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International Journal For Numerical... Mar 2022It is important to obtain accurate boundary conditions (BCs) in hemodynamic simulations. This article aimed to improve the accuracy of BCs in computational fluid...
It is important to obtain accurate boundary conditions (BCs) in hemodynamic simulations. This article aimed to improve the accuracy of BCs in computational fluid dynamics (CFD) simulation and analyze the differences in hemodynamics between healthy volunteers and patients with visceral arterial stenosis (VAS). The geometric models of seven cases were reconstructed using the magnetic resonance angiogram (MRA) or computed tomography angiogram (CTA) imaging data. The physiological flow waveforms obtained from 2D Phase Contrast Magnetic Resonance Imaging (PCMRI) were imposed on the aortic inlet and the visceral arteries' outlets. The individualized RCR values of the three-element Windkessel model were imposed on the aortic outlet. CFD simulations were run in the open-source software: svSolver. Two specific time points were selected to compare the hemodynamics of healthy volunteers and patients with VAS. The results suggested that blood in the stenotic visceral arteries flowed at high speed throughout the cardiac cycle. The low pressure is distributed at stenotic lesions. The wall shear stress (WSS) reached 4 Pa near stenotic locations. The low time average wall shear stress (TAWSS), high oscillatory shear index (OSI), and high relative residence time (RRT) concentrated in the abdominal aorta. Besides, the ratios of the areas with low TAWSS, high OSI, and high RRT to the computational domain were higher in patients with VAS than which in the healthy volunteers. The individualized BCs were used for hemodynamic simulations and results suggest that patients with stenosis have a higher risk of blood retention and atherosclerosis formation in the abdominal aorta.
Topics: Aorta, Abdominal; Blood Flow Velocity; Computer Simulation; Constriction, Pathologic; Hemodynamics; Humans; Magnetic Resonance Imaging; Models, Cardiovascular; Stress, Mechanical
PubMed: 34967124
DOI: 10.1002/cnm.3569 -
Journal of Vascular Surgery Jul 2023The left retroperitoneal approach to the aorta is a well-established technique for aortic exposure. The right retroperitoneal approach to the aorta is performed less... (Review)
Review
OBJECTIVE
The left retroperitoneal approach to the aorta is a well-established technique for aortic exposure. The right retroperitoneal approach to the aorta is performed less commonly, and the outcomes remain unknown. This study aimed to evaluate the outcomes of right retroperitoneal aortic-based procedures and to determine its utility in aortic reconstruction when faced with hostile anatomy or infection in the abdomen or left flank.
METHODS
A retrospective query of a vascular surgery database from a tertiary referral center was performed for all retroperitoneal aortic procedures. Individual patient charts were reviewed, and data were collected. Demographics, indications, intraoperative details, and outcomes were tabulated.
RESULTS
From 1984 through 2020, there have been 7454 open aortic procedures; 6076 were retroperitoneal-based, and 219 of which were performed from the right retroperitoneal approach (Rrp). Aneurysmal disease was the most common indication (48.9%), and graft occlusion was the most common postoperative complication (11.4%). The average aneurysm size was 5.5 cm, and the most common reconstruction was with a bifurcated graft (77.6%). Average intraoperative blood loss was 923.8 mL (range, 50-6800 mL; median, 600 mL). Perioperative complications occurred in 56 patients (25.6%) for a total of 70 complications. Perioperative mortality occurred in two patients (0.91%). The 219 patients treated with Rrp required 66 subsequent procedures in 31 patients. These included 29 extra-anatomic bypasses, 19 thrombectomies/embolectomies, 10 bypass revisions, 5 infected graft excisions, and 3 aneurysm revisions. Eight Rrp eventually underwent a left retroperitoneal approach for aortic reconstruction. Fourteen patients with a left-sided aortic procedure required a Rrp.
CONCLUSIONS
The right retroperitoneal approach to the aorta is a useful technique in the setting of prior surgery, anatomic abnormality, or infection that complicates the use of other more frequently employed approaches. This review demonstrates comparable outcomes and the technical feasibility of this approach. The right retroperitoneal approach to aortic surgery should be considered a viable alternative to left retroperitoneal and transperitoneal access in patients with complex anatomy or prohibitive pathology for more traditional exposure.
