CLD last spoke to Dr. Sharma about the Runthrough NS wire (Terumo Interventional Systems) in 20081,2 and in 20093. Below, he shares why the cath lab at The Mount Sinai Hospital continues its decade-plus use of the Runthrough NS.
Can you share a bit of your history with this wire?
We were an early adopter of the Runthrough NS back in 2008. Starting in 2000, we tended to use the high torque floppy guidewires, then the Balance Middleweight (BMW) (Abbott Vascular), and then the Runthrough NS guidewire came out. We experienced instantaneous success with its use, practically overnight. We used it on every interventional case, although some interventionalists preferred the Prowater or Sion Blue (both Asahi Intecc), but eventually, more and more doctors became used to using the Runthrough NS.
Now our policy at Mount Sinai Hospital is that for every percutaneous coronary intervention (PCI), we open the Runthrough NS. It is at 100% use in our interventions. If any support is needed, such as for a side branch, then we usually open a hydrophilic wire like a Fielder (Asahi Intecc). The Runthrough NS has outperformed any wire.
About two years ago, the Runthrough NS experienced an inventory disruption. During that period, we tried every new guide wire available from other companies. Nothing came close to the performance of the Runthrough NS. It was a big setback in that we were spending more time by using other wires, sometimes more than one wire, when we used to need only a single Runthrough NS wire. We could not find the Runthrough NS wire’s 1:1 torque in other wires. From 2008 to almost 2017, we didn’t try any other wire, but in 2017, because Runthrough NS was unavailable, it led to our exploration of other wires. Every day, every case, we missed not having the Runthrough NS wire, and when it became available again, we celebrated. Not having the Runthrough NS increased our procedure time, which was difficult. No other wire gave us that same kind of support and torque, even after trialing the latest wires from every company. As soon as the Runthrough NS wire was back, all the other wires disappeared from our lab. We went back to the same 100% use of the Runthrough NS wire for interventions. The Runthrough NS is the only wire I recommend to people, either the 180 cm or exchange length. If we have a tough case, perhaps a chronic total occlusion, we use an over-the-wire system, go through the lesion and use a Finecross catheter (Terumo), which is an over-the-wire delivery catheter. As soon as we go distally, if atherectomy is not being done, we use an exchange-length Runthrough NS wire, remove the over-the-wire delivery catheter, and then use balloon and insert the stent. About 15% of our Runthrough NS use is the 300 cm exchange length in complex cases, most likely total occlusions. After crossing, we go with the exchange-length Runthrough NS and then do the rest of the intervention. With the Runthrough, you can always cut it on the end as well to make it short after completing the exchange. That is the history of the Runthrough wire at Mount Sinai. More importantly, when the Runthrough NS was temporarily unavailable, its value became even more evident.
You mentioned the 1:1 torque of the Runthrough NS. What other features do you find valuable?
The 1:1 torque is key. Numbers 1-3? 1:1 torque, 1:1 torque, 1:1 torque. Next would be tip retention and finally, the ability to provide support. It remains in the lumen, it very rarely causes perforation, and it provides adequate body to deliver your devices so you don’t have to use GuideLiners (Teleflex) and other fancy catheters and so forth.
Why is the 1:1 torque so important?
It is key. Anatomy is often quite difficult in terms of tortuosity, and unless your wire is giving you that support and 1:1 torque, it takes more time to advance through a long, tortuous lesion. The 1:1 torque of the Runthrough NS cuts down time by half. Let’s say we are not using a Runthrough NS and are using another wire, and there is a long lesion of the mid left anterior descending (LAD) coronary artery. We will bring the wire into the proximal LAD, but the wire goes into all the branches. We pull back, try again, but then it goes into another branch, and rather than going forward, we are going through the branches. With the Runthrough NS, you rotate the wire a little bit, it advances in the lumen, and you can go quickly, meaning what would take 50-60 seconds with another wire takes 10-20 seconds with the Runthrough NS.
How do you find the Runthrough NS for teaching purposes?
There is now very little teaching on wires. Some people say that you are not teaching fellows the interventional technique, because this wire does most of the work. But I say, why not? That is the advancement of science! The same thing we used to struggle with 10-20 years ago, now the catheters are better, stents are better, and balloons are better. If the fellows are doing a good job without much teaching, if they have a wire and they are successfully using it, to me, that is positive. When the Runthrough NS was not available — and it was in the middle of a fellowship, meaning the fellows had used a Runthrough NS in the first 3-4 months and then it was gone for several months — everyone felt the pinch of not having the Runthrough NS available. There was definitely an increased time consumption as we had to use other wires, prolonging our interventional cases.
Certainly it seems the reduction in wire usage and time with the Runthrough NS would help from an economic perspective.
Definitely. Our wire usage per case at present is about 1.5 or 1.6. Why? In more than half of the cases, we open second wires for the side branch. Of course, in many cases, you do have to use more than one Runthrough NS because of the side branch use and now you are going into a different vessel. During the period when the Runthrough NS was unavailable, I can’t quantify exact numbers, but I can tell you our wire usage became almost 2-plus for each case.
In 2008, you indicated that before Runthrough NS, the number of wires per intervention was at 2.7.2
In the past, we used to do multiple interventions at the same time. Now we just treat those lesions that are determined by fractional flow reserve (FFR) measurement to be ischemia producing. Our stent usage, which before was almost 1.9 per case, now is more like 1.4, because we follow FFR guidance, which typically instructs us to do fewer vessel interventions, as showed in the FAME trial. In the trial’s angiography-only group,100% of patients underwent PCI, and in the FFR-guided group, only 63% of the lesions underwent PCI. That alone accounts for a 30-40% reduction in stenting and interventions.
Does perforation remain a concern?
Yes, of all the wires that we use, the Runthrough NS remains at the bottom of the list of number of wire perforations.
Any final thoughts?
At Mount Sinai, we continue to have more complex cases being referred to us, our interventional volume has increased, and we are happy that the Runthrough NS is available so we can work quickly and safely to help our patients.
Disclosures: Dr. Sharma reports speakers honorarium for Abbott Vascular, Boston Scientific Corporation, and CSI.
Dr. Samin Sharma can be contacted at firstname.lastname@example.org.
- Sharma S. Experience with a new guidewire: the Terumo Runthrough NS. Cath Lab Digest. 2008 March; 16(3). Available online at https://www.cathlabdigest.com/articles/Experience-a-New-Guidewire-The-Terumo-Runthrough-NS. Accessed November 20, 2019.
- Sharma S. The Runthrough NS guidewire: lessons after 2,000 uses. 2008 September; 16(9). Available online at https://www.cathlabdigest.com/articles/The-Runthrough-NS-Guidewire-Lessons-after-2000-uses. Accessed November 20, 2019.
- Sharma S. “The Runthrough has become our workhorse wire.” Cath Lab Digest. 2009 November; 17(11): 48-49. Available online at https://www.cathlabdigest.com/content/runthrough-has-become-our-workhorse-wire. Accessed November 20, 2019.