Medial Arterial Calcification Research Articles

Orphan Nuclear Receptor NR4A3 Promotes Vascular Calcification via Histone Lactylation.

Medial arterial calcification is a chronic systemic vascular disorder distinct from atherosclerosis and is commonly observed in patients with chronic kidney disease, diabetes, and aging individuals. We previously showed that NR4A3 (nuclear receptor subfamily 4 group A member 3), an orphan nuclear receptor, is a key regulator in apo (apolipoprotein) A-IV-induced atherosclerosis progression; however, its role in vascular calcification is poorly understood. We generated NR4A3-/- mice and 2 different types of medial arterial calcification models to investigate the biological roles of NR4A3 in vascular calcification. RNA-seq was performed to determine the transcriptional profile of NR4A3-/- vascular smooth muscle cells under β-glycerophosphate treatment. We integrated Cleavage Under Targets and Tagmentation analysis and RNA-seq data to further investigate the gene regulatory mechanisms of NR4A3 in arterial calcification and target genes regulated by histone lactylation. NR4A3 expression was upregulated in calcified aortic tissues from chronic kidney disease mice, 1,25(OH)2VitD3 overload-induced mice, and human calcified aorta. NR4A3 deficiency preserved the vascular smooth muscle cell contractile phenotype, inhibited osteoblast differentiation-related gene expression, and reduced calcium deposition in the vasculature. Further, NR4A3 deficiency lowered the glycolytic rate and lactate production during the calcification process and decreased histone lactylation. Mechanistic studies further showed that NR4A3 enhanced glycolysis activity by directly binding to the promoter regions of the 2 glycolysis genes ALDOA and PFKL and driving their transcriptional initiation. Furthermore, histone lactylation promoted medial calcification both in vivo and in vitro. NR4A3 deficiency inhibited the transcription activation and expression of Phospho1 (phosphatase orphan 1). Consistently, pharmacological inhibition of Phospho1 attenuated calcium deposition in NR4A3-overexpressed vascular smooth muscle cells, whereas overexpression of Phospho1 reversed the anticalcific effect of NR4A3 deficiency in vascular smooth muscle cells. Taken together, our findings reveal that NR4A3-mediated histone lactylation is a novel metabolome-epigenome signaling cascade mechanism that participates in the pathogenesis of medial arterial calcification.

Smooth muscle cell-specific matrix metalloproteinase 3 deletion reduces osteogenic transformation and medial artery calcification.

Vascular calcification is highly prevalent in atherosclerosis, diabetes, and chronic kidney disease. It is associated with increased morbidity and mortality in patients with cardiovascular disease. Matrix metalloproteinase 3 (MMP-3), also known as stromelysin-1, is part of the large matrix metalloproteinase family. It can degrade extracellular matrix components of the arterial wall including elastin, which plays a central role in medial calcification. In this study, we sought to determine the role of MMP-3 in medial calcification. We found that MMP-3 was increased in rodent models of medial calcification as well as in vascular smooth muscle cells (SMCs) cultured in a phosphate calcification medium. It was also highly expressed in calcified tibial arteries in patients with peripheral arterial disease (PAD). Knockdown and inhibition of MMP-3 suppressed phosphate-induced SMC osteogenic transformation and calcification, whereas the addition of a recombinant MMP-3 protein facilitated SMC calcification. In an ex vivo organ culture model and a rodent model of medial calcification induced by vitamin D3, we found that MMP-3 deficiency significantly suppressed medial calcification in the aorta. We further found that medial calcification and osteogenic transformation were significantly reduced in SMC-specific MMP-3-deficient mice, suggesting that MMP-3 in SMCs is an important factor in this process. These findings suggest that MMP-3 expression in vascular SMCs is an important regulator of medial calcification and that targeting MMP-3 could provide a therapeutic strategy to reduce it and address its consequences in patients with PAD.

