A Doubt on Sgarbosa Criteria

We know that the Scarbosa Criteria is used to detect AWMI in presence of pre existing LBBB.

Scarbosa Criteria
* 1mm or greater J point elevation in lateral leads v5,v6. (5points)
*1mm or greater J point depression in leads  v1,v2,v3. (3 points)
*5mm or greater J point elevation in leads v1,v2,v3 (2 points)

Im considering the third point here for discussion.

Back ground: LBBB is always associated with secondary ST segmant and T wave changes. (Discordant changes)
MI is associated with primary ST segment and T wave changes. (Concordant changes)


So here, in third point of sgarbosa criteria, the J point elevation of 5mm or above is in discordance with QRS complex, which is contrary to the definition of ST-T changes in acute MI. Though there is an elevation of J point, the changes are not in concordance with QRS complex.

Therefore, in my view, points 1 and 2 of Scarbosa criteria are only relevant with the definition of repolarization changes in MI.
But we see patients, who are satisfying only 3rd point of Scagbosa criteria were having RWMA by 2d echo and according to Scarbosa criteria this carries score of 2, but a score of 3 or more only diagnostic to MI.

In my opinion, such cases which are satisfying only 3rd point of Scarbosa criteria could be a case of NSTEMI, with RWMA and elevated enzymes.

Conclusion: 1st and 2nd points of Scarbosa criteria are to diagnose AWMI, in presence of LBBB,  and third point to diagnose NSTEMI.

Intrinsicoid Deflection

In BBB and  LVH we see prolongation of intrinsicoid deflection on ECG. But many times this deflection is defectively calculated in leads like v1, v2,v3 etc.


the reality is INTRINSICOID deflection should be measured only in LATERAL LEADS v5,v6, I, and Avl.

why?.

intrinsic deflection is the time taken for the depolarization wave to spread from endocardium to epicardium when the lead is placed directly on the heart. But on surface ECG these leads are placed on chest wall far away from the myocardium. Hence the deflection is called intrinsicoid (=intrinsic like) deflection.

As the lateral leads look the electrical activity of the heart from a vantage point and are least influenced by the elctrical forces from the other parts of the heart, these are the ideal leads to measure the intrinsicoid deflection.

usually it takes 45msec to reach the electrical activity from endocardium to epicardium. duration more than thius is considered as prolonged intrinsicoid deflection.

Left Bundle Branch Block (LBBB)- understanding and solving the problem of MI.

Many times we confuse to confirm the presence of LBBB. Here are certain tips.


Back ground :1. Usually a big wave is created when depolarization spreads in left ventricle and small wave is created when it spreads through the right ventricle. Positive wave is created when depolarization spreads towards the lead and negative wave is created when depolarization spread away from the lead. First part of the QRS complex indicates depolarization of LV and second part of QRS complex denotes depolarization of RV.
               2. In BBB the QRS complex has two parts: the first part and second part. Each part formed by each ventricle.



What happens in LBBB is left ventricle depolarizes after depolarization of right ventricle. Which is unusual.(remember the sequence RV -->LV),

       Hence, first part of QRS complex denotes RV and second part denotes LV.
But lateral leads v5, v6, I, avl cannot catch depolarization of RV. So they do not have q waves. V1 to v4 may have initial small, positive 'r' wave as the depolarization speads via RV and towards the leads( RV is located anterior to the LV).
inferior leads II, III, Avf has different story, as the inferior part of heart is formed by LV. Initial small positive 'r' wave (actually negative with reference to an inferiorly located lead) is from RV.

The second part of QRS complex is formed by LV. As the conduction is delayed in the LV, the duration of deploarization wave is longer than that of RV, so that overall QRS duration is prolonged. The lateral leads v5, v6, I, Avl have only broad positive QRS wave as they do not recognize the depolarization of RV. So these are the only leads that recognize the depolarization of only LV. These are ONLY LV  leads. Thats why, the QRS complex is monophasic in these leads. As these are the ONLY LV leads, the bigenning of R wave to the peak of R wave denotes the spread of depolarization from endocardium to epicardium in these leads, which is called 'intrinsicoid deflection' which is prolonged due to delay of conduction. (Intrinsicoid deflection should be calculated in these ONLY LV leads).
In v1 to v4 leads the depolarization wave spreads posteriorly(away from the leads) as the posterior part is formed by LV. So they have a deep broad negative wave. The inferior leads also have a deep, broad negative wave Which is actually a positive wave with reference to the inferior leads. So that anterior and inferior leads will have a deep, broad S wave.
A positive R wave in I, and a negative S wave in AVF causes left axis deviation. (Heart is not rotated, only the axis of depolarization is towards the left).

