Disease Beyond the Arch: A Systematic Review of Middle Aortic Syndrome in Childhood

BACKGROUND

Middle aortic syndrome (MAS) is a rare clinical entity in childhood, characterized by a severe narrowing of the distal thoracic and/or abdominal aorta, and associated with significant morbidity and mortality. MAS remains a relatively poorly defined disease. This paper systematically reviews the current knowledge on MAS with respect to etiology, clinical impact, and therapeutic options.

METHODS

A systematic search of 3 databases (Embase, MEDLINE, and Cochrane Central Register of Controlled Trials) yielded 1,252 abstracts that were screened based on eligibility criteria resulting in 184 full-text articles with 630 reported cases of childhood MAS. Data extracted included patient characteristics, clinical presentation, vascular phenotype, management, and outcomes.

RESULTS

Most cases of MAS are idiopathic (64%), 15% are associated with Mendelian disorders, and 17% are related to inflammatory diseases. Extra-aortic involvement including renal (70%), superior mesenteric (30%), and celiac (22%) arteries is common, especially among those with associated Mendelian disorders. Inferior mesenteric artery involvement is almost never reported. The majority of cases (72%) undergo endovascular or surgical management with residual hypertension reported in 34% of cases, requiring medication or reintervention. Clinical manifestations and extent of extra-aortic involvement are lacking.

CONCLUSIONS

MAS presents with significant involvement of visceral arteries with over two thirds of cases having renal artery stenosis, and one third with superior mesenteric artery stenosis. The extent of disease is worse among those with genetic and inflammatory conditions. Further studies are needed to better understand etiology, long-term effectiveness of treatment, and to determine the optimal management of this potentially devastating condition.

Different Anti-Contractile Function and Nitric Oxide Production of Thoracic and Abdominal Perivascular Adipose Tissues

Divergent phenotypes between the perivascular adipose tissue (PVAT) surrounding the abdominal and the thoracic aorta might be implicated in regional aortic differences, such as susceptibility to atherosclerosis. Although PVAT of the thoracic aorta exhibits anti-contractile function, the role of PVAT in the regulation of the vascular tone of the abdominal aorta is not well defined. In the present study, we compared the anti-contractile function, nitric oxide (NO) availability, and reactive oxygen species (ROS) formation in PVAT and vessel walls of abdominal and thoracic aorta. Abdominal and thoracic aortic tissue from male Wistar rats were used to perform functional and molecular experiments. PVAT reduced the contraction evoked by phenylephrine in the absence and presence of endothelium in the thoracic aorta, whereas this anti-contractile effect was not observed in the abdominal aorta. Abdominal PVAT exhibited a reduction in endothelial NO synthase (eNOS) expression compared with thoracic PVAT, without differences in eNOS expression in the vessel walls. In agreement with this result, NO production evaluated in situ using 4,5-diaminofluorescein was less pronounced in abdominal compared with thoracic aortic PVAT, whereas no significant difference was observed for endothelial NO production. Moreover, NOS inhibition with L-NAME enhanced the phenylephrine-induced contraction in endothelial-denuded rings with PVAT from thoracic but not abdominal aorta. ROS formation and lipid peroxidation products evaluated through the quantification of hydroethidine fluorescence and 4-hydroxynonenal adducts, respectively, were similar between PVAT and vessel walls from the abdominal and thoracic aorta. Extracellular superoxide dismutase (SOD) expression was similar between the vessel walls and PVAT of the abdominal and thoracic aorta. However, Mn-SOD levels were reduced, while CuZn-SOD levels were increased in abdominal PVAT compared with thoracic aortic PVAT. In conclusion, our results demonstrate that the anti-contractile function of PVAT is lost in the abdominal portion of the aorta through a reduction in eNOS-derived NO production compared with the thoracic aorta. Although relative SOD isoforms are different along the aorta, ROS formation, and lipid peroxidation seem to be similar. These findings highlight the specific regional roles of PVAT depots in the control of vascular function that can drive differences in susceptibility to vascular injury.

Extracellular Matrix Disarray as a Mechanism for Greater Abdominal Versus Thoracic Aortic Stiffness With Aging in Primates

OBJECTIVE

Increased vascular stiffness is central to the pathophysiology of aging, hypertension, diabetes mellitus, and atherosclerosis. However, relatively few studies have examined vascular stiffness in both the thoracic and the abdominal aorta with aging, despite major differences in anatomy, embryological origin, and relation to aortic aneurysm.