Topics: Humans; Aorta, Abdominal; Retrospective Studies; Retroperitoneal Space; Abdomen; Vascular Surgical Procedures; Aortic Aneurysm, Abdominal
PubMed: 36889607
DOI: 10.1016/j.jvs.2023.02.013 -
Journal of Neonatal-perinatal Medicine 2022Aortic thrombosis in neonates is a rare phenomenon, and in most cases iatrogenic. An early recognition of the clinical features and an immediate intervention can offer a...
BACKGROUND
Aortic thrombosis in neonates is a rare phenomenon, and in most cases iatrogenic. An early recognition of the clinical features and an immediate intervention can offer a better prognosis, and thus preventing morbidity such as limb amputation, and even mortality.
METHODS
We present two cases of full-term newborns with a thrombosis of the abdominal aorta hospitalized in the neonatal intensive care unit of Mohammed VI University Hospital in Marrakech in 2017 and 2019.
RESULTS
The two patients presented swelling and cyanotic lower limbs. Doppler ultrasound revealed a pathological lower limb blood flow as a result of a thrombosis of the abdominal aorta. Both patients underwent an anticoagulant therapy, the first one benefited from a surgical thrombectomy, he developed a reperfusion syndrome with alveolar hemorrhage, and passed away as a result of a cardiorespiratory arrest. However the second patient got amputated of the right foot, his clinical evolution was favorable with a good healing of the surgical wound without recurrence of any thrombosis.
CONCLUSION
Through those cases clinicians should be aware of the first clinical signs of this condition in order to offer a rapid and successful management.
Topics: Angiography; Aorta, Abdominal; Humans; Infant, Newborn; Lower Extremity; Male; Thrombectomy; Thrombosis; Treatment Outcome
PubMed: 33935114
DOI: 10.3233/NPM-200678 -
Brazilian Journal of Cardiovascular... Oct 2020We performed a review of the literature (until August 01, 2019) on the occasion of the first transcaval approach for transcatheter aortic valve implantation in our... (Review)
Review
We performed a review of the literature (until August 01, 2019) on the occasion of the first transcaval approach for transcatheter aortic valve implantation in our hospital. This review focuses mainly on the indications of this alternative access route to the aorta. It may be useful for vascular surgeons in selected cases, such as the treatment of endoleaks after endovascular aneurysm repair and thoracic endovascular aneurysm repair. We describe historical aspects of transcaval access to the aorta, experimental studies, available case series and outcomes. Finally, we summarize the most significant technical aspects of this little-known access.
Topics: Aorta, Abdominal; Aortic Aneurysm, Abdominal; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Endovascular Procedures; Humans; Male; Stents; Surgeons; Treatment Outcome
PubMed: 33118744
DOI: 10.21470/1678-9741-2019-0240 -
Kyobu Geka. the Japanese Journal of... Sep 2023Although mortality and complication rates of cardiovascular surgery have been reduced, shaggy aorta, which is defined as an extensive severe atherosclerosis of the...
Although mortality and complication rates of cardiovascular surgery have been reduced, shaggy aorta, which is defined as an extensive severe atherosclerosis of the thoracic and abdominal aorta, is considered a risk factor for perioperative mortality and complications. The shaggy aorta often leads a poor prognosis, and a very high hospital mortality rate when embolization occurs in multiple organs. Therefore, it is important to prevent embolism through detailed evaluation of the disease with preoperative contrast-enhanced computed tomography (CT) scan and intraoperative transesophageal echocardiogram, appropriate individualized treatment decisions, and careful surgical manipulation.
Topics: Humans; Atherosclerosis; Aorta, Abdominal; Embolism; Tomography, X-Ray Computed; Risk Factors; Aorta, Thoracic; Aortic Diseases
PubMed: 38056835
DOI: No ID Found -
Annals of Vascular Surgery Jul 2021Penetrating cardiac injury (PCI) secondary to a gunshot wound presents with several complications and a mortality rate of 94% before reaching the hospital. Current...
