Search results for: stenosed artery

Authors: Mohammed Abdulhameed, Sagir M. Abdullahi

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In this paper, based on the applications of nanoparticle, the blood flow along with nanoparticles through stenosed artery is studied. The blood is acted by periodic body acceleration, an oscillating pressure gradient and an external magnetic field. The mathematical formulation is based on Caputo-Fabrizio fractional derivative without singular kernel. The model of ordinary blood, corresponding to time-derivatives of integer order, is obtained as a limiting case. Analytical solutions of the blood velocity and temperature distribution are obtained by means of the Hankel and Laplace transforms. Effects of the order of Caputo-Fabrizio time-fractional derivatives and three different nanoparticles i.e. Fe3O4, TiO4 and Cu are studied. The results highlights that, models with fractional derivatives bring significant differences compared to the ordinary model. It is observed that the addition of Fe3O4 nanoparticle reduced the resistance impedance of the blood flow and temperature distribution through bell shape stenosed arteries as compared to TiO4 and Cu nanoparticles. On entering in the stenosed area, blood temperature increases slightly, but, increases considerably and reaches its maximum value in the stenosis throat. The shears stress has variation from a constant in the area without stenosis and higher in the layers located far to the longitudinal axis of the artery. This fact can be an important for some clinical applications in therapeutic procedures.

Keywords: nanoparticles, blood flow, stenosed artery, mathematical models

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Authors: Sreeparna Majee, G. C. Shit

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Unsteady blood flow has been numerically investigated through stenosed arteries to achieve an idea about the physiological blood flow pattern in diseased arteries. The blood is treated as Newtonian fluid and the arterial wall is considered to be rigid having deposition of plaque in its lumen. For direct numerical simulation, vorticity-stream function formulation has been adopted to solve the problem using implicit finite difference method by developing well known Peaceman-Rachford Alternating Direction Implicit (ADI) scheme. The effects of magnetic parameter and Reynolds number on velocity and wall shear stress are being studied and presented quantitatively over the entire arterial segment. The streamlines have been plotted to understand the flow pattern in the stenosed artery, which has significant alterations in the downstream of the stenosis in the presence of magnetic field. The results show that there are nominal changes in the flow pattern when magnetic field strength is enhanced upto 8T which can have remarkable usage to MRI machines.

Keywords: magnetohydrodynamics, blood flow, stenosis, energy dissipation

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Authors: Shashi Sharma, Uaday Singh, V. K. Katiyar

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Blood flow through a stenosed tube, which is of great interest to mechanical engineers as well as medical researchers. If stenosis exists in an artery, normal blood flow is disturbed. The deposition of fatty substances, cholesterol, cellular waste products in the inner lining of an artery results to plaque formation .The present study deals with a mathematical model for blood flow in constricted arteries. Blood is considered as a Newtonian, incompressible, unsteady and laminar fluid flowing in a cylindrical rigid tube along the axial direction. A time varying pressure gradient is applied in the axial direction. An analytical solution is obtained using the numerical inversion method for Laplace Transform for calculating the velocity profile of fluid as well as particles.

Keywords: blood flow, stenosis, Newtonian fluid, medical biology and genetics

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Authors: B. Prashantha, S. Anish

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The aim of the present study is to computationally evaluate the hemodynamic factors which affect the formation of atherosclerosis and plaque rupture in the human artery. An increase of atherosclerosis disease in the artery causes geometry changes, which results in hemodynamic changes such as flow separation, reattachment, and adhesion of new cells (chemotactic) in the artery. Hence, geometry plays an important role in the determining the nature of hemodynamic patterns. Influence of stenosis in the non-bifurcating artery, under pulsatile flow condition, has been studied on an idealized geometry. Analysis of flow through symmetric and asymmetric stenosis in the artery revealed the significance of oscillating shear index (OSI), flow separation, low WSS zones and secondary flow patterns on plaque formation. The observed characteristic of flow in the post-stenotic region highlight the importance of plaque eccentricity on the formation of secondary stenosis on the arterial wall.