APPROACH AND RESULTS

The 2 other unique features of this study were (1) to study young (9±1 years) and old (26±1 years) male monkeys and (2) to study direct and continuous measurements of aortic pressure and thoracic and abdominal aortic diameters in conscious monkeys. As expected, aortic stiffness, β, was increased P<0.05, 2- to 3-fold, in old versus young thoracic aorta and augmented further with superimposition of acute hypertension with phenylephrine. Surprisingly, stiffness was not greater in old thoracic aorta than in young abdominal aorta. These results can be explained, in part, by the collagen/elastin ratio, but more importantly, by disarray of collagen and elastin, which correlated best with vascular stiffness. However, vascular smooth muscle cell stiffness was not different in thoracic versus abdominal aorta in either young or old monkeys.

CONCLUSIONS

Thus, aortic stiffness increases with aging as expected, but the most severe increases in aortic stiffness observed in the abdominal aorta is novel, where values in young monkeys equaled, or even exceeded, values of thoracic aortic stiffness in old monkeys. These results can be explained by alterations in collagen/elastin ratio, but even more importantly by collagen and elastin disarray.

Sodium thiosulphate and progression of vascular calcification in end-stage renal disease patients: a double-blind, randomized, placebo-controlled study

BACKGROUND

Sodium thiosulphate (NaTS) is mostly used in haemodialysis (HD) patients with calcific uraemic arteriolopathy. This double-blind, randomized, placebo-controlled study assessed the effect of NaTS on progression of cardiovascular calcifications in HD patients.

METHODS

From 65 screened patients, we recruited 60 patients with an abdominal aorta Agatston calcification score ≥100. Thirty patients were randomized to receive NaTS 25 g/1.73 m2 and 30 patients to receive 100 mL of 0.9% sodium chloride intravenously during the last 15 min of HD over a period of 6 months. The primary endpoint was the absolute change of the abdominal aortic calcification score.

RESULTS

The abdominal aortic calcification score and calcification volume of the abdominal aorta increased similarly in both treatment groups during the trial. As compared with the saline group, patients receiving NaTS exhibited a reduction of their iliac artery calcification score (-137 ± 641 versus 245  ± 755; P = 0.049), reduced pulse wave velocity (9.6  ± 2.7 versus 11.4 ± 3.6; P = 0.000) and a lower carotid intima-media thickness (0.77  ± 0.1 versus 0.83  ±  00.17; P = 0.033) and had better preservation of echocardiographic parameters of left ventricular hypertrophy. No patient of the NaTS group developed new cardiac valve calcifications during the trial as compared with 8 of 29 patients in the saline group. By univariate analysis, NaTS therapy was the only predictor of not developing new valvular calcifications. No adverse events possibly related to NaTS infusion were noted.

CONCLUSIONS

While NaTS failed to retard abdominal aortic calcification progress, it positively affected calcification progress in iliac arteries and heart valves as well as several other cardiovascular functional parameters.

Clinical evaluation for lower abdominal aorta balloon occluding in the pelvic and sacral tumor resection

OBJECTIVE

To investigate the values of clinical application of lower abdominal aorta balloon occluding in the pelvic and sacral tumor resection.

METHOD

From January 2004 to January 2010, 137 patients were diagnosed as sacral or pelvic tumors and underwent surgery in our institution. Forty-five patients underwent resection combined with lower abdominal aorta balloon occluding to control hemorrhage (balloon occluding group), the remaining 92 patients underwent conventional resection (conventional therapy group). We compared operative time, intraoperative hemorrhage, the amount of blood transfusion, postoperative complications, mean hospital stay as well as rates of tumor recurrence or metastasis at 3 years.

RESULTS

En-bloc resection was performed in 93.3% (42/45) patients in balloon occluding group while the conventional therapy group was 78.2% (79/92). The balloon occluding group showed significantly shorter mean operating time, lower blood loss, lower blood transfusion, and lower postoperative drainage volume than did the conventional therapy group. The two treatment groups showed no significant difference in mean hospital stay, frequency of postoperative complications or rates of tumor recurrence or metastasis at 3 years.

CONCLUSION

The application of lower abdominal aorta balloon occluding to control hemorrhage during the surgery contributes to a more clear operation field, less operation time as well as less blood loss and blood transfusion. Moderate prolong of the occluding duration can improve the safety of the surgery and contribute to more radical resection of the tumor without increase of the risks for complications.

Imaging of wall motion coupled with blood flow velocity in the heart and vessels in vivo: a feasibility study

