1. 67 yom presents after syncope (while going to restroom)
67 yom presents after syncope (while going to restroom). Mild dyspnea, no CP, BP 110/70

2. ECG findings Final dx: PE with signs of RV/RA overload
Sinus tachycardia with frequent PACs
Right axis : net QRS is (-) in lead I; QRS is closest to equiphasic in lead aVF axis close to +180 degrees
RAE (by lead II and lead V1 criteria)
S>R in V6 + Right axis deviation RVH
S1Q3T3 c/w right axis (big S in lead I) and RVH
T inversion in V1-V3:
ddx: anterior ischemia vs RV strain
Final dx: PE with signs of RV/RA overload

3. How to assess QRS axis?
1st step:
Look in leads I and aVf,
and potentially in lead II if needed
2nd step
(not very important for residents):
See where QRS is closest to
isoelectric, the axis is 90 degrees
perpendicular to it in the
corresponding quadrant

5. RV enlargement leads to increased R wave height in the right-sided lead V1 and increased S wave in the left-sided lead V6