Cardiology Flashcards
Causes of Prolonged PR interval
SLIM HAAIRD
Causes of a prolonged PR interval
Sarcoidosis
Lyme disease
Idiopathic
myotonic dystrophy
hypokalaemia*
aortic root pathology e.g. abscess secondary to endocarditis
athletes
ischaemic heart disease
rheumatic fever
digoxin toxicity
A prolonged PR interval may also be seen in athletes
A short PR interval is seen in Wolff-Parkinson-White syndrome
*hyperkalaemia can rarely cause a prolonged PR interval, but this is a much less common association than hypokalaemia
Abnnormal P waves. What causes:
1) P-pulmonale
2) P-mitrale
Think is the P wave too tall (>2.5mm) or is the P wave too wide ( 2 small boxes), then consider strial chamber enlargment.
1) P-pulmonale: Pulmonary disease (Cor-pulmonale). pulmonary valve stenosis
2) P-mitrale: mitral stenosis
If an atrium becomes enlarged (typically as a compensatory mechanism) its contribution to the p wave will be enhanced. Typically changes are in lead II and VI.
P-pulmonale, so called because pulmonary disease is the most common cause, where enlargement of the right ventricle is due to increased resistance of blood emptying into the right ventricle. This may be due to pulmonary valve stenosis, increased pulmonary pressure etc. The right atrium must then enlarge (hypertrophy) in order to pump blood into the right ventricle. Right atrial enlargement (hypertrophy) leads to stronger electrical currents and thus enhancement of the contribution of the right atrium to the P wave.
P-Mitrale, so called because mitral valve disease is the most common cause. If the left atrium encounters increased resistance (eg due to mitral valve stenosis) it becomes enlarged (hypertrophy) which amplifies it’s contribution to the P wave. The second hump in lead II becomes larger and the negative deflection in V1 becomes deeper.
the normal cross sectional area of the mitral valve is 4-6 sq cm. A ‘tight’ mitral stenosis implies a …..
cross sectional area of < 1 sq cm
Features of severe mitral stenosis
1) length of murmur increases
2) opening snap becomes closer to S2
What happens to the opening snap of mitral stenosis when the vakve is heavily calcified?
Openiong snap is characteristically lost with heavy valvular calcification
An opening snap suggests that the mitral valve is mobile. It is not heard when the valve is heavily calcified
For degenerative nitral regurgitation what surgical treatment is preferred- valve repair of valve replacment?
Valve repair
The evidence for repair over replacement is strong in degenerative regurgitation, and is demonstrated through lower mortality and higher survival rates
When this is not possible, valve replacement with either an artificial valve or a pig valve is considered
Features of more severe mitral regurgitation
Apex beat displacement
Systolic thrill
Mitral Valve prolapse is usually idiopathic. However it may have certain associations…
TWO FLAME PPPC
Turner’s syndrome
Wolff-Parkinson White syndrome
osteogenesis imperfecta
Fragile X
long-QT syndrome
ASD
Marfan’s syndrome
Ehlers-Danlos Syndrome
pseudoxanthoma elasticum
polycystic kidney disease
PDA
cardiomyopathy
S2 is caused by closure of the pulmonic and aortic valves. What causes wide splitting?
deep inspiration
RBBB
pulmonary stenosis
severe mitral regurgitation
S2 is caused by closure of the pulmonic and aortic valves. What are 5 causes of paradoxical splitting?
Causes of a reversed (paradoxical) split S2 (P2 occurs before A2)
LBBB
severe aortic stenosis
right ventricular pacing
WPW type B (causes early P2)
patent ductus arteriosus
Causes of fixed split S2
atrial septal defect
Atrial septal defect effect on heart sounds
fixed split S2
Causes of a soft S2
aortic stenosis
3 Causes of a loud S2
Causes of a loud S2
hypertension: systemic (loud A2) or pulmonary (loud P2)
hyperdynamic states
atrial septal defect without pulmonary hypertension
S3 heart sound is due to rapid ventricular filling during diastole. Give 4 causes?
- considered normal if < 30 years old (may persist in women up to 50 years old)
- left ventricular failure (e.g. dilated cardiomyopathy),
- constrictive pericarditis (called a pericardial knock)
- mitral regurgitation
S4 is caused by atrial contraction against a stiff (hypertrophied) left ventricle. Give Causes?
S4 (fourth heart sound)
may be heard in 1) aortic stenosis, 2)HOCM, 3) hypertension
caused by atrial contraction against a stiff ventricle
therefore coincides with the P wave on ECG
in HOCM a double apical impulse may be felt as a result of a palpable S4
describe murmurs and heart sounds of mitral valve murmurs
1) Mitral regurgitation
2) Mitral valve prolapse
3) Mitral stenosis
1) MR- blowing pansystolic murmur at the apex, radiating to axilla. +/- quite S1 (due to incomplete valve closure) and in severe cases wide splitting of S2
2) Mitral Valve prolapse- mid-systolic click (occurs later if pt squatting) + late systolic murmur (longer if pt standing
3) MS- mid to late diastolic murmur. loud S1, opening snap

describe murmurs and heart sounds of aortic valve murmurs
1) Aortic Stenosis
2) HOCM
3) Coarctation of the aorta
4) Aortic regurgitation
1) AS: Ejectio systolic murmur, radiating to the carotids. loud S4 (from stiff or hypertrophic left venrticle)
2) HOCM: Ejection systolic murmur, increased with valsalva manouveur and reduced by squatting
3) Coarctation of the aorta: Mid-systolic murmur, maximal over the back
4) AR: Early distaolic murmur increased by handgroup manouveur