Keywords: atherosclerotic plaque, oscillatory shear index, stenosis nature, wall shear stress

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Authors: M. A. Anwar, K. Iqbal, M. Razzaq

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Background and Objectives: This numerical study reflects the magnetic field's effect on the reduction of plaque formation due to stenosis in a stenosed bifurcated artery. The entire arterythe wall is assumed as linearly elastic, and blood flow is modeled as a Newtonian, viscous, steady, incompressible, laminar, biomagnetic fluid. Methods: An Arbitrary Lagrangian-Eulerian (ALE) technique is employed to formulate the hemodynamic flow in a bifurcated artery under the effect of the asymmetric magnetic field by two-way Fluid-structure interaction coupling. A stable P2P1 finite element pair is used to discretize thenonlinear system of partial differential equations. The resulting nonlinear system of algebraic equations is solved by the Newton Raphson method. Results: The numerical results for displacement, velocity magnitude, pressure, and wall shear stresses for Reynolds numbers, Re = 500, 1000, 1500, 2000, in the presence of magnetic fields are presented graphically. Conclusions: The numerical results show that the presence of the magnetic field influences the displacement and flows velocity magnitude considerably. The magnetic field reduces the flow separation, recirculation area adjacent to stenosis and gives rise to wall shear stress.

Keywords: bifurcation, elastic walls, finite element, wall shear stress,

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Authors: D. Srinivasacharya, G. Madhava Rao

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In this article, the pulsatile flow of blood flow in bifurcated artery with mild stenosis is investigated. Blood is treated to be a micropolar fluid with constant density. The arteries forming bifurcation are assumed to be symmetric about its axes and straight cylinders of restricted length. As the geometry of the stenosed bifurcated artery is irregular, it is changed to regular geometry utilizing the appropriate transformations. The numerical solutions, using the finite difference method, are computed for the flow rate, the shear stress, and the impedance. The influence of time, coupling number, half of the bifurcated angle and Womersley number on shear stress, flow rate and impedance (resistance to the flow) on both sides of the flow divider is shown graphically. It has been observed that the shear stress and flow rate are increasing with increase in the values of Womersley number and bifurcation angle on both sides of the apex. The shear stress is increasing along the inner wall and decreasing along the outer wall of the daughter artery with an increase in the value of coupling number. Further, it has been noticed that the shear stress, flow rate, and impedance are perturbed largely near to the apex in the parent artery due to the presence of backflow near the apex.

Keywords: micropolar fluid, bifurcated artery, stenosis, back flow, secondary flow, pulsatile flow, Womersley number

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Authors: S. M. Abdul Khader, Anurag Ayachit, Raghuvir Pai, K. A. Ahmed, V. R. K Rao, S. Ganesh Kamath

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The numerical simulation has made tremendous advances in investigating the blood flow phenomenon through elastic arteries. Such study can be useful in demonstrating the disease progression and haemodynamics of cardiovascular diseases such as atherosclerosis. In the present study, patient specific case diagnosed with partially stenosed complete right ICA and normal left carotid bifurcation without any atherosclerotic plaque formation is considered. 3D patient specific carotid bifurcation model is generated based on CT scan data using MIMICS-4.0 and numerical analysis is performed using FSI solver in ANSYS-14.5. The blood flow is assumed to be incompressible, homogenous and Newtonian, while the artery wall is assumed to be linearly elastic. The two-way sequentially-coupled transient FSI analysis is performed using FSI solver for three pulse cycles. The haemodynamic parameters such as flow pattern, Wall Shear Stress, pressure contours and arterial wall deformation are studied at the bifurcation and critical zones such as stenosis. The variation in flow behavior is studied throughout the pulse cycle. Also, the simulation results reveals that there is a considerable increase in the flow behavior in stenosed carotid in contrast to the normal carotid bifurcation system. The investigation also demonstrates the disturbed flow pattern especially at the bifurcation and stenosed zone elevating the haemodynamics, particularly during peak systole and later part of the pulse cycle. The results obtained agree well with the clinical observation and demonstrates the potential of patient specific numerical studies in prognosis of disease progression and plaque rupture.

Keywords: fluid-structure interaction, arterial stenosis, wall shear stress, carotid artery bifurcation

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Authors: Xi Gu, Guan Heng Yeoh, Victoria Timchenko

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In the current work, a three-dimensional geometry of a 75% stenosed blood vessel is analysed. Large eddy simulation (LES) with the help of a dynamic subgrid scale Smagorinsky model is applied to model the turbulent pulsatile flow. The geometry, the transmural pressure and the properties of the blood and the elastic boundary were based on clinical measurement data. For the flexible wall model, a thin solid region is constructed around the 75% stenosed blood vessel. The deformation of this solid region was modelled as a deforming boundary to reduce the computational cost of the solid model. Fluid-structure interaction is realised via a two-way coupling between the blood flow modelled via LES and the deforming vessel. The information of the flow pressure and the wall motion was exchanged continually during the cycle by an arbitrary lagrangian-eulerian method. The boundary condition of current time step depended on previous solutions. The fluctuation of the velocity in the post-stenotic region was analysed in the study. The axial velocity at normalised position Z=0.5 shows a negative value near the vessel wall. The displacement of the elastic boundary was concerned in this study. In particular, the wall displacement at the systole and the diastole were compared. The negative displacement at the stenosis indicates a collapse at the maximum velocity and the deceleration phase.

