Impact of Plaque Calcification and Stent Oversizing on Clinical Outcomes of Atherosclerotic Femoropopliteal Arterial Occlusive Disease Following Stent Angioplasty

Impact of Calcification on the Outcomes of Femoropopliteal Artery Endovascular Treatment Using a Polymer Coated Drug-Eluting Stent

PURPOSE

The aim of this study was to analyze the impact of calcification on the 12 and 24 months outcomes of the Eluvia™ (Boston Scientific®) drug-eluting stent (DES) for femoropopliteal occlusive disease using three different calcium scoring systems.

MATERIAL AND METHODS

A single-center, retrospective cohort-study (March-2016 to December-2018) of patients treated with the Eluvia™ DES for femoropopliteal atherosclerosis was performed. Outcomes included primary and secondary patency rates and freedom from target lesion revascularization (FTLR) and were analyzed by comparing the impact of calcium burden according to the following calcium scores: Peripheral Arterial Calcium Scoring System (PACSS) score, number of vessel quadrants affected (0-4) and calcification score per Peripheral Academic Research Consortium (PARC) definitions.

RESULTS

In total, 111 Patients were included (mean age: 71.2 ± 7.9; 64% male). Most patients presented with Rutherford class 3 (79.9%), followed by class 5 (12.7%), class 4 (10%) and class 6 (6.4%). The mean lesion length was 197.6 ± 108.5 mm and 74.3% of patients had chronic total occlusions. There were no differences in primary patency between the calcification scores at 12 months (PACSS, LogRank = 0.28; quadrants, LogRank = 0.29; PARC, LogRank = 0.42) and 24 months (PACSS, LogRank = 0.13; quadrants, LogRank = 0.42; PARC, LogRank = 0.13). FTLR was significantly lower at 12 months in patients with calcification affecting 3 or 4 quadrants (LogRank = 0.022) but not at 24 months (LogRank = 0.36).

CONCLUSIONS

In this study, the Eluvia™ DES showed promising performance in calcified disease and the analysis according to the quadrant model predicted an increased risk for TLR at 12 months.

Post-angioplasty remodeling of coronary arteries investigated via a chemo-mechano-biological in silico model

This work presents the application of a chemo-mechano-biological constitutive model of soft tissues for describing tissue inflammatory response to damage in collagen constituents. The material model is implemented into a nonlinear finite element formulation to follow up a coronary standard balloon angioplasty for one year. Numerical results, compared with available in vivo clinical data, show that the model reproduces the temporal dynamics of vessel remodeling associated with subintimal damage. Such dynamics are bimodular, being characterized by an early tissue resorption and lumen enlargement, followed by late tissue growth and vessel constriction. Applicability of the modeling framework in retrospective studies is demonstrated, and future extension towards prospective applications is discussed.

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.

Peripheral arterial disease treatment planning using noninvasive and invasive imaging methods

With the growing prevalence and mortality of peripheral arterial disease, preoperative assessment, risk stratification, and determining the correct indication for endovascular and open surgical procedures are essential for therapeutic decision-making. The effectiveness of interventional procedures is significantly influenced by the plaque composition and calcification pattern. Therefore, the identification of patients for whom endovascular treatment is the most appropriate therapeutic solution often remains a challenge. The most commonly used imaging techniques have their own limitations and do not provide findings detailed enough for specific, personalized treatment planning. Using state-of-the-art noninvasive and invasive imaging modalities, it is now possible to obtain a view, not only of the complex vascular anatomy and plaque burden of the lower extremity arterial system, but also of complex plaque structures and various pathologic calcium distribution patterns. In the future, as these latest advancements in diagnostic methods become more widespread, we will be able to obtain more accurate views of the plaque structure and anatomic complexity to guide optimal treatment planning and device selection. We reviewed the implications of the most recent invasive and noninvasive lower extremity imaging techniques and future directions.

Dichotomous grouping of peripheral arterial calcification grades: A practical predictor of outcome after endovascular therapy in peripheral arterial disease

BACKGROUND

There is a general agreement that arterial calcification affects the results of endovascular therapy for peripheral arterial disease (PAD). In addition to lacking evidence for their impact, existing calcification scores are complex, and not practical in everyday decision making. The global limb anatomic staging system (GLASS) adopted dichotomous grouping of calcification grades.

OBJECTIVE

In this study we aim to investigate the impact of peripheral arterial calcification scoring after dichotomous grouping on midterm outcomes following endovascular therapy for PAD.