Risk Factors for Medial and Intimal Intracranial Internal Carotid Artery Calcification in Men and Women with Cardiovascular Disease: The UCC-SMART Study

Introduction: Calcifications of the intracranial internal carotid artery (iICA) can lead to an increased risk for stroke. Two types of iICA calcification are known: those affecting the tunica intima or the tunica media. In extracranial arteries, risk factors and calcification patterns are different in women and men, but little is known regarding the iICA. In this study, we aimed to identify sex-specific risk profiles and medications associated to intimal and medial iICA calcification in patients with cardiovascular disease (CVD). Methods: Participants of the UCC-SMART cohort undergoing a non-contrast head CT within 6 months from the study inclusion were considered (n = 475). Intimal or medial iICA calcification pattern was assessed using a previously histology-validated method. Sex-stratified associations between calcification pattern and cardiovascular risk factors, laboratory parameters, and medication use were calculated using Poisson regression analysis with robust standard errors. Results: Two hundred and four women and 271 men (age range 24–79 years) were included. 45.4% of men and 34.8% of women showed intimal iICA calcification, while 28.4% of men and 24.0% of women showed medial iICA calcification. Minimal or no iICA calcification was observed in 26.2% of men and in 41.2% of women (reference group). Older age was associated with both calcification patterns in women and men. In women, use of vitamin K antagonists and lipid-lowering drugs was associated to medial calcification, while systolic blood pressure and glucose levels were associated to intimal calcification. In men, current smoking was associated to intimal calcification. Conclusions: Women and men with CVD show differences in risk profiles and medication use associated to intimal and medial iCA calcification.

Early hemodynamics after tibial transverse transport in patients with nonarterial stenosis and arterial stenosis diabetic foot.

The diagnosis of peripheral arteriopathy in the diabetic foot is complicated by diabetes and its advanced complications. It has been found that diabetic foot can be categorized into arterial stenosis and non-arterial stenosis, both of which have significant differences in hemodynamic characteristics. To evaluate the early hemodynamic changes in diabetic foot patients with nonarterial stenosis and arterial stenosis treated by tibial transverse transport (TTT) using high-frequency color Doppler ultrasonography (HFCDU) and a laser Doppler flowmeter. Twenty-five patients with Wagner grades 3-5 diabetic foot ulcers were treated with TTT, and the wound healing time and rate were recorded. Patients were grouped according to the results of preoperative lower-extremity ultrasonography. Cases with ≥ 50% stenosis in any of the femoral, popliteal, posterior tibial, anterior tibial, and peroneal arteries of the affected limb were classified as the arterial stenosis group (n = 16); otherwise, they were classified as the nonarterial stenosis group (n = 9). Before and one month after surgery, HFCDU was used to evaluate the degree of lower limb artery lesions and hemodynamic changes in patients. The degree of femoral-popliteal atherosclerotic stenosis, the degree of vascular stenosis and occlusion of the lower-knee outflow tract, and the degree of medial arterial calcification were scored; the three scores were added together to obtain the total score of lower extremity arteriopathy. PeriScanPIM3, a laser Doppler flowmeter system, was used to detect alterations in plantar microcirculation before and 1 mo after surgery. Wound healing and hemodynamic indices were compared between the two groups. The wound healing time of the diabetic foot was significantly shorter in the nonarterial stenosis group than in the arterial stenosis group (47.8 ± 13 vs 85.8 ± 26, P < 0.05), and the wound healing rate of both groups was 100%. The preoperative total lower extremity arteriopathy scores were lower in the nonarterial stenosis group than those in the arterial stenosis group (18.89 ± 8.87 vs 24.63 ± 3.52, P < 0.05). The nonarterial stenosis group showed higher preoperative popliteal artery (POA) blood flow than the arterial stenosis group (204.89 ± 80.76 cc/min vs 76.75 ± 48.49 cc/min, P < 0.05). Compared with the baseline (before surgery), the postoperative POA blood flow of the affected limb in the nonarterial stenosis group decreased one month after surgery (134.11 ± 47.84 cc/min vs 204.89 ± 80.76 cc/min, P < 0.05), while that in the arterial stenosis group increased (98.44 ± 30.73 cc/min vs 61.69 ± 21.70 cc/min, P < 0.05). Although the POA blood flow in the arterial stenosis group was obviously improved one month after surgery, it was still lower than that in the nonarterial stenosis group (98.44 ± 30.73 cc/min vs 134.11 ± 47.84 cc/min, P < 0.05). The nonarterial stenosis group had higher preoperative plantar microcirculation than the arterial stenosis group (56.1 ± 9.2 vs 33.2 ± 7.5, P < 0.05); compared with the baseline, the plantar microcirculation in the arterial stenosis group was significantly improved one month after surgery (51.9 ± 7.2, P < 0.05), while that in the nonarterial stenosis group was reduced (35.9 ± 7.2, P < 0.05). Based on preoperative HFCDU findings, diabetic foot patients can be divided into two categories: Those with nonarterial stenosis and those with arterial stenosis, with obvious differences in hemodynamic changes in the early postoperative period between them. In the early stage after TTT, the blood flow volume and velocity and the plantar microcirculation perfusion of the affected limb of the diabetic foot with nonarterial stenosis decreased compared with the baseline, while those of the diabetic foot with arterial stenosis improved significantly compared with the baseline, although both had smoothly healed diabetic foot ulcers.

