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Computer Methods and Programs in... Oct 2023The blood pressure and flow waveforms carry valuable information about the condition of the cardiovascular system and a patient's health. Waveform analysis in health and...
BACKGROUND AND OBJECTIVE
The blood pressure and flow waveforms carry valuable information about the condition of the cardiovascular system and a patient's health. Waveform analysis in health and pathological conditions can be performed in the time or frequency domains; the information to be emphasised defines the use of either domain. However, physicians are more familiar with the time domain, and the changes in the waveforms due to cardiovascular diseases and ageing are better characterised in such domain. On the other hand, the analysis of the vascular and geometrical variables determining the signatures in the frequency response of local vascular anomalies, such as aneurysms and stenoses, has not been thoroughly explored. This paper aims to characterise the signatures of obstructions (stenoses) and expansions (aneurysms) in the frequency response of tapered arteries.
METHODS
The first step in our methodology was to incorporate the viscous response of the arterial wall into a one-dimensional elastic formulation that solves the governing equations in the frequency domain. As a second step, we imposed a volumetric flow excitation in arteries simulating the aorta with increasing geometry complexity: from straight to tapered arteries with local expansions or obstructions; and we assessed the frequency response.
RESULTS
We found that the obstructions and expansions cause characteristic signatures in an artery's frequency response that are distinguishable from a health condition. The signatures of obstruction and expansions differ; the obstructions increase the magnitude of fundamental frequency and work as a close boundary condition. On the other hand, the expansions diminish the fundamental frequency and work as an open boundary condition. Furthermore, such signatures correlate to the distance between the artery's inlet and the anomaly's starting point and have the potential to pinpoint abnormalities non-invasively.
CONCLUSIONS
We found that the obstructions and expansions cause characteristic signatures in an artery's frequency response that have the potential to detect and follow up on the development of vascular abnormalities. For the latter purpose, constant monitoring may be required; despite this not being a common clinical practice, the new wearable technology offers the possibility of continuous monitoring of biophysical markers such as the pressure waveform.
Topics: Constriction, Pathologic; Vascular Diseases; Humans; Arteries
PubMed: 37336151
DOI: 10.1016/j.cmpb.2023.107628 -
Abdominal Radiology (New York) Jun 2021Non-occlusive hepatic artery hypoperfusion syndrome (NHAHS), in other words, splenic steal, is a rare disorder that can arise following liver transplantation. After... (Review)
Review
Non-occlusive hepatic artery hypoperfusion syndrome (NHAHS), in other words, splenic steal, is a rare disorder that can arise following liver transplantation. After liver transplantation, its frequency has been defined as between 0.6 and 10.1%. The diversion of flow from hepatic to splenic arteries results in low perfused hepatic artery which causes elevated liver enzymes, hyperbilirubinemia, and graft dysfunction. This may result from a high resistance in the hepatic arteries, enlarged splenic arteries, a limited hepatic arterial flow due to high portal flow, or a discordance of the graft size and hepatic arterial flow. There may be a need for some prophylactic and/or posttransplant treatment procedures. We aimed to describe pre and post-treatment imaging findings of NHAHS.
