Aortic Length Research Articles

Free margin length and geometric height in aortic root dilatation and leaflet prolapse: implications for aortic valve repair surgery.

Our goal was to assess the aortic leaflet free margin length (FML) and geometric height (gH) in a normal aortic valve (AV), aorta dilatation and aortic leaflet prolapse. We measured the FML and gH intraoperatively in 132 patients operated on for aortic insufficiency, aortic dilatation, endocarditis or fibroelastoma. Patients were divided into 3 groups: normal tricuspid AV (group 1, n = 12), aortic dilatation (group 2, tricuspid = 43, bicuspid = 18) and leaflet prolapse (group 3, tricuspid = 32, bicuspid = 27). The FML and gH were compared between the groups and between the leaflets within each group. In a normal tricuspid AV, the mean FML and gH were 34.7 ± 3.1 mm and 18.8 ± 1.7 mm, respectively. In group 2 tricuspid, the FML and gH were greater than those in group 1 (FML 43.7 ± 4.4, P < 0.001; gH 21.2 ± 1.8, P = 0.003). In group 3, tricuspid, the FML of the prolapsing leaflet was greater than the FML of the non-prolapsing leaflet (48.3 ± 5.4 vs 42.2 ± 3.6; P < 0.001). In group 2, bicuspid, FML of both leaflets were similar in group 2, but augmented on the fused leaflet compared to the non-fused leaflet in group 3 (fused 55.4 ± 6.3; non-fused 46.2 ± 6.2; P < 0.001). In groups 2 and 3 bicuspid, the gH of the non-fused leaflet was systematically greater than the fused leaflet (group 2 non-fused 24.6 ± 2.5 vs fused 20.4 ± 2.1; P < 0.001). In aortic dilatation and leaflet prolapse, FML and, to a lesser extent, gH increased significantly compared to those of normal AV function. FML and gH dimensions also depended on the valve configuration (tricuspid/bicuspid). These data provide new insight into the pathomorphology of AV disease and will serve to further develop new methods of AV repair based on intraoperative measurements of the FML.

Association between aortic telomere length and cardiac post-transplant allograft function

BackgroundIn patients having undergone orthotopic heart transplantation, a number of complications exist that are known to be connected to both telomerase activity and telomere length. The aim of this study was to determine how telomere length in aortic DNA correlates with the subsequent post-transplantation development of the patients. Materials and methodsBetween 2005 and 2015, we collected aortic samples from 376 heart recipients (age 50.8 ± 11.8 years) and 383 donors (age 38.6 ± 12.2 years). Relative telomere length in aortic tissue DNA was determined using quantitative PCR. ResultsShorter telomere length was detected in heart allograft recipients compared to donors (P < 0.0001). Patients suffering acute cellular rejection had significantly shorter telomere length (P < 0.01) than patients without rejection. Shorter telomere length was observed in patients with implanted mechanical circulatory support before heart transplantation (P < 0.03), as well as in subjects with cardiac allograft vasculopathy (P < 0.05). Overall survival time after heart transplantation was associated with shorter donor telomeres (P < 0.004). ConclusionsTelomere length differed between donors and recipients independent of the sex and age of the patients. Our findings suggest a potential new linkage between the aortic telomere length of recipients and post-heart transplant complications. Further studies focusing on epigenetic modifications and gene regulation involved in telomere maintenance in transplanted patients should verify our results.

Sex differences in left ventricular afterload and diastolic function are independent from the aortic size.

BackgroundWomen have a greater risk of heart failure with preserved ejection fraction (HFPEF) than men do, yet the basis for this disparity remains unclear. Greater arterial stiffness and afterload causes left ventricular (LV) diastolic dysfunction, a central mechanism of HFPEF. Because of smaller body habitus, previous reports have used body surface area as a surrogate of the size of the aorta. We performed a comprehensive hemodynamic evaluation of elderly patients with preserved EF and evaluated sex differences in the associations between LV function and afterload, before and after adjusting for the aortic sizes.Methods and resultsFour hundred and forty-three patients (mean age: 73 years, 169 women) who underwent clinically indicated echocardiography and computed tomography (CT) were identified. Linear regression analyses were performed to assess the independent contributions of sex to and its interaction with LV function before and after adjusting for CT-derived aortic length and volume. Although blood pressures were similar between the sexes, women had greater arterial elastance, lower arterial compliance, and greater LV ejection fraction (all p<0.001). Sex differences were detected in the associations between LV afterload and relaxation (mitral e′) as well as in the left atrial (LA) emptying fraction, but not in LA size. These differences remained significant after adjusting for the aortic length and volume. Sensitivity analyses in an age-matched subgroup (n = 324; 162 of each sex) confirmed the robustness of these sex disparities in LV diastolic function and afterload.ConclusionWomen had worse LV relaxation than men did against the same degree of afterload, before and even after adjusting for the aortic sizes.