Keywords: Large Eddy Simulation, Fluid Structural Interaction, constricted artery, Computational Fluid Dynamics

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Authors: Raid Hommady, Waseem Al-Talalwah, Shorok Al Dorazi, Roger Soames

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The iliolumbar artery is a regular branch of posterior division of the internal iliac artery. The present study investigate 82 specimens to identify the origin of iliolumbar artery. The present study targets the sciatic nerve root supply from iliolumbar artery based on its origin and course. In present study, the ililumbar artery arose from the posterior division of internal iliac artery in 52.2%. In few cases, it arose from dorsomedial aspect of the internal iliac artery in 28.8%. In few cases, the iliolumbar artery arose from the dorsal aspects of the internal iliac artery as well as from the common and external iliac artery 1.7%. Also, the iliolumbar artery arose from the sciatic artery as well as from superior and inferior gluteal arteries in 5.1%. Conversely, it found to be congenital absent in 8.5%. Therefore, the posterior trunk of the internal iliac artery is the most common origin of the iliolumbar artery. With the origin variability of the iliolumbar artery, there is a vascular supply variability of the lumbosacral trunk and sacral root of sciatic nerve. The iliolumbar artery provides vascular supply for lumbosacral trunk 57.3% in whereas the sacral root in 5.1%. As a result, surgeons should pay attention to these variations to decrease iatrogenic fault.

Keywords: iliolumbar, sciatic artery, internal iliac, external iliac, posterior division

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Authors: Adel Yasky, Waseem Al-Talalwah, Shorok Al Dorazi, Roger Soames

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The internal pudendal artery is a standard branch of the anterior division of the internal iliac artery. The current study includes 41 cadavers to investigate the origin and branches of the internal pudendal artery and its clinical significances. The internal pudendal artery arose directly from the anterior division of the internal iliac artery in 48.3% while it arose indirectly in 48.5%. However, the internal pudendal artery arose from the posterior division of internal iliac artery in 1.6%. Moreover, it arose internal iliac artery bifurcation site in 1.6%. Further, the internal pudendal artery supplied the urinary bladder in 17.1%. Also, the internal pudendal artery supplied the rectum 33.5% respectively. It gave uterine and vaginal arteries in 9.4% and 7.8% respectively. Finally, it supplied the sciatic nerve via giving lateral sacral branch in 1.6%. Internists, surgeons and radiologists have to be aware of the variability to decrease iatrogenic injury. Therefore, unnecessary proximal ligation should be avoided at the site of indirect origin of the internal pudendal artery to prevent sciatic neuropathy. Further, intrapelvic bleeding as result of laceration of internal pudendal branches during hysterectomy, prostatectomy or proctectomy should be expected. Therefore, this study increases the awareness of surgeons leading to minimize iatrogenic faults,

Keywords: internal pudendal artery, inferior gluteal artery, superior gluteal artery, internal iliac artery, impotence, decreased libido

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Authors: Nawaf Al-Kharashi, Waseem Al-Talalwah, Shorok Al Dorazi, Roger Soames

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Superior gluteal artery is one of the largest branches of posterior division of the internal iliac artery. It passes between the lumbosacral and first sacral root to escape from the pelvic cavity through the grater sciatic foramen just above the piriformis. The current study includes 41 cadaver investigates the origin and branch of the superior gluteal artery and clarify the clinical significance. In present study, the superior gluteal artery arises from the posterior division of the internal iliac artery directly in 82.5% whereas it arises indirectly as from the sciatic artery in 15.9%. However, it is congenital absence in 1.6% which is compensated by sciatic artery. The sciatic nerve gains vascular supply from superior gluteal artery in two ways either during its course or giving lateral sacral artery in 27% and lumbar branches in 1.6%. It also supplies the adductors group and iliacus via giving obturator artery in 14.3% and in 1.6% respectively. The superior gluteal artery usually passes between lumbosacral trunk and first sacral root in 82.5% whereas it does not passes the sciatic roots as it arises behind them in 15.9%. With a variability of the superior gluteal artery origin, there is a variability of sciatic nerve roots supply. Further, the superior gluteal artery arising from sciatic artery behind the sciatic roots carries a high risk of intra-pelvic bleeding in case of posterior pelvic fracture. Prolonged ligation of the superior gluteal artery which gives lateral sacral artery may result in sciatic neuropathy. Therefore, surgeons have to be aware of the superior gluteal artery variation in origin, course and branches to reduce the iatrogenic faults.

