AAAAA
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The main cause of
1. paradoxical splitting of S 2
2. The persistent splitting of S 2
3. The fixed splitting of S 2
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| powerranger
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for paradoxical split it is for aortic stenosis
for fixed splitting it is for pulmonic stenosis,and ASD
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| AAAAA
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The most common
1. LBBB
2. RBBB
3. ASD
The above are the most common causes (your answer is correct too !
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| powerranger
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thanks,
in Quick,how to diagnose RBBB,LBBB????
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| AAAAA
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First of all, there is a physiological split of 40-60 msec in AP to become A2------P2
This A2------P2 occurs in the inspiration when there is increased venous return and the pumonary valve delays closing. Valvular heart sound is caused by the closing.
(Just like you close the door, you shut the door and the door hit the frame and make a noise)
So the delay in closing of the pulmonary valve due to pressure built up in the venous return in the inspiratory phase will delay and causes physiological splitting.
But in LBBB, there is also a simultaneous aortic valve delay. So both doors are delayed and therefore there is a paradoxical splitting in which pulmonary valve DOOR closes first and then the aortic valve DOOR closes later. When a DOOR closes, it makes a noise. The doctors call this noise S2 !!!
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| AAAAA
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It is very simple to understand, you snap your palm/hand, it makes a noise.
Same as aortic and pulmonary door swing close and make a noise, the delay in swinging close of pumonary door is due to more people going to the pulmonary artery route. So the pulmonary door has to delay to accomodate more people so it closes 40-60 msec than the aortic door.
Also the aortic door is stronger to push all the people through the DOOR and closes !!!
It is just an example so you can understand !
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| AAAAA
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Left Bundle Branch Block (LBBB)-KH
LBBB is recognized by 1) QRS duration >0.12s; 2) monophasic R waves in I and V6; and 3) terminal QRS forces oriented leftwards and posterior. The ST-T waves should be oriented opposite to the terminal QRS forces.
Attached Files:
ecg_12lead013.gif (78 KB, 15 downloads)
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| AAAAA
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RBBB With Primary ST-T Wave Abnormalities-KH
RBBB is recognized by 1) rR' in V1; 2) QRS duration >0.12s; 3) terminal QRS forces oriented rightwards and anterior. In RBBB the ST-T waves should be oriented opposite to the terminal QRS forces. In this example there are "primary ST-T wave abnormalities" in leads I, II, aVL, V5, V6. In these leads the ST-T orientation is in the same direction as the terminal QRS forces.
Attached Files:
ecg_12lead014.gif (85 KB, 11 downloads)
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| AAAAA
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LBBB is best seen in leads I and/or V6, where there is M pattern. LBBB always means heart disease and prevents further interpretation of the ECG.
Left bundle branch block produces a deep S wave in lead V1 and a tall late R wave in leads I and/or V6.
Left bundle branch block is almost always caused by disease of the left ventricle and causes include:
Coronary artery disease: acute MI, severe two- to three-vessel disease
Cardiomyopathy
Hypertension
Aortic stenosis
Conduction system fibrosis.
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| AAAAA
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LBBB
Attached Files:
LBBB-ECG.jpg (58 KB, 8 downloads)
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| AAAAA
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LBBB graphic :
Attached Files:
LBBB-Heart-graphic.gif (25 KB, 7 downloads)
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| AAAAA
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LBBB latest graphic
Attached Files:
ECG%20-%20LBBB.jpg (22 KB, 8 downloads)
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