Association of lower extremity arterial calcification with amputation and mortality in patients with symptomatic peripheral artery disease

Impact of iliac artery calcification burden on mid-term outcomes in femoropopliteal artery disease treated with drug-coated balloon combined with provisional bare metal stenting

OBJECTIVE

Severe arterial calcification is an important factor affecting endovascular therapy in patients with the lower extremity atherosclerotic occlusive disease. The aim of this study was to investigate whether different calcification burden of iliac artery is associated with various clinical outcomes following drug-coated balloon (DCB) combined with provisional bare metal stenting for femoral-popliteal artery disease.

METHODS

This was a retrospective cohort study of patients who underwent drug-coated balloon combined with stent placement for femoral-popliteal artery disease from January 2018 to July 2022. All patients received a computed tomography scan of the lower extremities before undergoing DCB combined with provisional bare metal stenting. The different degrees of iliac artery calcification (IAC) were evaluated using a semi-quantitative computed tomography scoring method including calcification length, circumference and morphology. The Kaplan-Meier method and Cox regression were performed to assess the correlations between calcification burden and short-to medium-term outcomes.

RESULTS

A total of 290 patients (mean age, 73.53 ± 9.64 years; 68.3 % male) were included in the study. 100 patients (34.5 %) had mild IAC scores, 96 patients (33.1 %) had moderate IAC scores, and 94 patients (32.4 %) had severe IAC scores. There were remarkable differences in the rate of 2-year primary patency and freedom from clinically driven target lesion revascularization (FCD-TLR) between the three groups (P < 0.001). The severe group indicated lower rates of amputation-free survival (AFS) compared with the mild and moderate groups (P < 0.001, respectively). Meanwhile, the severe group prompted higher rates of all-cause mortality, major amputation, and minor amputation compared with the mild and moderate group. According to stepwise multivariable cox regression analysis, severe and moderate IAC burden were linked to poor patency (HR, 2.87; 95 % CI, 1.81-4.55; HR, 1.94; 95 % CI, 1.24-3.05) and AFS (HR, 2.12; 95 % CI, 1.44-3.11; HR, 1.75; 95 % CI, 1.26-2.43).

CONCLUSIONS

Higher IAC burden is significantly correlated with lower 2-year primary patency and AFS in patients undergoing drug-coated balloon combined with provisional bare metal stenting. Consequently, a preoperative evaluation of IAC burden may aid in tailoring individualized treatment strategies.

One-year Clinical Outcomes and Predictors of Distal Embolization After JETSTREAM™ Atherectomy for Calcified Femoropopliteal Artery Lesions: Results From the JET-FORWARD Study

PURPOSE

This study aimed to identify predictors of distal embolization following JETSTREAM™ atherectomy for calcified femoropopliteal lesions and evaluate 1-year clinical outcomes in a real-world setting.

MATERIALS AND METHODS

We analyzed data from 109 patients with 121 calcified femoropopliteal lesions who underwent JETSTREAM™ atherectomy therapy between October 2022 and December 2023 as part of the JET-FORWARD study, a retrospective, single-arm, multicenter study. Distal embolization incidence and risk factors were the primary focus, while 1-year primary patency served as efficacy outcome measures. Safety outcomes also included mortality and major target limb amputation.

RESULTS

The mean lesion length was 15.5 ± 9.4 cm, and the technical success rate-defined as residual stenosis less than 30% and absence of grade C or higher dissection post-procedure-was 93.4%. Angiographically significant distal embolization occurred in 35.5% of cases during the index procedure. On multivariate analysis, poor tibial runoff (≤ 1 tibial artery), severe small artery disease, nodular calcification, and debulking lengths > 10 cm were independent predictors of distal embolization. The 1-month mortality and 1-year limb salvage rates were 2.8% and 98.9%, respectively. The 1-year primary patency rate was 88.9%.

CONCLUSION

Angiographically significant distal embolization occurred in 35.5% of cases with JETSTREAM atherectomy, while 1-year outcomes remained favorable in treating femoropopliteal lesions. This study also identified four predictors of distal embolization. Thus, careful risk factor evaluation and patient selection are essential during atherectomy.

Metabolic dysfunction-associated steatotic liver disease (MASLD) biomarkers and progression of lower limb arterial calcification in patients with type 2 diabetes: a prospective cohort study

BACKGROUND

Studies have demonstrated that both lower limb arterial calcification and metabolic dysfunction-associated steatotic liver disease (MASLD) are linked to the development of peripheral artery disease. However, the potential relationship between MASLD biomarkers and progression of lower limb arterial calcification in individuals with type 2 diabetes (T2D) remains unclear. This study aimed to investigate whether the biomarkers of MASLD included in the FibroMax® panels are associated with the progression of lower limb arterial calcification in patients with T2D.

METHODS

The lower limb arterial calcification score (LLACS) was evaluated through computed tomography at baseline and after an average follow-up of 31.2 ± 3.7 months in a cohort of 150 patients with T2D. We also measured the serum biomarkers included in the FibroMax® panels (SteatoTest®, FibroTest®, NashTest®, ActiTest®). The predictive ability of these biomarkers of MASLD on LLACS progression was assessed through univariate and multivariate linear regression models, principal component regression analysis, as well as machine learning algorithms.

RESULTS

During the follow-up period, LLACS increased in 127 (85%) of the 150 patients with T2D. In univariate analysis, the annualized change in LLACS was positively and mainly correlated with baseline LLACS (r = 0.860, p < 0.0001), the FibroTest® score (r = 0.304, p = 0.0002), and age (r = 0.275, p = 0.0006), and negatively correlated with glomerular filtration rate (r = - 0.242, p = 0.003). In multivariate analysis, the FibroTest® score remained independently associated with the annualized change in LLACS, after adjusting for baseline LLACS and risk factors for lower extremity artery disease (β coefficient [95% confidence interval]: 988 [284-1692], p = 0.006). This association persisted even after adjustment for variables selected by principal component analysis (β = 1029 [289-1768], p = 0.007). Two advanced machine learning models identified the FibroTest® score as the second most important predictor of annualized change in LLACS, following baseline LLACS.

CONCLUSIONS

This study represents the first demonstration of an independent relationship between a non-invasive liver fibrosis test and the progression of lower limb arterial calcification in patients with T2D. Beyond its utility in assessing liver fibrosis, the FibroTest® could be a valuable and easy-to-use biomarker for predicting the risk of worsening lower limb arterial calcification.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT02431234.

Fracture and Fragmentation of Vascular Calcifications by Focused Ultrasound

Peripheral artery disease results in ischemia necessitating interventions such as balloon angioplasty. However, calcified lesions resist balloon and stent expansion, leading to poor outcomes. We hypothesized that focused ultrasound can fracture vascular calcifications and enable balloon angioplasty. In a first experiment, focused ultrasound was applied to ex vivo human calcified plaque specimens to determine its effects based on micro-CT imaging. In a second experiment, ultrasound was applied to an in vitro phantom to evaluate whether the effects enable balloon expansion. Fractures, thinning, and disintegration of calcified sections were observed in 15 of 18 treated human plaque samples. Minor mechanical disruption to soft plaque was found in 33% of samples. In tissue phantoms, n = 10/10 samples were successfully expanded by a water-filled angioplasty balloon with ultrasound applied prior to or during expansion. No controls (n = 0/10) were expanded. These results indicate focused-ultrasound plaque fracture is feasible and may enhance balloon angioplasty.

Advances in intravascular lithotripsy: mechanisms, devices, and clinical applications

INTRODUCTION

Peripheral arterial disease (PAD) complicates endovascular interventions due to vascular calcifications, which compromise procedural success and long-term outcomes. Intravascular lithotripsy (IVL) represents a promising innovation to modify calcified lesions with shockwaves, addressing unmet clinical needs.

AREAS COVERED

This review explores the mechanisms, devices, and clinical applications of IVL in PAD treatment. It highlights the limitations of conventional approaches (high-pressure balloons, specialty balloons, atherectomy), which often result in suboptimal lesion preparation and procedural complications. Particular emphasis is placed on the combination of atherectomy and IVL, as well as the various IVL devices available and in development, beyond those from Shockwave Medical. Additionally, we discuss future perspectives, including drug penetration enhancement and the issue of post-IVL recoil. Additionally, the literature review methodology, encompassing searches in PubMed and Embase, from January 2008 to December 2023, is briefly outlined.

EXPERT OPINION

IVL offers a safe, effective, and innovative approach to treating calcified lesions while preserving surrounding tissues. However, the current evidence, mainly derived from industry-funded studies, is limited by heterogeneous calcification classifications and a lack of long-term outcome data. Independent research is essential to define IVL's role in PAD treatment algorithms, especially regarding its cost-effectiveness and long-term primary patency outcomes.

Objective Evaluation With Noncontrast Computed Tomography Can Reveal Calcified Plaque Solidity in Peripheral Artery Diseases

PURPOSE

The presence of severely calcified plaque remains problematic in endovascular therapy, and no specific endovascular treatment strategy has been established. Estimating plaque solidity before the procedure may help operators penetrate calcified plaque with a guide wire. The aim of this study was to establish a method of measuring plaque solidity with noncontrast computed tomography (CT).

METHODS

This retrospective, single-center study included consecutive patients who, between October 2020 and July 2022, underwent noncontrast 5 mm and 1 mm CTs before endovascular therapy to penetrate calcified plaque with a wire in the common femoral, superficial femoral, and popliteal arteries. Three cross-sectional CT slices were selected. To target a calcified plaque lesion, the operator identified a region of interest, which corresponded to 24×24 pixels, and Hounsfield unit (HU) values of each pixel were displayed on the CT image. The average HU values and the ratio of number of pixels of lower values (130-599 HU) represented plaque solidity. We used the Mann-Whitney-Wilcoxon rank-sum test and the chi-square test to compare the solidity of plaques penetrated and not penetrated by the wire.

