Clinical expert consensus document on standards for lower extremity artery disease of imaging modality from the Japan Endovascular Treatment Conference

Factors associated with recurrence after drug-coated balloon therapy for femoropopliteal in-stent restenosis

PURPOSE

To evaluate the impact of intravascular ultrasound (IVUS)-evaluated tissue morphology on recurrence following drug-coated balloon (DCB) angioplasty for the treatment of femoropopliteal in-stent restenosis (FP-ISR).

METHODS

This study was a single-center, retrospective, observational study. Study subjects were 65 FP-ISR lesions (mean lesion length: 165 ± 88 mm, occlusive restenosis: 25%) in 53 patients (age: 76 ± 8, diabetes mellitus: 66%) who underwent DCB angioplasty and whose IVUS data of tissue morphology were available. The morphology of ISR was determined by dominant tissue and classified into two group with and without fibrous tissue. Fibrous tissue was defined as the absence of calcification, equal to or more advanced than the echo luminance of the outer membrane, but without acoustic shadow. The outcome measure was recurrence-ISR, and cox proportional hazards models were used to explore factors associated with recurrence-ISR.

RESULTS

During mean follow-up period of 16 ± 12 months, recurrence-ISR was found in 32% (n = 21). The tissue morphology of FP-ISR before DCB angioplasty was distributed with 68% (n = 44) in fibrous tissue group and with 33% (n = 21) in non-fibrous tissue group. Factors associated with recurrence-ISR were drug-eluting stent (DES)-ISR (hazard ratio [HR]: 4.329; 95% confidence interval [CI]: 1.572-11.918, P = 0.005) and non-fibrous tissue (HR: 4.595; 95% CI: 1.484-14.228, P = 0.008).

CONCLUSION

The current study revealed IVUS-evaluated tissue morphology and DES-ISR lesions were significantly associated with recurrence FP-ISR after DCB angioplasty.

INtravaScular OptIcal Frequency Domain ImaGing EvaluaTion of the Femoropopliteal Lesion With JETSTREAM Atherectomy (INSIGHT JETSTREAM)

BACKGROUND

There have been no prior reports of detailed evaluations using intravascular imaging during Jetstream treatment.

AIMS

This study, therefore, aimed to investigate the effects of calcification characteristics and wire bias on lumen gain in Jetstream atherectomy using optical frequency domain imaging (OFDI).

METHODS

This study enrolled consecutive patients who underwent OFDI-guided Jetstream atherectomy with 1.85 mm, 2.4 mm blade down (BD), and 2.4 mm blade up (BU). Cross-sections were categorized into three groups based on OFDI findings before Jetstream atherectomy: fibrous plaques (FPs), calcified protrusions (CPs), and eruptive calcified nodules (ECNs).

RESULTS

Twenty-seven patients (36 limbs) were enrolled, and 1502 cross-sections were serially analyzed. There were 186 FPs, 753 CPs, and 563 ECNs. The acquired lumen gain after all atherectomy steps was significantly larger in the ECNs group than in the CPs and FPs groups. ECNs had the strongest effect on the variability in the lumen gain. In the effect of wire bias on the degree of debulking, a significant correlation was observed between wire distance and lumen gain in 1.85- and 2.4-mm BD atherectomy procedures. However, in the 2.4-mm BU procedure, no significant correlation was recorded.

CONCLUSIONS

Jetstream atherectomy for ECNs can result in greater lumen gain. In the 1.85- and 2.4-mm BD atherectomy procedures, wire bias may be involved in lumen gain, whereas in the 2.4-mm BU procedure, lumen gain is obtained regardless of wire bias. In Jetstream atherectomy procedures, a detailed assessment using OFDI may contribute to predicting the degree of debulking.

TRIAL REGISTRATION

UMIN ID: UMIN000054588. https://center6.umin.ac.jp/cgi-bin/ctr/ctr_view_reg.cgi?recptno=R000061997.

JET EDGE Technique: Results of a Single-Center Retrospective Study of Jetstream Atherectomy Using the Guidewire Bias Method for Eccentric Severely Calcified Lesions

BACKGROUND

The Jetstream device is an effective treatment option for debulking calcified lesions; however, it carries a risk of damaging the healthy vessel wall. This study aimed to evaluate the safety and efficacy of the Jetstream device combined with wire bias adjustments for treating eccentric calcified lesions.

AIMS

The aim of this study was to evaluate the safety and efficacy of JET EDGE technique for treating eccentric calcified lesions.

METHODS

This single-center, retrospective, nonrandomized observational study was conducted at a cardiovascular department in Japan. It included patients aged ≥ 20 years with eccentric calcified lesions (Rutherford classification 3-6) who underwent endovascular therapy using the Jetstream catheter for femoropopliteal disease between October 2022 and September 2024.

RESULTS

Twenty-eight lesions in 28 patients (28.6% female; mean age: 76.9 ± 7.3 years) with a mean follow-up period of 409 ± 174 days were analyzed. All lesions were graded 3 or 4 on the peripheral arterial calcium scoring system. The procedural success rate was 96.4%. No vascular perforations or medial layer damage were observed on imaging following the use of the Jetstream catheter. The 1-year Kaplan-Meier estimates for primary patency, freedom from major adverse limb events, and freedom from target lesion revascularization were 88.6%, 88.1%, and 91.3%, respectively.

CONCLUSIONS

This retrospective study demonstrates that eccentric calcified lesions, which pose a risk of damaging the healthy vessel wall during treatment with the Jetstream catheter, can be safely treated by adjusting the wire bias during the procedure.

Risk factors of incident acute limb ischemia after contemporary femoropopliteal endovascular revascularization from a multicenter registry: A retrospective observational study

Purpose

To investigate the incidence of acute limb ischemia (ALI) among patients with femoropopliteal (FP) lesions treated with contemporary endovascular therapy (EVT) and to identify risk factors for ALI after FP-EVT.

Methods

In this retrospective multicenter registry, we analyzed patients with lower extremity artery disease having FP lesions who underwent EVT between 2017 and 2021. We investigated the incident ALI related to the index EVT and its risk factors. We also assessed the prognosis after the incident ALI.

Results

During a median follow-up of 35.3 months, incident ALI was observed in 72 of 3102 patients (2.3%). The Rutherford classification I/IIa/IIb/III was 50.0%, 30.5%, 18.1%, and 1.4%, respectively. Variables independently associated with the incident ALI were chronic limb-threatening ischemia (CLTI; hazard ratio, 1.83; p = 0.015), reference vessel diameter < 6 mm (2.39; p = 0.011), lesion length >25 cm (3.35; p = 0.005) with its time interaction (0.72 per 1 year; p = 0.042), P2/3 segment involvement (2.73; p < 0.001), chronic total occlusion (CTO; 3.40; p < 0.001), and in-stent restenosis/occlusion (3.21; p < 0.001). During a median follow-up of 12.8 months after the ALI event, all-cause mortality was 27.8% and the rate of major amputation was 6.9%.

