valve affected in Rheumatic fever
Pulmonary valve
Rheumatic fever
Mx of an acute Rheumatic fever episode
- Admit
- Bed rest
- Aspirin
- Steroids - if carditis or heart failure
- Stop steroids- if only arthralgia
- ABx (Oral penicillin or IM Benzathine penicillin)
Rheumatic fever
Usage of aspirin
NSAID. stop inflammation of the joints and the heart
Rheumatic fever
Anti- streptococcal ABx dose
- Oral penicillin 10 days
OR - IM benzathine penicillin single dose
Rheumatic fever
When will the anti streptococcal ABx be given
if there’s any evidence of persisting infections
Rheumatic fever
Most effective prophylaxis
2 weekly injections of benzathine penicillin or oral penicillin
Rheumatic fever
Issue with oral penicillin prophylaxis
poor compliance
Rheumatic fever
substitute to penicillin allergic patients
oral erythromycin
Rheumatic fever
Length of prophylaxis of only Rheumatic fever
for 5 years or until 21 years of age ( whichever is longer)
Rheumatic fever
Length of prophylaxis of Rheumatic fever + cardits
for 10 years or until 25 years of age ( whichever is longer)
Rheumatic fever
Length of prophylaxis of Rheumatic fever with residual heart disease
for 10 years or until 40 years of age ( whichever is longer) or even lifelong
Rheumatic fever
Complication of Rheumatic fever
chronic valve disease therefore getting infective endocarditis
infective endocarditis
infective endocarditis
inflammation of the endocardium due to alpha- hemolytic streptococcus
infective endocarditis
MO
Streptococcus viridans
infective endocarditis
Risk factors
- congenital heart disease (except ostium secundum ASD)
- Patients with prosthetic valves
infective endocarditis
Diagnostic criteria
Modified duke criteria
infective endocarditis
Major criteria of duke criteria
- 2 positive blood culture with typical organisms, 2 or more for less typical organism
- Evidence of endocarditis on echo - vegetations on a valve or another site, regurgitation near a prosthesis or abscess
infective endocarditis
Minor criteria of duke criteria
- Predisposing conditions- Rheumatic heart disease
- fever
- Emboli- vascular signs
- Immune complex phenomena ( Glomerulonephritis, arthrits, Rheumatoid factor, osler nodes, roth spots, janeway lesions)
- Single positive blood culture/ serological evidence of infections/ echo signs not meeting the major criteria
- Newly diagnosed clubbing/ splenomegaly
- Splinter hemorrhages, petechiae
- High ESR, CRP
- Non feeding lines or peripheral lines
- Microscopic hematuria
infective endocarditis
Dx of infective endocarditis
2 major criteria/ 1 major+ 3 minor/ 5 minor
infective endocarditis
Ix of infective endocarditis
- Blood culture- before ABx
- Echo
- ESR, CRP
infective endocarditis
Mx of infective endocarditis
IV ABx for 4-6 weeks ( penicillin + gentamicin)
infective endocarditis
Main prophylactic step
Good dental hygiene
infective endocarditis
ABx prophylaxis is given on
- dental treatment
- surgery
Child with fever and new- onset murmur
Infective endocarditis
infective endocarditis
complications
- Heart failure ( If aortic/ mitral V is involved)
- Myocardial abscess
- Myocarditis
- Life- threatening arrythmia
- systemic emboli ( with CNS Sx)
- Pulmonary emboli ( With VSD, TOF)
infective endocarditis
ADRS of gentamicin
nephrotoxic
Ototoxic
Cyanotic Heart disease
ToF consists of
- Overriding aorta
- Pulmonary stenosis
- Large VSD
- RV hypertrophy
Tetralogy of Fallot
Overriding aorta?
Aorta starts from both RV and LV chambers
Most common cyanotic congenital HD
Tetralogy of Fallot
Tetralogy of Fallot
Pathophysiology
- Aorta starts from both RV and LV
- This causes the pulmonary artery to stenose due to lack of space
- Pulmonary stenosis cause RV outflow obstruction.
4.RV outflow obstruction causes RV hypertrophy