During complex left branch bifurcation, utilizing a two-stent technique may be a fruitful, “simple approach” to treat certain subtypes of coronary bifurcation stenting, said Antonio Colombo, MD, of the Centro Cuore and San Raffaele Hospital in Milan, Italy, during a presentation at the fourth annual Left Main and Bifurcation Summit April 29 in Seoul, South Korea?, sponsored by the Cardiovascular Research Foundation.
“There are still these ideas that the two-stent technique may be more dangerous and something that operators should avoid--this statement is wrong,” said Colombo, as he reviewed standard treatment strategies used during left main bifurcation PCI.
While Colombo agreed with previous research that the T-stent strategy should be the “default treatment for most bifurcations,” he offered that there may be “some subtypes of coronary bifurcations that nonetheless merit a systematic two-stent strategy.”
Colombo said that the two-stent approach is optimal in the distal left main because the circumflex is large. On the flip side, cardiologists may prefer placing the stent in the left anterior descending (LAD). However, “in general we prefer not to be provisional in a big vessel like the LAD,” he noted.
“In some situations you may cross over to a two-stent from the very beginning of the procedure because of difficulties rewiring the side branch, he said. “You want to keep the branch open from the very beginning.”
He advised that intravascular ultrasound (IVUS) evaluation is “mandatory” almost every time you implant two-stents.
According to Colombo there are four approaches that can be used during the procedure:
- Culotte: which is more complex;
- Crush: which provides immediate patency with no swelling;
- T-stenting: which has no overlap and is the classic procedure in patients with favorable bifurcation, but may not allow complete coverage; and
- V-stenting: which provides immediate patency for specific anatomy.
Colombo said that use of two of the aforementioned techniques works 90 percent of the time. “One anatomy does not fit all techniques and one technique does not fit all anatomies, but I think use of two of these techniques may be sufficient,” he added.
He offered that the crush technique should be utilized with the two-step kissing-balloon technique.
“We observed that two-step kissing was more effective than one-step kissing for improving the metallic side-branch ostial area,” said Colombo.
Two-step kissing occurs “after you’ve crossed into the side branch then you do isolated high pressure inflation in the side branch to reshape the profusions and deformed stents into a more conventional anatomy.”
According to Colombo, previous trials, like CACTUS, compared the rates of thrombosis when the kissing-balloon technique was utilized. These rates were 0.9 percent versus 6.5 percent, for those treated with the kissing-balloon technique and those without.
He and colleagues developed criteria for AVIO (Angiography versus IVUS optimization). The balloon is selected in accordance to the media diameter in the stenting segment and at the stents edges; the 70 percent criteria can be reduced to 60 percent to lower the risk of per-stent dissection.
Colombo said that the key to successfully completing complex bifurcations is good lesion preparation.
“Unfortunately you are not always blessed with a big chunk of calcium at the beginning of a procedure that indicates that you have to do something,” he said. “When a lesion has a moderate or severe amount of calcium, you have to make sure that you’ve done good lesion preparation.”
One lesion test you may perform is IVUS prior to implanting the stent. Colombo said that if the IVUS catheter doesn’t cross a lesion before stent implantation, then the lesion in unprepared.
To know when a two-stent technique may be beneficial, you must first ask whether or not the bifurcation is true or not. If the answer is no, then you will go directly to the stent provisional period.
“If the answer is yes,” said Colombo,” than you must ask if the side branch is suitable for stenting.” If so, and the disease branch is extended to the side branch, then you could consider use of the two-stent technique.
“This is a very simple approach that does not require a lot of brain and is suitable for the busy interventionalist,” concluded Colombo.