RESULTS

We evaluated 108 images of 36 calcified plaque lesions (in 19 patients). The wire penetrated 28 lesions (77.8%) successfully. The average HU value was significantly lower in the lesions that the wire penetrated than in the others, in both the 5 mm CT slices (434.7±86.8 HU vs 554.3±112.7 HU, p=0.0174) and 1 mm slices (497.8±103.1 HU vs 593.5±114.5 HU, p=0.0381). The receiver operating curve revealed that 529.9 and 533.9 HU in the 5 and 1 mm slices, respectively, were the highest values at which wires could penetrate. Moreover, at the lesions that were penetrates successfully, the ratio of number of lower HU value pixels was significantly higher both in 5 mm slice CTs (74.7±13.4 vs 61.7±13.1%, p=0.0347) and 1 mm (68.7±11.8 vs 57.1±11.4%, p=0.0174).

CONCLUSION

The use of noncontrast CT to evaluate plaque solidity was associated with successful wire penetration of calcified lesions in peripheral arteries.

CLINICAL IMPACT

This study revealed an association between the wire penetration inside calcified plaque and plaque solidity estimated using non-contrasted computed tomography. The mean Hounsfield unit values of three cross-sections in calcified plaques were associated with the successful wire penetration. This wire penetration difficulty is associated with extended procedure time, excessive radiation exposure, usage of extra contrast agents, and increased medical costs. Therefore, estimating calcified plaque solidity before procedure enables us to choose effective and lean procedures. In addition, to predict the success of dilating calcified plaque from the inside is also beneficial when the operator wants to avoid extra scaffold implantation for target lesions.

Association of Iliofemoral Calcium Score and Major Vascular Complications within the First Year after Lower Limb Endovascular Revascularization

BACKGROUND

The accumulation of calcium load in peripheral lower extremity arteries has been associated with increased severity of peripheral artery disease (PAD) and mortality. While calcium scores are commonly calculated from non-contrast computed tomography (CT) scans, patients with PAD often undergo contrast-enhanced CT scans. This study aims to explore the association between a length-adjusted calcium score (LACS) of the iliofemoral arteries, determined through pre-intervention contrast-enhanced CT, and major adverse events in patients with chronic limb-threatening ischemia (CLTI).

METHODS

A cohort of CLTI patients subjected to endovascular revascularization between 2005 and 2017 at a tertiary referral center were categorized into 2 groups. The complication group experienced one of the composite outcomes (reintervention, above-the-ankle amputation, and/or all-cause mortality within 1 year of the primary endovascular procedure), while control patients did not encounter this composite endpoint. Patients from the complication group were matched one-to-one with controls based on sex and Fontaine classification. LACS was calculated (Ca volume[mm3]/length[cm]) at 3 arterial segments; 1. the common iliac artery (CIA), 2. the external iliac artery and common femoral artery (EIA + CFA), and 3. the superficial femoral artery plus the popliteal artery (SFA + PA). Binary logistic regression analysis was conducted to investigate the association between LACS in the different arterial segments and the occurrence of the composite binary outcome (complication and control) and LACS of the different segments, adjusting influences of age, sex, BMI >25, Fontaine classification, diabetes mellitus type 1 & 2, chronic kidney disease stage, and hemodialysis treatment.

RESULTS

Sixty-four CLTI patients were included in this study (complication group [n = 32], and control group [n = 32]). A significant difference (higher LACS was found for the complication group in the CIA, the SFA + PA, as well as the total trajectory. CLTI patients with high LACS in the SFA + PA or the total trajectory were more likely to suffer adverse events (SFA + PA: OR: 1.010, 95% CI: 1.000-1.020, P = 0.04; Total LACS: OR: 1.008, 95% CI: 1.000-1.017, P = 0.05).

CONCLUSIONS

Patients with a high calcium load in the ilio-femoral arteries are at increased risk of major adverse events during 1 year after endovascular revascularization. The calcium score, derived from contrast-enhanced CT scans, holds potential utility in decision making for CLTI patients.

Low Muscle Mass is Independently Associated with an Increased Risk of Having Lower Limb Atherosclerosis in T2DM Patients

Background and Aims

Existing research suggests that low muscle mass is independently associated with carotid atherosclerosis, but its relationship with lower extremity arterial atherosclerosis in type 2 diabetes mellitus (T2DM) patients remains unclear. This study aims to investigate the association between low skeletal muscle mass and lower extremity arterial atherosclerosis in T2DM patients, in hopes of providing a scientific basis for early diagnosis and treatment.

Methods

This cross-sectional study recruited a total of 276 patients with T2DM who underwent bioelectrical impedance analysis, lower limb artery ultrasonography, brachial-ankle pulse wave velocity(baPWV) arterial stiffness measurement, and blood tests. An skeletal muscle index (SMI) < 7.0kg/m2 in men and an SMI< 5.7kg/m2 in women were defined as low skeletal muscle mass. Lower limb atherosclerosis was defined as the presence of atherosclerotic plaques in the lower extremity arteries.

Results

In our study of 276 T2DM patients, 224 (81.1%) presented with lower limb atherosclerosis: 194 (70.2%) with simple lower limb arterial plaques, 15 (5.4%) with lower limb arterial stenosis, and 15 (5.4%) with lower limb arterial occlusion. 52 (18.8%) were diagnosed with low skeletal muscle mass. Logistic regression analysis indicated the risk of having overall lower limbs atherosclerosis increased with the prevalence of low skeletal muscle (OR= 6.175,95% CI 1.328-28.711); Patients with a low skeletal muscle mass had a higher prevalence of simple arterial plaque (OR= 6.225,95% CI 1.339-28.935) and arterial occlusion (OR=12.345,95% CI 1.221-124.808); after the adjustment for clinical risk factors. Spearman's analysis showed significant negative correlations between total-P1NP and baPWV (r=-0.166, p=0.008), N-MID and baPWV (r=-0.163, p=0.009), and β-CTX and baPWV (r=-0.141, p=0.024).

Conclusion

Low muscle mass is independently associated with an increased risk of having lower limb atherosclerosis in T2DM patients. And there may be some relationship between BTMs and arteriosclerosis of the lower limb atherosclerosis in T2DM.

Inter- and Intra-observer Agreement of the Peripheral Arterial Calcium Scoring System in Patients Undergoing (Infra)Popliteal Endovascular Interventions

PURPOSE

Peripheral arterial calcification is an important predictor of outcomes after both conservative and endovascular treatment. Digital subtraction angiography (DSA)-based calcification scores are limited by low sensitivity and inter-observer agreement. The Peripheral Arterial Calcium Scoring System (PACSS) assesses the severity of target lesion calcification. The newly introduced modified PACSS (mPACSS) also evaluates target vessel calcification. This study aimed to assess the inter- and intra-observer reliability of PACSS and mPACSS on computed tomography angiography (CTA) in (infra)popliteal endovascular interventions.

METHODS

A random sample of 50 limbs from the prospective multicenter Dutch Chronic Lower Limb-Threatening Ischemia Registry (THRILLER) were included. Three experienced independent raters scored PACSS on CTA. Three months later, one blinded rater assessed the same 50 CTA scans, keeping track of assessment time. The reliability of the original 5-step PACSS, a simplified binary PACSS (0-2 vs 3-4) and the 7-step mPACSS were tested using Cohen's and Fleiss' kappa statistics.

RESULTS

In total, 50 limbs (mean age 70.1 ± 11.0, 29 men) with 41 popliteal and 40 infrapopliteal lesions were scored. Inter-observer agreement of PACSS and binary PACSS were moderate (κ = 0.60) and substantial (κ = 0.72), respectively, while intra-observer agreement was almost perfect in both scores (κ = 0.86). Inter- and intra-observer agreement of mPACSS were moderate (κ = 0.48) and substantial (κ = 0.77), respectively. Mean assessment time for an experienced rater was 3.43 ± 0.93 min per CTA scan.

CONCLUSION

Both the semi-quantitative PACSS and mPACSS scores for (infra)popliteal arteries can be performed reliably on pre-operative CTA.

Efferocytosis in atherosclerosis

Cardiovascular disease is the leading cause of death worldwide, and it commonly results from atherosclerotic plaque progression. One of the increasingly recognized drivers of atherosclerosis is dysfunctional efferocytosis, a homeostatic mechanism responsible for the clearance of dead cells and the resolution of inflammation. In atherosclerosis, the capacity of phagocytes to participate in efferocytosis is hampered, leading to the accumulation of apoptotic and necrotic tissue within the plaque, which results in enlargement of the necrotic core, increased luminal stenosis and plaque inflammation, and predisposition to plaque rupture or erosion. In this Review, we describe the different forms of programmed cell death that can occur in the atherosclerotic plaque and highlight the efferocytic machinery that is normally implicated in cardiovascular physiology. We then discuss the mechanisms by which efferocytosis fails in atherosclerosis and other cardiovascular and cardiometabolic diseases, including myocardial infarction and diabetes mellitus, and discuss therapeutic approaches that might reverse this pathological process.

Intravascular lithotripsy in infra-popliteal peripheral artery disease

Chronic limb-threatening ischemia (CLTI) carries a significant risk of limb loss and thus demands urgent attention. Calcified atherosclerotic disease affecting the infra-popliteal (IP) arteries poses a formidable challenge for effective revascularization due to the narrow vessel diameter and the common presence of extensively calcified, long occlusive lesions. Intravascular lithotripsy (IVL) is an endovascular treatment that induces microfractures in the medial calcifications of blood vessels, thereby facilitating the clearance of calcified obstructive arterial lesions. This review assesses the growing body of evidence from multiple prospective studies that have investigated the role of IVL in the treatment of peripheral arterial disease (PAD) involving the IP segment. The clinical efficacy of IVL has been extensively studied and validated in various trials and real-world experiences. These studies consistently demonstrate IVL's ability to achieve vessel preparation, with excellent procedural success rates and low rates of major adverse events. Moreover, IVL has shown remarkable versatility, proving effective across a wide spectrum of PAD, including iliac artery disease, femoropopliteal disease and IP calcified disease. The available results from existing literature are encouraging and demonstrates safety and efficacy of the technology in treating calcified PAD. Additional studies on a larger scale are needed to better understand its long-term effects.