The mechanical property and geometry changes as a result of cardiovascular disease affect both the wall motion and blood flow in the heart and vessels, whereas the latter two are also coupled and therefore continuously influence one another. Simultaneous and registered imaging of both cardiovascular wall motion and blood velocity may thus contribute to more complete computational models of cardiovascular mechanical and fluid dynamics as well as provide additional diagnostic information. The objective of this paper was to determine the feasibility of imaging cardiovascular wall motion coupled with blood flow in vivo. Normal (n = 6) and infarcted (n = 5) murine left ventricles, and normal (n = 5) and aneurysmal (n = 4) murine abdominal aortas, were imaged in longitudinal views with a 30-MHz ultrasound probe. Using electrocardiogram (ECG) gating, 2-D radio-frequency (RF) data were acquired at a frame rate of 8 kHz. The axial wall velocity and blood velocity were estimated using a speckle-tracking technique. Spatially and temporally registered imaging of both cardiovascular wall motion and blood flow was shown to be feasible. Reduced wall motion was detected in the infarcted region, whereas vortex flow patterns were imaged in diastolic phases of both normal and infarcted left ventricles. The myocardial wall motion and blood flow were found to be more synchronous in the normal heart, where the blood moves toward the anteroseptal wall after the mitral valve opens (i.e., rapid filling phase), and the anteroseptal wall simultaneously undergoes outward motion. In the infarcted heart, however, in the rapid filling phase, the basal anteroseptal wall starts moving about 20 ms before the mitral valve opens and the blood enters the left ventricle. In the normal aorta, the wall motion and blood velocity were uniform and synchronous. In the aneurysmal aorta, reduced and spatially varied wall motion and vortex flow patterns in the aneurysmal sac were found. The wall motion and blood velocity were thus less synchronous in the aneurysmal aorta. Cardiovascular wall motion and blood flow were both imaged in mice in vivo. This dual information may provide important insights for the diagnosis of cardiovascular disease as well as essential parameters for its biomechanical modeling.

MR pulse wave velocity increases with age faster in the thoracic aorta than in the abdominal aorta

PURPOSE

To assess the difference between thoracic and abdominal aortic pulse wave velocity (PWV) in apparently healthy subjects including young adults to elderly subjects.

MATERIALS AND METHODS

We performed PWV and distensibility measurements and analysis of thoracic and abdominal aortic segments in 96 apparently normal subjects aged 20-80 years with magnetic resonance (MR). Both unadjusted correlation and General Linear Model (GLM) analysis of log-transformed PWV (thoracic and abdominal aorta) and distensibility (four aortic cross-sections) were performed.

RESULTS

Both thoracic and abdominal PWV values and distensibility values increased with age. In unadjusted analyses the correlation between the ln(thoracic PWV) and age (r = 0.71; P < 0.001) was stronger than between ln(abdominal PWV) and age (r = 0.50; P < 0.001). In GLM analysis, the only determinant of thoracic and abdominal PWV was age (F = 42.5 and F = 14.8, respectively; both P < 0.001). Similarly, correlation between ln(distensibility) and age was strong (r = -0.79, r = -0.67, r = -0.71, and r = -0.65 for ascending, descending, diaphragmatic, and low abdominal aorta, respectively; all P < 0.001). In GLM analysis, age was the major determinant for distensibility of the ascending aorta (F = 81.7; P < 0.001), descending aorta (F = 42.2; P < 0.001), diaphragmatic aorta (F = 39.2; P < 0.001), and low abdominal aorta (F = 32.8; P < 0.001).

CONCLUSION

The thoracic aorta is less stiff than the abdominal aorta in young and middle-aged subjects, and stiffens more rapidly with age than the abdominal aorta, resulting in a stiffer thoracic than abdominal aorta at older age.

Long-term evaluation of vascular grafts with circumferentially aligned microfibers in a rat abdominal aorta replacement model

Long-term results of implants in small animal models can be used to optimize the design of grafts to further promote tissue regeneration. In previous study, we fabricated a poly(ɛ-caprolactone) (PCL) bi-layered vascular graft consisting of an internal layer with circumferentially aligned microfibers and an external layer with random nanofibers. The circumferentially oriented vascular smooth muscle cells (VSMCs) were successfully regenerated after the grafts were implanted in rat abdominal aorta for 3 months. Here we investigated the long-term (18 months) performance of the bi-layered grafts in the same model. All the grafts were patent. No thrombosis, aneurysm, or stenosis occurred. The endothelium maintained complete. However, most of circumferentially oriented VSMCs migrated to luminal surface of the grafts to form a neointima with uniform thickness. Accordingly, extracellular matrix including collagen, elastin, and glycosaminoglycan displayed high density in neointima layer while with low density in the grafts wall because of the incomplete degradation of PCL. A small amounts of calcification occurred in the grafts. The contraction and relaxation function of regenerated neoartery almost disappeared. These data indicated that based on the structure design, many other factors of grafts should be considered to achieve the regenerated neoartery similar to the native vessels after long-term implantation. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2596-2604, 2018.

ANATOMICAL VARIATIONS OF THE CELIAC TRUNK: A SYSTEMATIC REVIEW

INTRODUCTION

The celiac trunk (CT) is one of the abdominal portion branches of the aortic artery and, together with the superior mesenteric and inferior mesenteric arteries, participates in the abdominal viscera vascularization through a series of anastomoses. Absence of CT or variation in the number of terminal branches implies in varied abdominal arteries origins, which may have implication in surgical approaches.