Better Detection of Peripheral Arterial Disease with Toe-Brachial Index Compared to Ankle-Brachial Index among Taiwanese Patients with Diabetic Kidney Disease

Background: Ankle-brachial index (ABI) is a simple method for diagnosing peripheral artery disease (PAD) but has limited reliability in patients with diabetes mellitus (DM) because of medial artery calcification. Our study aims to investigate whether the toe brachial index (TBI) or the cardio-ankle vascular index (CAVI) has a better detection over the ABI for diagnosing PAD in diabetic kidney disease (DKD). Materials and Methods: A cohort of 368 patients (mean age 68.59 ± 13.14 years, 190 males and 178 females) with type 2 DM underwent ABI, TBI, and CAVI measurements at our outpatient clinic. Results: Of all enrolled patients, the TBI is significant in evaluating PAD, especially in patients whose chronic kidney disease (CKD) stage 3a with adjusted odds ratio (AOR) = 6.50, 95% confidence interval (CI) 1.63–25.97, p = 0.0080, stage 3b AOR = 7.47, 95% CI 1.52–36.81, p = 0.0135, and stage 4–5 AOR = 20.13, 95% CI 1.34–94.24, p = 0.0116. CAVI is also significant in CKD stage 1 with AOR = 0.16, 95% CI 0.03–0.77, p = 0.0223, stage 2 with AOR = 0.18, 95% CI 0.04–0.74, p = 0.0180, and stage 3a AOR = 0.31, 95% CI 0.10–0.93, p = 0.0375. Conclusion: TBI has a better yield of detection of PAD compared to ABI among Taiwanese patients with DKD. CAVI may play a role in the early stage of DKD.

Diagnostic accuracy of the maximal systolic acceleration to detect peripheral arterial disease

BackgroundDiagnosing peripheral arterial disease (PAD) can be challenging owing to medial arterial calcification (MAC) in patients with diabetes mellitus (DM) and chronic kidney disease (CKD). Current bedside tests, such as the ankle-brachial index and toe-brachial index, are often insufficient. The maximal systolic acceleration (ACCmax) is a velocimetric Doppler-derived parameter and could be a new promising test in the diagnostic workup of these patients. The primary aim of this study was to evaluate the diagnostic performance of the ACCmax to detect PAD. MethodsA retrospective cohort study was performed in a tertiary referral hospital. Patients ≥18 years old with suspected PAD who underwent ACCmax measurement(s) along with computed tomography angiography of the abdominal aorta and lower extremities (reference test) were eligible for inclusion. ACCmax measurements of the posterior tibial artery, anterior tibial artery and peroneal artery were collected. Diagnostic performance was assessed by using sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and area under the curve (AUC). ResultsIn total, 340 patients (618 limbs) were included. Approximately 40% suffered from DM and 30% had CKD. Diagnostic performance of the ACCmax to detect PAD for the posterior tibial artery showed a sensitivity of 90%, specificity of 93%, positive likelihood ratio of 12.83, and negative likelihood ratio of 0.11 (AUC, 0.953). For the anterior tibial artery, these results were 94%, 97%, 32.06, and 0.06 (same sequence as presented before) with an AUC of 0.984. The peroneal artery had a performance of 86%, 89%, 7.51, and 0.16, respectively (AUC, 0.893). Diagnostic accuracy of the ACCmax did not diminish in subgroup analysis for patients with DM or CKD. ConclusionsThe ACCmax showed excellent diagnostic performance to detect PAD, independent of patients prone to medial arterial calcification.

Screening for Peripheral Artery Disease Using an Automated Four-Limb Blood Pressure Monitor Equipped with Toe-Brachial Index Measurement.

