Cardiology Flashcards
An incidental finding of left bundle branch block requires further investigation - true or false?
False. No further investigation is required based upon ECG alone.
Heart rate is normally controlled by?
SA node.
If unable to determine if a broad QRS is of ventricular origin, how would you proceed?
Treat it as ventricular tachycardia.
- VT should be always be confirmed by 12 lead ECG if patient is not in cardiac arrest.
What causes aberrant conduction?
When length of cardiac cycle changes without compensatory change in length of the refractory period.
What is aberrant conduction?
Abnormal conduction of the supraventricular impulse to the ventricles.
Capture and fusion beats are almost always diagnostic of what and why?
Ventricular tachycardia - they are proof of independent rhythms in the atria and ventricles.
What is a capture beat?
Sinus node “captures” the ventricles to produce a narrow-complex beat.
(In the midst of AV dissociation, an atrial impulse arrives at the AV node when the node has just recovered from its refractory period. -
- Produces a QRS of normal duration.)
What is a fusion beat?
A sinus and ventricular beat coincide, fusing to form a complex of intermediate morphology.
The Bundle of His separates into which two bundle branches?
Left and right.
When should someone with left bundle branch block be thrombolysed?
If they are symptomatic of MI (also consider Cath lab as alternative to thrombolysis).
Left bundle branch block is best seen in which lead?
V6.
ECG findings suggestive of LBBB?
- W shaped QRS in V1.
- M shaped QRS in I, aVL, V5, V6.
- QRS >0.12s.
- Small R wave in V2, V3 (due to activation of paraseptal region)
Causes of left bundle branch block?
Heart disease e.g. IHD, MI, cardiomyopathy, hypertension.
Delta wave in V1 suggests which underlying pathology?
Wolff-Parkinson-White syndrome (type A).
(Type A - positive R wave in V1 as the accessory pathway is a left atrioventricular connection. - Type B - negative R wave in V1 as the accessory pathway causes a negative R wave in V1).
Wolff-Parkinson-White syndrome can cause which arrhythmia?
Supraventricular tachycardia.
What is the cause of Wolff-Parkinson-White syndrome?
Congenital accessory conduction pathway connecting atria and ventricles.
Why can high atrial rates be conducted to the ventricles in Wolff-Parkinson-White syndrome?
The accessory conduction pathway lacks the rate-lowering properties of the atrioventricular node.
Definitive management of Wolff-Parkinson-White syndrome?
Radiofrequency ablation - destruction of the abnormal electrical pathway.
Causes of mitral stenosis?
CRAP - Congenital. - Rheumatic. AND - Prosthetic valve.
Signs of mitral stenosis?
- Malar flush.
- Atrial fibrillation, palpitations, thromboembolism, embolism.
- Left or right heart failure.
- Tapping, undisplaced apex beat.
- Loud S1 with an opening snap and a rumbling mid-diastolic murmur.
- Cachexia, cyanosis, COPD, bronchiectasis.
- Haemoptysis, rupture of congested bronchioles, hoarse voice (LA enlargement).
- Syncope.
Name the murmur. Loud S1 with an opening snap and a rumbling mid-diastolic murmur heard best with the patient on their left side and in expiration.
A Graham Steell murmur can occasionally be found.
Mitral stenosis.
Pulmonary stenosis is what type of murmur?
Ejection systolic.
Ventricular septal defect causes what type of murmur?
Pan-systolic murmur.
Mitral valve prolapse causes what type of murmur?
Mid-systolic click, followed by a late systolic murmur.
Right bundle branch block causes what type of murmur?
Wide splitting of the second heart sound.
Myocardial infarction symptoms?
CUBE
- Central crushing chest pain >20min, radiating to left arm or jaw.
- Upset stomach with nausea and vomiting.
- Breathlessness.
- Excessive sweating.
Most likely cause of a Q wave myocardial infarction (i.e. elevated ST segments in consecutive leads and Q waves on ECG)?
Completely occlusive thrombus.
- ACS typically due to rupture of a vulnerable plaque
Elevated JVP with large V-waves and a pan-systolic murmur at the left sternal edge?
Tricuspid regurgitation
Features of tricuspid regurgitation?
- Elevated JVP with large V-waves.
- Pan-systolic murmur at left sternal edge.
- Pulsatile hepatomegaly.
- Left parasternal heave.
Ejection systolic murmur that radiates to the neck.
Aortic stenosis.
Pan-systolic murmurs?
- Tricuspid regurgitation (left sternal edge).
- Mitral regurgitation (apex > axilla).
Pan-systolic murmur at apex radiating to the axilla.
Mitral regurgitation.
Mid-diastolic murmur heard best at left sternal border.
Tricuspid stenosis.
Ejection systolic murmur in the 2nd left intercostal space.
Pulmonary stenosis.
Mid-diastolic murmur at the apex.
Mitral stenosis.
Severe mitral stenosis may cause secondary pulmonary hypertension and therefore lead to which murmur?
Tricuspid regurgitation.
Turner syndrome is associated with which cardiac defect?
- Coarctation of the aorta.
- Aortic stenosis.
- Bicuspid aortic valve.
- Aortic dilatation and dissection.
Marfan syndrome is associated with which cardiac defect?
- Aortic root dilatation > aortic regurgitation.
- Mitral valve prolapse.
- Mitral regurgitation.
- Risk of aortic dissection.
Kartagener syndrome is associated with which cardiac defect?
- Dextrocardia.
bronchiectasis + infertility
Congenital rubella syndrome is associated with which cardiac defect?
- Patent ductus arteriosus.
- Atrial septal defect.
- Pulmonary stenosis.
Post Myocardial infarction, patients should refrain from sexual intercourse for how long?
4 weeks.
Post Myocardial infarction, patients should refrain from driving a bus/ lorry for how long?
6 weeks.
Car - one week if successful angioplasty or four weeks if not.
Post Myocardial infarction, patients should refrain from operating heavy machinery for how long?
4 weeks.
Post Myocardial infarction, patients should refrain from vigorous exercise for how long?
4 weeks.