Influence of a Novel Morphology-Driven Classification on Limb Salvage after Isolated Tibial Intervention for Chronic Limb Threatening Ischemia

BACKGROUND

Infra-popliteal interventions for chronic limb-threatening ischemia (CLTI) can be impacted by the morphology of the tibial vessels. The aim of this study was to examine the impact of a novel morphology-driven classification on the outcomes of isolated tibial intervention for CLTI.

METHODS

A database of patients undergoing isolated tibial interventions for CLTI at a single center between 2010 and 2020 was retrospectively queried. Patients with isolated infra-popliteal disease were identified, and their anatomy was scored as present or absent for lesion calcification (1 point), target vessel diameter<3.0 mm (1 point), lesion length>300 mm (1 point), and poor pedal runoff score (1 point). Patients were then divided into 3 groups: low risk (0 or 1 points), moderate risk (2 points), and high risk (3 or 4 points). Intention to treat analysis by the patient was performed. Limb-based patency (the absence of reintervention, occlusion, critical stenosis [>70%], or hemodynamic compromise with ongoing symptoms of CLTI as it related to the patency of the preoperatively determined target artery pathway) was assessed. Patient-oriented outcomes of amputation-free survival (AFS; survival without major amputation) and freedom from major adverse limb events (MALE; above ankle amputation of the index limb or major reintervention: new bypass graft, jump/interposition graft revision) were evaluated.

RESULTS

1,607 patients (55% male, average age 60 years, 3,846 vessels) underwent tibial intervention for CLTI. The majority of the patients were diabetic and of Hispanic origin. Morphologically, 27%, 31%, and 42% of the vessels were categorized as low risk, moderate risk, and high risk, respectively. There was a significant worsening of the infra-popliteal Global Limb Anatomic Staging System (GLASS) grading as the morphological risk increased. The 30-day major adverse cardiac events (MACE) were equivalent across the groups and were under the stated objective performance goal (OPG) of ≤10%. In contrast, both the 30-day MALE and the 30-day major amputations were significantly different across the groups, with the low-risk group remaining under the OPG of ≤9% and ≤4%, respectively, while the moderate risk and high risk exceeded the goal threshold. For the OPG, freedom from MALE was 60 ± 5%, 46 ± 5%, and 22 ± 9% at 5 years for low-, moderate-, and high-risk groups, respectively (mean ± standard error of the mean; P = 0.008). Overall AFS was 55 ± 5%, 37 ± 6%, and 18 ± 7% at 5 years for low-, moderate-, and high-risk groups, respectively (mean ± standard error of the mean; P = 0.003).

CONCLUSIONS

Tibial anatomic morphology impacts isolated tibial endovascular intervention with adverse morphology associated with poorer short- and long-term outcomes. Risk stratification based on anatomic predictors should be an additional consideration as one intervenes on infra-popliteal vessels for CLTI.

Pedal medial arterial calcification influences the outcomes of isolated infra-malleolar interventions for chronic limb-threatening ischemia

OBJECTIVE

Inframalleolar disease is present in most diabetic patients presenting with tissue loss. Inframalleolar (pedal) artery disease and pedal medial arterial calcification (pMAC) are associated with major amputation in patients with chronic limb-threatening ischemia (CLTI). This study aimed to examine the impact of pMAC on the outcomes after isolated inframalleolar (pedal artery) interventions.

METHODS

A database of lower extremity endovascular intervention for patients with tissue loss between 2007 and 2022 was retrospectively queried. Patients with CLTI were selected, and those undergoing isolated inframalleolar intervention on the dorsalis pedis and medial and lateral tarsal arteries and who had foot x-rays were identified. X-rays were assessed blindly for pMAC and scored on a scale of 0 to 5. Patients with concomitant superficial femoral artery and tibial interventions were excluded. Intention to treat analysis by the patient was performed. Amputation-free survival (survival without major amputation) was evaluated.

RESULTS

A total of 223 patients (51% female; 87% Hispanic; average age, 66 years; 323 vessels) underwent isolated infra-malleolar intervention for tissue loss. All patients had diabetes, 96% had hypertension, 79% had hyperlipidemia, and 63% had chronic renal insufficiency (55% of these were on hemodialysis). Most of the patients had Wound, Ischemia, and foot Infection (WIfI) stage 3 disease and had various stages of pMAC: severe (score = 5) in 48%, moderate (score = 2-4) in 31%, and mild (score = 0-1) in 21% of the patients. Technical success was 94%, with a median of one vessel treated per patient. All failures were in severe pMAC. Overall, major adverse cardiovascular events was 0.9% at 90 days after the procedure. Following the intervention, most patients underwent a planned forefoot amputation (single digit, multiple digits, ray amputation, or trans-metatarsal amputation). WIfI ischemic grade was improved by 51%. Wound healing at 3 months was 69%. Those not healing underwent below-knee amputations. The overall 5-year amputation-free survival rate was 35% ± 9%. The severity of pMAC was associated with decreased AFS.

CONCLUSIONS

Increasing severity of pMAC influences the technical and long-term outcomes of infra-malleolar intervention in diabetes. Severe pMAC is associated with amputation and should be considered as a variable in the shared decision-making of diabetic patients with CLTI.

Shockwave Intravascular Lithotripsy Use in the Femoro-Popliteal Segment: Considerations From an Expert Pan-European Panel Regarding Best-Care Practice

PURPOSE

Produce expert recommendations regarding the optimal use of Shockwave intravascular lithotripsy (IVL) when treating femoro-popliteal steno-occlusive peripheral artery disease (PAD), guiding operators to use Shockwave IVL.

MATERIALS AND METHODS

A modified 3-step Delphi process was used to gain consensus surrounding preoperative/intraoperative/postoperative considerations when using Shockwave IVL for femoro-popliteal PAD. This included a structured survey, focus-group (with qualitative thematic analysis of views expressed), and final confirmatory round; participants were recruited across Europe including the United Kingdom/Switzerland.

RESULTS

Following a review to inform an online survey, 25 experts took part in a survey (5 European countries, 2023), followed by a focus-group (15 participants), 9 interviews, and final confirmatory round. A list of recommendations was prepared where at least moderate-level or high-level agreement was reached (≥70% participants agreeing). The recommendations relate to the optimal preoperative imaging, preoperative preparation(s), intraoperative imaging and use of adjuncts, as well as postoperative course, when using Shockwave IVL.

CONCLUSION

A list of expert recommendations is provided guiding the optimal use of Shockwave IVL in femoro-popliteal PAD. This will help operators achieve better clinical outcomes.

CLINICAL IMPACT

This pan-European panel of experts using intravascular lithotripsy in routine peripheral arterial disease endovascular practice has provided important insights into best care practices before, during, and after such procedures. Several recommendations have been produced based on a structured consensus process to guide clinicians globally. This will improve and standardise the use of this technology in the femoro-popliteal arterial segment.

Objective Methods to Assess Aorto-Iliac Calcifications: A Systematic Review

Vascular calcifications in aorto-iliac arteries are emerging as crucial risk factors for cardiovascular diseases (CVDs) with profound clinical implications. This systematic review, following PRISMA guidelines, investigated methodologies for measuring these calcifications and explored their correlation with CVDs and clinical outcomes. Out of 698 publications, 11 studies met the inclusion criteria. In total, 7 studies utilized manual methods, while 4 studies utilized automated technologies, including artificial intelligence and deep learning for image analyses. Age, systolic blood pressure, serum calcium, and lipoprotein(a) levels were found to be independent risk factors for aortic calcification. Mortality from CVDs was correlated with abdominal aorta calcification. Patients requiring reintervention after endovascular recanalization exhibited a significantly higher volume of calcification in their iliac arteries. Conclusions: This review reveals a diverse landscape of measurement methods for aorto-iliac calcifications; however, they lack a standardized reproducibility assessment. Automatic methods employing artificial intelligence appear to offer broader applicability and are less time-consuming. Assessment of calcium scoring could be routinely employed during preoperative workups for risk stratification and detailed surgical planning. Additionally, its correlation with clinical outcomes could be useful in predicting the risk of reinterventions and amputations.

Structural and Mechanical Properties of Human Superficial Femoral and Popliteal Arteries

The femoropopliteal artery (FPA) is the main artery in the lower limb. It supplies blood to the leg muscles and undergoes complex deformations during limb flexion. Atherosclerotic disease of the FPA (peripheral arterial disease, PAD) is a major public health burden, and despite advances in surgical and interventional therapies, the clinical outcomes of PAD repairs continue to be suboptimal, particularly in challenging calcified lesions and biomechanically active locations. A better understanding of human FPA mechanical and structural characteristics in relation to age, risk factors, and the severity of vascular disease can help develop more effective and longer-lasting treatments through computational modeling and device optimization. This review aims to summarize recent research on the main biomechanical and structural properties of human superficial femoral and popliteal arteries that comprise the FPA and describe their anatomy, composition, and mechanical behavior under different conditions.

Mechanical, structural, and physiologic differences between above and below-knee human arteries

Peripheral Artery Disease (PAD) affects the lower extremities and frequently results in poor clinical outcomes, especially in the vessels below the knee. Understanding the biomechanical and structural characteristics of these arteries is important for improving treatment efficacy, but mechanical and structural data on tibial vessels remain limited. We compared the superficial femoral (SFA) and popliteal (PA) arteries that comprise the above-knee femoropopliteal (FPA) segment to the infrapopliteal (IPA) anterior tibial (AT), posterior tibial (PT), and fibular (FA) arteries from the same 15 human subjects (average age 52, range 42-67 years, 87 % male). Vessels were imaged using μCT, evaluated with biaxial mechanical testing and constitutive modeling, and assessed for elastin, collagen, smooth muscle cells (SMCs), and glycosaminoglycans (GAGs). IPAs were more often diseased or calcified compared to the FPAs. They were also twice smaller, 53 % thinner, and significantly stiffer than the FPA longitudinally, but not circumferentially. IPAs experienced 48 % higher physiologic longitudinal stresses (62 kPa) but 27 % lower circumferential stresses (24 kPa) and similar cardiac cycle stretch of <1.02 compared to the FPA. IPAs had lower longitudinal pre-stretch (1.12) than the FPAs (1.29), but there were no differences in the stored elastic energy during pulsation. The physiologic circumferential stiffness was similar in the above and below-knee arteries (718 kPa vs 754 kPa). Structurally, IPAs had less elastin, collagen, and GAGs than the FPA, but maintained similar SMC content. Our findings contribute to a better understanding of segment-specific human lower extremity artery biomechanics and may inform the development of better medical devices for PAD treatment. STATEMENT OF SIGNIFICANCE: Peripheral Artery Disease (PAD) in the lower extremity arteries exhibits distinct characteristics and results in different clinical outcomes when treating arteries above and below the knee. However, their mechanical, structural, and physiologic differences are poorly understood. Our study compared above- and below-knee arteries from the same middle-aged human subjects and demonstrated distinct differences in size, structure, and mechanical properties, leading to variations in their physiological behavior. These insights could pave the way for creating location-specific medical devices and treatments for PAD, offering a more effective approach to its management. Our findings provide new, important perspectives for clinicians, researchers, and medical device developers interested in treating PAD in both above- and below-knee locations.