Conclusions

The FP-EVT showed that the occurrence of ALI was 2.3% during a median follow-up of 35.3 months. The independent predictors of the ALI event were CLTI, small vessels, long lesions, CTO, and in-stent restenosis; however, the impact of lesion length was attenuated over time after the index EVT.

Impact of body mass index on mortality, limb amputation, and bleeding in patients with lower extremity artery disease undergoing endovascular therapy

The relation between Body Mass Index (BMI) and adverse outcomes after endovascular therapy (EVT) for patients with lower extremity artery disease (LEAD) remains incompletely understood. From April 2010 to March 2020, 199 consecutive patients who underwent EVT for LEAD were retrospectively analyzed. The patients were divided into three groups based on BMI; underweight < 18.5 kg/m2, normal weight ≥ 18.5 and < 25.0 kg/m2, and overweight ≥ 25.0 kg/m2. The endpoint of this study was a composite of all-cause mortality, major amputation, and major bleeding. Patients who were underweight often exhibited anemia (53.3 vs. 22.3 vs. 15.4%, respectively; p = 0.001) and severe chronic kidney disease (50.0 vs. 30.8 vs. 20.5%, respectively; p = 0.03). Furthermore, these patients had higher incidences of Trans-Atlantic Inter-Society Consensus class C or D lesions (40.0 vs. 20.0 vs. 10.3%, respectively; p = 0.01). During the median follow-up duration of 3.6 years (interquartile range: 1.2 to 6.7 years), there were 73 incidents of the composite endpoint. When the overweight group was assigned as the reference group, the adjusted hazard ratios for the composite endpoint for the underweight and normal weight patients were 3.67 (95% confidence interval [CI] 1.39-10.83, p = 0.008) and 2.35 (95% CI 1.06-6.23, p = 0.03), respectively. Kaplan-Meier curve demonstrated that the freedom from the composite endpoint for underweight, normal weight, and overweight patients was 41.6%, 60.0%, 83.8%, respectively (p < 0.001). These results suggest that there was an inverse association between BMI and adverse outcomes composed of mortality, limb amputation, and bleeding in patients with LEAD undergoing EVT.

The Vascular Response After Balloon Angioplasty of Infrapopliteal Intermediate Stenosis Evaluated by Optical Frequency Domain Imaging

BACKGROUND

We often experience worsening of stenosis by balloon angioplasty of infrapopliteal (IP) lesion compared with the initial stenosis. However, reports on this phenomenon are limited.

AIMS

The main purpose of this study is to evaluate vascular response after balloon angioplasty of IP artery stenosis.

METHODS

Thirteen patients (15 arteries) who underwent endovascular treatment (EVT) and follow-up angiography with optical frequency domain imaging (OFDI) of intermediate IP stenosis were included. Serial OFDI images at 3 time points (before and after EVT and at follow-up) were analyzed. Diameter and area of external elastic lamina, internal elastic lamina, and lumen were measured, and plaque area and plaque burden (PB) were calculated. PB before EVT was classified into mild, moderate, and severe by 0%-20%, 21%-40%, and 41%-60%, respectively.

RESULTS

Analyzed were 229 cross sections. External elastic lamina diameter did not change significantly among three time points (3.8 ± 0.5 [95% confidence interval (CI): 3.7 to 3.9] mm, 3.9 ± 0.4 [95% CI: 3.8 to 4.0] mm, 3.9 ± 0.4 [95% CI: 3.8 to 4.0] mm, p = 0.06). Lumen area increased after EVT but became smaller at follow-up than before EVT (4.5 ± 1.5 [95% CI: 4.3 to 4.7] mm2, 5.3 ± 1.3 [95% CI: 5.1 to 5.5] mm2, 3.7 ± 1.2 [95% CI: 3.5 to 3.9] mm2, p < 0.001). Plaque area became smaller after EVT and larger at follow-up than before EVT (3.0 ± 1.7 [95% CI: 2.8 to 3.2] mm2, 2.4 ± 1.5 [95% CI: 2.2 to 2.6] mm2, 4.0 ± 1.6 [95% CI: 3.8 to 4.2] mm2, p < 0.001). Lumen area was significantly smaller at follow-up than before EVT in mild and moderate PB groups, but it was not different in severe PB group (mild PB group: 5.1 ± 1.5 [95% CI: 4.7 to 5.5] mm2 vs. 4.0 ± 1.3 [95% CI: 3.7 to 4.3] mm2, p < 0.001, moderate PB group: 4.6 ± 1.3 [95% CI: 4.4 to 4.8] mm2 vs. 3.6 ± 1.2 [95% CI: 3.4 to 3.8] mm2, p < 0.001, severe PB group: 3.0 ± 1.4 [95% CI: 2.5 to 3.5] mm2 vs. 3.1 ± 1.0 [95% CI: 2.7 to 3.5] mm2, p = 0.93).

CONCLUSIONS

Balloon angioplasty of intermediate IP artery stenosis with mild or moderate PB led to smaller lumen area at follow-up than before EVT.

Application of Drug-Eluting Stent With Drug-Coated Balloon Strategy for the Endovascular Treatment of Long-Segment Femoropopliteal Artery Disease

PURPOSE

Endovascular therapy (EVT) has emerged as a primary approach for managing femoropopliteal artery (FPA) lesions, leveraging drug-eluting stents (DESs), and drug-coated balloons (DCBs), to enhance clinical outcomes. Although a full DES coverage strategy is effective in treating complex lesions, concerns over long-term complications prompt the exploration of alternative strategies. The aim of this study was to investigate clinical result of combination therapy of DES with DCB and compare them with full DES implantation.

MATERIALS AND METHODS

This retrospective, single-center study analyzed 131 patients with occlusive FPA lesions treated at our institution between 2019 and 2022. Patients with Rutherford classification stages 2 to 5 who underwent successful EVT were included. The study compared the outcomes of the drug-within-drug (DWD) strategy, ie, combining DES for failed vessel preparation segments and DCB for successful ones, with those of full DES implantation. The primary outcomes were the primary patency rates, and the secondary outcomes included clinically-driven target lesion revascularization (CD-TLR) rates, restenosis patterns, and survival outcomes.

RESULTS

Of the 131 patients initially considered, 118 met the inclusion criteria, with 45 in the DWD group and 73 in the full metal jacket (FMJ) stent group. The DWD group demonstrated equivalent 1-year primary patency rates (85.3%) to the FMJ group (87.9%, p=0.239). Similarly, no significant differences in CD-TLR rates were found between the 2 groups. The restenosis patterns and subsequent treatment strategies were not significantly different.