METHODS

This prospective study included all consecutive patients with PAD indicated for endovascular therapy procedure who presented to our tertiary referral center in the period between October 2020 and October 2021. Patients were grouped into Group A (n = 40): with no-to mild calcification (PACSS grade 0,1 and 2), and Group B (n = 53): with severe calcification (PACSS grades 3 and 4). Primary endpoints included technical success rate, primary patency rates, and major adverse limb events rate (MALE) during 2 years of follow-up.

RESULTS

The mean age of the studied cases (n = 93) was 59.31 ± 6.46 years (range 50-75). 70 patients (75.3%) were males, and 23 (24.7%) were females. There was no statistically significant difference between the two groups regarding technical success rate (97.5% in group A versus 94.33% in Group B, p = .457). The Primary patency rate after 1 year was lower in group B (74%) compared to group A (89.7%), but this difference was not statistically significant (p = .059). However, the 2-year primary patency rate was significantly lower in group B compared to group A (64% versus 84.6% respectively, p = .034). MALE rate after 2 years was significantly higher in group B (28%) as compared to group A (10.4%), P = .048. Studying suspected risk factors revealed that severe calcification was more common in patients with ischemic heart disease (34%) and chronic kidney disease (11%), P= .003 and .002 respectively. Logistic regression analysis showed that patients suffered from IHD and those with length of lesion ≥ 5 cm are about five times more likely to have severe calcification compared to their counterparts (OR = 4.875, 95%CI = 1.293-18.383, p = .019, and OR = 4.513, 95% CI = 11.138-17.893, p = .032), respectively.

CONCLUSION

The presence of severe calcification is associated with significantly lower midterm primary patency rates and higher rate of major adverse limb events after endovascular intervention for lower limb denovo arterial lesions.

Calcification is a risk factor for intracranial in-stent restenosis: an optical coherence tomography study

BACKGROUND

The frequent occurrence of calcification in intracranial artery stenosis increases the risk of ischemic stroke. In previous cases, we have observed a possible relationship between calcification and intracranial in-stent restenosis (ISR) using optical coherence tomography (OCT). Therefore, our study aimed to demonstrate the relationship between intracranial calcification and ISR with a larger sample size.

METHODS

For our study patients who underwent OCT for intracranial artery stenosis before stenting were included from May 2020 to October 2022. Follow-up assessments were performed using transcranial color-coded duplex (TCCD) sonography ultrasonography to detect cases of ISR.

RESULTS

We recruited 54 patients, 15 of them were excluded as they did not meet the study criteria. Our study included 39 patients, of whom 21 had calcification, and 18 did not. The results of our study revealed a significant association between calcification and intracranial ISR (9 (42.86) vs 2 (11.11), p=0.0375). Notably, patients with macrocalcification were more likely to undergo ISR than patients with spotty calcification (77.78% vs 22.22%, p=0.03).

CONCLUSION

OCT imaging demonstrates that calcification is an essential risk factor for intracranial ISR. These findings have important implications for individualized treatment. They provide valuable insights for optimizing stent design and exploring potential mechanisms of intracranial ISR.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT05550077.

Multi-Modality Imaging of Atheromatous Plaques in Peripheral Arterial Disease: Integrating Molecular and Imaging Markers

Peripheral artery disease (PAD) is a common and debilitating condition characterized by the narrowing of the limb arteries, primarily due to atherosclerosis. Non-invasive multi-modality imaging approaches using computed tomography (CT), magnetic resonance imaging (MRI), and nuclear imaging have emerged as valuable tools for assessing PAD atheromatous plaques and vessel walls. This review provides an overview of these different imaging techniques, their advantages, limitations, and recent advancements. In addition, this review highlights the importance of molecular markers, including those related to inflammation, endothelial dysfunction, and oxidative stress, in PAD pathophysiology. The potential of integrating molecular and imaging markers for an improved understanding of PAD is also discussed. Despite the promise of this integrative approach, there remain several challenges, including technical limitations in imaging modalities and the need for novel molecular marker discovery and validation. Addressing these challenges and embracing future directions in the field will be essential for maximizing the potential of molecular and imaging markers for improving PAD patient outcomes.

Protocol of the evolution study: A prospective, multicenter, observational study evaluating the effect and health economics of endovascular treatment in patients with moderate and severe calcification of femoropopliteal artery

Objectives

Peripheral artery disease with calcification is extremely prevalent in the elderly. Due to the calcification, it requires a different clinical approach than the more common arteriosclerosis obliterans of the lower extremity. The introduction of novel technologies such as the drug-coated balloon, directional atherectomy, supera and drug-eluting stent has improved the prognosis of these patients. This study will contribute to the development of higher-quality evidence-based medicine for clinical treatment by assessing the quality of life (QOL), clinical treatment effect, and health economics of patients with calcification.