Toe-brachial index (TBI) measurement helps to detect peripheral artery disease (PAD) in patients with incompressible ankle arteries due to medial arterial calcification, which is most frequently associated with diabetes. We aimed to evaluate how an automated four-limb blood pressure monitor equipped with TBI measurement could contribute to PAD screening. In 117 patients (mean age 63.2 ± 12.8 years), ankle-brachial index (ABI) measurement was performed using the Doppler-method and the MESI mTablet. TBI was obtained via photoplethysmography (MESI mTablet, SysToe) and a laser Doppler fluxmeter (PeriFlux 5000). Lower limb PAD lesions were evaluated based on vascular imaging. A significant correlation was found between Doppler and MESI ankle-brachial index values (r = 0.672), which was stronger in non-diabetic (r = 0.744) than in diabetic (r = 0.562) patients. At an ABI cut-off of 0.9, Doppler (AUC = 0.888) showed a sensitivity/specificity of 67.1%/97.4%, MESI (AUC 0.891) exhibited a sensitivity/specificity of 57.0%/100%; at a cut-off of 1.0, MESI demonstrated a sensitivity/specificity of 74.7%/94.8%. The TBI values measured using the three devices did not differ significantly (p = 0.33). At a TBI cut-off of 0.7, MESI (AUC = 0.909) revealed a sensitivity/specificity of 92.1%/67.5%. Combining MESI ABI and TBI measurements recognised 92.4% of PAD limbs. Using an ABI cut-off level of 1.0 and sequential TBI measurement increases the sensitivity of the device in detecting PAD. The precise interpretation of the obtained results requires some expertise.

Antihypertensive treatment with hydrochlorothiazide-hydralazine combination aggravates medial vascular calcification in CKD rats with mineral bone disorder.

Arterial stiffness and medial vascular calcification, leading to isolated systolic blood pressure (BP), are major cardiovascular risk factors in patients with chronic kidney disease (CKD) and mineral bone disorders (MBD). The impact of BP on MBD-induced medial vascular calcification in CKD remains uncertain. We investigated whether BP reduction improves arterial stiffness and medial vascular calcification in a rat model of CKD-MBD. CKD was induced in Wistar rats by subtotal nephrectomy. Then, MBD was generated by a Ca/P-rich diet with calcitriol supplementation to induce medial vascular calcification. Two antihypertensive treatments were evaluated: (1) the angiotensin AT1 receptor antagonist losartan, and (2) the combination of the thiazide diuretic hydrochlorothiazide and the direct vasodilator hydralazine (HCTZ/HY). After 5 weeks, mean BP (MBP), pulse pressure (PP), and pulse wave velocity (PWV) were determined. Vascular calcification was assessed in the thoracic aorta. While MBP was similar in CKD-MBD and control CKD rats, PP and PWV were increased in CKD-MBD rats. The heightened arterial stiffness in CKD-MBD rats was associated with diffused medial calcification along the thoracic aorta. Although both losartan and HCTZ/HY reduced MBP in CKD-MBD rats, losartan did not affect PP and PWV nor medial vascular calcification, whereas HCTZ/HY, unexpectedly, further increased arterial stiffness and medial vascular calcification. In the rat model of CKD-MBD, antihypertensive treatment with losartan did not affect arterial stiffness or medial vascular calcification. However, HCTZ/HY treatment aggravated arterial stiffness and vascular calcification despite a similar reduction of MBP, suggesting a blood pressure-independent mechanism for vascular calcification.

Pedal Medial Arterial Calcification Influences Outcomes of Isolated Inframalleolar Interventions

Pedal Medial Arterial Calcification Influences Outcomes of Isolated Inframalleolar Interventions

Ultrasound-detected tibial artery calcification as a marker of cardiovascular and lower-limb risk in asymptomatic patients with type-2 diabetes.