Penetrating cardiac injury (PCI) secondary to a gunshot wound presents with several complications and a mortality rate of 94% before reaching the hospital. Current literature search reveals that embolism of bullet fragments after gunshot wounds are exceptionally rare. Additionally, no reported case was found regarding bullet embolism following left atrium penetration at the time of this case report. This case describes a 34-year-old male who presented to a level I trauma center after sustaining a gunshot wound to the posterior torso. Imaging demonstrated several fragments in the mid-thoracic region in addition to the primary bullet fragment located within the aorta at the bifurcation of the iliac arteries likely due to left atrial penetration and subsequent embolization.
Topics: Adult; Aorta, Abdominal; Aortography; Computed Tomography Angiography; Foreign-Body Migration; Heart Injuries; Humans; Male; Treatment Outcome; Wounds, Gunshot
PubMed: 33836233
DOI: 10.1016/j.avsg.2021.02.028 -
Biomolecules Mar 2022Abdominal aortic aneurysm (AAA), defined as a focal dilation of the abdominal aorta beyond 50% of its normal diameter, is a common and potentially life-threatening... (Review)
Review
Abdominal aortic aneurysm (AAA), defined as a focal dilation of the abdominal aorta beyond 50% of its normal diameter, is a common and potentially life-threatening vascular disease. The molecular and cellular mechanisms underlying AAA pathogenesis remain unclear. Healthy endothelial cells (ECs) play a critical role in maintaining vascular homeostasis by regulating vascular tone and maintaining an anti-inflammatory, anti-thrombotic local environment. Increasing evidence indicates that endothelial dysfunction is an early pathologic event in AAA formation, contributing to both oxidative stress and inflammation in the degenerating arterial wall. Recent studies utilizing single-cell RNA sequencing revealed heterogeneous EC sub-populations, as determined by their transcriptional profiles, in aortic aneurysm tissue. This review summarizes recent findings, including clinical evidence of endothelial dysfunction in AAA, the impact of biomechanical stress on EC in AAA, the role of endothelial nitric oxide synthase (eNOS) uncoupling in AAA, and EC heterogeneity in AAA. These studies help to improve our understanding of AAA pathogenesis and ultimately may lead to the generation of EC-targeted therapeutics to treat or prevent this deadly disease.
Topics: Aorta, Abdominal; Aortic Aneurysm, Abdominal; Dilatation, Pathologic; Endothelial Cells; Humans; Oxidative Stress
PubMed: 35454098
DOI: 10.3390/biom12040509 -
Research in Veterinary Science Jun 2023Aortic remodeling is the consequence of untreated systemic hypertension along with aortic dilatation as a marker for target organ damage in human literature. Therefore,...
Aortic remodeling is the consequence of untreated systemic hypertension along with aortic dilatation as a marker for target organ damage in human literature. Therefore, the present study was planned to detect the changes in aorta at the level of aortic root via echocardiography, thoracic descending aorta via radiography and abdominal aorta via ultrasonography in healthy (n = 46), diseased normotensive (n = 20) and systemically hypertensive dogs (n = 60). The aortic root dimensions were measured at the level of aortic annulus, sinus of valsalva, sino-tubular junction and proximal ascending aorta via left ventricular outflow tract view of echocardiography. The thoracic descending aorta was subjectively assessed for any disparity in size and shape of aorta via lateral and dorso-ventral view of chest radiography. The abdominal aorta was assessed via left and right paralumbar window for calculating the aortic elasticity along with aortic and caudal venacaval dimensions to calculate the aortic-caval ratio. The aortic root measurements were dilated (p < 0.001) in systemically hypertensive dogs with a positive correlation (p < 0.001) with systolic blood pressure (BP). Thoracic descending aorta was also (p < 0.05) altered in the size and shape (undulation) of systemically hypertensive dogs. Abdominal aorta was markedly stiffened with reduced elasticity (p < 0.05) along with dilatation (p < 0.01) in hypertensive dogs. Also, there was a positive correlation (p < 0.001) of aortic diameters and aortic-caval ratio and negative correlation (p < 0.001) of aortic elasticity with systolic BP. Therefore, it was concluded that aorta could be considered as an important target organ damage of systemic hypertension in dogs.
