We Always Need Good Support 

A 45 years old gentleman, with a history of hypertension and obesity, who was also a chronic smoker. He complained of exertional compressive chest discomfort for few months and his symptoms had worsened for few weeks. ECG did not show any acute ischemic changes. Cardiac enzymes were normal. Echocardiogram showed normal biventricular function without valvular lesions or regional wall motion abnormalities. Coronary angiogram showed critical proximal LAD/1st Diagonal (1.1.1) bifurcation lesion (Movie 1, Movie 2). Left main, left circumflex and right coronary artery were unremarkable.

PCI was proceeded with VL 3.5 guiding catheter via radial approach. Both Diagonal and LAD were wired with Sion and predilated. A DES of size 3.5x23mm (Movie 3) was implanted and post dilated with non-compliant 4.0 balloon. But on retrieval of the balloon, due to poor guiding catheter support, both the wires were lost. VL 4.0 guiding catheter was then used for better support. LAD was wired through the deployed stent but subsequently balloon could not be advanced. After few attempts, the balloon could eventually be advanced into the stent but was not able to go more distally. OCT was used to assess the position of the wire but it could not be advanced into the stent. The wire was likely under the stent struts. Repeated device advancement made the proximal stent more deformed and was crushed into a metal mesh (Movie 4). A microcatheter could be advanced into the distal LAD to exchange for a more supportive guidewire. But upon retrieval of the microcatheter, the coronary wire was accidentally withdrawn as well. Repeated angiogram showed the mid-LAD was occluded beyond the proximal stent. Luckily patient remained stable. The LAD was rewired but this time the microcatheter could not be advanced. By using a Fielder XT-A guidewire, it could be wired into the distal LAD and a more supportive guidewire was exchanged through the microcatheter. A 1.0mm balloon was able to cross the stent edge mesh and it was dilated distally. However, a 2.0mm balloon could only be advanced into the proximal stent and could not be advanced further. So the stent was dilated with the 2.0mm balloon. An IVUS was attempted to pass through the stent to assess the portion of LAD beyond the stent but was not successful. Then it was decided to switch to femoral approach using a VL 4.0 guiding catheter. The 2.0mm could eventually be advanced beyond the stent. Progressive balloon dilation was performed to crush the metal to the coronary wall. Another 4.0x12mm stent was deployed proximal LAD overlapping with the previous stent (Movie 5). However, on repeat contrast injection, there was extensive thrombus distal to the first stent despite optimal ACT measurement (Movie 6). It was managed by further balloon dilatation and stenting. The distal LAD was treated with drug coated balloon. But it was complicated with dissection and need further stenting with 2.5 x 33mm stent (Movie 7). Patient was stable during the procedure and was discharged without elevation of cardiac enzymes.

If the coronary vessel is not extremely calcified or tortuous, normally proximal lesions do not require guiding catheters with very good backup support. However, if the stent is not fully expanded after initial deployed, subsequent passage of post-dilation balloons will be difficult even for proximal lesions. The alignment of the vessel can also be changed after stenting, making passage of post-dilatation balloon difficult. Care must be taken not to forcefully advance balloon through the stent struts as it may destroy and deform the stent, making subsequent passage of devices difficult. Using buddy wire technique or using a more supportive coronary wire may help to pass the balloon down. Ancillary devices such as Guideliner or Guidezilla may provide more backup support especially if the radial approach is used. If the coronary wire is accidentally lost before the stent is fully expanded, the coronary vessel should be rewired with a knuckled tip to make sure the wire will not go under the stent strut. Unfortunately, if the coronary wire cannot be wired into the central lumen of the destroyed stent and the wire keeps going under the stent struts, the last resort is to crush the deformed stent against the coronary wall and to deploy a new stent over it. But the result will be suboptimal and there will be a chance of stent thrombosis.