Medial arterial calcification (MAC) is a vascular disease distinct from atherosclerosis. Recently, several studies have demonstrated that MAC is an important marker of cardiovascular events. We aim to assess the presence of MAC during ultrasound screening of lower-limb vasculature and its association with both cardiovascular (CV) and lower-limb events in patients with type-2 diabetes. A retrospective cohort study was conducted on 1119 patients with type-2 diabetes free from CV disease. A CV work-up, including vascular ultrasound, was performed for each patient. The presence of MAC was assessed on posterior tibial arteries and ankle-brachial index (ABI) was measured. Major acute CV events (MACEs) and lower-limb events (MALEs) were recorded as a composite endpoint for a 5-year period. We identified MAC among 212 (18.9%) patients. The independent determinants of MAC were age and diabetic retinopathy. Over a period of 5 years, 125 MACEs and 22 MALEs occurred. MAC was significantly associated with the composite outcome MACE + MALE (HR = 1.94; 95% CI: 1.23, 3.08, p = 0.005) or with MACE (HR = 1.85; 95% CI: 1.16, 2.95, p = 0.010). Adjusted for ABI and diabetic foot wound, MAC remained a determinant of MALE (HR = 5.49; 95% CI: 2.19, 13.76, p < 0.001). Considering each ABI group, MAC was associated with both MACE and MALE in the normal ABI group. Ultrasound-detected MAC on tibial arteries seems to be a determinant of both CV and lower-limb events, independent from ABI. MAC helps to refine the CV risk in patients with normal ABI.

Medial arterial calcification score is associated with increased risk of major limb amputation

ObjectiveThe pedal medial arterial calcification (MAC) score has been associated with risk of major limb amputation in patients with chronic limb-threatening ischemia. This study aimed to validate the pedal MAC scoring system in a multi-institutional analysis to validate its usefulness in limb amputation risk prediction. MethodsA multi-institution, retrospective study of patients who underwent endovascular or open surgical infrainguinal revascularization for chronic limb-threatening ischemia was performed. MAC scores of 0 to 5 were assigned based on visible calcified arteries on foot X ray then trichotomized (0-1, 2-4, 5) for analysis. The primary outcome was major limb amputation at 6 months. Adjusted Kaplan-Meier models were used to analyze time-to-major amputation across groups. ResultsThere were 176 patients with 184 affected limbs (mean age, 66 years; 61% male; 60% White), of whom 97% presented with a wound. The MAC score was 0 in 41%, 1 in 9%, 2 in 13%, 3 in 11%, 4 in 13%, and 5 in 13% of the limbs. There were 26 major amputations (14%) and 16 deaths (8.7%) within 6 months. Patients with MAC 5 had a significantly higher risk of major limb amputation than both the 0 to 1 and 2 to 4 groups (P = .001 and P = .044, respectively), and lower overall amputation-free survival (log-rank P = .008). ConclusionsPedal MAC score is a reproducible and generalizable measure of inframalleolar arterial disease that can be used with Wound, Ischemia, and foot Infection staging to predict major limb amputation in patients with chronic limb-threatening ischemia.

Cold exposure protects against medial arterial calcification development via autophagy

Medial arterial calcification (MAC), a systemic vascular disease different from atherosclerosis, is associated with an increased incidence of cardiovascular events. Several studies have demonstrated that ambient temperature is one of the most important factors affecting cardiovascular events. However, there has been limited research on the effect of different ambient temperatures on MAC. In the present study, we showed that cold temperature exposure (CT) in mice slowed down the formation of vitamin D (VD)-induced vascular calcification compared with room temperature exposure (RT). To investigate the mechanism involved, we isolated plasma-derived exosomes from mice subjected to CT or RT for 30 days (CT-Exo or RT-Exo, respectively). Compared with RT-Exo, CT-Exo remarkably alleviated the calcification/senescence formation of vascular smooth muscle cells (VSMCs) and promoted autophagy by activating the phosphorylation of AMP-activated protein kinase (p-AMPK) and inhibiting phosphorylation of mammalian target of rapamycin (p-mTOR). At the same time, CT-Exo promoted autophagy in β-glycerophosphate (β-GP)-induced VSMCs. The number of autophagosomes and the expression of autophagy-related proteins ATG5 and LC3B increased, while the expression of p62 decreased. Based on a microRNA chip microarray assay and real-time polymerase chain reaction, miR-320a-3p was highly enriched in CT-Exo as well as thoracic aortic vessels in CT mice. miR-320a-3p downregulation in CT-Exo using AntagomiR-320a-3p inhibited autophagy and blunted its anti-calcification protective effect on VSMCs. Moreover, we identified that programmed cell death 4 (PDCD4) is a target of miR-320a-3p, and silencing PDCD4 increased autophagy and decreased calcification in VSMCs. Treatment with CT-Exo alleviated the formation of MAC in VD-treated mice, while these effects were partially reversed by GW4869. Furthermore, the anti-arterial calcification protective effects of CT-Exo were largely abolished by AntagomiR-320a-3p in VD-induced mice. In summary, we have highlighted that prolonged cold may be a good way to reduce the incidence of MAC. Specifically, miR-320a-3p from CT-Exo could protect against the initiation and progression of MAC via the AMPK/mTOR autophagy pathway.Graphic