Keywords: internal pudendal artery, inferior gluteal artery, superior gluteal artery, internal iliac artery. sciatic neuropathy, sciatic nerve

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Authors: Ashwin Rai, Rajalakshmi Rai, Rajanigandha Vadgoankar

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Lingual artery is the chief artery of the tongue and the neighboring structures pertaining to the oral cavity. At the carotid triangle, this artery arises from the external carotid artery opposite to the tip of greater cornua of hyoid bone, undergoes a tortuous course with its first part being crossed by the hypoglossal nerve and runs beneath the digastric muscle. Then it continues to supply the tongue as the deep lingual artery. The aim of this study is to draw surgeon's attention to the course of lingual artery in this area since it can be accidentally lesioned causing an extensive hemorrhage in certain surgical or dental procedures. The study was conducted on 44 formalin fixed head and neck specimens focusing on the anatomic relations of lingual artery. In this study, we found that the lingual artery is located inferior to the digastric muscle and the hypoglossal nerve contradictory to the classical description. This data would be useful during ligation of lingual artery to avoid injury to the hypoglossal nerve in surgeries related to the anterior triangle of neck.

Keywords: anterior triangle, digastric muscle, hypoglossal nerve, lingual artery

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Authors: M. Y. Lee, S. H. Park, S. M. Yu, H. S. Jo, C. G. Song

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Photoacoustic imaging is the imaging technology that combines the optical imaging with ultrasound. It also provides the high contrast and resolution due to optical and ultrasound imaging, respectively. For these reasons, many studies take experiment in order to apply this method for many diagnoses. We developed the real-time photoacoustic tomography (PAT) system using linear-ultrasound transducer. In this study, we conduct the experiment using swine and detect the blood of carotid artery and femoral artery. We measured the blood of femoral and carotid artery of swine and reconstructed the image using 950nm due to the HbO₂ absorption coefficient. The photoacoustic image is overlaid with ultrasound image in order to match the position. In blood of artery, major composition of blood is HbO₂. In this result, we can measure the blood of artery.

Keywords: photoacoustic tomography, swine artery, carotid artery, femoral artery

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Authors: Ramya Rathan, Miral N. F. Salama

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The variations in the arteries have been drawing attention of anatomists for a long time because of their clinical significance. The brachial artery is the principal artery of the arm which is the continuation of the axillary artery from the lower border of the Teres Major. It terminates into the radial and ulnar arteries below the elbow joint at the neck radius. The present study aims at exploring the clinical significance of the high termination of the brachial artery. During the routine cadaveric dissection of the arm, for the undergraduate students of medicine at our university, we observed a high bifurcation of the radial and the ulnar artery at the midshaft of the humerus. The median nerve was seen passing between these two junctions. Further, the course and the relations of this artery were studied. The accurate knowledge regarding these kinds of variation in the blood vessels is mandatory for planning of designing. General physicians, surgeons and radiologists should keep in mind the variations in the branching pattern of the arteries in their daily medical, diagnostic and therapeutic procedures to avoid complications in diagnostic and surgical procedures.

Keywords: brachial artery, high termination, radial artery, ulnar artery

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Authors: Waseem Al Talalwah, Shorok Al Dorazi, Roger Soames