Mid-term outcomes of endovascular aneurysm repair in challenging aortic neck anatomy based on experience from the GREAT C3 registry.

The European C3 module of the Global Registry for Endovascular Aortic Treatment (GREAT) evaluates the outcome and deployment mechanism of the C3 Gore Excluder stent-graft. We aimed to assess the mid- to long-term durability of the C3 Gore Excluder stent-graft in the management of challenging aortic neck morphology, outside the instruction of use (IFU). The prospectively collected data from GREAT were retrospectively analyzed. For each subject demographic, pre/intra- and postoperative variables were collected. The main outcomes measured were serious adverse events (device-related, cerebrovascular, cardiac, pulmonary, pulmonary embolism, limb ischemia, and renal complications) and re-intervention at the 6-year follow-up. In this study, outside IFU was defined as aortic neck length <15 mm and/or aortic neck angle >60°. A total of 399 subjects (86.7% male, mean age 73.9 years) were identified. Sixty-eight subjects (17%) from 11 recruiting sites underwent endovascular aneurysm repair (EVAR) outside IFU, and 399 devices were implanted. Of these, 47% had neck length <15 mm, 72.3% had neck angulation > 60°, and 21% had both. Mean follow-up duration was 53.5 months (SD=22.3). At the 6-year follow-up, the group with challenging anatomy required significantly more re-interventions (23.5% vs. 13.3%, P<0.05) and reported more serious adverse events (42.6% vs. 30.6%, P<0.005) than those within IFU. Midterm outcomes of the C3 Gore Excluder stent-graft are safe and effective within IFU. Outside IFU patients required significantly more all or device related re-interventions; however, they did not sustain significantly more serious adverse events.

Quantification of aortic pulse wave velocity from a population based cohort: a fully automatic method

BackgroundAortic pulse wave velocity (PWV) is an indicator of aortic stiffness and is used as a predictor of adverse cardiovascular events. PWV can be non-invasively assessed using magnetic resonance imaging (MRI). PWV computation requires two components, the length of the aortic arch and the time taken for the systolic pressure wave to travel through the aortic arch. The aortic length is calculated using a multi-slice 3D scan and the transit time is computed using a 2D velocity encoded MRI (VE) scan. In this study we present and evaluate an automatic method to quantify the aortic pulse wave velocity using a large population-based cohort.MethodsFor this study 212 subjects were retrospectively selected from a large multi-center heart-brain connection cohort. For each subject a multi-slice 3D scan of the aorta was acquired in an oblique-sagittal plane and a 2D VE scan acquired in a transverse plane cutting through the proximal ascending and descending aorta. PWV was calculated in three stages: (i) a multi-atlas-based segmentation method was developed to segment the aortic arch from the multi-slice 3D scan and subsequently estimate the length of the proximal aorta, (ii) an algorithm that delineates the proximal ascending and descending aorta from the time-resolved 2D VE scan and subsequently obtains the velocity-time flow curves was also developed, and (iii) automatic methods that can compute the transit time from the velocity-time flow curves were implemented and investigated. Finally the PWV was obtained by combining the aortic length and the transit time.ResultsQuantitative evaluation with respect to the length of the aortic arch as well as the computed PWV were performend by comparing the results of the novel automatic method to those obtained manually. The mean absolute difference in aortic length obtained automatically as compared to those obtained manually was 3.3 ± 2.8 mm (p < 0.05), the manual inter-observer variability on a subset of 45 scans was 3.4 ± 3.4 mm (p = 0.49). Bland-Altman analysis between the automataic method and the manual methods showed a bias of 0.0 (-5.0,5.0) m/s for the foot-to-foot approach, -0.1 (-1.2, 1.1) and -0.2 (-2.6, 2.1) m/s for the half-max and the cross-correlation methods, respectively.ConclusionWe proposed and evaluated a fully automatic method to calculate the PWV on a large set of multi-center MRI scans. It was observed that the overall results obtained had very good agreement with manual analysis. Our proposed automatic method would be very beneficial for large population based studies, where manual analysis requires a lot of manpower.