OBJECTIVE

To analyze the anatomical variations of the celiac trunk and possible associated surgical clinical implications.

METHODS

It is a systematic review of articles indexed in the PubMed, Lilacs, SciELO, Springerlink, Scienc Direct and Latindex databases from August to September 2017. Original articles involving the anatomical variations of the celiac trunk in humans were included. The presence/absence of the celiac trunk, the number of terminal branches and the place of origin of its branches in variant cases of the normal anatomical pattern, were considered for this study.

RESULTS

At the end of the research, 12 articles were selected, characterized by sample, anatomical structure evaluation method and main results. The normal anatomical pattern was the most prevalent in most studies (75.0%). CT was absent in 41.7% of the findings. The most prevalent anatomical variation was the presence of CT with bifurcation (66.7%). It was also observed the origin of the common and splenic hepatic arteries from the mesenteric arteries (25.0%). The presence of only one branch (16.7%) and quadrifurcation (8.33%) were other findings.

CONCLUSION

CT variations are not uncommon findings, with different anatomic variants being reported. Thus, the importance of knowing the possible variations of this structure is emphasized, which may have implications for surgical interventions and imaging studies related to the abdominal region.

The prevalence and distribution of the atherosclerotic plaques in the abdominal aorta and its branches

BACKGROUND

The aim of our study was to determine the existence, distribution, type and burden of the atherosclerotic plaques which are found in the abdominal aorta, its branches and the branching points.

MATERIALS AND METHODS

Two hundred and sixty-one patients (117 female, 144 male; mean age 53.34 ± 16.02, range 12-84) who underwent dual-source computed tomography angiography (CTA) were retrospectively analysed. The prevalence and distribution of the plaques in the proximal, middle and distal parts of abdominal aorta and its branches; coeliac trunk, superior and inferior mesenteric arteries, renal arteries, splenic artery and common, external and internal iliac arteries and in the aortic orifices, the type and severity of these plaques and their relations with age and gender were studied.

RESULTS

In our study, 69.3% of the patients had atherosclerotic plaques, mostly at the distal part of abdominal aorta. The existence of the plaques increased with age. The types of these plaques were mixed (43%), calcified (24%) and soft (3%). Mixed and calcified plaques were more common in the abdominal aorta and its branches, respectively. All of the arteries except for inferior mesenteric artery mostly had mild plaques. The plaques at the branching points, which were most frequently localised in the aortic bifurcation, were found in the 41.8% of the patients. The plaques in the branches were usually accompanied by atherosclerosis of abdominal aorta.

CONCLUSIONS

Dual-source CTA enables mapping of atherosclerotic burden in abdominal arteries. Knowing the localisation, type and severity of the atherosclerotic plaques can be important to predict the clinical results and choose the proper treatment.

Greater Volume but not Higher Density of Abdominal Aortic Calcium Is Associated With Increased Cardiovascular Disease Risk: MESA (Multi-Ethnic Study of Atherosclerosis)

BACKGROUND

Abdominal aortic calcium (AAC) and coronary artery calcium (CAC) independently and similarly predict cardiovascular disease (CVD) events. The standard AAC and CAC score, the Agatston method, upweights for greater calcium density, thereby modeling higher calcium density as a CVD hazard.

METHODS AND RESULTS

Computed tomography scans were used to measure AAC and CAC volume and density in a multiethnic cohort of community-dwelling individuals, and Cox proportional hazard was used to determine their independent association with incident coronary heart disease (CHD, defined as myocardial infarction, resuscitated cardiac arrest, or CHD death), cardiovascular disease (CVD, defined as CHD plus stroke and stroke death), and all-cause mortality. In 997 participants with Agatston AAC and CAC scores >0, the mean age was 66±9 years, and 58% were men. During an average follow-up of 9 years, there were 77 CHD, 118 CVD, and 169 all-cause mortality events. In mutually adjusted models, additionally adjusted for CVD risk factors, an increase in ln(AAC volume) per standard deviation was significantly associated with increased all-cause mortality (hazard ratio=1.20; 95% confidence interval, 1.08-1.33; P<0.01) and an increased ln(CAC volume) per standard deviation was significantly associated with CHD (hazard ratio=1.17; 95% confidence interval, 1.04-1.59; P=0.02) and CVD (hazard ratio=1.20; 95% confidence interval, 1.05-1.36; P<0.01). In contrast, both AAC and CAC density were not significantly associated with CVD events.

CONCLUSIONS

The Agatston method of upweighting calcium scores for greater density may be inappropriate for CVD risk prediction in both the abdominal aorta and coronary arteries.