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The inferior gluteal artery is a prominent branch of the anterior trunk of internal iliac artery. It escapes from the pelvic cavity through the greater sciatic foramen below the lower edge of piriformis. In gluteal region, it provides several muscular branches to gluteal maximus and articular branch to hip joint. Further, it provides sciatic branch to sciatic nerve. Current study investigates the origin of the inferior gluteal artery of 41 cadavers in Centre for Anatomy and Human Identification, University of Dundee, UK. It arose from the anterior trunk in 37.5% independently and 45.7% dependently as with the internal pudendal artery. Therefore, it arose from the anterior trunk in 83.2%. However, it found to be as a branch of the posterior trunk of internal iliac artery in 7.7% which is either a direct branch in 6.2% as or indirect branch in 1.5%. Beside the inferior gluteal artery arose with internal pudendal artery as from GPT of anterior division in 45.7%, it arose from the GPT arising from the internal iliac artery bifurcation site in 1.5%. Further, the inferior gluteal artery arose from the trunk with internal pudendal and obturator arteries in 1.5% referred as obturatogluteopudendal trunk. Occasionally, it arose from the sciatic artery in 1.5%. In few cases, the inferior gluteal artery found to be congenital absence in 4.6% which is compensated by the persistent sciatic artery. Therefore, radiologists have to aware of the origin variability of the inferior gluteal artery to alert surgeons. Knowing the origin of the inferior gluteal artery may help the surgeons to avoid iatrogenic sciatic neuropathy in pelvic procedures such as removing prostate or of uterine fibroid. Further, it may also prevent avascular necrosis of femur neck as well as gluteal claudication.

Keywords: inferior gluteal artery, internal iliac artery, sciatic neuropathy, gluteal claudication

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Authors: Anasuya Ghosh, Subhramoy Chaudhury

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During routine cadaveric dissection at gross anatomy lab of our institution, a radial artery was found with unusual origin and superficial course. Normally the radial artery takes its origin as one of the terminal branches of brachial artery at the level of the neck of radius. It usually lies along the lateral border of fore arm deep to the brachioradialis muscle. While dissecting a 72-year-old Caucasian female cadaver, it was found that the right sided radial artery originated from the upper part of brachial artery of arm, 2 cm below the lower border of teres major muscle, from the lateral aspect of brachial artery. Then the radial artery superficially crossed the brachial artery and median nerve from lateral to medial direction and rested superficially at the cubital fossa. Embryologically, it can be explained as a failure of disappearance, or abnormal persistence of some insignificant embryonic vessels may give rise to this kind of vascular anomalies. As radial artery is one of the most important upper limb arteries, its variation and related complications are clinically significant. This unusual origin and course of radial artery should be kept in mind by all healthcare providers including surgeons and radiologists during routine venipuncture, orthopedic and plastic surgeries of arm, coronary angiographic procedures in radial approach etc. to prevent unwanted complications.

Keywords: brachial artery anomalies, brachio-radial artery, high origin radial artery, superficial radial artery

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Authors: Waseem Al Talalwah, Shorok Al Dorazi, Roger Soames

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Persistent sciatic artery is a rare anatomical vascular variation resulting from a lack of regression of the embryonic dorsal axial artery. The axial artery is the main artery supplying the lower limb during development in the first trimester. The current research includes 206 sciatic artery cases in 171 patients between 1864 and 2012. It aims to identify the risk factor of sciatic artery aneurysm in congenital limb anomalies. Sciatic artery aneurysm was diagnosed incidentally in amniotic band syndrome (ABS) existing with no congenital anomaly in 0.7% or with double knee in 0.7%, with the tibia in 0.7% and with hemihypertrophy or soft tissue hypertrophy in 1.4%. Therefore, the current study indicates a relationship the same gene responsible for the congenital limb deformities may be responsible for non-regression of the sciatic artery. Furthermore, pediatricians should refer cases of congenital limb anomalies for vascular evaluation prior to corrective surgical intervention.

Keywords: amniotic band syndrome, congenital limb deformities, double knee, sciatic artery, sciatic artery aneurysm , soft tissue hypertrophy

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Authors: Waseem Al Talalwah, Shorok Ali Al Dorazi, Roger Soames