CONCLUSION

The DWD strategy offers a viable alternative to full DES coverage in treating long-segment FPA lesions, with comparable restenosis and target lesion revascularization (TLR) rates. This approach may mitigate risks associated with full-length stenting, such as thrombosis, and challenges in repeat revascularizations by tailoring treatment to lesion characteristics. The DWD strategy represents a promising approach for complex FPA lesions, providing a balanced solution that potentially reduces long-term complications while maintaining effective patency and revascularization rates.

CLINICAL IMPACT

The efficacy of drug-eluting stents (DES) in treating femoropopliteal artery (FPA) lesions has been well demonstrated. However, concerns remain regarding complications such as thrombotic occlusion and aneurysmal degeneration, especially when full stemt coverage of whole lesions is performed. The "Drug-with-Drug" (DWD) strategy, which involves implanting DES only at sites with severe dissection or residual stenosis after pre-balloon dilation and using drug coated balloons (DCB) for segments successfully prepared without stenting, has shown comparable outcomes to full stent coverage. Unlike traditional bailout stenting or spot stenting, the DWD approach maximizes the benefits of drug technology and presents a valuable option for treating long-segment FPA lesions.

Three-year outcomes of contemporary endovascular treatment in over 25-cm femoropopliteal artery disease from a retrospective multicenter registry: A retrospective observational study

BACKGROUND

Endovascular therapy (EVT) is often performed for diffuse femoropopliteal lesions. This study investigated 3-year patency and clinical outcomes in patients with EVT-treated femoropopliteal lesions >25 cm.

METHODS

This retrospective multicenter registry analyzed patients who presented with lower extremity artery disease having femoropopliteal lesions >25 cm who underwent EVT between 2017 and 2021. The primary outcome was restenosis 3 years after EVT.

RESULTS

Overall, 504 patients with 614 lesions undergoing EVT for diffuse femoropopliteal lesions were enrolled. The prevalence of restenosis was 184.3 per 1000 lesion-years. Kaplan-Meier estimate of freedom from restenosis was 58.6% at 3 years. In the multivariate Poisson regression model, female sex (adjusted incidence risk ratio: 1.54; p = 0.003), cilostazol use (0.44; p < 0.001), revascularization history (1.87; p = 0.001), P3 involvement (2.09; p < 0.001), and reference vessel diameter <5 mm (1.88; p < 0.001) were associated independently with restenosis risk. The accumulation of these factors was associated with a lower rate of freedom from restenosis; the Kaplan-Meier estimates of the rates were 49.3% and 22.4% in the subgroups with two and more risk factors, respectively, while they were 81.1% in patients without any risk factors and 70.3% in those with one risk factor.

CONCLUSIONS

Female sex, nonuse of cilostazol, revascularization history, P3 involvement, and small vessels were associated with high restenosis risk after EVT for diffuse femoropopliteal lesions. Although patients with multiple risk factors have a low patency rate, EVT offers an acceptable patency rate for those with fewer risk factors.

Impact of post-procedural peripheral fractional flow reserve after drug-coated balloon angioplasty in femoropopliteal lesions

PURPOSE

The aim of this study was to determine if postprocedural peripheral fractional flow reserve (pFFR) is associated with patency one year after drug-coated balloon (DCB) angioplasty for femoropopliteal (FP) lesions.

MATERIALS AND METHODS

Forty-five consecutive patients having 49 de novo FP lesions were enrolled in this prospective, observational study conducted from April 2022 to Aug 2023. The pFFR was measured under hyperemic conditions after the administration of 30 mg of papaverine. The relationship between pFFR and restenosis 12 months after the procedure was determined using receiver operating characteristic (ROC) curve analysis.

RESULTS

The one-year follow-up was completed for 47 lesions (95.9 %). Restenosis was detected in 7 lesions (14.9 %). Postprocedural pFFR was significantly higher in the nonrestenosis group compared with the pFFR in the stenosis group (0.95 ± 0.054 vs. 0.88 ± 0.090, p = 0.010). The optimal pFFR cutoff value for predicting restenosis was 0.92 (sensitivity, 0.824; specificity, 0.600). The area under the curve for pFFR was numerically higher than the area under the curve for minimum lumen area (0.73 vs. 0.64, p = 0.22). Rates of freedom from restenosis at one year were significantly higher in the pFFR >0.92 group compared with the pFFR ≤0.92 group (p = 0.0042).

CONCLUSION

Postprocedural pFFR was associated with patency at one year after DCB angioplasty for FP lesions.

Evaluation of nontarget lesions in femoropopliteal disease using near-infrared spectroscopy intravascular ultrasound imaging

BACKGROUND

In coronary artery disease (CAD), lipid-core-containing plaque (LCP) in nontarget lesions detected using near-infrared spectroscopy intravascular ultrasound (NIRS-IVUS) was related to increased major adverse cardiovascular events in patients with CAD. In the endovascular therapy field, few previous studies using NIRS-IVUS revealed the presence of LCPs in severe stenotic lesions of femoropopliteal disease.

AIM

This study aimed to assess the plaque morphology of nontarget lesions, especially LCPs, and compare it with that of target lesions using NIRS-IVUS in patients with femoropopliteal disease.

METHODS

This single-center prospective observational study included 14 patients who underwent endovascular therapy for FP disease. NIRS-IVUS assessment was performed on the entire FP arterial segment. Forty-one LCP lesions with a maximum lipid-core burden index in any 4-mm region (max LCBI4mm) > 100 were detected using NIRS-IVUS. We evaluated the patient and lesion characteristics. LCP lesions were divided into the target (n = 18) and nontarget (n = 23) lesion groups for comparison.

RESULTS

Patient characteristics were notable for advanced age (76.8 ± 6.6 years); high proportion of males (78.7%); and high incidence of hypertension (100%), dyslipidemia (78.6%), diabetes (64.3%). Regarding NIRS findings, the target lesion group exhibited a significantly smaller proportion of LCPs concerning the lesion length (25.9 ± 15.7% vs. 50.6 ± 29.2%, p = 0.002) than the nontarget lesion group. Conversely, there were no significant differences in the value of max LCBI4mm (284.4 ± 153.4 vs. 289.5 ± 113.1, p = 0.90), length of LCP lesion (9.8 ± 9.7 mm vs. 10.7 ± 6.9 mm, p = 0.74), and distribution of LCPs (p = 0.08) between the groups. In addition, the number of LCPs in the target FP artery positively correlated with max LCBI4mm in the target FP artery (r = 0.671, p = 0.008).

CONCLUSIONS

NIRS-IVUS findings demonstrated the presence of LCPs in nontarget lesions in patients with FP disease. Moreover, the abundance of LCPs in nontarget lesions was similar to that in target lesions in FP disease.