Ultrasound-based Pulse Wave Velocity Evaluation in Mice

Arterial stiffness can be evaluated by calculating pulse wave velocity (PWV), i.e., the speed with which the pulse wave travels in a conduit vessel. This parameter is being increasingly investigated in small rodent models in which it is used for assessing alterations in vascular function related to particular genotypes/treatments or for characterizing cardiovascular disease progression. This protocol describes an image processing algorithm which leads to non-invasive arterial PWV measurement in mice using ultrasound (US) images only. The proposed technique has been used to assess abdominal aorta PWV in mice and evaluate its age-associated changes. Abdominal aorta US scans are obtained from mice under gaseous anesthesia using a specific US device equipped with high-frequency US probes. B-mode and Pulse-Wave Doppler (PW-Doppler) images are analyzed in order to obtain diameter and mean velocity instantaneous values, respectively. For this purpose, edge detection and contour tracking techniques are employed. The single-beat mean diameter and velocity waveforms are time aligned and combined in order to achieve the diameter-velocity (lnD-V) loop. PWV values are obtained from the slope of the linear part of the loop, which corresponds to the early systolic phase. With the present approach, anatomical and functional information about the mouse abdominal aorta can be non-invasively achieved. Requiring the processing of US images only, it may represent a useful tool for the non-invasive characterization of different arterial sites in the mouse in terms of elastic properties. The application of the present technique can be easily extended to other vascular districts, such as the carotid artery, thus providing the possibility to obtain a multi-site arterial stiffness assessment.

Plasma D-dimer as a predictor of the progression of abdominal aortic aneurysm

Essentials D-dimer could provide important information about abdominal aortic aneurysm (AAA) progression. The greatest diameter of the infrarenal aorta and the value of plasma D-dimer were determined. AAA progression is correlated with increasing plasma D-dimer levels. The increasing value of plasma D-dimer could be a predictor of aneurysm progression.

SUMMARY

Background The natural course of abdominal aortic aneurysm (AAA) is mostly asymptomatic and unpredictable. D-dimer could provide potentially important information about subsequent AAA progression. Objectives The aims of this study were to establish the relationship between the progression of an abdominal aortic aneurysm (AAA) and plasma D-dimer concentration over a 12-month period and determine the value of plasma D-dimer in patients with sub-aneurysmal aortic dilatation. Patients/Methods This was a prospective observational study that involved 33 patients with an AAA, 30 patients with sub-aneurysmal aortic dilatation and 30 control subjects. The greatest diameter of the infrarenal aorta, which was assessed by ultrasound, and the value of plasma D-dimer were determined for all subjects at baseline assessment, as well as after 12 months for those with an AAA. Results A positive correlation was found between the diameter of an AAA and plasma D-dimer concentration at the baseline and the control measurement stages. There was a strong positive correlation between AAA progression and increasing plasma D-dimer concentration over a 12-month period. Among patients with sub-aneurysmal aortic dilatation (n = 30), the value of plasma D-dimer was higher compared with matched controls (n = 30). Conclusions There is a strongly positive correlation between AAA progression and increasing plasma D-dimer concentration. The value of plasma D-dimer is higher in patients with sub-aneurysmal aortic dilatation than in control subjects.

Normal abdominal aorta diameter in infants, children and adolescents

BACKGROUND

The normal limits of arterial diameters must be known to diagnose pathologies such as dilatation, stenosis and hypoplasia. Thoracic aorta diameter in childhood has been measured in previous studies, but the number of studies in which normal aortic diameter is determined is very small. The aim of this study was therefore to determine the normal standard diameter of the aorta and iliac arteries in children according to gender and level.

METHODS

Pediatric abdominal computed tomography carried out for various reasons was retrospectively re-evaluated between January 2016 and February 2017. Patients were classified according to age into six groups. Vessel diameter, age, gender and vertebra diameter were evaluated.

RESULTS

Mean proximal aorta diameter was 8.84 mm for 12-36 months, 10.02 mm for 37-84 months, 12.32 mm for 85-132 months, 14.45 mm for 133-180 months, and 16.51 mm for 181-204 months. Mean distal aorta diameter was 6.67 mm for 12-36 months, 8.07 mm for 37-84 months, 10.79 mm for 85-132 months, 12.14 mm for 133-180 months, and 14.01 mm for 181-204 months. The lumen diameter of the abdominal aorta, both proximally and distally, correlated linearly with age as an independent predictor. Similarly, the lumen diameter of the right and left common iliac artery correlated linearly with age as an independent predictor. There was no statistically significant difference in vascular diameter according to gender in any age groups.

CONCLUSIONS

Optimal evaluation of aortic diameter is possible on computed tomography. Measurement outside the normal range is a sign of aneurysm or hypoplasia.

