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Background Early government‐mandated restrictions in Australia and New Zealand contributed to a successful public health outcome during the COVID‐19 pandemic, including an unprecedented temporary cancellation of all non‐urgent elective surgical procedures. This study describes the change in vascular surgery services across Australia and New Zealand before and during the COVID‐19 restrictions. Methods De‐identified data from the Australia and New Zealand Society for Vascular Surgery Australasian Vascular Audit from January 2015 to September 2020 was obtained. Vascular surgery procedure numbers from January to September of 2020 (study period) was compared to the corresponding months between 2015 and 2019 (pre‐study period). The volume of procedures, both elective and emergency, were compared. Subgroup analyses included procedures categorized by operation type and location. Results There was a 11% decrease in total vascular procedures, 22% decrease in elective procedures, and a 14% increase in emergency procedures, comparing the study and pre‐study periods. There was a large increase in all revascularization procedures for critical limb ischemia and no change in acute limb ischemia interventions, without a concomitant rise in major or minor all‐cause amputation. There was a decrease in interventions for abdominal aortic aneurysm and carotid artery disease, driven by a fall in elective procedures, while volume for dialysis access remained the same. Change in procedural volume varied by state with the largest decrease noted in NSW and Victoria. Conclusions The COVID‐19 pandemic reduced vascular surgery procedures across Australia and New Zealand with a decrease in elective operations and an increase in emergency operations., Total, elective, and emergency procedure numbers per month. Box and whisker plots represent monthly procedure numbers between 2015‐2019. The red dot represents monthly procedure numbers in 2020. Whiskers represent monthly minimum and maximum numbers (outliers included), while the box represents median with 1st and 3rd quartiles.

Aim To assess the current evidence, controversies and technologies behind the various approaches and steps in the management of Paget-Schroetter syndrome. Materials and methods We performed a narrative review based on a literature search in Embase, Medline, Pubmed and Google Scholar through keyword searching related to upper extremity deep vein thrombosis, Paget-Schroetter syndrome and venous thoracic outlet syndrome. Results There is a paucity of high-quality evidence assessing the efficacy of contemporary approaches for the management of acute upper extremity deep vein thrombosis which, though promising, is largely limited to single institution case studies and small series. As a result, a formal systematic review could not be performed. Conclusions Paget-Schroetter syndrome is a rare condition, whose management approaches are largely guided by the accumulated expertise and clinical experience of vascular specialists. In the absence of randomized controlled trials, current practice has been guided by retrospective reviews and experience. Modern approaches and protocols appear to remain distinct between health care facilities, but have common features including early clot lysis, surgical decompression with first rib resection, followed by adjunctive open or endovascular procedures. Further high-quality level 1 evidence and research are required in order to standardize treatment for this condition.

Background Axillary lymph node dissection (ALND) can be avoided in breast cancer patients with low-volume disease in the sentinel lymph nodes (SLNs) according to Z0011 trial. We believe that nomograms developed for predicting non-sentinel lymph node (NSLN) metastases can guide the axillary treatment in patients who do not fully match the criteria of Z0011 study. We identified risk factors and evaluated the performance of three nomograms to predict NSLN status in patients with positive SLNs. Methods Data from 526 breast cancer patients with positive SLNs who underwent ALND at two Australian hospitals from 2002 to 2015 were studied. Univariate and multivariate associations for NSLN metastasis were analysed. Predictive models evaluated were MD Anderson Cancer Centre (MDA), Helsinki University Hospital and Memorial Sloan Kettering Cancer Centre. Results Thirty-nine per cent of patients demonstrated NSLN metastasis. The multivariate analysis identified extranodal extension (OR 3.2, 95% CI 2.07-4.80), tumour size >2 cm (OR 2.5, 95% CI 1.66-3.89), macrometastasis (OR 1.9, 95% CI 1.09-3.47), positive SLN ratio >0.5 (OR 1.7, 95% CI 1.16-2.60) and lymphovascular invasion (OR 1.6, 95% CI 1.09-2.44) as independent predictors for NSLN metastasis. MDA nomogram showed the best discrimination (area under the curve of 0.74) and a 9% false negative rate for predicted probability of NSLN metastasis ≤10%. Conclusion Our results suggest that presence of extranodal extension and tumour size >2 cm may influence the need of further axillary treatment. Conversely, ALND can be safety spared in low risk patients identified by MDA nomogram.