Effect of chronic kidney disease induced calcification on peripheral vascular perfusion using near-infrared spectroscopic imaging

Low-cost techniques that can detect the presence of vascular calcification (VC) in chronic kidney disease (CKD) patients could improve clinical outcomes. In this study, we established a near-infrared spectroscopy-based imaging technique to determine changes in peripheral hemodynamics due to CKD-induced VC. Mice were fed a high-adenine diet with either normal or high levels of phosphate to induce CKD with and without VC, respectively. The mice tail was imaged to evaluate hemodynamic changes in response to occlusion. The rate of change in oxyhemoglobin in response to occlusion showed a statistically significant difference in the presence of VC in the mice.

Circumferential degree of tibial artery calcification is associated with infrapopliteal endovascular revascularization outcomes in patients with chronic limb-threatening ischemia

BACKGROUND

Tibial artery calcification (TAC) is correlated with an increased risk of amputation and mortality in patients with chronic limb-threatening ischemia (CLTI). The association between calcification characteristics and adverse limb events of CLTI. However, it has not been assessed. This study aims to assess the relationship between the characteristics of TAC based on computed tomography angiography (CTA) scans and postoperative outcomes in patients with CLTI undergoing infrapopliteal endovascular therapy.

METHODS

This was a retrospective study of patients who underwent infrapopliteal endovascular revascularization for CLTI and had a preoperative CTA scan. Based on CTA, TAC was divided into the following categories: annularity, thickness, continuity and severity. Cox regression models using generalized estimating equations were performed to assess the relationship between calcification characteristics and postoperative outcomes. The outcomes evaluated were the occurrence of all cause mortality (ACM) and unplanned amputation.

RESULTS

Among the 148 patients undergoing endovascular, there were 50 (33.8%) patients died and 26 (17.6%) patients underwent unplanned amputation. Annular calcification was more common in the ACM group than in the non-ACM group. No significant differences were found between the two groups with regard to the probability of calcification in the thickness and the continuity (P>0.05). Patients in the unplanned amputation group had significantly annular, thin and continuity calcifications (P<0.05) than those in the non-unplanned amputation group. The presence of annular calcification was an independent predictor of ACM (hazard ratio (HR), 3.186; 95% confidence interval (CI), 1.781-5.702; P<0.001) and unplanned amputation (HR, 3.739; 95% CI, 1.707-8.191; P<0.05).

CONCLUSIONS

Among patients with CLTI, the occurrence of annular calcification in the tibial artery are related to a greater chance of ACM and unplanned amputation in the postoperative period. The circumferential degree of TAC of the operated limb can be considered as a marker of clinical prognosis in this group of patients.

Lower limb arterial calcification and its clinical relevance with peripheral arterial disease

Lower limb arterial calcification (LLAC) is associated with an increased risk of mortality and it predicts poor outcomes after endovascular interventions in patients with peripheral artery disease (PAD). Detailed histological analysis of human lower artery specimens pinpointed the presence of LLAC in two distinct layers: the intima and the media. Intimal calcification has been assumed to be an atherosclerotic pathology and it is associated with smoking and obesity. It becomes instrumental in lumen stenosis, thereby playing a crucial role in disease progression. On the contrary, medial calcification is a separate process, systematically regulated and linked with age advancement, diabetes, and chronic kidney disease. It prominently interacts with vasodilation and arterial stiffness. Given that both types of calcifications frequently co-exist in PAD patients, it is vital to understand their respective mechanisms within the context of PAD. Calcification can be easily identifiable entity on imaging scans. Considering the highly improved abilities of novel imaging technologies in differentiating intimal and medial calcification within the lower limb arteries, this review aimed to describe the distinct histological and imaging features of the two types of LLAC. Additionally, it aims to provide in-depth insight into the risk factors, the effects on hemodynamics, and the clinical implications of LLAC, either occurring in the intimal or medial layers.

Automated Measurement of Vascular Calcification in Femoral Endarterectomy Patients Using Deep Learning

Atherosclerosis, a chronic inflammatory disease affecting the large arteries, presents a global health risk. Accurate analysis of diagnostic images, like computed tomographic angiograms (CTAs), is essential for staging and monitoring the progression of atherosclerosis-related conditions, including peripheral arterial disease (PAD). However, manual analysis of CTA images is time-consuming and tedious. To address this limitation, we employed a deep learning model to segment the vascular system in CTA images of PAD patients undergoing femoral endarterectomy surgery and to measure vascular calcification from the left renal artery to the patella. Utilizing proprietary CTA images of 27 patients undergoing femoral endarterectomy surgery provided by Prisma Health Midlands, we developed a Deep Neural Network (DNN) model to first segment the arterial system, starting from the descending aorta to the patella, and second, to provide a metric of arterial calcification. Our designed DNN achieved 83.4% average Dice accuracy in segmenting arteries from aorta to patella, advancing the state-of-the-art by 0.8%. Furthermore, our work is the first to present a robust statistical analysis of automated calcification measurement in the lower extremities using deep learning, attaining a Mean Absolute Percentage Error (MAPE) of 9.5% and a correlation coefficient of 0.978 between automated and manual calcification scores. These findings underscore the potential of deep learning techniques as a rapid and accurate tool for medical professionals to assess calcification in the abdominal aorta and its branches above the patella.

Twelve-Month Outcomes of Intravascular Lithotripsy for Treatment of Calcified Popliteal and Infrapopliteal Lesions in Patients With Chronic Limb-Threatening Ischemia

PURPOSE

Vessel calcification is estimated to be present in 30% to 50% of patients with peripheral arterial disease (PAD) and is one of the main challenges in endovascular treatment. The popliteal artery is unique compared with other arteries due to its exposure to significant deformation and biomechanical stress during knee motion. Intravascular lithotripsy (IVL) is a novel technique that uses acoustic pressure waves to cause microfractures within the intimal and medial wall calcification. Intravascular lithotripsy is safe in femoropopliteal and infrapopliteal lesions, but follow-up studies are lacking. Therefore, the purpose of this study was to describe the first follow-up outcomes of IVL in popliteal and infrapopliteal arterial disease.

METHODS

This prospective, multicenter cohort study included all patients treated with IVL in the popliteal and infrapopliteal arteries at 4 sites. Standardized follow-up with duplex ultrasonography was scheduled at 6 to 8 weeks and 12 months. The primary safety endpoint was a composite of major adverse events (MAEs) at 30 days. Primary efficacy endpoints were primary patency, limb salvage, and amputation-free survival (AFS) at 12 months. Secondary endpoints were primary-assisted patency and freedom from target lesion revascularization (TLR). Endpoints were distributed for patients with chronic limb-threatening ischemia (CLTI) and intermittent claudication (IC) and estimated using the Kaplan-Meier method.

RESULTS

Between April 2021 and March 2023, 29 patients with 30 limbs were treated. Diabetes mellitus (DM) and CLTI were present in 62.1% and 80.0% of patients, respectively. Within the 32 treated lesions, severe calcification was present in 84.4% and bailout stenting was necessary in 12.5% of the lesions. Four MAEs occurred within 30 days: 1 closure device failure, 1 major amputation, and 2 deaths, neither of which was related to the study device. The primary patency, primary-assisted patency, freedom from TLR, limb salvage, and AFS at 12 months were 68.8%, 90.0%, 93.3%, 83.9%, and 57.1% for CLTI patients, respectively. No events occurred in restenosis, re-occlusion, TLR, major amputation, or mortality in patients with IC.

CONCLUSIONS

This first-ever analysis on follow-up outcomes of IVL in the popliteal and infrapopliteal arteries demonstrated promising safety and efficacy outcomes with a low rate of bailout stenting.

CLINICAL IMPACT

Vessel calcification is a common feature in peripheral arterial disease (PAD) and is one of the main challenges in endovascular treatment. The popliteal artery is subjected to biomechanical stress during knee motion, which makes stenting unappealing and often leads to worse clinical outcomes. This study aimed to describe the first follow-up outcomes of IVL in popliteal and infrapopliteal arterial disease. As in line with previous studies, no relevant procedural complications were found and the rate of bail-out stenting was only 12.5%. Moreover, in a complex patient population, this study demonstrated promising safety and efficacy outcomes. The comparison of IVL with angioplasty alone or other vessel preparation devices for popliteal and infrapopliteal arterial disease is warranted.

Does Femoral Arterial Calcification Have an Effect on Mortality in Patients Who Underwent Hemiarthroplasty Due to Hip Fracture?

AIM

We aimed to investigate the effect of femoral arterial calcification on mortality in patients who underwent hemiarthroplasty due to hip fracture.

MATERIAL AND METHODS

In our study, 481 patients who were operated for hip fracture between 01.01.2015 and 01.01.2021 were evaluated retrospectively. Femoral arterial calcification on the fractured side was evaluated in the preoperative pelvic anteroposterior (AP) X-ray, and the patients were divided into two subgroups according to the presence or absence of femoral arterial calcification. The overall survival and first-month and first-year survival of the patients were evaluated. Patients' age, gender, side, fracture type, treatment method, time between fracture and operation date, presence of femoral arterial calcification and type of anesthesia (regional, general) were recorded.