Retrospective analysis on diameters of drug-coated balloons and predilatation balloons in infra-inguinal endovascular treatment (RABBIT study)

This multicenter retrospective study assessed the clinical outcomes of endovascular therapy (EVT) using a drug-coated balloon (DCB) that was larger than the predilatation balloons for femoropopliteal artery lesions. We analyzed 1140 cases with symptomatic peripheral artery disease that underwent EVT with DCB for femoropopliteal lesions between 2017 and 2021. The primary endpoint was procedural failure, defined as a composite of deteriorated dissection and bailout stenting. The secondary endpoints included deteriorated dissection, bailout stenting, restenosis, and target lesion revascularization. We performed propensity score matching to compare the clinical outcomes between EVT with a DCB which was larger than the predilatation balloon (larger DCB) and EVT with a DCB which was not (nonlarger DCB). We assigned 276 cases to the larger DCB group and 864 cases to the nonlarger DCB group. Procedural failure was observed in 75 cases, whereas restenosis occurred in 282 cases during a mean follow-up period of 12.7 ± 9.7 months. Propensity score matching extracted 273 pairs with no intergroup difference in baseline characteristics, except the predilatation balloon size. Procedural failure (9.2% versus 6.1%, P = 0.11), deteriorated dissection and bailout stenting proportion (both P > 0.05), and 1-year rates of freedom from restenosis (82.4% versus 84.1%, P = 0.59) and target lesion revascularization (89.7% versus 90.4%, P = 0.83) showed no significant difference between the larger and nonlarger DCB groups. Irrespective of whether the DCB size was larger than the predilatation balloon, no difference was observed in either procedural or clinical outcomes.

A case of pseudoaneurysm after endovascular therapy with atherectomy and paclitaxel-coated balloon for superficial femoral artery lesion

An 83-year-old woman with claudication in the right lower extremity was referred to our hospital. Since angiography showed severe stenosis with a severely calcified lesion extending from the ostial to proximal part of the right superficial femoral artery (SFA), endovascular therapy (EVT) with the Jetstream™ atherectomy system (Boston Scientific, Marlborough, MA, USA) and paclitaxel-coated balloon (PCB) was performed. Atherectomy was performed using the Jetstream™ atherectomy catheter SC 1.85, followed by an additional atherectomy using the Jetstream™ atherectomy catheter XC 2.1/3.0. Subsequently, angiography and intravascular ultrasound (IVUS) images showed the enlargement of lumen area due to the reduction of calcified plaque, but even some of the healthy media on the side free of calcified plaque had been removed. Next, a PCB dilation was performed, and the final angiography showed adequate dilation. However, the symptoms recurred 9 months after EVT. Angiography revealed an enlarged vessel suggestive of pseudoaneurysm at the ostial part of the right SFA and severe stenosis distal to the enlarged vessel. IVUS images showed a pseudoaneurysm and severe stenosis due to calcified nodules distal to the pseudoaneurysm. This case suggests that pseudoaneurysm is a potential complication of EVT with the Jetstream™ atherectomy system and PCB for SFA lesions.

Learning objective

The Jetstream™ atherectomy system (Boston Scientific, Marlborough, MA, USA) has developed to improve outcomes for femoropopliteal artery lesions with severely calcified lesions in lower extremity arterial disease by removing calcified plaque and improving vascular compliance. Several clinical reports demonstrated durable patency rates and low complication rates after endovascular therapy using the atherectomy device. However, pseudoaneurysm is a potential complication of endovascular therapy with the Jetstream™ atherectomy system.

Predicting residual pressure gradients after balloon angioplasty in patients with femoropopliteal artery lesions

In endovascular therapy (EVT) for femoropopliteal artery (FPA) lesions, studies examining the relationship between lesion morphology and hemodynamic status are limited. The purpose of this study was to investigate FPA lesion characteristics, including imaging findings and their cutoff values that can predict hemodynamic significance after balloon angioplasty. This single-center retrospective study enrolled 50 de novo FPA lesions from 43 patients treated under intravascular ultrasound (IVUS) usage between June 2022 and March 2023. As a physiological parameter, the pressure gradient was measured, and the cutoff value of the residual pressure gradient (RPG) was defined as a systolic pressure > 10 mmHg through the lesions after balloon angioplasty. The pressure gradients were measured using a 0.014-inch wire-guided, rapid exchange-type microcatheter, Navvus II (Acist, Eden Prairie, Minnesota, USA). Predictive risk factors for RPG were analyzed using the random forest (RF) method. The relationship between the variables, RPG, and the cutoff points of each predictor was assessed using the partial dependence plot (PDP) method. RPG was observed in 20% of the lesions after balloon angioplasty. The RF model revealed that the percent diameter stenosis (%DS) and minimum lumen area (MLA) on IVUS assessment were strong predictive factors for RPG after balloon angioplasty. The PDP model revealed that a higher %DS (cutoff 30%) and smaller MLA (cutoff 10 mm2) could predict RPG after balloon angioplasty. Conventional lesion parameters such as %DS and MLA can predict hemodynamic significance during EVT for FPA lesions.

Correlation between physiological assessment and imaging findings during drug-coated balloon treatment for femoropopliteal diseases

BACKGROUND

This prospective cross-sectional study evaluated the correlation between physiological assessment (PA) and minimum lumen area (MLA) by intravascular ultrasound (IVUS) during drug-coated balloon (DCB) treatment for femoropopliteal (FP) diseases.

METHODS

A total of 51 limbs of 44 patients undergoing endovascular treatment with DCB for de novo FP disease were examined from April 2022 to February 2023. PA was conducted at baseline, after balloon dilatation, and after DCB treatment. PA was measured before (pressure ratio; PR) and after vasodilation (peripheral flow fractional flow reserve; pFFR) with the administration of 30 mg papaverine through a guiding catheter. The correlation of PA with percent diameter stenosis (%DS) and MLA was examined, and factors correlated with higher pFFR after balloon dilatation were evaluated in a multivariate analysis.

RESULTS

At baseline, there were correlations between pressure ratio (PR) and %DS (coefficients: 0.641 [p < 0.001]) and between pFFR and %DS (0.666 [p < 0.001]). After balloon dilatation, there was no correlation between PR and %DS (coefficients: 0.33 [p = 0.27]) or between pFFR and %DS (0.41 [p = 0.71]). At baseline, PR and MLA were correlated (coefficients: 0.757 [p < 0.001]) as were pFFR and MLA (0.762 [p < 0.001]). After balloon dilatation, PR and MLA were correlated (coefficients: 0.524 [p < 0.001]) as were pFFR and MLA (0.601 [p < 0.001]). Balloon/EEM ratio, calcification >270°, and chronic total occlusion were associated with pFFR after balloon dilatation.