Carotid-femoral pulse wave velocity is associated with arterial stiffness in major elastic arteries, and predicts future cardiovascular events. However, little is known about carotid-femoral pulse wave velocity as a marker of vascular health in children. Semi-automated cuff-based devices for assessing pulse wave velocity are increasingly popular, although these utilize an algorithm developed and validated in adults. Physiological differences between adults and children may, however, reduce the accuracy of cuff-based methods. We sought to determine the accuracy of a cuff-based pulse wave velocity device in healthy children, and determine whether a novel age-appropriate algorithm increases accuracy. We recruited 29 healthy children between the ages of 2 and 20 years. Pulse wave velocity was measured both by using a tonometer on the carotid artery and an inflated cuff on the thigh, and using a tonometer on both the carotid artery and femoral artery as a reference standard. Accuracy of the cuff-based device with its standard algorithm developed in adults, and a novel age-appropriate algorithm corrected for physiological differences in leg pulse wave velocity was assessed with Regression analysis and Bland-Altman plots. Cuff-based device estimates of pulse wave velocity had excellent agreement to the reference standard (Δ = -0.26 ms-1 [SD 0.44]). The novel age-appropriate algorithm improved the accuracy of the cuff-based method (Δ = 0.02 ms-1 [SD 0.44]). The cuff-based semi-automatic approach estimates carotid-femoral pulse wave velocity with excellent agreement to the reference standard. However, adjusting the algorithm for known differences in leg pulse wave velocity further improves the accuracy of cuff-based measurement in children and adolescents.

Central Systolic Blood Pressure (cSBP) and Central Augmentation Index (cAIx) have been independently associated with cardiovascular risk in adults, and can be estimated using a generalized peripheral-to-central transfer function. We hypothesize that transfer function accuracy and precision will be influenced by degree of growth and change in body habitus during periods of growth, such as in childhood. We studied the pulse pressure waveforms of 91 healthy children at 8-years of age, and subsequently at 14-years of age. Waveforms were obtained by high-fidelity applanation tonometry of the radial and carotid arteries. Individualized radial-to-carotid transfer functions were formulated at 8-years of age and applied at 14-years of age to estimate cSBP and cAIx. Accuracy was defined as the difference between directly measured and predicted values, and precision as the residuals. Changes in weight (vs. error: β = −0.22, p = 0.04; vs. residuals: β = 0.30; p < 0.01) and body mass index (vs. residuals: β = 0.28, p < 0.01), between 8 and 14 years of age were associated with accuracy and precision of individualized transfer functions in predicting cSBP at 14 years of age. Change in weight (vs. residuals: β = 0.30; p < 0.01) and heart rate (vs. residuals β = 0.32, p < 0.01) were associated with the precision in predicting cAIx. Changes in body habitus and heart rate over a 6-year period of growth are associated with the predictive accuracy and precision of individualized transfer functions in children suggestive of changes in the frequency response characteristics of an individual’s vascular system during growth periods.

Background In adults, central systolic blood pressure (cSBP) and augmentation index (cAIx) are independently associated with cardiovascular events and mortality. There is increasing interest in central hemodynamic indices in children. We aimed to assess the accuracy of current techniques against invasive intra-aortic measurements in children. Methods Intra-aortic pressure waveforms were recorded with simultaneous brachial, radial, and carotid waveforms in 29 children (6.7 ± 3.9 years old) undergoing cardiac catheterization. Adult and age-appropriate transfer functions (TFs) (brachial adult: b-aTF; radial adult: r-aTF; radial for 8-year-old children: TF8; and radial for 14-year-old children: TF14) were used to synthesize central aortic waveforms from peripheral waveforms calibrated either to invasively or noninvasively recorded BP. Central hemodynamic indices were measured by pulse wave analysis. Results cSBP measured from invasively calibrated r-aTF (β = 0.84; intraclass correlation coefficient = 0.91; mean error ± SDD = −1.0 ± 5.0 mm Hg), TF8 (β = 0.78; intraclass correlation coefficient = 0.84; mean error ± SDD = 4.4 ± 5.6 mm Hg), and TF14 (β = 0.82; intraclass correlation coefficient = 0.90; mean error ± SDD = 2.0 ± 4.7 mm Hg)-synthesized central waveforms correlated with and accurately estimated intra-aortic cSBP measurements, while noninvasively calibrated waveforms did not. cAIx derived from TF-synthesized central waveforms did not correlate with intra-aortic cAIx values, and degree of error was TF-dependent. Conclusions The currently available r-aTF accurately estimates cSBP with invasive pulse pressure calibration, while age-appropriate TFs do not appear to provide additional benefit. Accuracy of cAIx estimation appears to be TF dependent.

