Left and right BBB
signs and symptoms of BBB?
- usually asymptomatic - may complain of syncope (due to intermittent complete heart block/ventricular tachyarrhythmia)
which BBB is always pathological?
left
what may you hear on auscultation of a patient with LBBB?
reverse splitting of the 2nd heart sound
what shape is seen in the V1/V6 leads of someone with RBBB?
- 'M' in V1 - 'W' in V6 - opposite of LBBB
what shape is seen in the V1/V6 leads of someone with LBBB?
- 'W' in V1 - 'M' in V6
what causes RBBB?
- isolated congenital anomaly - or cardiac/pulmonary conditions
what happens in LBBB?
1. left bundle branches defect prevents/slows flow of conduction 2. activation of the LV is delayed 3. LV contracts later than the RV
what is seen on an ECG of someone with BBB?
= WIDENED QRS complex (>0.12s). different shape depending on L or R
define bundle branch block
a defect of the bundle branches/fascicles in the electrical conduction system
what happens in RBBB?
activation of the RV is delayed
what causes LBBB?
extensive left ventricular disease e.g. aortic stenosis, HTN
what may you hear on auscultation of a patient with RBBB?
splitting of the 2nd heart sound