Computer modeling in mechanics of circulation

Some cardiovascular pathology connected with variations in geometry, wall properties and microcirculatory disorders can be studied by computer simulations. The mathematical model that allows to calculate the parameters of blood circulation – velocities of blood and pressure, displacements of the artery walls - for a complex vascular tree in real time is proposed.The geometrical model is based on the detailed postmortem measurements on the systemic arterial trees (more than 1000 arterial segments). The aortic model consists of 32 aortic segments and 59 side branches of the aorta including the larger and medium vessels. Mathematical model of blood flow in the system is described by Womersley model of the pulsatile viscous flow in the viscoelastic tube using the pressure and volumetric rate continuity conditions at the bifurcations of arteries. The Windkessel and structured tree outflow boundary conditions at the outlets of the branches have been used. The solution has been found as superposition of the forward and backward running waves. Based on the model, blood circulation parameters were calculated in the aortic model (91 tubes). The calculation results correspond to in vivo measurements. It was shown most of the branches have zero wave reflection coefficients but the large branches like celiac, renal and iliac arteries could produce noticeable wave reflections. The smaller branches possess negative wave reflection coefficient and, thus, contribute to the blood suction effect and lower aortic resistance to the blood flow. It is shown, the individual geometry plays an essential role in the location of the positive and negative wave reflection sites along the aorta and, thus, in the pressure and flow patterns and blood distribution into the branches. The influence of occlusion of the iliac arteries, low/high wall rigidity, and total length of aorta are studied on different individual geometries. The model can be used for determination of the individual parameters for patient-specific cardiovascular models and further modeling of the outcomes of the surgical and therapeutic procedures.

Aortic root changes before and after surgery for chronic aortic dilatation: A 3D echocardiographic study.

Quantitative 3D assessment of the aortic root may improve planning and success of aortic valve (AV)-sparing operations. To use 3D transesophageal echocardiography (TEE) to assess the effect of chronic aortic dilatation on aortic root shape and aortic regurgitation (AR) severity and to examine the effects of AV-sparing operations. To determine the changes with chronic aortic dilatation, we studied 48 patients, 23 with aortic dilatation (Group 1≤mild AR, n=13; Group 2≥moderate AR, n=10) and 25 Controls. To determine the changes in AV-sparing operations, a subgroup of 15 patients were examined pre- and post surgery. 3D-TEE images were analyzed using multiplanar reconstruction (QLAB, Philips, Philips Medical Systems, Andover, MA, USA) to obtain aortic root areas, diameters, and lengths. We also calculated a novel parameter called total coaptation surface area (TCoapSA), which sums the contact surface area of all the AV cusps. Compared to Controls, Groups 1 and 2 had significantly larger aortic root areas, inter-commissural distances, and cusp heights. Compared to Group 1 and Controls, Group 2 had significantly smaller TCoapSA when adjusted for aortic annular area (P=0.001) with shorter coaptation height (P<0.001). In patients undergoing AV-sparing surgery, TCoapSA was significantly larger post surgery (P=0.001) with greater coaptation height (P<0.001) and smaller inter-commissural distances (P<0.001). The aortic valve is a dynamic structure that remodels in response to aortic dilatation. Successful valve-sparing surgery corrects these changes. Quantitative modeling of the aortic valve and root could potentially improve the repair to the individual patients and modify outcomes.

Sex as an independent risk factor for long-term survival after endovascular aneurysm repair

BackgroundSeveral vascular surgical procedures, including repair of abdominal aortic aneurysms (AAAs), show poorer outcomes for women than for men. We evaluated the impact of sex-based demographic differences on survival after endovascular aneurysm repair (EVAR). MethodsWe reviewed EVARs performed at our institution between 2003 and 2009 and assessed aortic neck variables (length, diameter, angulation, and calcification), iliac artery variables (length, tortuosity, angulation, and calcification), and AAA diameter. Cox proportional hazards models were used to examine the association between sex and 5-year mortality while adjusting for patients' demographics, comorbidities, anatomic variables, and AAA parameters. The final model adjusted for sex, age, body mass index, hypertension, iliac artery length, and aortic neck length. ResultsOf 336 patients, 278 were male (mean age, 73 years) and 58 were female (mean age, 77 years; P = .0005). Men had more coronary artery bypass grafts (79 vs 8; P = .02) and percutaneous coronary interventions (52 vs 4; P = .03) than women did. Significant differences between the sexes was seen for aortic neck angle, diameter, and length and for iliac artery diameter and length. Men (44%) were more likely than women (22%; P = .0002) to have EVAR performed within the device guidelines. Five-year survival was 73% in men and 49% in women. Multivariable analysis showed that female sex, increase in age, low body mass index (<25 kg/m2), and aortic neck length were significantly associated with risk of 5-year mortality. ConclusionsWomen presented at an older age and with a more hostile anatomy. They had reduced survival compared with men after EVAR. After controlling for comorbidities and aortic neck and iliac artery anatomy, sex remained an independent predictor for survival.