CONCLUSION

After balloon dilatation, PA was correlated with MLA by IVUS but not with %DS based on angiography.

Impact of Procedural Techniques on Midterm Patency of Fluoropolymer-Based Drug-Eluting Stent Placed in the Femoropopliteal Artery

PURPOSE

To investigate the impact of compliance with recommended procedural techniques on the midterm patency of a fluoropolymer-based drug-eluting stent (FP-DES) in the femoropopliteal artery.

MATERIALS AND METHODS

This retrospective study included 200 femoropopliteal lesions (chronic limb-threatening ischemia, 59%; chronic total occlusion, 41%) in 173 patients (male, 66%; diabetes mellitus, 62%; hemodialysis, 40%) with lower extremity arterial disease who underwent intravascular ultrasound (IVUS)-guided endovascular therapy with FP-DES between January 2016 and July 2021. The primary outcome measure was restenosis, defined as a peak systolic velocity ratio of >2.4 based on the duplex US findings. The association between procedural techniques and incidence of restenosis was investigated using Cox proportional hazards regression models.

RESULTS

The 2-year cumulative incidence of restenosis was 19.5% (SD ± 3.3). Multivariate analysis revealed that noncompliance with recommended procedural techniques, such as plaque burden at the stent edge of <50%, a minimum stent area (MSA) of >12 mm2, and stent placement within the P1 segment, was independently associated with an increased risk of restenosis (hazard ratios [HRs], 3.22, 4.71, and 4.67 and P = .004, P < .001, and P < .001, respectively). The 2-year restenosis risk for procedures performed in compliance with all 3-technical criteria was 8.4% (SD ± 3.4), whereas the risks for those in compliance with 2-technical criteria or 0- or 1-technical criteria were 25.0% (SD ± 6.2) and 48.6% (SD ± 10.4), respectively. HRs relative to 3-technical criteria compliance were 3.79 (P = .007) and 11.85 (P < .001), respectively.

CONCLUSIONS

Noncompliance with recommended procedural techniques, including plaque burden at the stent edge of <50%, MSA of >12 mm2, and stent placement within the P1 segment, was significantly associated with an increased risk of 2-year restenosis after FP-DES implantation in the femoropopliteal artery.

Delayed rupture of peroneal artery pseudoaneurysm following endovascular treatment in a patient with chronic limb-threatening ischemia: A case report

Below-the-knee (BTK) pseudoaneurysms that occur after endovascular therapy (EVT) and result in delayed rupture have rarely been reported. In this report, we present a rare case of an 86-year-old man with chronic limb-threatening ischemia who developed delayed rupture of an idiopathic pseudoaneurysm of the peroneal artery (PA) following EVT. The PA chronic total occlusion (CTO) was successfully crossed using a guidewire via an antegrade approach, however, subintimal crossing was confirmed by intravascular ultrasound. Balloon angioplasty was then performed using an appropriately sized balloon, resulting in successful recanalization of the PA CTO with minor dissection and no complications. Postoperatively, the patient's condition was stable until he suddenly complained of right calf pain 10 days after EVT. Computed tomography revealed a rupture of the PA pseudoaneurysm. Urgent angiography revealed two pseudoaneurysms, one saccular and the other spindle-shaped. The ruptured saccular aneurysm was successfully excluded through coil embolization and stent graft placement. To the best of our knowledge, this is the first reported case of delayed rupture of a BTK pseudoaneurysm following EVT. Balloon angioplasty in the subintimal space can lead to the formation of a pseudoaneurysm and its delayed rupture.

Comparing Predictors Influencing Restenosis Following High-Dose Drug-Coated Balloon Angioplasty and Fluoropolymer-Based Drug-Eluting Stenting in Femoropopliteal Artery Lesions

PURPOSE

Despite widespread use of anti-restenosis devices, drug-coated balloons (DCBs) and drug-eluting stents (DESs), their appropriate use for femoropopliteal (FP) lesions has not been well investigated and the risk factors for restenosis have not been compared. To investigate risk factors associated with restenosis after endovascular therapy using DCB and DES for contemporary FP lesions.

MATERIALS AND METHODS

This single-center, retrospective, observational study evaluated 378 FP lesions in 273 patients treated with DCB (278 lesions in 193 patients) or DES (120 lesions in 106 patients). The DCB used was high-dose DCB (IN.PACT, Admiral. Medtronic, Inc.) and DES was fluoropolymer-based DES (ELUVIA, Boston Scientific). Vessel preparation failure was defined as a residual stenosis of ≥50% and a dissection grade of D or greater on pre-dilatation angiography. The outcome measure was restenosis, and factors associated with restenosis in the DCB and DES groups were assessed using a Cox proportional hazards model.

RESULTS

The 2-year restenosis rate was not significantly different between the DCB and DES groups (29%±4% vs. 24%±5%, p=0.42). Interaction analysis demonstrated that popliteal lesions and plaque burden of ≥50% were restenosis-related factors for DES but not for DCB, whereas vessel preparation failure was a factor for DCB but not for DES (p<0.05). Vessel diameter of <6 mm and nodular calcification were risk factors in both groups (p<0.05).

CONCLUSION

In contemporary FP lesions, smaller vessels and nodular calcification were shared restenosis-related factors for high-dose DCB and fluoropolymer-based DES. Popliteal lesions and plaque burden of ≥50% were restenosis-related factors for fluoropolymer-based DES and vessel preparation failure for high-dose DCB.

CLINICAL IMPACT

Shared and differential restenosis-related factors after endovascular therapy using high-dose drug-coated balloons (DCBs) and fluoropolymer-based drug-eluting stents (DESs) in contemporary femoropopliteal (FP) lesions are unclear. This single-center retrospective study included 378 FP lesions in 273 patients with lower-extremity arterial disease (high-dose DCB, 278 lesions in 193 patients; fluoropolymer-based DES, 120 lesions in 106 patients). Smaller vessels and calcified nodules were shared restenosis-related factors for both high-dose DCB and fluoropolymer-based DES, whereas popliteal lesions and plaque burden of ≥50% were restenosis-related factors for fluoropolymer-based DES and vessel preparation failure for high-dose DCB.

Pathological Analysis of Medial and Intimal Calcification in Lower Extremity Artery Disease: Impact of Hemodialysis

Background

The prevalence and degree of lower extremity artery disease in hemodialysis (HD) patients is higher than in the general population. However, the pathological features have not yet been evaluated.

Objectives

The aim of the study was: 1) to compare lesion characteristics of lower extremity artery disease in HD vs non-HD patients; and 2) to determine factors associated with severe medial calcification.