Topics: Humans; Dogs; Animals; Aorta, Abdominal; Hypertension; Aorta, Thoracic; Echocardiography; Ultrasonography; Dog Diseases
PubMed: 37141684
DOI: 10.1016/j.rvsc.2023.04.017 -
International Journal of Cardiology Jun 2024Surgery for Stanford type A aortic dissection (TAAD) is associated with an increased risk of late aortic reoperations due to degeneration of the dissected aorta.
BACKGROUND
Surgery for Stanford type A aortic dissection (TAAD) is associated with an increased risk of late aortic reoperations due to degeneration of the dissected aorta.
METHODS
The subjects of this analysis were 990 TAAD patients who survived surgery for acute TAAD and had complete data on the diameter and dissection status of all aortic segments.
RESULTS
After a mean follow-up of 4.2 ± 3.6 years, 60 patients underwent 85 distal aortic reoperations. Ten-year cumulative incidence of distal aortic reoperation was 9.6%. Multivariable competing risk analysis showed that the maximum preoperative diameter of the abdominal aorta (SHR 1.041, 95%CI 1.008-1.075), abdominal aorta dissection (SHR 2.133, 95%CI 1.156-3.937) and genetic syndromes (SHR 2.840, 95%CI 1.001-8.060) were independent predictors of distal aortic reoperation. Patients with a maximum diameter of the abdominal aorta >30 mm and/or abdominal aortic dissection had a cumulative incidence of 10-year distal aortic reoperation of 12.0% compared to 5.7% in those without these risk factors (adjusted SHR 2.076, 95%CI 1.062-4.060).
CONCLUSION
TAAD patients with genetic syndromes, and increased size and dissection of the abdominal aorta have an increased the risk of distal aortic reoperations. A policy of extensive surgical or hybrid primary aortic repair, completion endovascular procedures for aortic remodeling and tight surveillance may be justified in these patients.
TRIAL REGISTRATION
ClinicalTrials.gov Identifier: NCT04831073.
Topics: Humans; Aorta, Abdominal; Aortic Aneurysm; Reoperation; Blood Vessel Prosthesis Implantation; Aortic Dissection; Risk Factors; Aortic Aneurysm, Thoracic; Treatment Outcome; Retrospective Studies; Azides; Deoxyglucose
PubMed: 38458387
DOI: 10.1016/j.ijcard.2024.131938 -
Computer Methods in Biomechanics and... Nov 2021The flow velocity of visceral arteries was measured by 2D PCMRI to produce the patient-specific flow BC imposed on the outlets of visceral arteries in CFD simulation....
PURPOSE
The flow velocity of visceral arteries was measured by 2D PCMRI to produce the patient-specific flow BC imposed on the outlets of visceral arteries in CFD simulation. This modified method aimed to improve the CFD accuracy in the abdominal aorta and visceral arteries.
METHODS
A volunteer underwent non-contrast-enhanced MRA to scan the abdominal aorta and visceral arteries, and 2D PCMRI to obtain the flow velocity of the aforementioned vessels. The three-dimensional geometric model was reconstructed using the MRI scan data of the abdominal aorta and visceral arteries. The flow waveforms measured by 2D PCMRI were processed and then imposed on the aortic inlet and the outlets of all visceral arteries as the flow BC. The RCR parameters of the three elements Windkessel model were modulated and imposed on the aortic outlet. CFD simulation was run in the open-source software: svSolver. The same volunteer underwent 4D flow MRI to compare the flow field with those extracted from CFD results.
RESULTS
Four specific time points in a cardiac cycle and three cross-sectional planes of aorta were selected to analyze the flow field, pressure and wall shear stress (WSS) from CFD. The flow waveforms and streamlines of CFD agreed with those of 4D flow MRI. The pressure waveforms, pressure distribution and WSS distribution from CFD conformed with the physiological condition of human body.
CONCLUSION
These results suggest this modified CFD method may yield reasonable flow field, pressure and WSS in the abdominal aorta and visceral arteries.
Topics: Aorta, Abdominal; Blood Flow Velocity; Computer Simulation; Cross-Sectional Studies; Hemodynamics; Humans; Hydrodynamics; Models, Cardiovascular
PubMed: 34569360
DOI: 10.1080/10255842.2021.1912742