Anatomical Predictors of Endoleaks or Migration After Endovascular Aneurysm Sealing

Purpose: To identify preoperative anatomical aortic characteristics that predict seal failures after endovascular aneurysm sealing (EVAS) and compare the incidence of events experienced by patients treated within vs outside the instructions for use (IFU). Methods: Of 355 patients treated with the Nellix EndoVascular Aneurysm Sealing System (generation 3SQ+) at 3 high-volume centers from March 2013 to December 2015, 94 patients were excluded, leaving 261 patients (mean age 76±8 years; 229 men) for regression analysis. Of these, 83 (31.8%) suffered one or more of the following events: distal migration ⩾5 mm of one or both stent frames, any endoleak, and/or aneurysm growth >5 mm. Anatomical characteristics were determined on preoperative computed tomography (CT) scans. Patients were divided into 3 groups: treated within the original IFU (n=166), outside the original IFU (n=95), and within the 2016 revised IFU (n=46). Categorical data are presented as the median (interquartile range Q1, Q3). Results: Neck diameter was significantly larger in the any-event cohort vs the control cohort [23.7 mm (21.7, 26.3) vs 23.0 mm (20.9, 25.2) mm, p=0.022]. Neck length was significantly shorter in the any-event cohort [15.0 mm (10.0, 22.5) vs 19.0 mm (10.0, 21.8), p=0.006]. Maximum abdominal aortic aneurysm (AAA) diameter and the ratio between the maximum AAA diameter and lumen diameter in the any-event group were significantly larger than the control group (p=0.041 and p=0.002, respectively). Regression analysis showed aortic neck diameter (p=0.006), neck length (p=0.001), and the diameter ratio (p=0.011) as significant predictors of any event. In the comparison of events to IFU status, 52 (31.3%) of 166 patients in the inside the original IFU group suffered an event compared to 13 (28.3%) of 46 patients inside the 2016 IFU group (p=0.690). Conclusion: Large neck diameter, short aortic neck length, and the ratio between the maximum AAA and lumen diameters are preoperative anatomical predictors of the occurrence of migration (⩾5 mm), any endoleak, and/or aneurysm growth (>5 mm) after EVAS. Even under the refined 2016 IFU, more than a quarter of patients suffered from an event. Improvements in the device seem to be necessary before this technique can be implemented on a large scale in endovascular AAA repair.

Proximal Bare Stent May Reduce Bird-Beak Configuration, Which is Associated with Distal Migration of Stent Graft in the Aortic Arch

Prior studies have shown that a bird-beak configuration causes serious complications after thoracic endovascular aortic repair (TEVAR). However, factors that cause bird-beak configurations are poorly understood. The purpose of this study was to assess the influences of anatomical and device-related factors on bird-beak configuration. Sixty-eight consecutive patients (47 men, mean age, 72.8±9.8years) who underwent TEVAR with proximal fixation in zones 1 to 3 from March 2009 to February 2017 were included. Preoperative and postoperative computed tomography (CT) scans were retrospectively reviewed. Relationships between the incidence of a bird-beak configuration, preoperative aortic arch morphology, and type of stent graft were estimated. The influence of a bird-beak configuration on endograft migration over time was also estimated for 47 patients who underwent CT 12months after TEVAR. The patients' aortic arch pathologies included 52 aneurysms, 11 aortic dissections, 4 pseudoaneurysms, and 1 patent ductus arteriosus. Stent grafts with (the proximal bare stent group [PBS group]) and without (the nonbare stent group [NBS group]) a proximal bare stent were implanted in 24 and 44 patients, respectively. A bird-beak configuration was detected in 30 patients (mean length ± standard deviation [SD], 6.2±3.4mm; mean angle ± SD, 31.7±14.7°) and was significantly more frequent in the NBS group (n=29) than in the PBS group (n=1) (P<0.001). Proximal landing zone, aortic lengths, and aortic arch morphology, including the radius, tortuosity, and angulation of aortic arch curvature, were not associated with the bird-beak configuration. The migration distance after 1year was significantly longer in patients with a bird-beak configuration (3.5±6.1mm) than in patients without a bird-beak configuration (0.5±1.0mm) (P=0.015). This study demonstrated that in aortic arch TEVAR, the use of stent graft with a proximal bare stent may reduce bird-beak configuration, which is associated with distal migration of the stent graft during follow-up.