Methods

Seventy-seven lower limb arteries were assessed from 36 patients (median age 77 years; 23 men; 21 HD and 15 non-HD) who underwent autopsy or lower limb amputation. Arteries were serially cut at 3- to 4-mm intervals creating 2,319 histological sections. Morphometric analysis and calcification measurements were performed using ZEN software. Calcification with a circumferential angle (arc) ≥180° was defined as severe calcification. Multivariable logistic regression was used to identify risk factors for severe medial calcification.

Results

The degree of the medial calcification arc was significantly higher in the HD group compared to the non-HD group (P < 0.0001). In the multivariable analysis, HD was associated with severe medial calcification in below-the-knee lesions (OR: 17.1; P = 0.02). The degree of intimal calcification in above-the-knee lesions was also significantly higher in HD patients with a higher prevalence of advanced atherosclerotic plaque (P = 0.02). The prevalence of severe bone formation was more common in the HD patients (P = 0.01).

Conclusions

Hemodialysis patients demonstrated a higher degree of medial and intimal calcification compared with non-HD patients. The difference was more prominent in the medial calcification of below-the-knee lesions.

Poor Below Knee Runoff Impacts Femoropopliteal Stent Failure and Fluoropolymer Antithrombotic Effect in Healthy Swine Model

OBJECTIVE

Poor below knee (BTK) runoff is a predictor of stent failure after endovascular femoropopliteal artery treatment; however, lack of pathological evaluation has prevented characterisation of stent failure. The study aimed to investigate the impact of poor BTK runoff and the antithrombotic effect of the polymer of fluoropolymer coated paclitaxel eluting stents (FP-PESs) in a healthy swine femoropopliteal artery model.

METHODS

FP-PESs and bare metal stents (BMSs) and FP-PES and polymer free paclitaxel coated stents (PF-PCSs) were implanted in the bilateral femoral arteries of healthy swine (n = 6, respectively) following coil embolisation in both tibial arteries to induce poor BTK runoff. Histological assessment and intravascular imaging device evaluation were performed at one month. The Japanese Association for Laboratory Animal Science approved the study protocol (reference number: IVT22-90).

RESULTS

Optical coherence tomography showed significantly lower percent area stenosis in FP-PES compared with BMS (37.3%, [interquartile range (IQR), 25.6 - 54.3] % vs. 92.5% [IQR, 75.5 - 96.1] %, respectively, p = .031), and PF-PCS (8.3% [IQR, 4.5 - 27.0] % vs. 31.2% [IQR, 23.3 - 52.2] %, respectively, p = .031). Histopathological evaluation demonstrated that thin fibrin attachment without re-stenosis was the most dominant neointimal tissue characteristic in FP-PES. On the other hand, neointimal tissue characteristics with significant restenosis of BMS and PF-PCS were mainly organising or organised thrombus.

CONCLUSION

Organising and or organised thrombus attachment due to poor BTK runoff was the main cause of in stent restenosis of the swine femoral artery. FP-PES demonstrated the least percent area stenosis, suggesting the importance of the antithrombotic effect of polymer.

Impact of postprocedural minimum lumen area on clinical outcome after femoropopliteal drug-eluting stent implantation

INTRODUCTION

Although favorable results of fluoropolymer-based drug-eluting stent (FP-DES) treatment for femoropopliteal lesions have been reported, it is unclear whether minimal lumen area (MLA) after FP-DES implantation affects clinical outcomes. This study aimed to reveal the association between intravascular ultrasound (IVUS)-evaluated MLA and the 1-year risk of restenosis and aneurysmal degeneration after FP-DES implantation for femoropopliteal lesions.

METHODS

A subanalysis of the CAPSICUM (Contemporary outcomes After Paclitaxel-eluting peripheral Stent implantation for symptomatic lower limb IsChemia with sUperficial feMoral or proximal popliteal lesion) study analyzed 718 limbs in 686 patients with available IVUS-evaluated MLA data. The association of MLA with the 1-year risk of restenosis and aneurysmal degeneration was analyzed using the generalized propensity score method.

RESULTS

The 1-year incidence rate of restenosis was estimated to be 8.8% (95% CI, 6.1% to 12.5%) for the upper quartile of MLA (21.1 mm2) versus 14.3% (95% CI, 10.7% to 18.7%) for the lower quartile of MLA (15.2 mm2), with an odds ratio of 0.58 (95% CI, 0.36 to 0.93; p = 0.024), whereas the 1-year incidence rate of aneurysmal degeneration was 23.8% (95% CI, 19.5% to 28.8%) for the upper quartile versus 16.8% (95% CI, 12.6% to 22.0%) for the lower quartile, with an odds ratio of 1.55 (95% CI, 1.04 to 2.32; p = 0.031).

CONCLUSION

A large MLA after FP-DES implantation for femoropopliteal lesions was associated with decreased restenosis risk but increased aneurysmal degeneration risk. These findings suggest that MLA is a valuable predictor of clinical outcomes.

Clinical outcome of endovascular therapy using a VIABAHN VBX-covered stent for complex aortoiliac artery disease: the AVOCADO II study

Clinical trials have demonstrated the efficacy of a balloon-expandable covered stent (CS) for aortoiliac occlusive disease (AIOD). However, the real-world clinical outcomes and the underlying factors remain unclear. We assessed the clinical outcomes and factors associated with primary patency after implantation of a balloon-expandable CS for patients with complex AIOD. This prospective multicenter observational study enrolled 149 consecutive patients undergoing VIABAHN® VBX-CS (W.L. Gore & Associates, Flagstaff, AZ) implantation for complex AIOD (age, 74 ± 9 years; male, 74%; diabetes mellitus, 46%; renal failure on dialysis, 23%; chronic limb-threatening ischemia, 26%). The primary study endpoint was 1-year primary patency, and the secondary endpoints were procedural complications, freedom from occlusion, clinical-driven target lesion revascularization (CD-TLR), and surgical revision at 1 year. Risk factors for restenosis were explored using random survival forest analysis. The median follow-up period was 13.1 months (interquartile range 9.7-14.0 months). Procedural complications were observed in 6.7% of the patients. The 1-year primary patency was 94.8% (95% confidence interval 91.0-98.6%), while the 1-year freedom rate from occlusion, CD-TLR, and surgical revision rates were 96.5% (93.5-99.5%), 94.7% (90.9-98.6%), and 97.8% (95.4-100%), respectively. The presence of chronic total occlusion, aortic bifurcation lesion, the number of disease regions, and TASC-II classification was significantly associated with the restenosis risk. In contrast, the calcification severity, IVUS use, IVUS parameters were not associated with restenosis risk. We observed excellent 1-year real-world outcomes after implantation of a balloon-expandable CS for complex AIOD; only a few perioperative complications occurred.

