Spiral Flow Prosthetic Grafts In lower extremity bypasses: 1-year results and beyond
Purpose
The aim of this single centre study was to compare the primary and secondary patency rates at one year of conventional PTFE infrainguinal bypass grafts with a new Spiral Laminar Flow ePTFE graft.
Methods
Prospective data on primary and secondary patency rates and interventions/complications was gathered on 68 infrainguinal bypasses using Spiral Flow Grafts from February 2011 to October 2014. The data on 136 standard grafts was gathered retrospectively on all infrainguinal PFTE grafts over a six year period from Jan 2003 to Dec 2008. Data was obtained from case notes and surveillance scans. There were no changes in case mix or operative/interventional procedures between the two groups/time periods. Data was also obtained on type of operation, mortality and amputation rates. At one year, data for 54 Spiral Flow Grafts and 124 standard grafts was available for review.
Patient Demographics
| Spiral Flow | Conventional ePTFE | |
|---|---|---|
| Age | 69.6 mean (47-92) | 70.3 (45-93) |
| Sex | 78% male | 48% male |
| Critical ischaemia | 53% | 55% |
Level of Implantation
| Spiral Flow | Conventional ePTFE | |
|---|---|---|
| Above Knee | 48% | 13% |
| Below Knee / Tibial / Complex | 52% | 87% |
Vein cuffs were added to all BK/distal anastomoses.
Spiral Flow was seen on post-operative imaging at all distal anastomoses and run-off vessels.
Results
Primary patency (Actuarial %)
| Spiral Flow | Conventional ePTFE | |
|---|---|---|
| Overall | 76% | 48% |
| Above Knee | 77% | 50% |
| Below Knee / Tibial / Complex | 61% | 48% |
Secondary patency (Actuarial %)
| Overall | 87% | 55% |
|---|---|---|
| Above Knee | 88% | 71% |
| Below Knee / Tibial / Complex | 79% | 53% |
| Amputation rate | 2% | 10% |
Conclusions
Benchmarked against conventional grafts highlights a 30% actuarial improvement in primary and secondary patency. Results out to 3 years, particularly of more complex grafts, would appear to indicate a sustained patency advantage over conventional grafts. Significantly encouraging initial results to warrant continued usage and further long term data acquisition.