Aortic arch tortuosity, a novel biomarker for thoracic aortic disease, is increased in adults with bicuspid aortic valve

IntroductionArterial tortuosity has emerged as a predictor of adverse outcomes in congenital aortopathies using 3D reconstructed images. We validated a new method to estimate aortic arch tortuosity on 2D CT. We hypothesize that arch tortuosity may identify bicuspid aortic valve (BAV) patients at high risk to develop thoracic aortic aneurysms or aortic dissections (TAD). MethodsBAV subjects with chest CT scans were retrospectively identified in our clinical records and matched to tricuspid aortic valve (TAV) controls by age, gender, and presentation with TAD. Subjects with prior ascending aortic intervention were excluded. Measurements included aortic arch tortuosity, length, angle, width and height. Total aortic tortuosity was estimated in subjects with available abdominal images. Results120 BAV and 234 TAV subjects were included. Our 2D measurements were highly correlated with 3D midline arch measurements and had high inter- and intra-observer reliability. Compared to TAV, BAV subjects had increased arch tortuosity (median 1.76 [Q1-Q3: 1.62–1.95] vs. 1.63 [1.53–1.78], P < 0.01), length (149 [136–160] vs. 135 [122–152] mm, P < 0.01), height (46 [41–53] vs. 39 [34–47] mm, P < 0.01), and vertex acuity (70 [61–77] vs. 75 [68–81] degree, P < 0.01). In a multivariable analysis, arch tortuosity remained independently associated with BAV after adjusting for aortic diameter and other clinical characteristics. ConclusionsWe found that aortic arch tortuosity is significantly increased in BAV and may identify BAV patients who are at increased risk for TAD. Further studies to evaluate the association between tortuosity and clinical outcomes are in progress.

3D aortic morphology and stiffness in MRI using semi-automated cylindrical active surface provides optimized description of the vascular effects of aging and hypertension

BackgroundClinically, aortic geometry assessment is mainly based on the measurement of maximal diameters at different anatomic locations, which are subsequently used to indicate prophylactic aortic surgery. However, 3D evaluation of aortic morphology could provide volumetric quantification, which integrates both aortic dilatation and elongation and might thus be more sensitive to early geometric changes than diameters. Precise aortic morphology is also required for the calculation of pulse wave velocity (PWVMRI), an established marker of aortic stiffness. Accordingly, we proposed a 3D semi-automated analysis of thoracic aorta MRI data optimizing morphological and subsequent stiffness assessment. MethodsWe studied 74 individuals (40 males, 50 ± 12years): 21 healthy volunteers and 53 patients with hypertension in whom aortic 3D MRI angiography and 2D + t phase-contrast and cine imaging were performed. A semi-automated method was proposed for volumetric aortic segmentation and was evaluated by studying resulting measurements (length, diameters, volumes and PWVMRI) in terms of: 1) reproducibility, 2) correlations with well-established 2D aortic length and diameters, 3) associations with age, carotid-femoral PWV (cf-PWV) and presence of hypertension. ResultsThe measurements obtained with the proposed method were reproducible (coefficients of variation ≤ 5.1%) and were highly correlated with 2D measurements (arch length: r = 0.80, Bland-Altman mean bias [limits]: 2.7 mm [-25; 30]; PWVMRI: r = 0.95, 0.22 m/s [-1.9; 2.4]). Higher or similar correlations with age were found for the proposed 3D method compared to the 2D approach (arch length: r = 0.47 (2D), r = 0.60 (3D); PWVMRI: r = 0.63 (2D), r = 0.64 (3D)). Moreover, a significant association was found between PWVMRI and cf-PWV (r = 0.49, p < 0.001). All aortic measurements increased with hypertension (p < 0.05) and with age: arch length (+9mm/decade); diameters: ascending (+1.2mm/decade) and descending aorta (+1.0mm/decade); volumes: ascending (+2.6mL/decade) and descending aorta (+4.0mL/decade); PWVMRI (+1.7 m s−1/decade). ConclusionsA semi-automated method based on cylindrical active surfaces was proposed for the 3D segmentation of the aorta using a single MRI dataset, providing aortic diameters at anatomical landmarks, aortic volumes and the aortic centerline length used for PWV estimation. Such measurements were reproducible and comparable to expert measurements, which required time-consuming centerline delineation. Furthermore, expected relationships with age and hypertension were found indicating the consistency of our measurements.

