• Currently there are many PCI wires in the market
• However, the leader in CTO wires is still Asahi
• Boston Scientific has recently launched a few wires targeted at CTO
• However, there is not much accumulated experience so far
• The following case illustrates how different properties of wires comes into play when doing CTO
• This is a case of LAD CTO

There is good collateral from the RCA showing distal filling
It seems that the distal LAD has good run-off

The proximal cap seems to be just distal to the diagonal branch

The AP cranial view doesn’t demonstrate any lead in

Following the path of calcification, the path of LAD may be where the arrow is pointing to

This is the path a Runthrough insisted on taking. It will not progress further beyond this point neither will it turn towards where the LAD was thought to be

Injecting dye down the Corsair to see if we have missed anything

Injecting dye via the Corsair seems to show the same thing

Decided to use a soft slippery wire to enter the diagonal and then turn down
This is a PT2 wire from Boston
Without any effort, the wire slipped down, not in the planned path, but same path as the Runthrough without any resistance
As serendipity would have it, this is the LAD!

However, at this point, the PT 2 would progress no further
Deep injection down the Corsair shows that there seems to be another CTO point although the RCA angiogram did not pick up any occlusion from the collateral flow
At this point, the PT 2 was changed out to an XT-R

The XT-R made reasonably easy progress to this point
At this point, it will either enter the septal or diagonal
Even with Corsair support, it refuses to proceed straight down the LAD
This is because the whole wire is jacketed. The hydrophilic nature makes it goes towards path of least resistance
It will not catch the CTO cap

The deep injection again defers from that of the RCA collateral

In order to catch the proximal cap, a non-coated tip wire would be better
An Ultimat Bro 3 was chosen
It easily caught the proximal cap and crossed the CTO without much fuss
The UB3 was then changed back to the soft Runthrough and LAD ballooned

This is the final angiogram after successful stents deployment/span>

Conclusion

• There seems to be somewhat over zealous use of wires in this case
• In retrospect, one might have gotten away with just a single UB3
• However, we usually try to traverse micro-channels to stay within the true lumen
• For this purpose, a jacketed wire is best
• However, sometimes the channels are so microscopic that a tapered tip wire is needed which is when PT2 was changed to XT-R
• Unfortunately, the slippery tip does not make catching the proximal CTO cap easy especially when the cap is at a junction. In this case a ‘T’ junction, which made it doubly difficult
• A non-coated tip wire such as UB3 makes life easier
• The stiffer tip also means that the body won’t prolapse into the branches