RESULTS

Of the 481 patients included in the study, 299 were female and 182 were male, and the mean age was calculated as 80.5. Of the patients, 187 were diagnosed with femoral neck fractures and the remaining 294 with pertrochanteric fractures. It was observed that the mortality rate in the first month after surgery was 58 (12%) for both groups, and the mortality rate in the first year was 173 (35.9%) for both groups. The overall postoperative mortality was calculated as 302 (62.7%) for both groups. Femoral arterial calcification was detected in 191 of 481 patients, and femoral arterial calcification was not observed in the remaining 290 patients. Similarly, when both groups were compared in terms of mortality in the first month after surgery, mortality in the first year and overall mortality rates, no significant difference was found between the groups (p>0.05).

CONCLUSION

In our study we showed that femoral arterial calcification has no effect on mortality in acute hip fractures treated by hemiarthroplasty in people over 65 years of age.

Evaluation of Lower Extremity Calcium Score as a Measure of Peripheral Arterial Disease Burden and Amputation Risk

BACKGROUND

The ankle-brachial pressure index (ABI) and toe-brachial pressure index (TBI) are commonly used diagnostic tools for peripheral artery disease (PAD) that are unreliable in the presence of calcified vessels. In this study, we aimed to demonstrate the utility of the lower extremity calcium score (LECS) in addition to ABI and TBI in measuring disease burden and predicting the risk of amputation in patients with PAD.

METHODS

Patients who were evaluated in the vascular surgery clinic at Emory University for PAD and who underwent noncontrast computed tomography of the aorta and lower extremities were included in the study. Aortoiliac, femoral-popliteal, and tibial calcium scores were measured using the Agatston method. ABI and TBI that were obtained within 6 months of the computed tomography scan were noted and divided into categories of PAD severity. Associations between ABI, TBI, and LECS of each anatomic segment were evaluated. Univariate and multivariate ordinal regression analyses were performed to predict the outcome of amputation. Receiver operating characteristic analysis was performed to compare LECS with other variables in its ability to predict amputation.

RESULTS

Fifty patients included in the study cohort were divided into LECS quartiles, with 12-13 patients in each quartile. The highest quartile tended to be older (P = 0.016), had a higher percentage of diabetics (P = 0.034), and had a higher frequency of major amputations (P = 0.004) compared to the other quartiles. Patients in the highest quartile of tibial calcium score were more likely to have stage 3 chronic kidney disease (CKD) or greater (P = 0.011) and also had a higher frequency of amputation (P < 0.005) and mortality (P = 0.041). We found no significant association between each anatomic LECS and ABI/TBI categories. On univariate analysis, CKD (Odds Ratio [OR] 12.92 (95% CI 2.01 to 82.83), P = 0.007), diabetes mellitus (OR 5.47 (95% CI 1.27 to 23.64), P = 0.023), tibial calcium score (OR 6.62 (95% CI 1.79 to 24.54), P = 0.005), and total bilateral calcium score (OR 6.32 (95% CI 1.18 to 33.78), P = 0.031) were associated with increased risk of amputation. On multivariate stepwise ordinal regression, TBI and tibial calcium score were identified as important predictors of amputation, with hyperlipidemia and CKD increasing the overall prediction of the model. On Receiver operating characteristic analysis, the addition of the tibial calcium score (area under the curve 0.94, standard error 0.048) significantly improved the prediction of amputation compared to hyperlipidemia, CKD, and TBI alone (area under the curve 0.82, standard error 0.071, P = 0.022).

CONCLUSIONS

The addition of tibial calcium score to other known PAD risk factors may improve the prediction of amputation in patients with PAD.

Future treatment of vascular calcification in chronic kidney disease

INTRODUCTION

Cardiovascular disease (CVD) is one of the global leading causes of morbidity and mortality in chronic kidney disease (CKD) patients. Vascular calcification (VC) is a major cause of CVD in this population and is the consequence of complex interactions between inhibitor and promoter factors leading to pathological deposition of calcium and phosphate in soft tissues. Different pathological landscapes are associated with the development of VC, such as endothelial dysfunction, oxidative stress, chronic inflammation, loss of mineralization inhibitors, release of calcifying extracellular vesicles (cEVs) and circulating calcifying cells.

AREAS COVERED

In this review, we examined the literature and summarized the pathophysiology, biomarkers and focused on the treatments of VC.

EXPERT OPINION

Even though there is no consensus regarding specific treatment options, we provide the currently available treatment strategies that focus on phosphate balance, correction of vitamin D and vitamin K deficiencies, avoidance of both extremes of bone turnover, normalizing calcium levels and reduction of inflammatory response and the potential and promising therapeutic approaches liketargeting cellular mechanisms of calcification (e.g. SNF472, TNAP inhibitors).Creating novel scores to detect in advance VC and implementing targeted therapies is crucial to treat them and improve the future management of these patients.

Spatial-Temporal Oxygenation Mapping Using a Near-Infrared Optical Scanner: Towards Peripheral Vascular Imaging

Near-infrared spectroscopy (NIRS)-based peripheral perfusion, or microcirculation, can be used to assess the severity of peripheral vascular dysfunction. A low-cost, portable non-contact near-infrared optical scanner (NIROS) was developed for spatio-temporal mapping of tissue oxygenation and perfusion in tissues. In vivo validation studies were carried out on control subjects (n = 3) to assess the ability of NIROS to measure real-time oxygenation changes in response to an occlusion paradigm on the dorsum of the hand. NIROS captured real-time tissue oxygenation changes with 95% correlation when compared to a commercial device. A feasibility peripheral imaging study was performed in a mouse model (n = 5) of chronic kidney disease (CKD) induced vascular calcification to assess differences in microcirculatory peripheral tissue oxygenation. The tissue oxygenation (in terms of oxy-, deoxy-, and total hemoglobin changes) due to the occlusion paradigm was distinctly different prior to (week-6) and after the onset of vascular calcification (week-12) in the murine tails. Future work will involve extensive studies to correlate these microcirculatory tissue oxygenation changes in the peripheral tail to the vascular calcification in the heart.

Use of intravascular lithotripsy in non-coronary artery lesions

BACKGROUND

Intravascular lithotripsy (IVL) is a novel technique increasingly used for plaque modification and endovascular revascularization in patients with severe calcification and peripheral artery disease. However, much of the available literature on IVL is focused on its use in coronary arteries, with relatively limited data on non-coronary artery use.

AIM

To analyze the safety and efficacy of current IVL use in non-coronary artery lesions, as reported in case reports and case series.

METHODS

We searched EMBASE, PubMed, and Reference Citation Analysis databases for case reports and case series on IVL use in peripheral artery disease. We then extracted variables of interest and calculated the mean and proportions of these variables.

RESULTS

We included 60 patients from 33 case reports/case series. Ninety-eight percent of the cases had IVL usage in only one blood vessel, while four had the IVL used in two vessels (2.0%), resulting in 64 Lesions treated with IVL. The mean age of the patients was 73.7 (SD 10.9). IVL was successfully used in severe iliofemoral artery stenosis (51.6%), severe innominate, subclavian, and carotid artery stenosis (26.7% combined), and severe mesenteric vessel stenosis (9.4%). Additionally, IVL was successfully used in severe renal (7.8%) and aortic artery (4.7%) stenosis. There were complications in 12% of the cases, with dissection being the commonest.

CONCLUSION

IVL has successfully used in plaque modification and endovascular revascularization in severely calcified and challenging lesions in the iliofemoral, carotid, subclavian, aorta, renal, and mesenteric vessels. The most severe but transient complications were with IVL use in the aortic arch and neck arteries.

Iliac artery calcification score stratifies mortality risk estimation in patients with chronic limb-threatening ischemia undergoing revascularization

OBJECTIVE

Patients with chronic limb-threatening ischemia (CLTI) are at high risk for adverse limb outcomes and mortality. Using the Vascular Quality Initiative (VQI) prediction model to estimate mortality after revascularization can assist with clinical decision-making. We aimed to improve the discrimination of the 2-year VQI risk calculator by incorporating a common iliac artery (CIA) calcification score based on computed tomography scans.

METHODS

This was a retrospective analysis of patients who underwent infrainguinal revascularization for CLTI from January 2011 to June 2020 and had a computed tomography scan of the abdomen/pelvis 2 years before or up to 6 months after revascularization. CIA calcium morphology, circumference, and length were scored. Bilateral scores were summed for the total calcium burden (CB) score, which was trichotomized (mild, 0-15; moderate, 16-19; severe, 20-22). The VQI CLTI model was used to categorize patients as low, medium, or high risk for mortality.

RESULTS

A total of 131 patients with a mean age of 69±12 years were included in the study, and 86 (66%) were men. CB scores were mild in 52 (40%), moderate in 26 (20%), and severe in 53 (40%) patients. Older patients (P = .0002) and those with coronary artery disease (P = .06) had higher CB scores. Patients with severe CB scores were more likely to undergo infrainguinal bypass compared with those with mild or moderate CB scores (P = .006). The 2-year VQI mortality risk was calculated to be low in 102 (78%), medium in 23 (18%), and high in 6 (4.6%) patients. In the "low-risk" VQI mortality subgroup, 46 (45%) patients had mild, 18 (18%) had moderate, and 38 (37%) had severe CB scores, and patients with severe CB scores had significantly higher risk of mortality compared with those with mild or moderate scores (hazard ratio, 2.5; 95% confidence interval, 1.2-5.1; P = .01). In this "low-risk" VQI mortality subgroup, CB score further stratified the risk of mortality (P = .04).

CONCLUSIONS

Higher total CIA calcification was significantly associated with mortality in patients undergoing infrainguinal revascularization for CLTI, and preoperative assessment of CIA calcification may help with perioperative risk stratification and guide clinical decision making in this population.