Biocompatibility and Immunogenicity of Decellularized Allogeneic Aorta in the Orthotopic Rat Model

The generation of a small-caliber arterial graft, utilizing a large vessel of a small animal, such as the aorta of the rat or rabbit, for clinical use in the peripheral arterial tree, can widen the options for arterial prostheses. This in vivo study demonstrated the ability of the decellularization protocol that was used to produce a noncytotoxic acellular small-caliber arterial graft, with sufficient biomechanical and biological integrity to withstand the demanding flow and pressure environment of the rat aorta. This work also demonstrated the superiority of the decellularized homograft over its intact counterpart, in terms of lower immunogenicity.

Incidental abdominal aneurysms: a retrospective study of 13,115 patients who underwent a computed tomography scan

We evaluated the frequency and outcomes of abdominal aortic aneurysm (AAA) in Qatar. Data were collected retrospectively between 2004 and 2008 for all adult patients who underwent abdominal computed tomographic scanning for any reason. Patients with AAA were followed up for 3 years for aneurysmal rupture and mortality. Of the 13,115 patients screened, 61 (0.5%) patients had abdominal aneurysms. Most (82%) patients with AAA were male with mean age of 67 ± 12 years. The incidence of AAA substantially increased with age. Cardiovascular risk factors were prevalent among patients with AAA. The main location of AAA was infrarenal (67%), followed by thoracoabdominal (23%). The mean AAA diameter was 5.3 ± 2.5 cm. The rate of AAA rupture was 8% with a mortality rate of 60%; 80% of these were infrarenal, and 80% of them had a diameter of ≥5.5 cm. Overall mortality was 33%. This large study addressed the impact of screening for AAA in a population with high cardiovascular burden.

Endovascular therapy for penetrating ulcers of the infrarenal aorta

BACKGROUND

We sought to investigate the short- and mid-term results of the endovascular repair of infrarenal abdominal penetrating aortic ulcers (aPAUs).

METHODS

Patients with infrarenal aPAUs treated by endovascular means between March 2004 and June 2012 were recruited. Pre-interventional imaging included computed tomography (CT) or CT angiography. Endoprostheses were chosen and deployed according to standard elective endovascular aneurysm repair anatomical requirements. Endpoints included 30-day survival, in-hospital mortality, 1-year PAU-related mortality, 1-year all-cause mortality, freedom from death and freedom from cumulative complication and interventions. Statistically, the Kaplan-Meier method was applied.

RESULTS

Nineteen patients (18 men, median age 70 years (interquartile range, IQR = 59-75)) suffering aPAUs (n = 29, infrarenal = 25) were detected. The median co-morbid severity scoring was 1.0 (IQR = 0.4-1.4). The median follow-up period was 33 months (IQR = 8-51.5). Furthermore, 94.7% of patients had hypertension. Fourteen patients (73.7%) had symptoms, including four of them admitted with shock from large-contained PAU rupture. Endoluminal stent grafting was successfully delivered in all patients. In-hospital mortality was 10.5%. Two patients required secondary interventions (10.5%). The 30-day survival, 1-year PAU-related mortality and 1-year all-cause mortality were 94.7%, 89.5% and 89.5%, respectively. Freedom from death and freedom from cumulative complications and interventions was 86.4% and 86.4%, 78.9% and 78.9%, and 67.9% and 71.2% at 12, 24 and 36 months, respectively.

CONCLUSIONS

Urgent and elective endovascular repair of aPAUs can be achieved with high technical success. The significant co-morbid status of the treated patients is illustrated in the considerable in-hospital mortality and underlines the advantage of such treatment over open surgical repair.

Detection of carotid artery calcification on the panoramic images of post-menopausal females is significantly associated with severe abdominal aortic calcification: a risk indicator of future adverse vascular events

OBJECTIVES

Outcome studies among post-menopausal females with calcified carotid artery plaque (CCAP) on their panoramic images have not been previously undertaken. We sought to compare the extent of abdominal aortic calcification (AAC) on lateral lumbar spine radiographs (LLSRs), among groups of females with (CCAP+) and without (CCAP-) carotid lesions on their panoramic images. "Severe" levels of AAC have previously been validated as a risk indicator of future adverse cardiovascular events.

METHODS

This cross-sectional case-control study included a "CCAP+ group" consisting of females more than 50 years of age having the carotid lesion diagnosed by their dentists and an atherogenic risk factor (age, body mass index, hypertension, diabetes and dyslipidaemia)-matched "CCAP- group". A physician radiologist, using the Framingham index, evaluated the LLSRs for the magnitude of AAC. Summary statistics for key variables were computed and conditional logistic regression techniques were considered.

RESULTS

Members of the CCAP+ group were significantly (p=0.038) more likely to demonstrate "severe" levels of AAC on their LLSRs than members of the CCAP group.