Extracellular vesicles in atherosclerosis and vascular calcification: the versatile non-coding RNAs from endothelial cells and vascular smooth muscle cells.

Atherosclerosis (AS) is characterized by the accumulation of lipids, fibrous elements, and calcification in the innermost layers of arteries. Vascular calcification (VC), the deposition of calcium and phosphate within the arterial wall, is an important characteristic of AS natural history. However, medial arterial calcification (MAC) differs from intimal calcification and cannot simply be explained as the consequence of AS. Endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) are directly involved in AS and VC processes. Understanding the communication between ECs and VSMCs is critical in revealing mechanisms underlying AS and VC. Extracellular vesicles (EVs) are found as intercellular messengers in kinds of physiological processes and pathological progression. Non-coding RNAs (ncRNAs) encapsulated in EVs are involved in AS and VC, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). The effects of ncRNAs have not been comprehensively understood, especially encapsulated in EVs. Some ncRNAs have demonstrated significant roles in AS and VC, but it remains unclear the functions of the majority ncRNAs detected in EVs. In this review, we summarize ncRNAs encapsulated in EC-EVs and VSMC-EVs, and the signaling pathways that are involved in AS and VC.

Treatment effect of medial arterial calcification in below-knee after Auryon laser atherectomy using micro-CT and histologic evaluation

PurposeTo determine the frequency of medial arterial calcification (MAC) fracture following Auryon laser atherectomy using micro-CT and histologic evaluation in an atherosclerotic human cadaveric limb model. MethodsTwo below-the-knee calcified arterial segments from human cadaver limbs underwent treatment with the Auryon laser system with or without plain old balloon angioplasty (POBA). Micro-CT and angiography were performed before and after treatment followed by histological evaluation of regions showing calcium disruption. ResultsAll treatment zones were successfully treated with the Auryon laser (n = 9). Six of 9 treatment zones showed calcium fracture on micro-CT. Each treatment zone was further subdivided using micro-CT analysis (36 evaluated sections) of which 18 sections revealed calcium fracture. Sections with calcium fracture had significantly more confluent and uninterrupted circumferential calcification than sections without calcium fracture (arc of calcification 360.0 [323.7–360.0] vs 312.8 [247.4–314.2] degree, p = 0.007), whereas there were no differences in size of calcium burden (3.4 [2.8–3.9] vs 2.8 [1.3–4.6] mm2, p = 0.46). No arterial dissection or rupture was seen. ConclusionsAuryon laser atherectomy produced fractures of medial arterial calcification in this cadaveric human atherosclerotic peripheral artery model. This effect was observed in arterial segments with a pattern of circumferential uninterrupted calcification (i.e. larger arc of calcification) regardless of calcium burden. Our pilot data suggests Auryon laser may be a promising therapy for calcified lesions.