Method and analysis

The Evolution study is designed as a prospective, multicenter, observational, real-world study. From January 2021 to December 2022, 600 patients with moderate to severe femoropopliteal artery calcification will be recruited from ten locations in China. After discharge, information on demographics, disease history, procedure details, imaging findings, and follow-up will be collected. Patients will undergo follow-up at 1, 6, 12, 18, and 24 months after operation. Technical success rate, vascular quality of life questionnaire, primary patency rate of the target lesion, clinically driven target lesion revascularization rate (CD-TLR), and health economics evaluation are all included as outcome measures.

Conclusions

The Evolution study helps to investigate the clinical and financial results of various endovascular therapy modalities for patients with moderate and severe femoropopliteal artery calcification. These actual facts may help to harmonize therapy recommendations for peripheral artery disease.

Clinical trial registration

The study protocol was registered at www.clinicaltrials.gov (registration number: NCT04716361).

Superficial femoral artery calcification segmentation and detection in CT angiography using convolutional neural network

PURPOSE

Calcification detection and segmentation in CT angiography (CTA) is the basis of preoperative calcification assessment and treatment determination in endovascular interventional surgery for lower-extremity atherosclerotic occlusion disease. However, the complex calcification-lumen contrast and difficult-to-locate occluded superficial femoral artery (SFA) make it challenging. This paper proposes a fast and accurate method without artery extraction to segment and detect SFA calcification in CTA using a convolutional neural network.

METHOD

The thigh region containing the target SFA is first automatically extracted based on the human anatomical position. Then, 3D Unet with a large receptive field is used to segment calcifications in image patches with a large field of view. The lumen label is introduced and a calcification-lumen contrast data augmentation method is developed to improve the segmentation performance on images with varying calcification-lumen contrast. Finally, false-positive errors far from the SFA are eliminated based on the SFA centerline estimated from the segmentation results.

RESULTS

Five-fold cross validation experiments were conducted on a local dataset of CTA images containing 128 SFAs. The average Dice scores of calcification segmentation on the entire, occluded and non-occluded arteries achieved 89.12%, 92.98% and 88.96%, respectively. The average recall and precision of calcification detection on each slice were 93.50% and 91.51%, respectively. The total processing time was about 2 min.

CONCLUSIONS

This paper proposes a CNN-based method to segment and detect SFA calcification in CTA without artery extraction for varying calcification-lumen intensity contrast and arterial occlusion situations. The work can be used to improve clinical calcification analysis.

Vascular Pathology and Impact of Stent Eccentricity for Stent Restenosis in Femoropopliteal Endovascular Therapy

PURPOSE

To explore the clinical features associated with stent eccentricity and reveal the impact of stent eccentricity on 1-year restenosis risk after femoropopliteal stent implantation for symptomatic atherosclerotic peripheral artery disease (PAD).

MATERIALS AND METHODS

The effect of stent asymmetry expansion immediately after treatment on long-term patency has not been fully investigated. We used the clinical database of a multicenter prospective study registering 2,018 limbs of 1,766 patients in whom intravascular ultrasound (IVUS)-supported femoropopliteal endovascular therapy (EVT) for symptomatic atherosclerotic PAD was planned from November 2015 to June 2017. We included 1,233 limbs of 1,088 patients implanted with either a bare nitinol stent, drug-eluting stent (DES), or stent graft, and administered two or more antithrombotic drugs. Stent eccentricity was evaluated using IVUS calculated as ((maximum diameter)/(minimum diameter) - 1) at the cross-section segment with the lowest lumen area after stent implantation.

RESULTS

Chronic total occlusion and bilateral arterial calcification (peripheral artery calcification scoring system grades 3 and 4) were positively associated with stent eccentricity, whereas renal failure on dialysis, DES, and stent graft use were negatively associated with stent eccentricity (all p<0.05). Stent eccentricity was associated with an increased risk of 1-year restenosis (odds ratio (OR) 1.18, 95% confidence interval (CI) 1.01-1.37; p=0.034). However, after adjustment for the lesion severity and implanted stent types, the association was no longer significant (OR 1.07, 95% CI 0.91-1.24; p=0.43).

CONCLUSION

Stent eccentricity was not significantly associated with 1-year restenosis risk after femoropopliteal EVT.

A systematic review and meta-analysis of Supera interwoven nitinol stents for the treatment of infrainguinal peripheral arterial disease

INTRODUCTION

Stenting of infrainguinal lesions can be rather challenging due to the mechanical stress applied on the arteries during motion. We assessed the short-term and mid-term safety and efficacy of Supera interwoven nitinol stent for the treatment of infrainguinal arterial disease.