Correlation Between Intracranial Calcification and Extracranial Stenosis of the Internal Carotid Artery

Intracranial artery calcification is a marker of vascular atherosclerosis and has a high prevalence worldwide. Both atherosclerosis of the internal carotid artery at the carotid sinus in the neck and intracranial calcification have been associated with ischemic stroke. The relationship between the two has not been well studied. The present study investigated how carotid sinus narrowing could relate to calcification located in the distal intracranial artery at the cavernous carotid. We examined a population not selected for cerebral disease. This retrospective study contained 179 subjects aged 18 years and older from the Hawaii Diagnostic Radiology database. Extracranial internal carotid artery stenosis was determined using the absolute diameter, North American Symptomatic Carotid Endarterectomy Trial, and common carotid artery methods. Calcification was scored using the modified Woodcock method. A positive correlation between intracranial calcification and extracranial carotid stenosis was found using all three methods. Individuals with intracranial calcification were more likely to be older, have a smaller internal carotid artery diameter, and have a greater percent stenosis at the internal carotid artery than those without intracranial artery calcification (p<0.001 for all). These results may help refocus interest in calcification in studies of cerebral vasculature and its correlation with extracranial carotid stenosis.

Medial Arterial Calcification and the Risk of Amputation of Diabetic Foot Ulcer in Patients With Diabetic Kidney Disease

We assessed the risk factors for major amputation of diabetic foot ulcers (DFUs) in patients with diabetic kidney disease (DKD) stages 3b-5. For DFU assessment, in addition to DFU location and presence of infection, ischemia, and neuropathy, vascular calcification was assessed using the medial arterial calcification (MAC) score. Of 210 patients, 26 (12.4%) underwent major amputations. Only the location and extension of DFU, represented by Texas grade differed between the minor and major amputation groups. However, after adjusting for covariates, ulcer location of mid- or hindfoot (vs. forefoot, odds ratio [OR] = 3.27), Texas grades 2 or 3 (vs. grade 0, OR = 5.78), and severe MAC (vs. no MAC, OR = 4.46) was an independent risk factor for major amputation (all P < 0.05). The current use of antiplatelets was a possible protective factor for major amputations (OR = 0.37, P = 0.055). In conclusion, DFU with severe MAC is associated with major amputation in patients with DKD.

Cardiovascular Calcification Heterogeneity in Chronic Kidney Disease

Patients with chronic kidney disease (CKD) exhibit tremendously elevated risk for cardiovascular disease, particularly ischemic heart disease, due to premature vascular and cardiac aging and accelerated ectopic calcification. The presence of cardiovascular calcification associates with increased risk in patients with CKD. Disturbed mineral homeostasis and diverse comorbidities in these patients drive increased systemic cardiovascular calcification in different manifestations with diverse clinical consequences, like plaque instability, vessel stiffening, and aortic stenosis. This review outlines the heterogeneity in calcification patterning, including mineral type and location and potential implications on clinical outcomes. The advent of therapeutics currently in clinical trials may reduce CKD-associated morbidity. Development of therapeutics for cardiovascular calcification begins with the premise that less mineral is better. While restoring diseased tissues to a noncalcified homeostasis remains the ultimate goal, in some cases, calcific mineral may play a protective role, such as in atherosclerotic plaques. Therefore, developing treatments for ectopic calcification may require a nuanced approach that considers individual patient risk factors. Here, we discuss the most common cardiac and vascular calcification pathologies observed in CKD, how mineral in these tissues affects function, and the potential outcomes and considerations for therapeutic strategies that seek to disrupt the nucleation and growth of mineral. Finally, we discuss future patient-specific considerations for treating cardiac and vascular calcification in patients with CKD-a population in need of anticalcification therapies.

Treatment of Difficult, Calcified Lesions: Plaque Modification Strategies

Endovascular management of peripheral arterial disease is continually evolving. Most changes focus on addressing the challenges that hinder optimal patient outcomes; one of the most significant is how to best treat calcified lesions. Hardened plaque results in a variety of technical issues including impaired device delivery, decreased luminal revascularization, poor stent expansion, heightened risk of in-stent stenosis or thrombosis, and increased procedural time and cost. For this reason, plaque modification devices have been developed to mitigate this issue. This paper will describe these strategies and provide the reader with an overview of devices that can be used to treat chronically hardened lesions.

Intravascular Lithotripsy in Calcified Peripheral Lesions: Single-Center JEN-Experience

Peripheral artery disease (PAD) shows increasing need for revascularization therapy. Interventional success in calcified lesions is limited. Here, intravascular lithotripsy (IVL), modifying intimal and medial calcium, is a promising treatment approach. A single-center, prospective all-comers registry for patients undergoing peripheral IVL was established to examine treatment success in PAD with severe vessel calcification. Periprocedural safety events as well as short-term and intermediate follow-up clinical data were evaluated. Between December 2018 and January 2021 all consecutive patients receiving peripheral lithotripsy at our center were analyzed. Clinical and angiographic data were evaluated. Angiographic images were analyzed using a semiautomatic software for quantitative vessel analysis. Eighty-five lesions in 61 limbs were treated with IVL in 51 patients presenting with Rutherford classes 2 to 5. Most lesions (68%) were localized in the superficial femoral artery. Mean calcified lesion length was 102.5 mm (10-390 mm), with a median peripheral arterial calcium score of 3, indicating a highly calcified status. In 58% of the patients, IVL was used as a stand-alone therapy. IVL resulted in a mean acute luminal gain of 2.6 ± 0.9 mm, resulting in stenosis reduction by 42.1 ± 15%. Mean ankle brachial index (ABI) improved significantly from 0.6 to 0.8 ( p  < 0.0001) on day 1 after the intervention and remained stable at 6 months. This large real-world data of peripheral IVL reports compelling safety in a complex patient cohort. For the first time, clinical follow-up data demonstrated a sustained significant improvement in ABI after 6 months.

Medial artery calcification in peripheral artery disease

Medial artery calcification (MAC) is a distinct, highly regulated process that is often identified in small and mid-sized arteries of the lower extremities. It is associated with advanced age, diabetes, and chronic kidney disease. MAC often occurs in conjunction with atherosclerotic occlusive disease in lower extremity arteries, and when seen together or in isolation, long-term limb outcomes are negatively affected. In patients with peripheral artery disease (PAD), the extent of MAC independently correlates with major amputation and mortality rates, and it predicts poor outcomes after endovascular interventions. It is associated with increased arterial stiffness and decreased pedal perfusion. New endovascular methods aimed at treating calcified lower-extremity lesions may improve our ability to treat patients with limb-threatening ischemia. Although recent developments have increased our understanding of the mechanisms contributing to MAC, further investigations are needed to understand the role of medial calcification in PAD, and to develop strategies aimed at improving patient outcomes.

Vessel-by-vessel analysis of lower extremity 18F-NaF PET/CT imaging quantifies diabetes- and chronic kidney disease-induced active microcalcification in patients with peripheral arterial disease

BACKGROUND

Positron emission tomography (PET)/computed tomography (CT) imaging with fluorine-18 (¹⁸F)-sodium fluoride (NaF) provides assessment of active vascular microcalcification, but its utility for evaluating diabetes mellitus (DM)- and chronic kidney disease (CKD)-induced atherosclerosis in peripheral arterial disease (PAD) has not been comprehensively evaluated. This study sought to use ¹⁸F-NaF PET/CT to quantify and compare active microcalcification on an artery-by-artery basis in healthy subjects, PAD patients with or without DM, and PAD patients with or without CKD. Additionally, we evaluated the contributions of DM, CKD, statin use and established CT-detectable calcium to ¹⁸F-NaF uptake for each lower extremity artery.

METHODS

PAD patients (n = 48) and healthy controls (n = 8) underwent lower extremity ¹⁸F-NaF PET/CT imaging. Fused PET/CT images guided segmentation of arteries of interest (i.e., femoral-popliteal, anterior tibial, tibioperoneal trunk, posterior tibial, and peroneal) and quantification of ¹⁸F-NaF uptake. ¹⁸F-NaF uptake was assessed for each artery and compared between subject groups. Additionally, established calcium burden was quantified for each artery using CT calcium mass score. Univariate and multivariate analyses were performed to evaluate DM, CKD, statin use, and CT calcium mass as predictors of ¹⁸F-NaF uptake in PAD.

RESULTS

PAD patients with DM or CKD demonstrated significantly higher active microcalcification (i.e., ¹⁸F-NaF uptake) for all arteries when compared to PAD patients without DM or CKD. Univariate and multivariate analyses revealed that concomitant DM or CKD was associated with increased microcalcification for all arteries of interest and this increased disease risk remained significant after adjusting for patient age, sex, and body mass index. Statin use was only associated with decreased microcalcification for the femoral-popliteal artery in multivariate analyses. Established CT-detectable calcium was not significantly associated with ¹⁸F-NaF uptake for 4 out of 5 arteries of interest.

CONCLUSIONS

¹⁸F-NaF PET/CT imaging quantifies vessel-specific active microcalcification in PAD that is increased in multiple lower extremity arteries by DM and CKD and decreased in the femoral-popliteal artery by statin use. ¹⁸F-NaF PET imaging is complementary to and largely independent of established CT-detectable arterial calcification. ¹⁸F-NaF PET/CT imaging may provide an approach for non-invasively quantifying vessel-specific responses to emerging anti-atherogenic therapies or CKD treatment in patients with PAD.