Behaviour and motor performance in a cognitive-motor task during learning processes: evidence from EEG network analysis

Thoracic endovascular aortic repair (TEVAR) has dramatically expanded treatment options for patients with thoracic aortic pathology. The interaction between endografts and the dynamic anatomy of the thoracic aorta is not well characterized for repetitive physiologic stressors and subsequent issues related to long-term durability. Through three-dimensional (3D) modeling we sought to quantify cardiac-induced aortic deformation before and after TEVAR to assess the impact of endografts on dynamic aortic anatomy.Eight patients with acute (n = 4) or chronic (n = 3) type B dissections, or chronic arch aneurysm (n = 1), underwent TEVAR with a single (n = 5) or multiple (n = 3) Gore C-TAG(s). Cardiac-resolved thoracic CT images were acquired pre- and post-TEVAR. 3D models of thoracic aorta and branch vessels were constructed in systole and diastole. Axial length, mean, and peak curvature of the ascending aorta, arch, and stented lumens were computed from the aortic lumen centerline, delineated with branch vessel landmarks. Cardiac-induced deformation was computed from mid-diastole to end-systole.Pre-TEVAR, there were no significant cardiac-induced changes for aortic axial length or mean curvature. Post-TEVAR, the ascending aorta increased in axial length (2.7 ± 3.1%, P < 0.05) and decreased in mean curvature (0.38 ± 0.05 → 0.36 ± 0.05 cm−1, P < 0.05) from diastole to systole. From pre- to post-TEVAR, axial length change increased in the ascending aorta (P < 0.02), mean curvature decreased in the arch and stented aorta (P < 0.03), and peak curvature decreased in the stented aorta (P < 0.05).TEVAR for a range of indications not only causes direct geometric changes to the stented aorta but also results in dynamic changes to the ascending and stented aorta. In our cohort, endograft placement straightens the stented aorta and mutes cardiac-induced bending due to longitudinal stiffness. This is compensated by greater length and curvature changes from diastole to systole in the ascending aorta, relative to pre-TEVAR.

Aortic Isthmus Narrowing after Endovascular Repair of Acute Traumatic Aortic Transection.

PurposeThe traumatic transection is located in the normal sized aortic isthmus where the angle is curved. We found a reversal of upper and lower blood pressure differences among patients who underwent thoracic endovascular aortic repair (TEVAR) for transection of the thoracic aorta. We investigated the isthmus stenosis in patients who underwent TEVAR for aortic injury using computed tomography.Materials and MethodsSixteen patients who underwent TEVAR for transection were divided in two groups: the aortic narrowing (AN) group and the non-aortic narrowing (NAN) group. AN was defined as stent graft folding more than 5 mm at the isthmus confirmed by computed tomography. The length of aorta at isthmus, pseudoaneurysm, and angle of isthmus were measured.ResultsAN was noted in five patients (31.3%). The area index in the NAN group (2.16±0.35 cm2/m2) was larger than that in the AN group (1.74±0.77 cm2/m2). The size of the pseudoaneurysm in the NAN group (31.9±4.2 mm) was smaller than that in the AN group (37.4±7.5 mm). The distance from the subclavian artery in the NAN group (15.7±9.3 mm) was longer than that in the AN group (8.4±3.2 mm) but not statistically significant. The angle of the isthmus in the NAN group (131±6 degrees) was larger than that in the AN group (107±3 degrees), and this was the only statistically significant difference (P=0.002).ConclusionAN by stent graft folding should be considered when performing TE-VAR in aortic injury with an acute angle of the isthmus less than 110 degrees.

Is There Any Correlation Between Two and Three Dimensional Echocardiography in Ductal Dimensions with Angiography?

Background: The aim of this study was to determine if there is any correlation between patent ductus arteriosus (PDA) dimensions measured by two dimensional echocardiography (2DE) and three dimensional echocardiography (3DE) in comparison with angiographic data as the gold standard technique. Such correlation may help us to immediately detect ductal spasm and select the proper device according to echocardiographic assessments. Methods: In this comparative study, we successively selected 26 pediatric patients with isolated PDA, who referred for elective percutaneous PDA closure at Nemazee Hospital, affiliated to Shiraz University of Medical Sciences (SUMS) since January 2016 till March 2017. All patients underwent full 2DE and 3DE before device closure at the day of angiography (less than 5 hours before catheterization). We emphasized the dimension of pulmonic and aortic end diameter and length of PDA by these modalities and comparison of our data. Results: The study population had a mean age of 28.7 months and a mean weight of 10.67 Kg; the majority of our patients were female (84.6%). The difference in pulmonic end of PDA was not significant statistically by all modalities. The difference in aortic end of PDA was significant and there was no correlation between 2DE and 3DE with angiographic data. Comparison of data obtained from 2DE and 3DE revealed that the length of PDA in 2DE, 3DE angiography well correlated with each other. One case developed ductal spasm during angiography. Conclusions: The ductus pulmonic end and length dimensions measured by echocardiography and angiography well correlated with each other and were interchangeable. Such findings may be helpful during percutaneous transcatheter occlusion if any ductal spasm happens. Thus, we may recommend the use of a suitable device according to the maximum size of PDA that was measured either by echocardiography or angiographic studies.