EVIDENCE ACQUISITION

We conducted a systematic review for articles published from December 2011 up to May 2021 regarding studies assessing the safety and efficacy of Supera interwoven nitinol stents for the treatment of infra-inguinal peripheral arterial disease. Studies that involved synchronous application of the Supera stent and drug delivering devices, or any alternative endoprosthesis were excluded. Pooled Kaplan-Meier survival curves and smoothed hazard estimates were generated. Data were meta-analyzed using a random effects model. Primary endpoints included primary patency and freedom from clinically driven target lesion revascularization (TRL). Secondary endpoints included technical success and major amputation at 1 year post intervention.

EVIDENCE SYNTHESIS

Seventeen studies with 2015 patients (65.3% males) and a mean lesion length of 137.2 mm were included. Of the total treated lesions, 44.9% involved femoropopliteal artery and 37.4% the popliteal artery. Chronic total occlusions made up 49% of the treated lesions. There were no stent fractures reported. The pooled technical success rate is 99.84% (95% CI: 99.26-100). Pooled major amputation rate at 1 year is 1.48% (95% CI: 0.47-2.87). Pooled primary patency and freedom from TLR rates at 1 year are 83.5% (95% CI: 80.24-86.54) and 90.32% (95% CI: 88.75-91.79), respectively. Pooling of individual patient data produced primary patency and freedom from TLR rates of 84.48% (95% CI: 82.66-86.11) and 90.81% (95% CI: 88.64-92.58) respectively. According to the smoothed hazard ratio estimate the risk for losing primary patency peaked between 4 and 5 months while the risk for TLR peaked between 7 and 8 months after the intervention.

CONCLUSIONS

This review and meta-analysis indicated the safety and efficacy of Supera stents for the treatment of challenging infrainguinal lesions in the short-term and mid-term periods, with acceptable primary patency and freedom from TLR rates. Clinicians should be aware that between 4 and 5 months patients face a higher risk for event occurrence.

Personalised nitinol stent for focal plaques: Design and evaluation

The purpose of this study is to develop personalised nitinol stents for arteries with one and two opposite focal plaques. Novel designs are evaluated through comparison with a commercial stent design, in terms of lumen gain and shape as well as stress levels in the media layer after stenting.

METHODS

Personalised stents are developed for arteries with one and two opposite focal plaques, based on medical imaging of patients and computer simulations. In silico analysis is then carried out for assessment of stent performance in the diseased arteries.

RESULTS

Personalised designs significantly increase the lumen gain, reduce the stresses in the media layer, and improve the lumen shape compared to the commercial nitinol stent.

CONCLUSION

The personalised designs show outstanding performance compared to the commercial stent.

SIGNIFICANCE

This pilot study proves that personalised nitinol stents are able to deliver desirable treatment outcomes.

Selenium-Containing Protein From Selenium-Enriched Spirulina platensis Attenuates High Glucose-Induced Calcification of MOVAS Cells by Inhibiting ROS-Mediated DNA Damage and Regulating MAPK and PI3K/AKT Pathways

Hyperglycemia is the main feature of diabetes and may increase the risk of vascular calcification (VC), which is an independent predictor for cardiovascular and cerebrovascular diseases (CCD). Selenium (Se) may decrease the risk of CCD, and previous studies confirmed that Se-containing protein from Se-enriched Spirulina platensis (Se-SP) exhibited novel antioxidant potential. However, the effect of Se-SP against VC has been not investigated. Herein, the protective effect and underlying mechanism of Se-SP against high glucose-induced calcification in mouse aortic vascular smooth muscle cells (MOVAS) were explored. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) results showed time-dependent uptake of Se-SP in MOVAS cells, which significantly inhibited high glucose-induced abnormal proliferation. Se-SP co-treatment also effectively attenuated high glucose-induced calcification of MOVAS cells, followed by decreased activity and expression of alkaline phosphatase (ALP). Further investigation revealed that Se-SP markedly prevented reactive oxygen species (ROS)-mediated DNA damage in glucose-treated MOVAS cells. ROS inhibition by glutathione (GSH) effectively inhibited high glucose-induced calcification, indicating that Se-SP could act as ROS inhibitor to inhibit high glucose-induced DNA damage and calcification. Moreover, Se-SP dramatically attenuated high glucose-induced dysfunction of mitogen-activated protein kinases (MAPKs) and phosphatidylinositol-3-kinase/AKT (PI3K/AKT) pathways. Se-SP after Se addition achieved enhanced potential in inhibiting high glucose-induced calcification, which validated that Se-SP as a new Se species could be a highly effective treatment for human CCD.