Background: Arterial stiffness is a significant cardiovascular risk factor. Carotid-femoral pulse wave velocity (cfPWV) is the standard for measuring arterial stiffness, but indices such as central augmentation index (cAIx) and carotid artery elasticity (cE[p]) also correlate to arterial stiffness. Early-life determinants of arterial stiffening are not well understood. We assessed the relationship between population-indexed anthropometric and hemodynamic parameters, and arterial stiffness in healthy children. Methods: 97 healthy children between 2 to 20 years old were recruited. Z-scores for height, BMI, and brachial systolic (bSBP) and diastolic (bDBP) blood pressure were calculated [1,2]. cfPWV and central arterial waveforms were measured using the Sphygmocor XCEL and CvMS devices (AtCor, Sydney) respectively. Carotid artery maximum and minimum diameters were measured by high-resolution ultrasonography. cfPWV, cE[p], and cAIx were calculated. Results: In bivariate analysis, cfPWV was associated with age (b = 0.52, p < 0.01) and bSBP z-score (b = 0.24, p = 0.03). These associations were independent of sex, height z-score, BMI z-score, and bDBP z-score in a multivariable model (R2 = 0.23). cE[p] was significantly associated with age (b = 0.42, p < 0.01), bSBP z-score (b = 0.45, p < 0.01), and height z-score (b = −0.33, p = 0.01), but only bSBP z-score remained statistically significant in the multivariable model (b = 0.45, p < 0.01; R2 = 0.20). cAIx was not associated with anthropometric or hemodynamic z-scores. Conclusion: cfPWV is associated with age and bSBP z-score, while cE[p] is associated with bSBP z-score only, suggesting a potentially key association between systolic blood pressure and indices of arterial stiffness independent of age and other parameters of growth during healthy early life.

Central blood pressure can be estimated from peripheral pulses in adults using generalised transfer functions (TF). We sought to create and test age-specific non-invasively developed TFs in children, with comparison to a pre-existing adult TF. We studied healthy children from two sites at two time points, 8 and 14 years of age, split by site into development and validation groups. Radial and carotid pressure waveforms were obtained by applanation tonometry. Central systolic pressure was derived from carotid waveforms calibrated to brachial mean and diastolic pressures. Age-specific TFs created in the development groups (n=50) were tested in the validation groups aged 8 (n=137) and 14 years (n=85). At 8 years of age, the age-specific TF estimated 82, 99 and 100% of central systolic pressure values within 5, 10 and 15 mm Hg of their measured values, respectively. This TF overestimated central systolic pressure by 2.2 (s.d. 3.7) mm Hg, compared to being underestimated by 5.6 (s.d. 3.9) mm Hg with the adult TF. At 14 years of age, the age-specific TF estimated 60, 87 and 95% of values within 5, 10 and 15 mm Hg of their measured values, respectively. This TF underestimated central systolic pressure by 0.5 (s.d. 6.7) mm Hg, while the adult TF underestimated it by 6.8 (s.d. 6.0) mm Hg. In conclusion, age-specific TFs more accurately predict central systolic pressure measured at the carotid artery in children than an existing adult TF.