Effect of emergency thoracic endovascular aortic repair in patients with acute traumatic thoracic aortic injury

Objective: To investigate the effect of emergency thoracic endovascular aortic repair (TEVAR) in patients with acute traumatic thoracic aortic injury. Method: From January 2014 to December 2016, a total of 35 patients with acute traumatic thoracic aortic injuries were treated with emergency TEVAR in our hospital, their clinical data were analyzed retrospectively in this study. Results: The patients were 42 (34, 55) years old,and there were 31 males.All cases were diagnosed by emergency aorta computed tomography angiography (CTA),and 5 cases were diagnosed as aortic transaction, 13 cases were diagnosed as aortic pseudoaneurysm, 7 cases were diagnosed as aortic dissection, and 10 cases were diagnosed as aortic intramural hematoma combined hemothorax.The concomitant injuries included cerebral contusion (3 cases, 8.6%), pulmonary contusion with rib fracture (31 cases, 88.5%), long bone fracture (7 cases, 22.5%), contusion of viscera or internal organs (3 cases, 8.6%).Emergency TEVAR were performed with vascular suture system preset under local anesthesia after diagnosis,and combined injury was treated in related departments.CTA was repeated after 1, 3 and 6 months and yearly thereafter. One patient died before transferring to catheter room,and 34 (97.1%) patients underwent TEVAR procedure successfully.Time from door to operating room was (88.6±26.6) minutes,and the procedure time was (52.0±9.4) minutes. A total of 69 Perclose Proglide vascular suture system were used,and 2 cases underwent surgical suture because of hematoma and pseudoaneurysm formation in femoral arteries.The involved length of thoracic aorta was (44.5±7.4)mm. A total of 46 stent-grafts were implanted, the length of stent-graft was (164.3±15.2)mm,and the proximal oversize rate was (22.3±8.6)%. The follow-up time was 24 (12,24) months, and there were no procedure related complication such as endoleak and paraplegia. Complete aortic remodeling was observed in 14 cases. Fully thrombolization at stent segments were observed in 7 cases. Fully thrombalization of pseudoaneurysms were observed in 13 cases. One patient complained mild left upper limb weakness due to left subclavian artery occlusion. Conclusion: Emergency TEVAR is safe and effective procedure for the treatment of patients with acute traumatic thoracic aortic injury.

Correction: Changes in aortic pulse wave velocity of four thoracic aortic stent grafts in an ex vivo porcine model.

[This corrects the article DOI: 10.1371/journal.pone.0186080.].

Abstract 106: Young Tgfbr2 G357W/+ Mice Have Decreased Expression of TGF-β Ligands and Receptors in the Proximal Aorta, Aortic Root Dilation, and Aortic Elongation