Quiescent-Interval Single-Shot Magnetic Resonance Angiography May Outperform Carbon-Dioxide Digital Subtraction Angiography in Chronic Lower Extremity Peripheral Arterial Disease

Nephroprotective imaging in peripheral arterial disease (PAD) is often crucial. We compared the diagnostic performance of non-contrast Quiescent-interval single-shot magnetic resonance angiography (QISS MRA) and carbon-dioxide digital subtraction angiography (CO2 DSA) in chronic lower extremity PAD patients. A 19-segment lower extremity arterial model was used to assess the degree of stenosis (none, <50%, 50−70%, >70%) and the image quality (5-point Likert scale: 1-non-diagnostic, 5-excellent image quality). Intra-class correlation coefficient (ICC) was calculated for inter-rater reliability. Diagnostic accuracy and interpretability were evaluated using CO2 DSA as a reference standard. 523 segments were evaluated in 28 patients (11 male, mean age: 71 ± 9 years). Median and interquartile range of subjective image quality parameters for QISS MRA were significantly better compared to CO2 DSA for all regions: (aortoiliac: 4 [4−5] vs. 3 [3−4]; femoropopliteal: 4 [4−5] vs. 4 [3−4]; tibioperoneal: 4 [3−5] vs. 3 [2−3]; all regions: 4 [4−5] vs. 3 [3−4], all p < 0.001). QISS MRA out-performed CO2 DSA regarding interpretability (98.3% vs. 86.0%, p < 0.001). Diagnostic accuracy parameters of QISS MRA for the detection of obstructive luminal stenosis (70%<) as compared to CO2 DSA were as follows: sensitivity 82.6%, specificity 96.9%, positive predictive value 89.1%, negative predictive value 94.8%. Regarding the degree of stenosis, interobserver variability for all regions was 0.97 for QISS MRA and 0.82 for CO2 DSA. QISS MRA proved to be superior to CO2 DSA regarding subjective image quality and interpretability for the imaging of chronic lower extremity PAD.

Automatic measurement of vascular calcifications in patients with aorto-iliac occlusive disease to predict the risk of re-intervention after endovascular repair

OBJECTIVE

There is currently a lack of consensus and tools to easily measure vascular calcification using computed tomography angiography (CTA). The aim of this study was to develop a fully automatic software to measure calcifications and to evaluate the interest as predictive factor in patients with aorto-iliac occlusive disease.

METHODS

This study retrospectively included 171 patients who had endovascular repair of an aorto-iliac occlusive lesion at the University Hospital of Nice between January 2011 and December 2019. Calcifications volumes were measured from CT-angiography (CTA) using an automatic method consisting in 3 sequential steps: image pre-processing, lumen segmentation using expert system and deep learning algorithms and segmentation of calcifications. Calcification volumes were measured in the infrarenal abdominal aorta and the iliac arterial segments, corresponding to the common and the external iliac arteries.

RESULTS

Among 171 patients included with a mean age of 65 years, the revascularization was performed on the native external and internal iliac arteries in respectively: 83 patients (48.5%); 107 (62.3%) and 7 (4.1%). The mean volumes of calcifications were 2759 mm³ in the infrarenal abdominal aorta, 1821 mm³ and 1795 mm³ in the right and left iliac arteries. For a mean follow up of 39 months, TLR was performed in 55 patients (32.2%). These patients had higher volume of calcifications in the right and left iliac arteries, compared with patients who did not have a re-intervention (2274 mm³ vs 1606 mm³, p=0.0319 and 2278 vs 1567 mm³, p=0.0213).

CONCLUSION

The development of a fully automatic software would be useful to facilitate the measurement of vascular calcifications and possibly better inform the prognosis of patients.

A case of critical ischemia of the lower limbs: critical elements and possible medico-legal implications

Peripheral arterial disease (PAD) is an atherosclerotic process that causes stenosis and occlusion of non-cerebral and non-coronary arteries. Critical ischemia of the lower limbs is the most advanced and severe state of arterial disease. The purpose of this work is to underline the importance of a timely diagnostic-therapeutic framework in case of critical ischemia of the lower limbs, through a precise, coordinated, and multidisciplinary teamwork. A significant example is represented by the presentation of a clinical case that came to our observation following a request for compensation and which required an adequate evaluation in the medical-legal field. This work will make possible to clarify any profiles of medical professional responsibility, with specific reference to the predictability and preventability of the unfavorable events that have occurred, and which have led to a progressive worsening of the patient's clinical condition, which then resulted in the amputation of the lower limb, associated to organic deterioration and progressive complete permanent disability. In these cases, the collection of semeiological data must be careful, meticulous, and completed by suitable instrumental investigations. These data, with the exhaustive compilation of the medical record, play a decisive role even in the presence of adverse events and/or infrequent complications, in order to demonstrate from a medico-legal point of view that despite the implementation of all precautions codified by the specialized discipline, the adverse event, however foreseeable, is not always concretely preventable and therefore avoidable, being included in the non-negligent "complication" and not necessarily attributable to professional responsibility.

Calcium Score Predicts Mortality After Revascularization in Critical Limb Ischemia

PURPOSE

The calcium score is a measure of vessel wall calcification and has clinical applications when studied in different vascular beds. The presence of vascular calcification in the arteries of the lower limbs is very common in patients with peripheral arterial disease; however, its relationship with the postoperative outcomes in patients undergoing lower limb revascularization is still poorly studied. The aim of this study is to evaluate association between the calcium score of lower limbs and the postoperative outcomes in patients with peripheral arterial disease undergoing revascularization procedures.

METHODOLOGY

We retrospectively analyzed 88 lower limb revascularization procedures in 72 patients with critical limb ischemia who had enhanced computed tomography for preoperative evaluation. The calcium score was calculated, from the angiographic phase of preoperative computed tomography, in the segments of the aorta, iliac, femoropopliteal, and infrapopliteal. It was also calculated the calcium score of the operated limb, and the total calcium score using a standardized method. The outcomes evaluated were the occurrence of acute myocardial infarction, amputation, patency, technical success, and death from any cause. Patients were followed up through a 12 month period.

RESULTS

Among the 88 procedures performed, 31 (43.1%) lesions were classified as Trans-Atlantic Inter-Society Consensus Document II D. There were 66 (75%) endovascular procedures, 16 (18.2%) open surgery, and 6 (6.8%) hybrid interventions. No statistically significant relationship was found between the calcium score of the segments (aorta, iliac, femoropopliteal, infrapopliteal, the operated limb, and total calcium score) and the outcomes of acute myocardial infarction, amputation, patency, and technical success in any of the periods analyzed. The calcium score of the operated limb was higher in patients who died within 30 days and 6 months (6571 vs 2590.6; p=0.026) and (5227.8 vs 2335.3; p=0.036).

CONCLUSION

A standardized calcium score calculation method with the angiographic phase of the computed tomography is feasible and reproducible. Higher values of the calcifications of the operated limb are related to a greater chance of death in the postoperative period. The calcium score of the operated limb can be considered as a marker of clinical severity and prognosis in this group of patients.

Outcomes of Endovascular Aneurysm Repair with Adjunctive Stenting

OBJECTIVE

Endovascular aneurysm repair is the standard of care for abdominal aortic aneurysm repair, however data regarding adjunctive stenting at the time of endovascular aneurysm repair (EVAR) are limited. The study aims to evaluate outcomes of patients undergoing EVAR with and without adjunctive stenting.

METHODS

Patients undergoing EVAR with stenting (EVAR-S) and without stenting (EVAR) (2008 to 2017) were selected from Cerner HealthFacts® database using ICD-9 diagnosis and procedure codes. Chi-square analysis and multivariable logistic regression were used to evaluate the association of patient characteristics with medical and vascular outcomes.

RESULTS

4,957 patients undergoing EVAR procedures were identified (3,816 EVAR and 1,141 EVAR-S). Demographic analysis revealed that patients who underwent EVAR-S had higher Charlson comorbidity scores (2.35 vs. 2.13, p = .0001). EVAR-S was associated with a greater frequency of vascular complications such as thrombolysis/percutaneous thrombectomy (0.9% vs. 0.2%; p < .0004). There were no differences seen in access complications between EVAR and EVAR-S. Multivariable analysis revealed that EVAR-S was associated with prolonged length of stay (OR 1.37, 95% CI 1.03-1.82), readmission < 30 days (OR 1.36, 95% CI 1.11-1.68), major adverse cardiac events (OR 1.59, 95% CI 1.09-2.32), respiratory complications (OR 1.47, 95% CI 1.16-1.88) and renal failure (OR 1.57, 95% CI 1.16-2.11).

CONCLUSIONS

Endovascular aneurysm repair with adjunctive stenting (EVAR-S) was associated with vascular complications requiring reintervention, although the overall rate was very low. As well, readmission within 30 days, cardiac complications, respiratory problems and renal failure were more likely when compared to standard EVAR. The need for adjunctive stenting acts as a marker for an overall sicker and more complex population, not just in terms of vascular complications but across all medical complications as well. Staging the procedure may be helpful in terms of spreading out the operative risk into smaller portions. Furthermore, consideration of a non-operative strategy should be discussed with the patient if the risk of the procedure outweighs the risk of aneurysm rupture in high-risk groups.

Hand osteomyelitis in arterial calcification, diabetes mellitus and end-stage renal failure: a comparison of 210 cases over 12 years

We present 210 patients with hand osteomyelitis in 246 rays over 12 years, including detailed analysis of 29 patients in this cohort with digital artery calcification evident on plain X-ray. Overall 71 patients had diabetes mellitus and/or end-stage renal failure, including 28 of 29 patients with calcification. In the calcification group, 17 patients had ipsilateral arteriovenous fistulae, five had steal syndrome and 15 had digital ulceration or skin necrosis. Compared with 181 controls, patients with calcification had more affected bones, polymicrobial infections, surgical procedures, phalanges and digits amputated and had higher mortality at 1 year (12 of 29) and 5 years (20 of 29), as a result of comorbidities. Absence of calcification in 43 patients with diabetes and/or end-stage renal failure was associated with better outcomes on all the above parameters. Early amputation to maximize disease-free survival may be appropriate for patients with hand osteomyelitis and arterial calcification.Level of evidence: IV.