Topics: Hepatic Artery; Humans; Ischemia; Liver Diseases; Liver Transplantation; Splenic Artery
PubMed: 33159211
DOI: 10.1007/s00261-020-02850-7 -
International Journal of Molecular... Jul 2019Arterial stiffness is an age-related disorder. In the medial layer of arteries, mechanical fracture due to fatigue failure for the pulsatile wall strain causes medial... (Review)
Review
Arterial stiffness is an age-related disorder. In the medial layer of arteries, mechanical fracture due to fatigue failure for the pulsatile wall strain causes medial degeneration vascular remodeling. The alteration of extracellular matrix composition and arterial geometry result in structural arterial stiffness. Calcium deposition and other factors such as advanced glycation end product-mediated collagen cross-linking aggravate the structural arterial stiffness. On the other hand, endothelial dysfunction is a cause of arterial stiffness. The biological molecular mechanisms relating to aging are known to involve the progression of arterial stiffness. Arterial stiffness further applies stress on large arteries and also microcirculation. Therefore, it is closely related to adverse outcomes in cardiovascular and cerebrovascular system. Cardio-ankle vascular index (CAVI) is a promising diagnostic tool for evaluating arterial stiffness. The principle is based on stiffness parameter β, which is an index intended to assess the distensibility of carotid artery. Stiffness parameter β is a two-dimensional technique obtained from changes of arterial diameter by pulse in one section. CAVI applied the stiffness parameter β to all of the arterial segments between heart and ankle using pulse wave velocity. CAVI has been commercially available for a decade and the clinical data of its effectiveness has accumulated. The characteristics of CAVI differ from other physiological tests of arterial stiffness due to the independency from blood pressure at the time of examination. This review describes the pathophysiology of arterial stiffness and CAVI. Molecular mechanisms will also be covered.
Topics: Algorithms; Arteries; Biomarkers; Cardio Ankle Vascular Index; Cardiovascular Diseases; Cardiovascular Physiological Phenomena; Female; Humans; Male; Models, Cardiovascular; Prognosis; Vascular Stiffness
PubMed: 31357449
DOI: 10.3390/ijms20153664 -
The Journal of Physiology Apr 2016Advancing age may be the most potent independent predictor of future cardiovascular events, a relationship that is not fully explained by time-related changes in... (Review)
Review
Advancing age may be the most potent independent predictor of future cardiovascular events, a relationship that is not fully explained by time-related changes in traditional cardiovascular risk factors. Since some arteries exhibit differential susceptibility to atherosclerosis, generalisations regarding the impact of ageing in humans may be overly simplistic, whereas in vivo assessment of arterial function and health provide direct insight. Coronary and peripheral (conduit, resistance and skin) arteries demonstrate a gradual, age-related impairment in vascular function that is likely to be related to a reduction in endothelium-derived nitric oxide bioavailability and/or increased production of vasoconstrictors (e.g. endothelin-1). Increased exposure and impaired ability for defence mechanisms to resist oxidative stress and inflammation, but also cellular senescence processes, may contribute to age-related changes in vascular function and health. Arteries also undergo structural changes as they age. Gradual thickening of the arterial wall, changes in wall content (i.e. less elastin, advanced glycation end-products) and increase in conduit artery diameter are observed with older age and occur similarly in central and peripheral arteries. These changes in structure have important interactive effects on artery function, with increases in small and large arterial stiffness representing a characteristic change with older age. Importantly, direct measures of arterial function and structure predict future cardiovascular events, independent of age or other cardiovascular risk factors. Taken together, and given the differential susceptibility of arteries to atherosclerosis in humans, direct measurement of arterial function and health may help to distinguish between biological and chronological age-related change in arterial health in humans.
Topics: Aging; Animals; Arteries; Atherosclerosis; Hemodynamics; Humans
PubMed: 26140618
DOI: 10.1113/JP270597 -
Aesthetic Surgery Journal Apr 2022A consensus on facial artery anatomy has not been established due to the discrepancies in previous studies.
BACKGROUND
A consensus on facial artery anatomy has not been established due to the discrepancies in previous studies.
OBJECTIVES
The authors sought to assess the branches, course, and location of the facial artery in Asians by utilizing computed tomographic angiography.
METHODS
The computed tomographic angiography images of 300 facial arteries from 150 Asian patients were evaluated. The FA was classified as follows: type 1, facial artery terminates superior labial or inferior labial artery; type 2, facial artery terminates lateral nasal or inferior alar artery; type 3, facial artery terminates medial canthal artery; or type 4, facial artery is divided into duplex branches with dominant medial canthal artery laterally. The relationship between nasolabial fold and FA was evaluated, and the distances from anatomical landmarks to FA were measured to position the course.