SummaryObjective Obesity is an established risk factor for cardiovascular disease. The mechanisms by which obesity affects cardiovascular risk have not been fully elucidated. This paper reports a comprehensive systematic review and meta-analysis on obesity and two key aspects of vascular health using gold-standard non-invasive measures – arterial endothelial function (brachial flow-mediated dilatation) and subclinical atherosclerosis (carotid intima-media thickness). Methods Electronic searches for ‘Obesity and flow-mediated dilatation’ and ‘Obesity and intima-media thickness’ were performed using Ovid Medline and Embase databases. A meta-analysis was undertaken for brachial flow-mediated dilatation and carotid intima-media thickness to obtain pooled estimates for adults with obesity and those with healthy weight. Results Of the 5,810 articles retrieved, 19 studies on flow-mediated dilatation and 19 studies on intima-media thickness were included. Meta-analysis demonstrated that obesity was associated with lower flow-mediated dilatation (−1.92 % [95% CI −2.92, −0.92], P = 0.0002) and greater carotid intima-media thickness (0.07 mm [95% CI 0.05, 0.08], P

Carotid-femoral pulse wave velocity is associated with arterial stiffness in major elastic arteries, and predicts future cardiovascular events. However, little is known about carotid-femoral pulse wave velocity as a marker of vascular health in children. Semi-automated cuff-based devices for assessing pulse wave velocity are increasingly popular, although these utilize an algorithm developed and validated in adults. Physiological differences between adults and children may, however, reduce the accuracy of cuff-based methods. We sought to determine the accuracy of a cuff-based pulse wave velocity device in healthy children, and determine whether a novel age-appropriate algorithm increases accuracy. We recruited 29 healthy children between the ages of 2 and 20 years. Pulse wave velocity was measured both by using a tonometer on the carotid artery and an inflated cuff on the thigh, and using a tonometer on both the carotid artery and femoral artery as a reference standard. Accuracy of the cuff-based device with its standard algorithm developed in adults, and a novel age-appropriate algorithm corrected for physiological differences in leg pulse wave velocity was assessed with Regression analysis and Bland-Altman plots. Cuff-based device estimates of pulse wave velocity had excellent agreement to the reference standard (Δ = -0.26 ms

Background: Carotid femoral pulse wave velocity (cfPWV) is directly associated with arterial stiffness in major elastic arteries and predicts future cardiovascular events (1). Little is known of cfPWV as a marker of vascular health in children. Semi-automated cuff-based devices for assessing cfPWV are increasingly popular, although these utilize an algorithm developed and validated in adults (2). Physiological differences between adults and children may thus reduce the accuracy of cuff-based. Methods: We sought to determine the accuracy of a cuff-based cfPWV device in healthy children and determine whether an age-appropriate algorithm increases accuracy. Methods we prospectively recruited 29 healthy children (mean age = 11.5 ± 5.2 years old). cfPWV was measured using a tonometer on the carotid artery and an inflated cuff on the thigh (Sphygmocor XCEL; AtCor Medical, Australia), and using a tonometer on both the carotid artery and femoral artery (SphygmoCor CvMS; AtCor Medical, Australia) as a reference method. We assessed the accuracy of the cuff-based device with its standard algorithm that was developed in adults, and an adjusted algorithm corrected for physiological differences in leg (femoral to thigh cuff) PWV between adult and children (3). Results: Cuff-based device estimates of cfPWV in children had excellent agreement to the reference standard (r = 0.85; Δ = −0.26 ms−1 [SD 0.44]). The adjusted algorithm improved the accuracy of the cuff-based method (r = 0.84; Δ=0.02 ms−1 [SD 0.44]) (Figure 1). Conclusions: Although the cuff-based semi-automatic approach estimates cfPWV with excellent agreement to the reference standard, adjusting the algorithm for known differences in leg PWV improves the accuracy of cuff-based measurement in children.

Objectives: Carotid-femoral pulse wave velocity (cfPWV) is a validated non-invasive measure of aortic stiffness. Risk factors for cfPWV are well described in adulthood, and furthermore cfPWV is associated with incident cardiovascular disease in adults (1). However, risk factors for arterial stiffness in childhood are poorly described (2). Accordingly, we sought to determine the risk factors for cfPWV in childhood and adolescence and hypothesized that cfPWV would be higher amongst those with greater adiposity. Methods: We prospectively recruited 88 healthy children (mean age = 11.0 ± 5.3 years old). Age, weight, height, and blood pressure were measured. cfPWV was assessed using a semi-automated cuff-based device (Sphygmocor XCEL; AtCor Medical, Australia), and body composition using air displacement plethysmography (BOD POD; Cosmed, Italy) (3). Associations with cfPWV were determined by multivariable linear regression, with subsequent mediation analyses to inform likely causal pathways. Results: After adjusting for age and sex, cfPWV was significantly associated with weight, body mass index (BMI), systolic blood pressure, mean blood pressure, heart rate, and lean body mass (LBM), while LBM was significantly associated with height, weight, BMI and fat mass (Table 1). After further adjusting for weight, mean blood pressure and heart rate, LBM remained significantly associated with cfPWV (ß = 0.68; p = 0.007). Mediation analyses indicate that weight mediates the association between age and cfPWV (PM = 76%), and that LBM mediates the relationship between weight and cfPWV (Figure 1). Conclusion: Higher cfPWV in healthy children and adolescents is a function of growth, and this association may be in turn mediated by higher LBM rather than adiposity.