CONCLUSIONS

This is the first published study demonstrating that CCAP on panoramic images of post-menopausal females is significantly associated with "severe" levels of AACs on LLSRs independent of traditional risk factors. Given that these levels of AAC are a validated risk indicator of future myocardial infarction and stroke, dentists must evaluate the panoramic images of post-menopausal females for the presence of CCAP. Patients with carotid atheromas should be referred to their physicians for further evaluation given the systemic implications.

Anterior retroperitoneal rami: until now unnamed direct branches of the abdominal aorta

The aim of the study was to gain a thorough knowledge of the topography and distribution of until now officially unnamed minute direct branches from abdominal aorta, stemming from its ventral and lateral aspects, supplying surrounding tissue, and to comprise it to the existing studies. The study was performed in fixed cadaverous material collected from India ink injections of abdominal aorta samples with large surrounding retroperitoneal tissue. The 25 samples were dissected under magnifying binocular glass, followed by graphic reconstruction; statistical analysis, and the study was preceded with detailed review of branches from abdominal aorta. For systematization of the segmental anatomy of the abdominal aorta and infrarenal segment of inferior vena cava, we defined three levels in this area. The retroperitoneal branches were most frequently situated simultaneously within all three predefined levels according to renal and inferior mesenteric arteries origin. There were 18% of retroperitoneal branches within Level 1, 39% within Level 2 and 43% within Level 3. They were branches not only from the abdominal aorta, but also from the testicular/ovarian artery, common iliac artery and in one case from the right accessory renal artery. Paired arrangement was recorded mainly cranially to the origin of inferior mesenteric artery, unpaired branches were more frequently found caudally. In conclusion, due to the terminological disunity of these arteries in the clinical literature and total absence in the anatomical literature, we propose to denominate them as anterior retroperitoneal branches of abdominal aorta (rami retroperitoneales anteriores aortae abdominalis).

Single-center experience with simultaneous thoracic endovascular aortic repair and abdominal endovascular aneurysm repair

Objective To evaluate the efficacy and outcomes of simultaneous thoracic endovascular aortic repair (TEVAR) and abdominal endovascular aneurysm repair (EVAR). Methods A total of 21 patients (20 men; mean 65 ± 7 years, range 54-77) underwent simultaneous TEVAR and EVAR between September 2010 and June 2015 at a single center were retrospectively reviewed. All patients had concomitant thoracic pathologies (aneurysm, penetrating aortic ulcer, intramural hematoma, or dissection) and abdominal aortic aneurysm. The abdominal aneurysms diameters ranged from 5.9 cm to 10 cm. Thoracic lesions in 17 patients were complicated with acute aortic syndrome, and the remainders had indications for simultaneous repair. All patients were followed up postoperative at 1 month, 6 months, and yearly thereafter. Technique success, procedure-related complications were evaluated. Results All patients received local anesthesia, perioperative relative high arterial pressure (above 130/80 mmHg) maintenance, and prophylactic high-dose corticosteroid. The technical success rate was 100%. Average procedural time was 157.6 ± 45.6 min. The length of thoracic coverage was 20.4 ± 4.7 cm (range 15-27). Two patients required left subclavian artery coverage during TEVAR and two patients required lowest renal artery coverage during EVAR. Chimney stents were deployed simultaneously. Patients were followed between 2 and 59 months postoperatively. No patients developed acute cardiopulmonary complications and contrast-induced nephropathy. Two patients developed transient lower extremity weakness that resolved with blood pressure elevation, cerebrospinal fluid drainage, and intravenous drips of high-dose corticosteroid. The average hospital stay was 10.7 ± 7.9 days (range 4-30). During follow-up, one patient died of aneurysm rupture at postoperative 6 months, two patients developed type Ib endoleak at 9 months and 48 months respectively, one was successfully sealed with iliac stent-graft extension, the other received conservative treatment and is symptom free till now. Conclusion Combined TEVAR and EVAR can be performed safely with minimal morbidity and mortality. When anatomically feasible, simultaneous TEVAR and EVAR can be considered as an acceptable alternative for multilevel aortic diseases.

All dangerous types of endoleaks after endovascular aneurysm repair in a single patient

Endovascular aneurysm repair (EVAR) has become tremendously popular in recent years. However, the long-term results of these stent grafts are uncertain and are still being evaluated. According to some data, the graft-related complication rate after EVAR could be as high as 43% in long-term observation. In this case report, we present a patient who had all dangerous types of endoleaks after EVAR and required sophisticated management including endovascular and open surgical repairs. After repeated invasive treatment, it was possible to exclude all endoleaks, and now the patient is free from graft-related complications. Although EVAR has become very popular, we should remember about possible complications, which could be very severe and life-threatening. For this reason, the choice between endovascular and open repair of abdominal aortic aneurysm should be well considered.

