Identifying infarction In LBBB and Ventricular Paced Rhythms

Question 1

Modified Sgarbossa criteria (MSC)

Answer 1

Found to have 91% sensitivity and 90% specificity for identifying STEMI in LBBB/paced rhythms.

Criteria:

• Concordant ST elevation > 1mm in leads with a positive QRS complex (Score 5)
• Concordance ST depression > 1mm in V1-V3
• Proportionally Excessive Discordant ST elevation in one or more Lead anywhere with 1 or more (1mm) of ST elevation, as defined by greater than/equal too 25% of the depth of the preceding S wave.

Question 2

Appropriate discordance ?

Answer 2

ST Segment and T wave are expected to move in opposite direction to the vector of the QRS complex .

If QRS positive - T wave negative (and vice versa)

Question 3

What is the first Modified Sgarbossa Criteria ?

Answer 3

Concordant ST elevation above (or equal too) 1mm in leads with a positive QRS complex.

Question 4

What is the second criteria for the Modified Sgarbossa Criteria?

Answer 4

Concordance ST depression above 1mm in V1-V3

Question 5

What is the Third criteria of the Modified Sgarbossa Criteria ?

Answer 5

Proportionally Excessive Discordant ST elevation

in 1 or more leads anywhere

With more than/equal too 1mm of ST elevation , as defined by more than or equal too, 25% the depth of the preceding S-wave.

Question 6

How many of these criteria classify someone as Sgarbossa positive?

Answer 6

1 or more.