Introduction: Tgfbr2 G357W/+ mice have a loss-of-function Tgfbr2 allele ( G357W ) that is orthologous to an allele found in humans with Loeys-Dietz syndrome (LDS). Tgfbr2 G357W/+ mice have kyphosis, aortic dilation and elongation, and die suddenly from aortic rupture. Elevations of mRNA encoding TGF-β ligands in cultured vascular smooth muscle cells from Tgfbr2 G357W/+ mice and LDS patients—as well as increased expression of Tgfb1 and Col1a1 and elevation of both P-Smad2 and P-ERK1/2 in aortic roots of older (24-36-week) Tgfbr2 G357W/+ mice—suggest that paradoxically increased TGF-β signaling might be responsible for aortic pathology in LDS. Hypothesis: We hypothesized that downregulation of TGF-β signaling components accompanies the development of aortic pathology in young Tgfbr2 G357W/+ mice. Methods: We performed anatomic and gene-expression studies on 8- and 12-wk-old Tgfbr2 G357W/+ mice and wild type (WT) littermates. For anatomic studies, mice were perfusion-fixed with formalin, and aortic length was measured in situ. Aortic roots as well as ascending (ASA), descending thoracic (DTA) and abdominal aortas (AA) were then embedded in OCT. Frozen sections were stained with H &amp; E. External and internal elastic lamina lengths, aortic wall thickness and medial areas were measured. For gene expression studies, mice were saline-perfused, and the aortic root, ASA, and arch were snap frozen en bloc. RNA was extracted and TGF-β ligand and receptor mRNA were measured. Results: LDS mice (12 wk old; n = 7-9 vs 12 WT) had elongated ASA, arch, and DTA (~20%; P≤0.02), their aortic roots were dilated (20%; P&lt;0.001), and their DTA wall thickness and medial areas were decreased (15%; P&lt;0.01). No aortic wall hematomas were observed, and Prussian Blue staining was absent in aortic sections. mRNA encoding Tgfb1 , Tgfb2, Tgfbr1, Tgfbr3, Serpine1 , and LoxL1 were decreased in LDS mouse aortas (20-34%; P&lt;0.05 for all; n=9-10). LDS mice (8 wk old; n = 10 vs 12 WT) had only borderline decreased aortic Tgfbr1 mRNA. Conclusions: In Tgfbr2 G357W/+ mice, development of aortic pathology is accompanied by decreased expression of several TGF-β signaling pathway components. These data suggest that the G357W loss-of-function allele causes aortopathy via an early reduction of aortic TGF-β signaling.

Value of risk scores in the decision to palliate patients with ruptured abdominal aortic aneurysm.

BackgroundThe aim of this study was to develop a 48‐h mortality risk score, which included morphology data, for patients with ruptured abdominal aortic aneurysm presenting to an emergency department, and to assess its predictive accuracy and clinical effectiveness in triaging patients to immediate aneurysm repair, transfer or palliative care.MethodsData from patients in the IMPROVE (Immediate Management of the Patient With Ruptured Aneurysm: Open Versus Endovascular Repair) randomized trial were used to develop the risk score. Variables considered included age, sex, haemodynamic markers and aortic morphology. Backwards selection was used to identify relevant predictors. Predictive performance was assessed using calibration plots and the C‐statistic. Validation of the newly developed and other previously published scores was conducted in four external populations. The net benefit of treating patients based on a risk threshold compared with treating none was quantified.ResultsData from 536 patients in the IMPROVE trial were included. The final variables retained were age, sex, haemoglobin level, serum creatinine level, systolic BP, aortic neck length and angle, and acute myocardial ischaemia. The discrimination of the score for 48‐h mortality in the IMPROVE data was reasonable (C‐statistic 0·710, 95 per cent c.i. 0·659 to 0·760), but varied in external populations (from 0·652 to 0·761). The new score outperformed other published risk scores in some, but not all, populations. An 8 (95 per cent c.i. 5 to 11) per cent improvement in the C‐statistic was estimated compared with using age alone.ConclusionThe assessed risk scores did not have sufficient accuracy to enable potentially life‐saving decisions to be made regarding intervention. Focus should therefore shift to offering repair to more patients and reducing non‐intervention rates, while respecting the wishes of the patient and family.

Imaging Insights on the Aorta in Aging.

The aorta has 2 main functions, conduit and cushion, and is designed to transmit blood to the periphery and buffer pulsatile stress from ventricular contraction. In the interaction between the structural and functional changes of the aorta, aging and disease processes impact on aortic material properties and hemodynamics. For a comprehensive assessment of changes in aortic structure and function associated with aging and disease, noninvasive cardiovascular imaging techniques, especially magnetic resonance imaging, have recently been developed. Magnetic resonance imaging allows for direct and accurate measurement of different aortic characteristics including structural measures such as aortic area or volume, aortic length, curvature, and aortic wall thickness and functional measures such as aortic strain, distensibility, and pulse wave velocity. Excellent reproducibility of magnetic resonance imaging methods allows us to assess the response of the whole aorta to both pharmacological and nonpharmacological therapies. Aortic flow and functional assessment could be added to clinical routine cardiac magnetic resonance as a comprehensive imaging modality primarily performed for the noninvasive evaluation of left ventricular function, left ventricular load, and vascular/ventricular coupling. New techniques such as 4-dimensional flow could provide and further elucidate the combined age-related effects of altered aortic geometry and function. This following review will describe the pathophysiological aspects of the aorta and the ability, value, and prospects of cardiovascular imaging, especially magnetic resonance imaging, to study age-related changes in aortic structure and function and assess the relationship between these alterations and cardiovascular disease.