Experimental evidence suggests that structural changes to the arterial adventitia may be a key vascular determinant of early arterial stiffening, although this has not been directly studied. Accordingly, we hypothesized that in young children, in whom this relationship would not be altered by atheroma, carotid extramedial thickness (EMT), a measure that incorporates the thickness of the arterial adventitia, perivascular tissues and the internal jugular venous wall, would be associated with localized arterial stiffness of the same arterial region.We studied 248 healthy prepubescent children (aged 8 years). Carotid diameter and carotid EMT were measured by high-resolution ultrasound. Carotid blood pressure was derived from brachial blood pressure and carotid tonometry. Three measures of localized arterial stiffness (β stiffness index, distensibility coefficient and incremental modulus of elasticity) were calculated for the common carotid artery. Results were adjusted for heart rate and DBP, two important hemodynamic determinants of arterial stiffness.Carotid EMT was associated with all three measures of arterial stiffness (β stiffness index: standardized β = 0.121, P = 0.03; distensibility coefficient: standardized β = -0.121, P = 0.05; incremental modulus of elasticity: standardized β = 0.140, P = 0.02). These associations remained significant after adjustment for potential confounders such as sex, height, waist circumference, BMI and body surface area.Carotid EMT is associated with the stiffness of the same arterial segment in children, suggesting that the arterial adventitia may be involved in early changes in arterial stiffness during childhood.

Objectives: Non-invasive methodologies for assessing arteriosclerosis, including carotid intimal-medial thickness (cIMT) for assessing subclinical atherosclerosis and carotid-femoral pulse wave velocity (cfPWV) for measuring arterial stiffness, are well established and validated in adults [1, 2]. However, they are less well-described in children. Alternative methodologies, such as aortic IMT (aIMT), may be more appropriate in children provided the natural history of atherosclerotic disease [3]. Previous studies have predominantly applied these methodologies in a narrow age-range of children; methodological differences between studies make inter-study comparison of absolute values difficult. Therefore, we aimed to assess the severity of arteriosclerosis across childhood and adolescence using standardised application of age-appropriate and established methodologies. Methods: We prospectively recruited 97 healthy children aged 2 to 20 (mean age = 11.2 ± 5.12 years old; stratified into five sex-balanced age groups). cIMT and aIMT were assessed via high-resolution B-mode ultrasonography. cfPWV was assessed via a semi-automated cuff-based device (Sphygmocor XCEL; AtCor Medical, Australia). Results: aIMT increased with age (9 μm per year [95% CI: 6, 12], p < 0.0001), whereas cIMT did not meaningfully increase with age (2 μm per year [95% CI: −1, 5], p = 0.14). cfPWV remained relatively stable during early childhood, with an apparent increase from adolescence onwards. Conclusions: Carotid and aortic atherosclerosis both increase throughout childhood, although this increase is greatest in the aorta. The aorta begins to stiffen during adolescence. Assessment of aortic arteriosclerosis is feasible in childhood and adolescence, and should be prioritised over assessment of carotid atherosclerosis in this age group.

