Efficacy of optical frequency domain imaging in detecting peripheral artery disease: the result of a multi-center, open-label, single-arm study.

Optical frequency domain imaging (OFDI) is a high-resolution intracoronary imaging modality with fast automated longitudinal pullback. We aimed to evaluate the ability of performing OFDI from the superficial femoral artery (SFA) to the below-knee (BK) artery. This clinical trial was a multi-center, single-arm, open-label study. The primary endpoint was to obtain a clear image of the intra-vascular lumen from the SFA to the BK artery, specifically > 270° visualization of the blood vessel lumen with > 16/21 cross sections. The proportion of the clear image (≥ 85%) was regarded as confirmatory of the ability of OFDI to visualize the vessel lumen. Overall, 20 patients were enrolled. The proportion of the primary endpoint was 90% (18/20), and the pre-specified criterion was successfully attained. The proportion of the clear image assessed by the operator was 100% (20/20), and an additional statistical analysis for the proportion of the visualization, > 270°, of the blood vessel lumen revealed a significantly higher cut-off value than that for the pre-specified criterion, 85% (p = 0.0315). There were three adverse events not related to OFDI. OFDI achieved acceptable visualization of the vessel lumen without any adverse event related to it. After regulatory approval based on the present study, OFDI will be available as a new option of endovascular imaging for peripheral artery diseases in daily practiceTrial registration: This study was registered in the Japanese Registry of Clinical Trials (jRCT 2052190025, https://jrct.niph.go.jp/latest-detail/jRCT2052190025 ).

Open-label multicenter registry on the outcomes of peripheral arterial disease treated by balloon angioplasty with optical frequency domain imaging in superficial femoral artery and popliteal artery (OCEAN-SFA study).

Although balloon angioplasty for femoropopliteal artery lesions has been associated with restenosis rates of up to 60% at 12 months, the mechanism of restenosis has not been fully evaluated. The aim of this study was to evaluate the relationship between the vascular features observed on optical frequency domain imaging (OFDI) before and after balloon angioplasty of femoropopliteal artery lesions, and restenosis at 6 months. This study was a prospective multicenter single arm study. OFDI was performed before and after balloon angioplasty and plaque characteristics and vascular features, along with de novo lesions, were assessed. The primary outcome was the presence or absence of restenosis 6 months after balloon angioplasty. Residual platelet reactivity was assessed according to VerifyNow platelet reactivity units (PRUs). The number of patients completing 6 months of follow-up was 47, of which 14 had developed restenosis. Maximum thickness of the dissection flap (odds ratio (OR) 2.71; 95% confidence interval [0.9-8.0]; p = 0.071) and lesion length were identified as risk factors for restenosis (OR 1.015; 95% confidence interval [0.001-0.029]; p = 0.039). The mean PRU at the time of treatment in patients with restenosis was significantly higher than in those without restenosis (286.3 ± 82.6 vs. 208.5 ± 03.6, p = 0.026). Long lesions and major dissection on OFDI after balloon angioplasty for femoropopliteal artery lesions increase restenosis at 6 months. In addition, high residual platelet reactivity at the time of EVT may also be a risk factor for restenosis.Clinical Trial Registration Number UMIN000021120.

Correction to: Efficacy of optical frequency­domain imaging in detecting peripheral artery disease: a single­center open­label, single­arm study protocol.

In the original publication of the article, the author group was published without full names and one of the co-authors' name was published incorrectly. The full names of author group and correct co-authors' name are given in this Correction.

Efficacy of optical frequency-domain imaging in detecting peripheral artery disease: a single-center open-label, single-arm study protocol.

Intravascular optical coherence tomography is a high-resolution intracoronary imaging modality, providing a microscopic image of intravascular features. However, it has lower penetration depth than intravascular ultrasound. Recently, a second-generation optical frequency-domain imaging (OFDI) technique has been developed to provide greater penetration depth and faster pullback speed. However, there is little evidence supporting the efficacy of OFDI in patients with peripheral artery disease (PAD) undergoing endovascular treatment (EVT). We aimed to evaluate the ability of OFDI to visualize vessel walls from the superficial femoral artery (SFA) to the below-knee (BK) arteries, as well as the coronary arteries. This clinical trial is a single-center, single-arm, open-label study to be conducted in Japan. A total of 20 patients will be enrolled in this study. The primary endpoint is to obtain a clear image of the intravascular features of the SFA and BK arteries, specifically the visualization of ≥ 270° of the vessel lumen in ≥ 16 out of 21 cross sections. Obtaining clear images in ≥ 85% of cases will be regarded as confirmation of the ability of OFDI to visualize vessel walls from the SFA to the BK arteries. This is the first clinical trial to be conducted accordance with good clinical practice to expand the indications of OFDI for PAD patients undergoing EVT in Japan. The result of this study will help provide another imaging option during EVT in daily practice.