A cadaveric study of the testicular artery and its clinical significance

Background

Knowledge of testicular artery variations is vital to ensure that they are not neglected during a variety of different operative techniques, since damage can cause testicular atrophy.

Objectives

The present study was therefore intended to identify variants in the origin and course of the testicular arteries. An attempt was made to classify the arteries based on their various origins.

Methods

This study examined 42 formalin-fixed cadavers of 40 to 70-year-old adult males. Variant origins of the testicular artery were identified and classified. Variations in the origin and course of the artery were colored, photographed, and documented. The distances between the origins of the testicular arteries and the mid-points of the origins of the renal arteries were measured.

Results

Testicular arteries were classified into four categories on the basis of origin. This variability was defined in relation to the renal and inferior mesenteric arteries. The mean distance between the origin of the testicular artery and the mid-point of the origin of the renal artery were 3.08 and 3.47 cm, on the right and left sides respectively. Variations were almost exclusively found on the left side. The variations observed included multiple arterial twigs forming the testicular artery, suprarenal arteries arising from the testicular artery, and testicular artery duplication.

Conclusion

This study provides an insight into variations in the testicular artery and proposes a classification which could help surgeons during a variety of procedures on the male abdomen and pelvis.

Evaluation of the impact of passive smoke on arterial elasticity via echo-tracking technology in a rabbit model

OBJECTIVES

The purpose of this study was to evaluate the elasticity of the abdominal aorta in passively smoking rabbits using echo-tracking technology and pathologic examination.

METHODS

Fifty-four male New Zealand White rabbits were randomly divided into a passive smoking group and a normal control group. The elasticity indicators for the abdominal aorta of the rabbits were measured by means of echo tracking, which was performed before and 1, 2, and 3 months after passive smoking. Measured indicators included the pressure-strain elastic modulus, stiffness, arterial compliance, augmentation index, and pulse wave velocity. After the completion of the in vivo measurements, rabbits were euthanized randomly, and the corresponding arterial sites were resected for pathologic examination and in vitro measurement of vascular elasticity.

RESULTS

The echo-tracking technology used in our research proved that the elastic modulus, stiffness, and pulse wave velocity gradually increased with time by passive smoking, whereas arterial compliance decreased by passive smoking. Pathologic examination and in vitro measurements were performed and further confirmed the observed in vivo results.

CONCLUSIONS

Passive smoking can injure arteries and reduce arterial elasticity. Echo-tracking technology is an accurate, noninvasive, and reliable method for analysis of the impact of passive smoking on arterial elasticity and detection arterial injury, which also can provide a new instructional basis for prevention and treatment of several arterial diseases.

The effects of nicotine administration on the pathophysiology of rat aortic wall

Abdominal aortic aneurysm (AAA) is the progressive dilation of the abdominal aorta. Nicotine is reported to be associated with the development and rupture of AAA, but the pathological effects of nicotine on normal rat aorta have not been determined. We investigated pathological changes in the aortic wall of rats caused by the administration of nicotine. Nicotine administration weakened the vascular wall, increased gelatinolytic activity and promoted the destruction of elastin and collagen in the rat abdominal aorta. There were no differences in the areas positive for matrix metalloproteinase (MMP)-2 and MMP-9 between the control and nicotine treated groups. The areas positive for MMP-12 in the nicotine group were significantly greater than for the control group. Gelatinolytic activity in the aortic wall was increased significantly in the nicotine group. Our findings suggest that MMP-12 is sensitive to nicotine exposure in rats.

Optimization of pseudo-continuous arterial spin labeling for renal perfusion imaging

PURPOSE

To evaluate labeling efficiency of pseudo-continuous arterial spin labeling (PCASL) and to find the gradient parameters that increase PCASL robustness for renal perfusion measurements.

METHODS

Aortic blood flow was characterized in 3 groups: young healthy volunteers (YHV1), chronic kidney disease (CKD) patients (CKDP), and healthy controls (HCO). PCASL inversion efficiency was evaluated through numeric simulations considering the measured pulsatile flow velocity profiles and off-resonance effects for a wide range of gradient parameters, and the results were assessed in vivo. The most robust PCASL implementation was used to measure renal blood flow (RBF) in CKDP and HCO.

RESULTS

Aortic blood velocities reached peak values of 120 cm/s in YHV1, whereas for elderly subjects values were lower by approximately a factor of 2. Simulations and experiments showed that by reducing the gradient average (G_ave ) and the selective to average gradient ratio (G_max /G_ave ), labeling efficiency was maximized and PCASL robustness to off-resonance was improved. The study in CKDP and HCO showed significant differences in RBF between groups.

CONCLUSION

An efficient and robust PCASL scheme for renal applications requires a G_max /G_ave ratio of 6-7 and a G_ave value that depends on the aortic blood flow velocities (0.5 mT/m being appropriate for CKDP and HCO).