Assessment of Vascular Patency and Inflammation with Intravascular Optical Coherence Tomography in Patients with Superficial Femoral Artery Disease Treated with Zilver PTX Stents

PURPOSE

Zilver PTX nitinol self-expanding drug-eluting stent with paclitaxel coating is effective for treatment of superficial femoral artery (SFA) disease. However, as with any stent, it induces a measure of vascular inflammatory response. The current clinical trial (NCT02734836) aimed to assess vascular patency, remodeling, and inflammatory markers with intravascular optical coherence tomography (OCT) in patients with SFA disease treated with Zilver PTX stents.

METHODS

Serial OCT examinations were performed in 13 patients at baseline and 12-month follow-up. Variables evaluated included neointimal area, luminal narrowing, thrombus area, stent expansion as well as measures of inflammation including, peri-strut low-intensity area (PLIA), macrophage arc, neovascularization, stent strut apposition and coverage.

RESULTS

Percentage of malapposed struts decreased from 10.3 ± 7.9% post-intervention to 1.1 ± 2.2% at 12-month follow-up, but one patient showed late-acquired stent malapposition (LASM). The percent of uncovered struts at follow-up was 3.0 ± 4.5%. Average expansion of stent cross-sectional area from baseline to follow-up was 35 ± 19%. The average neointimal area was 7.8 ± 3.8 mm². Maximal luminal narrowing was 61.1 ± 25.0%, and average luminal narrowing was 35.4 ± 18.2%. Average peri-strut low-intensity area (PLIA) per strut was 0.017 ± 0.018 mm². Average number of neovessels per mm of stent was 0.138 ± 0.181. Average macrophage angle per frame at follow-up was 7 ± 11°. Average thrombus area at follow-up was 0.0093 ± 0.0184 mm².

CONCLUSION

At 12-month follow-up, OCT analysis of Zilver PTX stent shows outward remodeling and minimal neointimal growth, but evidence of inflammation including PLIA, neovessels, thrombus and macrophages.

SUMMARY

Thirteen patients with PAD had paclitaxel-coated stents implanted in their SFAs and were then imaged with OCT at baseline and 12-month follow-up. OCT proxy metrics of inflammation were quantified.

Primary endpoint results of the OMEGA Study: One-year clinical outcomes after implantation of a novel platinum chromium bare metal stent

BACKGROUND/PURPOSE

Bare metal stents (BMS) have similar rates of death and myocardial infarction (MI) compared to drug-eluting stents (DES). DES lower repeat revascularization rates compared to BMS, but may have higher rates of late stent thrombosis (ST) potentially due to impaired endothelialization requiring longer dual anti-platelet therapy (DAPT). OMEGA evaluated a novel BMS designed to have improved deliverability and radiopacity, in comparison to currently available platforms.

METHODS/MATERIALS

OMEGA was a prospective, multicenter, single-arm study enrolling 328 patients at 37 sites (US and Europe). Patients received the OMEGA stent (bare platinum chromium element stent) for the treatment of de novo native coronary artery lesions (≤28 mm long; diameter ≥2.25 mm to ≤4.50mm). The primary endpoint was 9-month target lesion failure (TLF: cardiac death, target vessel-related MI, target lesion revascularization [TLR]) compared to a prespecified performance goal (PG) based on prior generation BMS. All major cardiac events were independently adjudicated. DAPT was required for a minimum of 1 month post procedure.

RESULTS

In the OMEGA study, the mean age was 65; 17% had diabetes mellitus. The primary endpoint was met; 9 month TLF rate was 11.5%, and the upper 1-sided 95% confidence bound of 14.79% was less than the prespecified PG of 21.2% (p<0.0001). One-year event rates were low including a TLF rate of 12.8% and an ST rate of 0.6% at 12 months.

CONCLUSIONS

One-year outcomes of OMEGA show low rates of TLF, revascularization and ST. This supports safety and efficacy of the OMEGA BMS for the treatment of coronary artery disease.

A poly-N-acetyl glucosamine hemostatic dressing for femoral artery access site hemostasis after percutaneous coronary intervention: a pilot study

BACKGROUND

Arterial puncture closure devices have improved time to hemostasis and ambulation after percutaneous coronary intervention (PCI) relative to traditional manual compression, though complication rates for both methods leave room for improvement. In a pilot registry, the authors evaluated a topical hemostatic dressing containing poly-N-acetyl glucosamine (p-GlcNAc) post PCI in fully anticoagulated patients.

METHODS AND RESULTS

In 100 patients undergoing PCI via the common femoral artery in the short-stay unit, the p-GlcNAc hemostatic dressing was applied with 15 minutes of manual compression at arterial access sites after arterial sheath removal. Procedural antiplatelet and anticoagulation therapies were aspirin, clopidogrel and bivalirudin. Patients were observed during 2 hours of bed rest and attempted to ambulate 2 hours post hemostasis. Effectiveness was assessed based on times to hemostasis and ambulation. Data were stratified by time elapsed since bivalirudin bolus or discontinuation of infusion (30 minutes, > 30-60 minutes, > 60 minutes). Mean time to hemostasis was 15.5 minutes. Mean time from hemostasis to ambulation was 2.08 hours; 87% of patients ambulated at 2 hours. Sheaths were removed at a mean 40.38 minutes after discontinuing bivalirudin. Anticoagulation status (as assessed by time since discontinuation of bivalirudin) did not influence time to hemostasis or ambulation. There was a single major complication (pseudoaneurysm), two minor rebleeds requiring additional manual compression, and 1 hematoma > 5 cm.

CONCLUSIONS

This p-GlcNAc topical hemostatic dressing safely achieved hemostasis at arterial access sites and early ambulation, even with nearly immediate sheath removal after PCI with systemic anticoagulation using bivalirudin.