Impact of Postoperative Lumen Gain on the Reduction of Restenosis Risk after Endovascular Treatment using Drug-coated Balloon for Femoropopliteal Lesions Assessed by Intravascular Ultrasound

AIM

This study aimed to reveal whether a larger postprocedural minimum lumen area (MLA) would reduce restenosis risk after endovascular therapy (EVT) using drug-coated balloons (DCBs) in femoropopliteal (FP) lesions.

METHODS

This retrospective, nonrandomized, single-arm, and multicenter registry analyzed patients with FP lesions undergoing intravascular ultrasound (IVUS)-guided EVT with DCB between 2017 and 2021. The primary outcome was restenosis 1 year after EVT. The association between IVUS-based MLA and restenosis risk was investigated using a generalized propensity score (GPS) method to address imbalance of baseline covariates. The dose-response function of IVUS-measured MLA for restenosis risk was developed using the GPS-adjusted Cox proportional hazards regression model.

RESULTS

This study enrolled consecutive 489 patients with 595 lesions undergoing DCB treatment. The median MLA (interquartile range) was 13.20 (9.90-16.91) mm2. Kaplan-Meier estimates showed that freedom from restenosis was 84.4% at 1 year. The GPS-adjusted dose-response function showed that MLA was inversely associated with restenosis risk. The upper limit of 95% confidence interval (CI) of the slope was lower than 0 between 10.6 and 17.0 mm2 of MLAs. The 1-year cumulative incidence of restenosis was estimated to be 9.8% (95% CI, 5.8%-13.7%) for the 3rd quartile of MLA (16.91 mm2) versus 18.5% (12.3%-24.1%) for the 1st quartile (9.90 mm2), with a hazard ratio of 0.51 (95% CI, 0.39-0.67; p＜0.001).

CONCLUSIONS

The present GPS analysis suggested that larger IVUS-measured MLA might be associated with lower risk of 1-year restenosis after DCB treatment for FP lesions.

Predictors of recurrence based on intravascular ultrasound findings after Eluvia placement in symptomatic peripheral arterial disease: A retrospective study

Background and Aims

Polymer-coated drug-eluting stents (Eluvia) have shown favorable clinical outcomes in real-world registries. There are no reports on recurrent predictors after Eluvia placement based on intravascular ultrasound (IVUS) findings.

Methods

We analyzed clinical data from the ASIGARU PAD registry, a retrospective, multicenter, observational study that enrolled patients who underwent endovascular therapy for superficial femoral and proximal popliteal arteries lesions using Eluvia or drug-coated balloon. The primary outcome was the identification of recurrent predictors, including IVUS parameters at 12 months. The rate of target lesion recurrence was also assessed.

Results

IVUS images were obtained in 54 of 65 cases. Seven recurrent cases (13.0%) were observed within 12 months. The random survival forest method presented eight predictive variables of recurrence: Clinical Frailty Scale (CFS), distal stent edge area, distal plaque burden, age, sex, distal external elastic membrane (EEM) area, minimum stent area (MSA), and distal lumen area. Furthermore, the partial dependence plot showed that frailty (CFS ≥ 6), smaller distal stent edge area, higher and lower distal plaque burden, older and younger age, female sex, smaller distal EEM area, smaller MSA, and smaller and larger distal lumen area predicted recurrence after Eluvia placement within 12 months.

Conclusion

CFS, distal stent edge area, distal plaque burden, age, sex, distal EEM area, MSA, and distal lumen area were significant recurrent predictors after Eluvia placement.

Impact of plaque and luminal morphology in balloon angioplasty of the femoropopliteal artery: an intravascular ultrasound analysis

Objective

To assess the effect of plaque and luminal morphologies in balloon angioplasty of femoropopliteal lesions using intravascular ultrasound (IVUS).

Methods

This retrospective, observational study analyzed 836 cross-sectional images using IVUS, from 35 femoropopliteal arteries of patients who underwent endovascular treatment between September 2020 and February 2022. Pre- and post-balloon angioplasty images were matched per 5 mm. Post-balloon angioplasty images were grouped into successful (n = 345) and unsuccessful (n = 491) groups. Plaque and luminal morphologies (such as severity of calcification, vascular remodeling, and plaque eccentricity) were extracted before the balloon angioplasty procedure to identify the predictors of unsuccessful balloon angioplasty. Additionally, 103 images with severe dissection were analyzed using IVUS and angiography.

Results

In univariate analyses, the predictive factors for unsuccessful balloon angioplasty were vascular remodeling (p < .001), plaque burden (p < .001), lumen eccentricity (p < .001), and balloon/vessel ratio (p = .01). Predictive factors for severe dissections were the guidewire route (p < .001) and balloon/vessel ratio (p = .04). In multivariate analysis, the predictive factors for unsuccessful balloon angioplasty included lumen eccentricity (odds ratio [OR]: 3.99, 95% confidence interval [CI]: 1.28-12.68, p = .02) and plaque burden (OR: 1.03, 95% CI: 1.02-1.04; p < .001). For severe dissections, the independent risk factor was an eccentric guidewire route (OR: 2.10, 95% CI: 1.22-3.65, p = .01).

Conclusion

High plaque burden and luminal eccentricity were risk factors for failed femoropopliteal artery balloon angioplasty. Additionally, eccentric guidewire routes predicted severe dissection.

Multicenter, retrospective registry of isolated atherosclerotic popliteal arteries treated with endovascular revascularization

Isolated atherosclerotic popliteal lesions (IAPLs) have been considered challenging. This study aimed to investigate the efficacy of endovascular therapy (EVT) using the newer devices for IAPLs. This retrospective multicenter registry analyzed patients with lower extremity artery disease having IAPLs who underwent EVT using the newer devices between 2018 and 2021. The primary outcome was primary patency 1 year after EVT. A total of 392 consecutive patients undergoing EVT for IAPLs were enrolled. The Kaplan-Meier analysis showed that the primary patency and the freedom from target lesion revascularization were 80.9% and 87.8% 1 year after EVT, respectively. The multivariate Cox proportional hazards regression analysis showed that the clinical features that were independently associated with restenosis risk were drug-coated balloon (DCB) use for younger age (< 75 years old; adjusted hazard ratio, 3.08 [95% confidence interval 1.08-8.74]; P = 0.035), non-ambulatory status (2.74 [95% confidence interval 1.56-4.81]; P < 0.001), cilostazol use (0.51 [95% confidence interval 0.29-0.88]; P = 0.015), severe calcification (1.86 [95% confidence interval 1.18-2.94]; P = 0.007), and small external elastic membrane (EEM) area measured by intravascular ultrasound (IVUS) (< 30 mm²) (2.07 [95% confidence interval 1.19-3.60]; P = 0.010). From the univariate analysis, among patients treated with DCB, younger patients (n = 141) were associated with more comorbidities including smoking (P < 0.001), diabetes mellitus (P < 0.001), end-stage renal disease (P < 0.001), history of revascularization (P = 0.046) and small EEM area (P = 0.036), compared to older patients (n = 140). Moreover, smaller post-procedural minimum lumen area measured by IVUS after DCB dilatation was observed in younger patients (12 ± 4 vs. 14 ± 4 mm², P = 0.033). This retrospective study demonstrated that the current EVT provided an acceptable 1-year primary patency rate in patients with IAPLs. The primary patency was lower following DCB in younger patients, likely due to the higher rates of comorbidities in this patient population.