Calcification patterns in femoral and carotid atheromatous plaques: A comparative morphometric study

This comparative study was designed to focus on the mineral patterns in human atherosclerotic plaques based on quantitative measurements of calcium deposits through the morphometric method. A total of 101 atherosclerotic plaques were harvested by conventional transluminal angioplasty from the carotid artery (CA) and different segments of the femoral-popliteal axis (FPA), fixed in formalin and sent for histological processing. The histological grade of the atherosclerotic plaque and the calcification pattern were evaluated, followed by a morphometric analysis of the mineral deposits. Regarding the localization, the advanced plaques (VII and VIII types) developed predominantly at the level of the superficial femoral artery (SFA) compared to the CA (P<0.001). This significant difference was maintained even if they were divided into low grade (IV and V) and high grade categories (VI, VII and VIII) (P<0.05). Compared with that in the carotid plaques, in the FPA plaques the mineralized surface increased in parallel with the narrowing of the vascular lumen diameter. The image analysis of the total pathological calcification score (pCS) showed a significant difference between the CA plaques and distal SFA (dSFA) plaques (P=0.038) and between the proximal SFA (pSFA) and dSFA plaques (P=0.013). In the case of the simple nodular pattern, calcification occupied significantly larger areas in the plaques developed in the dSFA and popliteal artery (PA) in comparison with the CA plaques (P=0.0007 and P=0.0009). pCSs calculated in plaques with extensive calcification pattern showed a lower value in the CA vs. the pSFA plaques (P=0.004). A less pronounced, but significant difference was observed between the pCS of pSFA and dSFA plaques (P=0.017). Femoral and carotid plaques exhibited different morphology and tendency for calcification. In parallel with the narrowing of the vascular lumen diameter, the mineralized surface increased at the level of different FPA segments. These results suggest that the mechanism is site-specific, and wall structure-dependent.

Recovery of limb perfusion and function after hindlimb ischemia is impaired by arterial calcification

Medial artery calcification results from deposition of calcium hydroxyapatite crystals on elastin layers, and osteogenic changes in vascular smooth muscle cells. It is highly prevalent in patients with chronic kidney disease, diabetes, and peripheral artery disease (PAD), and when identified in lower extremity vessels, it is associated with increased amputation rates. This study aims to evaluate the effects of medial calcification on perfusion and functional recovery after hindlimb ischemia in rats. Medial artery calcification and acute limb ischemia were induced by vitamin D3 (VitD3 ) injection and femoral artery ligation in rats. VitD3 injection robustly induced calcification in the medial layer of femoral arteries in vivo. Laser Doppler perfusion imaging revealed that perfusion decreased and then partially recovered after hindlimb ischemia in vehicle-injected rats. In contrast, VitD3 -injected rats showed markedly impaired recovery of perfusion following limb ischemia. Accordingly, rats with medial calcification showed worse ischemia scores and delayed functional recovery compared with controls. Immunohistochemical and histological staining did not show differences in capillary density or muscle morphology between VitD3 - and vehicle-injected rats at 28 days after femoral artery ligation. The evaluation of cardiac and hemodynamic parameters showed that arterial stiffness was increased while cardiac function was preserved in VitD3 -injected rats. These findings suggest that medial calcification may contribute to impaired perfusion in PAD by altering vascular compliance, however, the specific mechanisms remain poorly understood. Reducing or slowing the progression of arterial calcification in patients with PAD may improve clinical outcomes.

Different Lower Extremity Arterial Calcification Patterns in Patients with Chronic Limb-Threatening Ischemia Compared with Asymptomatic Controls

Objectives: The most severe type of peripheral arterial disease (PAD) is critical limb-threatening ischemia (CLI). In CLI, calcification of the vessel wall plays an important role in symptoms, amputation rate, and mortality. However, calcified arteries are also found in asymptomatic persons (non-PAD patients). We investigated whether the calcification pattern in CLI patients and non- PAD patients are different and could possibly explain the symptoms in CLI patients. Materials and Methods: 130 CLI and 204 non-PAD patients underwent a CT of the lower extremities. This resulted in 118 CLI patients (mean age 72 ± 12, 70.3% male) that were age-matched with 118 non-PAD patients (mean age 71 ± 11, 51.7% male). The characteristics severity, annularity, thickness, and continuity were assessed in the femoral and crural arteries and analyzed by binary multiple logistic regression. Results: Nearly all CLI patients have calcifications and these are equally frequent in the femoropopliteal (98.3%) and crural arteries (97.5%), while the non-PAD patients had in just 67% any calcifications with more calcifications in the femoropopliteal (70.3%) than in the crural arteries (55.9%, p < 0.005). The crural arteries of CLI patients had significantly more complete annular calcifications (OR 2.92, p = 0.001), while in non-PAD patients dot-like calcifications dominated. In CLI patients, the femoropopliteal arteries had more severe, irregular/patchy, and thick calcifications (OR 2.40, 3.27, 1.81, p ≤ 0.05, respectively) while in non-PAD patients, thin continuous calcifications prevailed. Conclusions: Compared with non-PAD patients, arteries of the lower extremities of CLI patients are more frequently and extensively calcified. Annular calcifications were found in the crural arteries of CLI patients while dot-like calcifications were mostly present in non-PAD patients. These different patterns of calcifications in CLI point at different etiology and can have prognostic and eventually therapeutic consequences.

Does Presence of Femoral Arterial Calcification Have an Effect on Postoperative Complication and Mortality in Patients With Hip Fracture?

Introduction In this study, we investigated the relationship between femoral arterial calcification on preoperative hip radiography and post-operative complications and all-time mortality rates in patients with hip fracture >65 years old. Methods This retrospective study was conducted by evaluating the records of patients who were operated for hip fractures. All patients were divided into two groups according to the presence of lower extremity arterial calcification (LEAC) at the femoral artery which was diagnosed using the hip radiograph. The patients with and without the presence of LEAC were assigned as groups 1 and 2, respectively. A multivariate Cox algorithm was applied to recognize whether this radiological factor is independently associated with survival. Results The study included 530 patients (540 hips; 191 males and 339 females) with an average age of 80.8 ± 7.6 years. In the study after 24.8±19.9 months (range:0-65 months) follow-up period, 336 (63.3%) patients had expired. Conversely, 194 (36.7%) patients are surviving. Survival rates at one month and one year after surgery were 89.5% and 65.7%, respectively. 234 of 540 hips (230 patients) have LEAC on the femoral artery. The survival rate at one month, one year, and overall survival were significantly higher in patients with LEAC. The postoperative infection rate was also two times higher in patients with LEAC than without LEAC (p = 0.021). Multivariate analysis demonstrated that age, treatment modality (hemiarthroplasty), and the presence of femoral arterial calcification were independently associated with poor overall survival. Conclusions In our study, we found that the presence of femoral arterial calcification on the affected side of the hip identified on hip radiograph was independently associated with poor one month, one year, and overall survival as the patients had 1.5 times higher mortality rate. Additionally, a significant correlation was found between age and survival of patients with hip fracture, especially patients >80 years old.

Pilot study of contrast-free MRI reveals significantly impaired calf skeletal muscle perfusion in diabetes with incompressible peripheral arteries

Patients with diabetes mellitus (DM) are more likely to have densely calcified lesions in the below-the-knee tibial arteries. However, the relationship between peripheral arterial calcification and local skeletal muscle perfusion has not been explored. Thirty subjects were prospectively recruited into three groups in this pilot study: (1) Non-DM: 10 people without DM; (2) DM, ABI < 1.3: 10 people with DM and normal ankle-brachial index (ABI) (0.9-1.3); and (3) DM, ABI ⩾ 1.3: 10 people with DM and ABI ⩾ 1.3. All subjects underwent calf perfusion measurements at rest and during an isometric plantarflexion contraction exercise within the magnetic resonance imaging (MRI) system. The noncontrast MRI techniques were applied to quantitatively assess skeletal muscle blood flow (SMBF) and oxygen extraction fraction (SMOEF) in medial gastrocnemius and soleus muscles. Both SMBF and SMOEF reserves were calculated as the ratio of the exercise value to the resting value. Exercise SMBF and SMOEF values in the medial gastrocnemius muscle were lower in the two DM groups than in the non-DM group (p < 0.05). The SMBF reserve in medial gastrocnemius was significantly lower in the DM, ABI ⩾ 1.3 group compared to the DM, ABI < 1.3 group (p < 0.05). This study demonstrates that people with DM and calcified arteries had lower perfusion in gastrocnemius muscle compared to those without DM and those with DM and a normal ABI.

Successful Peripheral Vascular Intervention in Patients with High-risk Comorbidities or Lesion Characteristics

PURPOSE OF REVIEW

Certain comorbidities and lesion characteristics are associated with increased risk for procedural complications, limb events, and cardiovascular events following peripheral vascular intervention (PVI) in patients with peripheral arterial disease (PAD). The purpose of this review is to provide an overview of high-risk modifiable and unmodifiable patient characteristics and its relative impact on clinical outcomes such as amputation risk and mortality. Furthermore, general approaches to potentially mitigating these risks through pre-intervention planning and use of modern devices and techniques are discussed.

RECENT FINDINGS

Diabetes, tobacco use, and older age remain strong risk factors for the development of peripheral arterial disease. Recent data highlight the significant risk of polyvascular disease on major limb and cardiac events in advanced PAD, and ongoing studies are assessing this risk specifically after PVI. Challenging lesion characteristics such as calcified disease and chronic total occlusions can be successfully treated with PVI by utilizing novel devices (e.g., intravascular lithotripsy, re-entry devices) and techniques (e.g., subintimal arterial "flossing" with antegrade-retrograde intervention). Understanding high-risk patient comorbidities and lesion characteristics will improve our ability to counsel and manage patients with advanced PAD. Continued device innovation and novel techniques will aid in procedural planning for successful interventions to improve clinical outcomes.

Diabetes, Lipids, and CV Risk

PURPOSE OF REVIEW

Diabetes is often associated with diabetic dyslipidemia. Both hyperglycemia and disorders of lipid metabolism strongly contribute to development of atherosclerosis, the crucial factor of cardiovascular disease. The aim of the manuscript is to summarize possible treatment to reduce cardiovascular risk.

RECENT FINDINGS

Maximal cardiovascular risk reduction is maintained by targeting more pathologic disturbances together. While antihypertensive treatment has not changed much recently, novel PCSK9 inhibitors have significantly improved management of dyslipidemia. Similarly, modern antihyperglycemic agents (SGLT2 inhibitors and GLP-1 receptor agonists) show both significant metabolic effects and cardiovascular benefits. Diabetes treatment is no longer glucocentric. Apart from glucose management, there are effective pharmacologic tools for significant reduction of cardiovascular risk.