AMBULATORY BLOOD PRESSURE MONITORING IN PATIENTS WITH MEDIAL ARTERIAL CALCIFICATION

Objective: Several studies have shown that reduced ankle-brachial pressure index (ABI) is a reliable warning sign of increased cardiovascular risk. But also ABI values above 1.3 in the presence of medial arterial calcification (MAC) are associated with increased mortality due to cardiovascular causes. Aim of the study was in a group of patients with MAC using ambulatory blood pressure monitoring (ABPM) to document frequent occurence of arterial hypertension, with also frequent diurnal pattern loss, as significant factors in patients prognosis. Design and method: We examined 41 patients (25 men, 16 women) with identified MAC. Mean age 59 years (50-79 years). All patients have been treated for diabetes mellitus, type 2, most of them, 23 (56.1 %) with insulin. The mean duration of diabetes was 12.6 years. MAC was detected by the BOSO, ABI system 100 (Germany), using the oscillometric method of measuring blood pressure. ABI value was calculated as the ratio of the value of higher pressure in the leg to a higher pressure on the upper extremities. ABPM was performed with the Cardiosoft-Tonoport V, General Electric (USA). Results: 35 patients (85,4 %) had arterial hypertension, most of them, 20 (48,8 %) grade 3 hypertension (according to ESC/ESH Guidelines). 14 patients (40 %) had a preserved diurnal rhythm (dipping), 18 (51.4 %) had it disturbed (non-dippers or risers). In 3 patients (8.6 %) we did not determine the diurnal sign for night vigil. Conclusions: In patients with MAC, we found a high prevalence of arterial hypertension, and a diurnal rhythm disorder was also very frequent. This fact may also contribute to the worsened cardiovascular prognosis of these patients. Therefore ABPM in patients with MAC is highly recommended, since subsequent cardiology management can improve their prognosis.

Medial Arterial Calcification Score is Associated Eith Risk of Major Limb Amputation

The medial arterial calcification (MAC) score has been associated with risk of major limb amputation in patients with chronic limb-threatening ischemia (CLTI) in a single-center study, but has not been validated. The objective of this study was to apply MAC scores to diverse, geographically distributed patients to confirm its usefulness in inframalleolar artery assessment and limb amputation risk prediction. We performed a multi-institution, retrospective study of 176 patients who underwent infrainguinal revascularization for CLTI between January 1, 2015, and July 1, 2020. Patients who did not have a two-view foot x-ray at the time of their revascularization were excluded. MAC scores of 0 to 5 were assigned based on the degree of visible calcium on foot x-ray using the previously described scoring method. A trichotomized MAC score (0-1, 2-4, and 5) was used for analysis. The primary outcome was major limb amputation at 6 months. Adjusted Kaplan-Meier models were used to analyze time-to-major amputation across MAC score groups. Kaplan-Meier survival curves were compared using the log-rank test. Deaths during the study period and those who did not undergo a major amputation within 6 months of their foot x-ray were censored. The final adjustment set included diabetes, chronic kidney disease (CKD) 3b-5, end-stage renal disease (ESRD), and Society for Vascular Surgery Wound, Ischemia, foot Infection wound grade. Clustering was addressed at the patient level. The final cohort included 176 patients with 184 affected limbs (mean of 66.4 ± 11.5 years old, 60.7% male, 60.0% White), of whom 96.7% presented with a wound. The cohort included 23.4% with ESRD, 15.22% with CKD 3b-5, and 77.0% with diabetes mellitus. The MAC score was 0 in 40.8%, 1 in 9.2%, 2 in 13.0%, 3 in 11.4%, 4 in 12.5%, and 5 in 13.0% of the limbs. There were 26 major amputations (14.1%) and 16 deaths (8.7%). Patients with MAC 5 had a significantly higher risk of major limb amputation (log-rank P-value = .008) (Fig 1). MAC scoring is a reproducible and generalizable measurement of inframalleolar arterial disease that can be used as an adjunct to the Society for Vascular Surgery Wound, Ischemia, foot Infection staging system as a predictor of major limb amputation in patients with CLTI.

A nonobstructive condition: Medial arterial calcification.

Vascular calcification, including intimal and medial calcification, is closely associated with a significant increase in cardiovascular diseases. Although increased understandings were achieved, people still know much more about intimal calcification than medial calcification because the latter doesn't obstruct the arterial lumen, commonly considered as a non-significant finding. We clarified the pathologic characteristic of medial calcification, its difference from intimal calcification, principally focused on its clinical relevance, such as diagnosis, nosogenesis, and hemodynamics. We underline the importance of identifying and distinguishing medial calcification, understanding its effect to local/systematic arterial compliance, and relationship to diabetic neuropathy. Recent studies emphasize do not ignore its predictive role in cardiovascular mortality. It is of great clinical significance to summarize the mechanisms of occurrence, lesion characteristics, diagnostic methods, pathogenic mechanisms, hemodynamic changes, and the distinction as well as association of intimal calcification with intimal calcification.

