Lower Extremity Revascularization Using Optical Coherence Tomography-Guided Directional Atherectomy: Final Results of the EValuatIon of the PantheriS OptIcal COherence Tomography ImagiNg Atherectomy System for Use in the Peripheral Vasculature (VISION) Study.

PURPOSE: To evaluate the safety and efficacy of a novel optical coherence tomography (OCT)-guided atherectomy catheter in treating patients with symptomatic femoropopliteal disease. METHODS: The VISION trial ( ClinicalTrials.gov identifier NCT01937351) was a single-arm, multicenter, global investigational device exemption study enrolling 158 subjects (mean age 67.2±10.5 years; 87 men) across 20 participating sites. In this cohort, 198 lesions were treated with an average length of 53±40 mm using the Pantheris catheter alone or Pantheris + adjunctive therapy. The primary safety endpoint was the composite of major adverse events (MAEs) through 6 months (objective performance goal 43.2%). Technical success (primary efficacy outcome) was defined as the percent of target lesions with a residual diameter stenosis ≤50% after treatment with the Pantheris device alone (objective performance goal 87.0%). Procedural success was defined as reduction in stenosis to ≤30% after Pantheris ± adjunctive therapy. Tissue specimens retrieved from each treated lesion were histologically analyzed to evaluate the accuracy and precision of OCT image guidance. RESULTS: The primary efficacy outcome was achieved in 192 (97.0%) of the 198 lesions treated with the Pantheris catheter. Across all lesions, mean diameter stenosis was reduced from 78.7%±15.1% at baseline to 30.3%±11.8% after Pantheris alone (p<0.001) and to 22.4%±9.9% after Pantheris ± adjunctive therapy (p<0.001). Of the 198 target lesions, 104 (52.5%) were treated with the Pantheris alone, 84 (42.4%) were treated with Pantheris + adjunctive angioplasty, and 10 (5.1%) with Pantheris + angioplasty + stenting. The composite MAE outcome through 6 months occurred in 25 (16.6%) of 151 subjects. There were no clinically significant perforations, 1 (0.5%) catheter-related dissection, 4 (2%) embolic events, and a 6.4% clinically driven target lesion revascularization rate at 6 months. The 40-lesion chronic total occlusion (CTO) subset (mean lesion length 82±38 mm) achieved a similar significant reduction in stenosis to 35.5%±13.6% after Pantheris alone (p<0.001). Histological analysis of atherectomy specimens confirmed <1% adventitia in 82.1% of the samples, highlighting the precision of OCT guidance. Characterization of the OCT-guided lesions revealed evidence of an underestimation of disease burden when using fluoroscopy. CONCLUSION: OCT-guided atherectomy for femoropopliteal disease is safe and effective. Additionally, the precision afforded by OCT guidance leads to greater removal of plaque during atherectomy while sparing the adventitia.

Optical coherence tomography: guided therapy of in-stent restenosis for peripheral arterial disease.

Approximately 27 million people in Europe and North America currently have peripheral arterial disease (PAD). The endovascular treatment of stenosis or blocked peripheral arteries in PAD include percutaneous transluminal angioplasty with or without a drug coated balloon (DCB), atherectomy (rotational, directional, orbital or laser), and stenting. The development of next generation peripheral stents and drug-coated stents have led to the improved treatment of complex superficial femoral artery (SFA) lesions, and consequently increased their usage. Additionally, the technologies developed for PAD intervention have further improved the overall adoption of endovascular procedures leading to increased utilization of stents to address procedural dissections (bailout stenting), as support scaffolding for complex lesions, and to prevent preventing elastic recoil post balloon angioplasty. For example, bail-out stenting after DCB angioplasty has been reported to be as high as 40% in long lesions and as high as 46% in chronic total occlusions lesions. In total, approximately 200,000 stents are placed annually in the femoral and popliteal arteries in PAD patients in the USA, with 30% to 40% of these stents expected to develop in-stent restenosis within 2-3 years of implantation. Accordingly, the treatment of in-stent restenosis (ISR) remains a substantial healthcare burden. Few technologies reported on improved ISR patency rates as compared to PTA treatment alone, including drug-eluting stents and balloons, laser atherectomy or covered stents. However, the reported longer-term patency for ISR remains suboptimal creating a cyclical treatment pattern that burdens patients and providers. In this review, we present the rational and clinical evidence for utilizing OCT-guided therapies for the treatment of ISR for PAD.

Value of absence of a transient myocardial perfusion defect during stress myocardial perfusion study in patients undergoing major vascular surgery.

Pre-operative cardiac assessment is important in the evaluation of patients undergoing major vascular surgery. Our study aims to evaluate the value of absence of a transient myocardial perfusion defect during radionuclide myocardial perfusion study for prediction of cardiac events (myocardial infarction, sudden cardiac death, unstable angina, coronary artery revascularization and congestive heart failure) in patients undergoing major vascular surgery. We studied 63 consecutive patients (ages 35-83 [avg. 64], male 39, female 24) with radiographically proven, abdominal aortic aneurysm or severe aortofemoral occlusive disease who underwent major vascular surgery (abdominal aortic aneurysm repair [38] or aortofemoral bypass [25]). The subjects all had multiple coronary artery risk factors (hypertension 48, diabetes 10, hyperlipidemia 23, tobacco use 39, family history of coronary artery disease 10), but a negative pre-operative stress myocardial perfusion study for myocardial ischemia. Of these 63 patients, 17 patients were able to exercise and achieve their adequate 85% maximal predicted heart rate. Thirty-eight patients received adenosine infusion of 140 microg/kg/min for 6 min. Six patients received dipyridamole infusion of 0.56 mg/kg over 4 min. Two patients received dobutamine infusion at 5, 10, 20, 30, and 40 mg/kg/min. Of the 63 patients, 60 received 3-4 mCi of thallium-201 ((201)Tl) and 3 patients received 8-9 mCi of technetium-99m (99mTc) at rest and 25-30 mCi 99mTc during stress. The subjects all underwent major vascular surgery and were followed up to one year for any cardiac events. Of the 63, who underwent pre-operative cardiac assessment with myocardial perfusion testing, 25 had a fixed myocardial perfusion defect (scar) and none had evidence of transient myocardial perfusion defect (ischemia). One subject had coronary artery bypass grafting 11 months after aortofemoral bypass surgery. One died from a stroke one month after aortofemoral bypass surgery. Of the remaining 61 patients, none had any cardiac events up to one year after major vascular surgery.