akroeze Posted May 24, 2009 Posted May 24, 2009 Am I missing something here? I'm seeing 3rd AVB with ventricular escape.
celticcare Posted May 24, 2009 Posted May 24, 2009 Def CHB, and its a LBBB for the reason listed prior, negative in lead v1 and wide QRS complex. Looks like ST depression in Lead 2 also.
FL_Medic Posted May 24, 2009 Author Posted May 24, 2009 You are not getting off that easy. What do you see in all leads that says RBBB? QS or rS wave in v1 indicates LBBB. You also have an axis in between -30 & -60 degrees which is debatable pathological left axis deviation indicating anterior fasicular block, so you could debate at lease one of the left fasicles is blocked; unless you are calling it physiological left axis devation. Either way, its borderline if it is a BBB, the QRSd is slightly wide, but you have complete AV dissassosciation, abberency is expected.
ERDoc Posted May 24, 2009 Posted May 24, 2009 So, what I am seeing is a 3rd degree block with a LBBB. I think we all agree on the 3rd degree block so no need to go into further detail. In this case your ventricular rate is in the 40s which would indicate a focus in the junction. You would expect to see narrow complexes but we see wide complexes with makes you think of a BBB. We have identical monomorphic waves in I and v6 as well as a wide S wave in v1 which points to a LBBB. Although, one could argue that you have the 3rd degree block with an accelerated ventricular rhythm originating on the right. Either way, it is more of an academic arguement at that point as the treatment is going to be the same.
Mateo_1387 Posted May 24, 2009 Posted May 24, 2009 There is complete AV disassociation. This is why the QRS complexes widen with complete heart block. Wouldn't the QRS width be determined if the AV Node is blocked at the node, or just inferior to the node? For my interpretation, I am seeing... 3rd Degree heart block LBBB and LAFB. LBBB is seen with LAD, - deflection S wave in V1, and LAFB with the - deflections of II, III, and aVF.
Tom B. Posted May 24, 2009 Posted May 24, 2009 It is a LBBB, as the QRS is wide (its borderline at 0.12 sec), negative in V1 and the underlying rhythm is supraventricular in origin Just to play devil's advocate, how do you know the rhythm is supraventricular in origin? Tom B.
chbare Posted May 24, 2009 Posted May 24, 2009 Wouldn't the QRS width be determined if the AV Node is blocked at the node, or just inferior to the node? For my interpretation, I am seeing... 3rd Degree heart block LBBB and LAFB. LBBB is seen with LAD, - deflection S wave in V1, and LAFB with the - deflections of II, III, and aVF. Unfortunately, by definition you cannot have a left anterior fascicular hemiblock with a left bundle branch block. Remember, we have three fascicles. Two on the left and one on the right. A left bundle branch block can only occur when both fascicles on the left side fail, thus causing a true block of the left bundle branch. Just to clarify the terminology because it is confusing: 1) A hemiblock refers to the block of a single fascicle on the left side. 2) A bifascicular block refers to the block of the right and the block of one of the left fascicles. 3) A trifascicular block refers to the block of the right, block of one of the left fascicles, and an incomplete or possibly intermittent block of the last remaining fascicle. Take care, chbare.
Mateo_1387 Posted May 24, 2009 Posted May 24, 2009 Unfortunately, by definition you cannot have a left anterior fascicular hemiblock with a left bundle branch block. Remember, we have three fascicles. Two on the left and one on the right. A left bundle branch block can only occur when both fascicles on the left side fail, thus causing a true block of the left bundle branch. Just to clarify the terminology because it is confusing: 1) A hemiblock refers to the block of a single fascicle on the left side. 2) A bifascicular block refers to the block of the right and the block of one of the left fascicles. 3) A trifascicular block refers to the block of the right, block of one of the left fascicles, and an incomplete or possibly intermittent block of the last remaining fascicle. Take care, chbare. True That ! Thanks chbare for correcting me.
Tom B. Posted May 24, 2009 Posted May 24, 2009 I'm still curious to know how you differentiate between a junctional escape rhythm with LBBB and a ventricular escape rhythm. If wide complex rhythms are ventricular until proven otherwise, then you should consider this 3AVB with a ventricular escape rhythm. Or, 3AVB with a wide complex escape rhythm. There's no need to call it a BBB. Maybe it is, maybe it isn't. Tom B.
chbare Posted May 24, 2009 Posted May 24, 2009 I'm still curious to know how you differentiate between a junctional escape rhythm with LBBB and a ventricular escape rhythm. If wide complex rhythms are ventricular until proven otherwise, then you should consider this 3AVB with a ventricular escape rhythm. Or, 3AVB with a wide complex escape rhythm. There's no need to call it a BBB. Maybe it is, maybe it isn't. Tom B. As ERDoc stated, debating the specific focus of the escape rhythm is academic when considering the pre-hospital treatment of a symptomatic patient. However, for the sake of mental masturbation, why not discuss the possible focus of the escape rhythm? Again, I point to the axis. Right shoulder axis deviation is still suggestive of a ventricular rhythm; however, this patient clearly does not demonstrate right shoulder axis deviation. As people have stated, the right shoulder finding is not always the case; however, it still provides evidence against a ventricular rhythm. As ERDoc stated, the rate is around 40, this is ~the upper limit for a ventricular escape (not including accelerated rhythms), and the ~ lower limit for a junctional rhythm. So, yes I would agree, it's a hard call when you have a wide complex escape rhythm with a rate that could go either way. In my case, I am using the axis as a tie breaker. Take care, chbare.
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