Histological evaluation of vascular changes after excimer laser angioplasty for neointimal formation after bare-metal stent implantation in rabbit iliac arteries

BACKGROUND

Excimer laser is used to treat coronary artery disease, especially in case of lesions with thrombus and in-stent restenosis (ISR). However, there are no in vivo preclinical studies that have evaluated the pathological reactions of the vessel wall after excimer laser ablation.

METHODS

Bare-metal stents were placed in the external iliac arteries of six healthy rabbits. Twenty-eight days later, excimer laser ablation was performed with low-power (45 (fluency)/25 (rate)) in one side, and high-power (60/40) in the opposite side, followed by optical coherence tomography (OCT) evaluation. Rabbits were sacrificed 15 min after the procedure, and histological assessment was performed.

RESULTS

Morphometry analysis of OCT showed similar stent and lumen size between low-power and high-power group. Histological evaluation suggested endothelial cell loss, fibrin deposition, and tissue loss. The low-power group showed significantly less pathological changes compared with the high-power group: angle of endothelial cell loss, 32.4° vs. 191.7° (interquartile range, 8.8°-131.7° vs. 125.7°-279.5°; p < 0.01); fibrin deposition, 1.1° vs. 59.6° (0.0°-70.4° vs. 31.4°-178.4°; p = 0.03); and tissue loss 0.0° vs. 18.2° (0.0°-8.7° vs. 0.0°-42.7°; p = 0.03).

CONCLUSIONS

The pathological changes in neointima were more prominent after high-power excimer laser ablation than after low-power excimer laser. To improve safety in clinical practice, understanding the pathological changes of tissues after excimer laser in lesions with ISR is essential.

Success rate of endovascular recanalization for femoropopliteal artery total occlusion using the wingman catheter system

Chronic total occlusion (CTO) in the femoropopliteal artery is challenging to treat. The Wingman catheter system is a novel device for CTO penetration with a nitinol/stainless steel beveled tip. There is a lack of real-world clinical data indicating the success rate. We evaluated the efficacy of the Wingman system. This was a single-center retrospective study. We enrolled 27 consecutives patients who underwent treatment for femoropopliteal CTO using the Wingman system in 2021. The primary outcome was success of CTO-crossing and secondary outcomes were success of the procedure, Wingman-related complications, and predictors for success of Wingman crossing. The mean age of the study population was 76 years and the mean CTO length was 122 mm. The success rate of Wingman crossing was 40.7% and the overall procedure success rate was 100%. Only one case of embolism and one of perforation associated with the Wingman procedure were seen; both were successfully recovered. Univariate analysis revealed in-stent occlusion and non-severe calcification to be factors associated with success (16.7% vs 0%, p = 0.012 and 12.5% vs 50.0%, p = 0.036, respectively). These real-world data of the Wingman system demonstrate it to be a safe and one of option for treating femoropopliteal CTO.

Angioscopic Evaluation of Vascular Response After Fluoropolymer-Based Drug-Eluting Stent Implantation for Femoropopliteal Artery Lesions

BACKGROUND

Although favorable clinical outcomes have been demonstrated for fluoropolymer-based paclitaxel-eluting stents (FP-DES) in the treatment of femoropopliteal lesions, the vascular response after implantation has not been systematically studied through intravascular imaging.

METHODS AND RESULTS

We angioscopically compared FP-DES: 24 in the early phase (mean [±SD] 3±1 months), 26 in the middle phase (12±3 months), and 20 in the late phase (≥18 months) after implantation. The dominant neointimal coverage grade, heterogeneity of neointimal coverage grade, and thrombus adhesion in the stent segment were evaluated. Neointimal coverage was graded as follows: Grade 0, stent struts exposed; Grade 1, struts bulging into the lumen, although covered; Grade 2, struts embedded in the neointima, but visible; Grade 3, struts fully embedded and invisible. Dominant neointimal coverage and heterogeneity grades were significantly higher in the middle and late phases than in the early phase (all P<0.05), but did not differ significantly between the middle and late phases. The incidence of thrombus adhesion was recorded for all stents in each of the 3 different phases.

CONCLUSIONS

The middle and late phases after FP-DES implantation were associated with significantly higher dominant neointimal coverage and heterogeneity grades than the early phase. However, thrombus adhesion was observed in all phases after FP-DES implantation. Arterial healing may not be completed even in the late phase after FP-DES implantation.

Intravascular ultrasound-based decision tree model for the optimal endovascular treatment strategy selection of femoropopliteal artery disease-results from the ONION Study

BACKGROUND

The role of catheter-based imaging in peripheral interventions for lower extremity artery disease (LEAD) has increased with percutaneous interventions. To clarify the relation between intravascular ultrasound (IVUS) information and procedure selection strategy for endovascular treatment therapy (EVT) of the femoropopliteal artery in the real-world clinical settings wherein new endovascular technologies (NETs), including drug-coated balloon (DCB), drug-eluting stent (DES), and covered stent-graft (CS). Our retrospective multicenter analysis examined symptomatic 970 patients treated by EVT for de novo femoropopliteal lesions with IVUS guidance. The decision tree analysis was performed retrospectively to determine the association of IVUS and angiography parameters with the strategy selection of endovascular procedures. We divided the study population according to the developed tree, and identified the most popular strategy selection in each subgroup. We finally examined whether the restenosis risk would be different among respective subgroups of the tree.

RESULTS

During the study periods, plain old balloon angioplasty, DCB, and bare nitinol stent were most frequently selected (25.3%, 23.9%, and 23.8%, respectively). The drug-eluting stent (DES), covered stent (CS), and spot stent strategies were used in 7.3%, 11.5%, and 8.1%. NETs had the lowest restenosis risk in the overall population. The decision tree had a depth of six branches and divided the patients into 11 subgroups by IVUS and angiography parameters. The restenosis rate was similarly low among these 11 subgroups when the most popular NET in each subgroup was selected (P = 0.94).

CONCLUSIONS

The use of IVUS data along with angiography data would standardize the selection of endovascular procedures and can improve patency outcomes if NETs are used properly.