Background: Central aortic pressure waveforms can be modelled non-invasively in adults using general transfer functions. These techniques have been applied to, but not formally validated in paediatric populations. We recently developed and validated two age-appropriate paediatric transfer functions and sought to determine their effectiveness in children and adolescents. Methods: We recruited 97 healthy children between 2 and 20 years of age in five pre-specified age groups. Central waveforms were estimated by applying two previously developed paediatric transfer functions developed in 8 year and 14 year-old children (8TF, 14TF respectively), and a proprietary adult transfer function (aTF) (Sphygmocor CvMS, AtCor) to radial waveforms measured by tonometry [1]. Estimated central arterial parameters were measured from direct carotid tonometry. Results: 8TF estimates higher cSBP than 14TF, which estimates higher cSBP than aTF across all ages. In contrast, 8TF estimates lower cAIx than 14TF, which estimates lower cAIx than aTF across all ages (Figure 1). 8TF most accurately modelled central arterial waveform features, specifically by cAIx when comparing to carotid tonometry, in early childhood (age groups: 2–6.5 years, 0 ± 14%; 6.6–9.5 years, − 4 ± 19%; 9.6–12.5 years, −6 ± 13%), while 14TF most accurately estimated cAIx in later childhood and adolescence (12.6–15.5 years, −3 ± 11%; 15.6–20 years, 4 ± 13%). Figure 1 Conclusion: Effectiveness of transfer functions for modelling central arterial waveforms in childhood appear to be age-dependent, with evidence of better accuracy when used in populations similar to that in which they were developed. These results support the use of multiple age-appropriate paediatric transfer functions over a generalized paediatric transfer function.

A 45-year-old woman was presented with a 2-year history of left lower limb claudication symptoms occurring only during long-distance running. Multimodal imaging with exercise duplex ultrasonography and magnetic resonance angiogram confirmed the presence of flow-limiting stenoses in the left external iliac artery consistent with a diagnosis of left external iliac artery endofibrosis. She successfully underwent a left external iliac endarterectomy with vein patch repair and returned to full physical activity soon after. A year following full recovery from her original operation, she presented with similar symptoms on the right side and was managed in a similar manner. This report illustrates an unusual case of bilateral iliac artery endofibrosis occurring in an older endurance runner. We also present a novel diagnostic modality of pre-exercise and postexercise magnetic resonance angiography for iliac endofibrosis.

The arterial adventitia has been implicated in the vascularremodelling process of atherosclerosis. Carotid extra-medialthickness (EMT) is a reproducible non-invasive measure ofelastic artery adventitial thickness obtained by high-resolutionultrasound [1,2]. Carotid EMT is correlated with both intima-media thickness (IMT) and arterial stiffness from the samearterial segment, yet is associated with cardiovascular risk fac-tors including BMI and diabetes independent of atheroscleroticinvolvement of the arterial intima and media [1,3–5].The prognostic significance of carotid EMT, however, hasnot yet been examined. Thus, we sought to determine whethercarotid EMT is associated with risk of incident cardiovascularevents, in adults at risk of coronary artery disease (CAD).

Observational studies and nonrandomized trials support an association between periodontal disease and atherosclerotic vascular disease. Both diseases occur frequently in Aboriginal Australians. We hypothesized that nonsurgical periodontal therapy would improve measures of arterial function and structure that are subclinical indicators of atherosclerotic vascular disease. This parallel-group, randomized, open label clinical trial enrolled 273 Aboriginal Australians aged ≥18 years with periodontitis. Intervention participants received full-mouth periodontal scaling during a single visit, whereas controls received no treatment. Prespecified primary end points measured 12-month change in carotid intima-media thickness, an indicator of arterial structure, and 3- and 12-month change in pulse wave velocity, an indicator of arterial function. ANCOVA used complete case data to evaluate treatment group differences. End points could be calculated for 169 participants with follow-up data at 3 months and 168 participants at 12 months. Intima-media thickness decreased significantly after 12 months in the intervention group (mean reduction=−0.023 [95% confidence interval {CI}, −0.038 to −0.008] mm) but not in the control group (mean increase=0.002 [95% CI, −0.017 to 0.022] mm). The difference in intima-media thickness change between treatment groups was statistically significant (−0.026 [95% CI, −0.048 to −0.003] mm; P =0.03). In contrast, there were no significant differences between treatment groups in pulse wave velocity at 3 months (mean difference, 0.06 [95% CI, −0.17 to 0.29] m/s; P =0.594) or 12 months (mean difference, 0.21 [95% CI, −0.01 to 0.43] m/s; P =0.062). Periodontal therapy reduced subclinical arterial thickness but not function in Aboriginal Australians with periodontal disease, suggesting periodontal disease and atherosclerosis are significantly associated.