RESULTS
Seventy (23.3%), 163 (54.3%), 49 (16.3%), and the other 18 arteries (6.0%) were classified as type 1, 2, 3, and 4, respectively. A total 72.3% of facial arteries were located medially to the nasolabial fold, and only 14.7% of arteries were lateral to the nasolabial fold. The vertical distance between the facial artery and the inner canthus or the midpoint of the inferior orbital rim decreased from type 1 to type 4 facial artery (P < 0.0001). The 4 types did not significantly differ in distance between the mandibular angle (P = 0.1226) or oral commissure (P = 0.1030) and the facial artery at inferior of mandible.
CONCLUSIONS
Detailed findings of the facial artery will provide a valuable reference for filler injection in cosmetic procedures and flap design in reconstructive surgery.
Topics: Angiography; Arteries; Asian People; Humans; Mandible; Nasolabial Fold
PubMed: 34724046
DOI: 10.1093/asj/sjab380 -
Canadian Association of Radiologists... Feb 2022The purpose of this article is to review the embryology of the lower limb arterial anatomy along with common variants and their clinical relevance. (Review)
Review
OBJECTIVES
The purpose of this article is to review the embryology of the lower limb arterial anatomy along with common variants and their clinical relevance.
DESIGN
Embryologic variations of the lower limb arterial system may be explained by i.) persistence of primordial arterial segments, ii.) abnormal fusion, iii.) segmental hypoplasia/absence, or a combination of both. Persistent sciatic artery, corona mortis, and popliteal entrapment syndrome will also be discussed with associated symptoms, and potential complications.
CONCLUSION
Knowledge of these variations is essential for surgical and endovascular management as failure to recognize them can result in complications.
Topics: Arteries; Female; Humans; Lower Extremity; Male
PubMed: 33886403
DOI: 10.1177/08465371211003860 -
Arterial Tortuosity and Its Correlation with White Matter Hyperintensities in Acute Ischemic Stroke.Neural Plasticity 2022The association between arterial tortuosity and acute ischemic stroke (AIS) has been reported, but showing inconsistent results. We hypothesized that tortuosity of... (Clinical Trial)
Clinical Trial
INTRODUCTION
The association between arterial tortuosity and acute ischemic stroke (AIS) has been reported, but showing inconsistent results. We hypothesized that tortuosity of extra- and intracranial large arteries might be higher in AIS patients. Furthermore, we explored the correlation between artery tortuosity and white matter hyperintensity (WMH) severity in AIS patients.
METHODS
166 AIS patients identified as large artery atherosclerosis, and 83 control subjects were enrolled. All subjects received three-dimensional computed tomography angiography (CTA). Arterial tortuosity was evaluated using the tortuosity index. WMHs were evaluated using magnetic resonance imaging in all AIS patients.
RESULTS
AIS patients showed significantly increased arterial tortuosity index relative to controls, including left carotid artery (CA) ( = 0.001), right CA ( < 0.001), left common carotid artery (CCA) ( < 0.001), right CCA ( < 0.001), left internal carotid artery ( = 0.001), right internal carotid artery ( = 0.01), left extracranial internal carotid artery (EICA) ( < 0.001), right EICA ( = 0.01), and vertebral artery dominance (VAD) ( = 0.001). The tortuosity of all above arteries was associated with the presence of AIS. AIS patients with moderate or severe WMHs had a higher tortuosity index in left CA ( = 0.005), left CCA ( = 0.003), left EICA ( = 0.07), and VAD ( = 0.001). In addition, the tortuosity of left EICA and VAD was associated with WMH severity in AIS patients.
CONCLUSIONS
Increased extra- and intracranial large arteries tortuosity is associated with AIS. The tortuosity of left carotid artery system and vertebral artery may be the independent risk factors for WMH severity in AIS patients. . This trial is registered with NCT03122002 (http://www.clinicaltrials.gov).
