• Primary PCI for myocardial infarction is usually a relatively easy procedure
• The plaque is usually very soft making passage of wire easy
• Sometimes the pre-existing plaque may be already calcified
• This with the presence of plaque upstream may make wire crossing a bit challenging
• If the plaque is hardened, a good supporting guide is useful
• Amplatz shaped guides provide good support
• However, due to its shape, while on one hand provides good support, on the other makes it easier to create dissection at the ostium
• The following patient presented with acute inferior ST-Elevation Myocardial Infarction
• The attending doctor started with an Ikari Left 3.5 guide from the radial artery

Baseline angiogram

• This baseline angiogram shows a complete occlusion at mid RCA
• The operator started with a 6F IL 3.5 guide from the right radial

1 inf stemi

• After trying for some time with a soft wire, he was unable to cross the lesion
• He decided to change to stiffer wire
• However, he was still not able to cross the lesion.
• Thinking that he needed a more supportive guide, he decided to change to an AL 1

2 cant cross

• Unfortunately, he caused dissection of the RCA ostium

3 change guide

• Finding that he could not rewire the RCA with the AL1 guide, he changed to JR4 guide
• In his panic, he wired into the subintimal space rather than the true lumen

4 diff wire

• Thinking that he has wired the true lumen, he decided to stent the RCA ostium
• In his haste, he has not realised that the wire is actually sitting in the false lumen

5 is this correct

• After deployment of the stent, the RCA is now completely occluded
• He decided that since patient is not complaining of chest pain, he would abandon the procedure

6 subint stnt

Discussion

• Some acute coronary syndrome occur on the background of pre-existing subtotal occlusion
• Wiring these lesions in the presence of fresh thrombus may sometimes be challenging
• I find that the use of a tapered tip wire such as XT-R is very useful
• The chances of finding a track is higher than normal work horse ‘soft’ wire
• Sometimes the use of good supporting catheter is necessary
• In this case, extreme care should have been taken when using the Amplatz type guide
• The operator should also be careful when the wire is sitting
• Unfortunately the wire was in the sub-intimal space when the stent is deployed
• Long term wise, if the myocardium is not damaged, there may a chance of re-opening this lesion via the retrograde path