To summerize. Broad QRS complex >120msec and left axis deviation PLUS
                             1. Absent q waves in lateral leads.
                             2. Monophasic QRS complex in lateral leads.
                             3. Prolonged intrinsicoid deflection in lateral leads.
                             4. rS waves in anterior leads.
                             5. rS waves in inferior leads.

But story not ends here with depolarization. There is also a part of repolarization. Usually repolarization wave of right ventricle is not catched by the leads. Whatever repolarization changes we see on ECG  are from LV. There are changes in the ST segment and T waves. But these changes are not due to defective repolarization, but are secondary to abnormal depolarization. Hence these are secondary replarization abnormalities. These ST T changes are discordant (opposite in direction) with the QRS deflection.
 Greater the depolarization changes greater the ST T repolarization changes. Deeper the S wave in the V1, higher the ST T changes in V1. Taller the R wave in V6, greater the ST T depression in V6. This creates confusion in diagnosing AWMI in presence of LBBB.
             In general positive R wave with positive J point elevation is specific for MI.
In LBBB, 1.positive R waves are seen in lateral leads. If these leads show a concordant J point elevation of atleast 1mm, then it is more specific for MI  carrying 5 points.
                 Except lateral leads no other leads have a positive QRS complex in LBBB. There fore, 2. At least 1mm of J point depression in v1 to v4 concordance with QRS changes carries 3 points
     Anterior lead's discordant ST T  changes depend upon the depth of S wave. There fore  3. >5mm J point elevation is needed to diagnose in these leads, and it carries only 2 points. Hence this 3rd point is though more sensitive, it is less specific.
 That mean, when only this is the only finding on ECG, the chances of MI  are less likely.
These three constitute SGARBOSA criteria to diagnose MI in presence of LBBB. Presence of a score of >3 is diagnostic.

chordal SAM.

This is a rare case of HCM with obstruction, but not due to SAM of AML  but due to SAM of chordae. The chordae here are very slacking so that they are in direct relation with the flow towards the LVOT. This is another evidence for us that the guiding forces of SAM in classical HOCM are not due to Venturi effect but due to flow drag forces.
This patient presented with atypical chest pain.

In this video there is an asymmetric septal hypertrophy, and there is a diastolic anterior motion
There is a moderate MR( not shown).

This combination of systolic anterior motion of chordae and diastolic anterior motion of AML is very rare.

The Goal- Primary vs Secondary

When man identified the existence of a greater world beyond his imaginations, he slipped all his thoughts into an existence of a being acting behind, which he named most of the times a Supreme Power, the God. And hence the spirituality started its work to find Him. The Allies of it, the science called this power a driving force or unifying principle and philosophy called its the Truth. However, when the goal of spirituality is set as finding that Supreme Power, at Individual level where the man lives in many complexities of life, it becomes very very difficult so much so that almost a rarity, as if a sinking man in an ocean finds a small wooden plank to rescue himself. But man became comfortable with the idea of God, as he got releaved to some extent, from the intricacies of life. To go further, he has no other option except to stick to the belief of God's existence and hence the perpetuation of this idea of spirituality.

angels

Human beings have developed lot of vision except a blind spot in his perception when it comes to the matters of belief. Now a days these rae not at all beliefs. These are fantasies, not in lesser degree than any hollywood action movies. These blidspots in our perceptions are called confirmation biases.Jerry Hall once said " I love mysticism, its such a fun". I think you are writing jokes here in posts.And, mysticism and exaggeration always go together. And in what way these semi lucid, crazy ideas will help the humanity and its problems? .Thank you,Namasthe.