351 Trends Between Periodontitis and Medial Arterial Calcification in Undiagnosed Type II Diabetes Mellitus

OBJECTIVES/GOALS: The overall objective of this study is to determine if medial arterial calcification (MAC) is an independent predictor of diabetes and to evaluate the relationship between MAC, periodontitis and Type II diabetes mellitus. METHODS/STUDY POPULATION: A retrospective case-control model analyzing radiographs for periodontitis and MAC to identify potential biomarkers for underlying systemic conditions, such as diabetes. Charts of patients attending UPENN School of Dental Medicine clinics between 2015 and 2022 were reviewed. Demographics, medical and dental history, diabetic status (identified by POC blood glucose level, fasting blood glucose and/or A1C), and medication history were documented amongst other variables. Patients aged 18 years or older with diabetes and having full mouth intraoral radiographs (FMX), panoramic radiographs and CBCTs were included. Patients with radiographs of poor quality were excluded. Multivariate analysis was used to determine possible associations between diabetes and periodontitis among persons with or without MAC. RESULTS/ANTICIPATED RESULTS: In our pilot study involving 28 participants, 53% of the population with moderate or severe periodontitis had MAC. By the Fisher’s Exact Test, there was an association, meaning those with more periodontal disease are more likely to have MAC (p=0.014). Sixty-three percent of patients with diabetes had MAC, while 19% of patients without evidence of diabetes also had MAC, (p=0.067). There was not enough evidence of association between diabetes and presence of MAC at this time, due to a small sample size, however there was a high prevalence of MAC among the diabetics. We hypothesized that periodontitis, a condition that shares many risk factors with diabetes would also be associated with incident MAC. Findings from this study will be key for the implementation of preventive screening protocols and referral systems. DISCUSSION/SIGNIFICANCE: Diabetes is on the rise and about half of diabetics are undiagnosed. CBCT imaging frequently used in dentistry can detect incidental findings such as MAC. This study has the potential of detecting statistically significant links between MAC, periodontitis and diabetes, hence serving as a sensitive radiographic biomarker for diabetes.

Learning Genotyping and Cell Culture Techniques to Perform Experiments to Study Cardiovascular Calcification

The St. Hilaire Lab at the University of Pittsburgh studies important cardiovascular diseases such as Calcific Aortic Valve Disease (CAVD), Arterial Calcification due to Deficiency of CD73 (ACDC) and Medial Arterial Calcification (MAC). The similarity between all these conditions is the calcification of cells, which leads to the main research question of the lab: how and why does a healthy cell transition into an osteogenic cell? To determine why a healthy cell becomes calcified, we perform experiments using both in vivo and in vitro environments. However, to begin in vitro experiments that involve valuable human cells, basic techniques in cell culture such as plating and splitting are needed, and in vivo experiments require knowing the genotype of the animals being used. With these fundamental techniques, biochemical analysis such as qPCR, western blots and staining can be performed in order to help answer research questions that pertain to the lab.

Lower-limb peripheral arterial disease and amputations in people with diabetes: Risk factors, prognostic value and management

Lower-limb peripheral arterial disease (PAD), is a common manifestation of systemic atherosclerosis, resulting from a partial or complete obstruction of at least one lower-limb arteries. PAD is a major endemic disease with an excess risk of major cardiovascular events and death. It also leads to disability, high rates of lower-limb adverse events and non-traumatic amputation. In patients with diabetes, PAD is particularly frequent and has a worse prognosis than in patients without diabetes. The risk factors of PAD are comparable to those for cardiovascular disease. The ankle-brachial index is usually recommended to screen PAD despite its limited performance in patients with diabetes, affected by the presence of peripheral neuropathy, medial arterial calcification, incompressible arteries and infection. Toe brachial index and toe pressure emerge as alternative screening tools. The management of PAD requires strict control of cardiovascular risk factors including diabetes, hypertension and dyslipidaemia, the use of antiplatelet agents and lifestyle management, to reduce cardiovascular adverse events, but few randomized controlled trials have evaluated the benefits of these treatments in PAD. Several advances have been achieved in endovascular and surgical revascularization procedures, with obvious improvement in PAD prognosis. Further studies are required to increase our understanding of the pathophysiology of PAD and to evaluate the interest of different therapeutic strategies in the occurrence and progression of PAD in patients with diabetes. Here, we present a narrative and contemporary review to synthesize the key epidemiology findings, screening and diagnosis methods, and major therapeutic advances regarding PAD in patients with diabetes.