- The septal channels are the best conduit to utilize for retrograde approach
- Very often we use it to cross from LAD to PDA and vice versa
- There are times when I have used it to cross from LAD to a dominant LCx
- This case shows a septal channel coming from mid LAD connecting to distal LAD
Baseline angiogram
- This angiogram shows the CTO starting after the 2nd large septal
- The distal entrance is small calibre
RAO cranial view of baseline
- This view shows the septal collateral coming off the 2nd septal and joining the distal LAD
The initial antegrade approach
- The initial approach was naturally antegrade as there appeared to be possible micro-channel
- 135mm Corsair was utilised with Fielder Black wire
- After a few repeated attempts, the wire remained in the sub-intimal space
Change of strategy was required
- Deep injection into the Corsair was made to look for the septal collateral
- It also shows that false lumen has been created and the antegrade micro-channel compressed
The Corsair entered the septal collateral
- The septal collateral can be seen re-entering the distal LAD
Channel crossing
- XT-R was used to gently cross the channel
Crossing completed
- The XT-R re-entered the distal LAD and parked in a distal diagonal
Antegrade landmark
- A Runthrough was parked in the proximal cap as landmark for retrograde crossing
Attempting to meet up
- Although a Gaia 2nd was used, it was unable to penetrate the proximal cap
However, a Conquest Pro 12 (Confianza) was able to enter the proximal LAD
- Since the Corsair used was only 135mm, it was not long enough to enter the guiding catheter
- It was maneuvered across passed the CTO segment into the mid LAD and Conquest Pro changed out to RG3
- The RG3 was then carefully driven into the guider and externalised

- After initial pre-dilatation with 2.0 balloon, a Runthrough was passed down anterogradely and the retrograde system removed.
- The LAD was stented in distal to proximal fashion
Final angiogram
- This showed the adequately treated LAD
- The septal channel is also more clearly seen