Topics: Arteries; Carotid Artery, Internal; Humans; Ischemic Stroke; Joint Instability; Skin Diseases, Genetic; Vascular Malformations; White Matter
PubMed: 35369646
DOI: 10.1155/2022/4280410 -
Clinical Anatomy (New York, N.Y.) Sep 2018Variations of testicular vessels are more common than supposed. The testicular artery varies because of abnormal regression of the lateral mesonephric arteries in the... (Meta-Analysis)
Meta-Analysis Review
Variations of testicular vessels are more common than supposed. The testicular artery varies because of abnormal regression of the lateral mesonephric arteries in the fetus, whereas variations in the testicular vein are due to abnormalities in the involution of the intersubcardinal anastomosis. Such variations are usually found incidentally during surgical procedures around the renal pedicle and they often lead to complications. Several authors have attempted to classify them. However, these attempts have not been comprehensive. Therefore, the aim of this study is to provide a simple yet comprehensive classification of variations of the testicular vessels. The PubMed database was searched using keywords pertaining to the testicular vessels. The results were subjected to the Anatomical Quality Assessment (AQUA) tool analysis and were screened for appropriateness for inclusion in this study. The screening procedure yielded 31 original articles, 83 case reports, and 1 review article. Both testicular arterial and venous variations were more common on the left side (20.73% and 24.61%) than the right (12.69% and 18.4%, respectively). We classified the testicular arteries on the basis of their number (N), site of origin (O), and course (C). Similarly, the testicular veins were classified on the basis of their number (N) and site of drainage (D). The proposed classification facilitates identification, understanding, and reporting of variations of the testicular vessels by radiologists. It will also help surgeons to enhance the quality of their treatment. Clin. Anat. 31:854-869, 2018. © 2018 Wiley Periodicals, Inc.
Topics: Aorta, Abdominal; Arteries; General Surgery; Humans; Male; Testis; Veins
PubMed: 29737575
DOI: 10.1002/ca.23204 -
Current Medicinal Chemistry 2019Apolipoprotein B -containing lipoproteins include triglyceride-rich lipoproteins (chylomicrons and their remnants, and very low-density lipoproteins and their remnants)... (Review)
Review
Apolipoprotein B -containing lipoproteins include triglyceride-rich lipoproteins (chylomicrons and their remnants, and very low-density lipoproteins and their remnants) and cholesterol-rich low-density lipoprotein particles. Of these, lipoproteins having sizes below 70-80 nm may enter the arterial wall, where they accumulate and induce the formation of atherosclerotic lesions. The processes that lead to accumulation of lipoprotein-derived lipids in the arterial wall have been largely studied with a focus on the low-density lipoprotein particles. However, recent observational and genetic studies have discovered that the triglyceriderich lipoproteins and their remnants are linked with cardiovascular disease risk. In this review, we describe the potential mechanisms by which the triglyceride-rich remnant lipoproteins can contribute to the development of atherosclerotic lesions, and highlight the differences in the atherogenicity between low-density lipoproteins and the remnant lipoproteins.
Topics: Animals; Arteries; Coronary Artery Disease; Humans; Inflammation; Lipids; Lipoproteins; Triglycerides
PubMed: 29848270
DOI: 10.2174/0929867325666180530094819 -
Diagnostic and Interventional Imaging Jun 2015The availability of intra-arterial hepatic therapies (radio and/or chemo-embolisation, intra-arterial hepatic chemotherapy) has convinced radiologists to perfect their... (Review)
Review
The availability of intra-arterial hepatic therapies (radio and/or chemo-embolisation, intra-arterial hepatic chemotherapy) has convinced radiologists to perfect their knowledge of the anatomy of the liver arteries. These sometimes, complex procedures most often require selective arterial catheterization. Knowledge of the different arteries in the liver and the peripheral organs is therefore essential to optimize the procedure and avoid eventual complications. This paper aims to describe the anatomy of the liver arteries and the variants, applying it to angiography images, and to understand the implications of such variations in interventional radiological procedures.
Topics: Celiac Artery; Hepatic Artery; Humans; Liver; Radiography; Radiology, Interventional
PubMed: 24534562
DOI: 10.1016/j.diii.2013.12.001