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The inferior gluteal artery is a largest branch of the anterior division of internal iliac artery. It escapes from the pelvic cavity through the greater sciatic foramen below the lower edge of piriformis. In gluteal region, it provides several muscular branches to gluteal maximus and articular branch to hip joint. Further, it provides sciatic branch to sciatic nerve. Present study explores the origin of the inferior gluteal artery of 41 cadavers in Centre for Anatomy and Human Identification, University of Dundee, UK. It arose directly from the anterior division of internal iliac artery in 39% and 45.7% indirectly as with the internal pudendal artery. Further, it arose indirectly from anterior division with internal pudendal and obturator arteries in 1.5% referred as obturatogluteopudendal trunk in 1.5%. Therefore, it arose from the anterior division of the internal iliac artery in 86.2%. However, it found to be as a branch of the posterior division of internal iliac artery in 7.7% which is either a direct branch in 6.2% as or indirect branch (as from the sciatic artery) in 1.5%. It neither arose from anterior or posterior division in 1.5% as from gluteopudendal trunk arising from the internal iliac artery bifurcation site. In few cases, the inferior gluteal artery found to be congenital absence in 4.6% which is compensated by the persistent sciatic artery. Therefore, radiologists have to aware of the origin variability of the inferior gluteal artery to alert surgeons. Knowing the origin of the inferior gluteal artery may help the surgeons to avoid iatrogenic sciatic neuropathy or gluteal claudication due to prolonged ligation in pelvic procedures such as removing prostate or of uterine fibroid.

Keywords: inferior gluteal artery, internal pudendal, sciatic nerve, sciatic artery, gluteal claudication, sciatic neuopathy

Procedia PDF Downloads 678

Authors: Halimah Al Hifzi, Waseem Al-Talalwah, Shorok Al Dorazi, Hassan Al Mousa, Zainab Al-Hashim, Roger Soames

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The obturator artery is one branches of anterior division of the internal iliac artery. It passes on the lateral wall of pelvis to escape into thigh region via obturator foremen. Based on previous research studies, it found to be extremely variable in origin and course. It may arise from internal or external iliac artery. The current study includes 82 dissected specimens to investigate the origin of the obturator artery and explain the clinical importance. The obturator artery arises from the internal iliac artery in 75% either from its anterior or posterior division in 46.9% or 25% respectively. Further, it arises neither from the anterior nor posterior division of the internal iliac artery but it arises between them in 3.1%. In 25%, the obturator artery arises from the external iliac artery. In case of aneurysmectomy of posterior division, carries a high risk of insufficient of vascular supply for demand structures such as proximal adductors attachment and hip joint. Therefore, vascular surgeons have to pay attention to the posterior division being an origin of the obturator artery beside its usual three classical branches: superior gluteal, iliolumbar and lateral sacral arteries. Further, the obturator artery arising from the external iliac system is in great dangerous of laceration in case of anterior pelvic fracture. Therefore, it may lead to haemorrhagic shock threatening life.

Keywords: obturator artery, external iliac, internal iliac artery, anterior division, posterior division, superior gluteal, iliolumbar and lateral sacral, pubic fracture, aneurysm, shock

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Authors: Bhavya Tripathi, Bhupendra Kumar Sharma

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In blood, the concentration of red blood cell varies with the arterial diameter. In the case of narrow arteries, red blood cells concentrate around the center of the artery and there exists a cell-free plasma layer near the arterial wall due to Fahraeus-Lindqvist effect. Due to non- uniformity of the fluid in the narrow arteries, it is preferable to consider the two-phase model of the blood flow. In the present article, coupled nonlinear differential equations have been developed for momentum, energy and concentration of two phase model of the blood flow assuming the Newtonian fluid in both central core and cell free plasma layer and the exact solutions have been found for the problem. For having an adequate insight into the stenosed arterial two-phase blood flow, major components of the flow as flow resistance, total flow rate, and wall shear stress have been estimated for different values of magnetic and radiation parameter. Results show that the increase in the effects of magnetic field decreases the velocity of both cores as well as plasma regions. This result can be helpful to control the blood flow in narrow arteries during surgical process. Temperature of core as well plasma regions decrease as value of radiation parameter increases. The present result is implemented in the form of radiation therapy which is very helpful for cancer patients.

Keywords: two phase blood flow, radiation, magnetohydrodynamics (MHD), stenosis

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Authors: Chethan Purushothama

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Coronary artery disease is one of the major causes of death in developing countries. The coronary arteries show wide range of variations and these variations have not been dealt with different population groups. The present study aims to focus on the pattern and variations of coronary artery in south Indian population. The study was performed to analyze the coronary artery dominance and divisions of main trunk of left coronary artery in 81 isolated adult human cadaveric hearts of South Indian population. The specimens were fixed in 10% formalin and were dissected manually. In our specimens, 74.1% of the hearts were right dominant, 11.1% were left dominant, and 14.8% were co-dominant. Bifurcation, trifurcation, and quadrifurcation of main trunk of left coronary artery were seen in 49.4%, 48.1%, and 2.5% cases respectively. The right dominant hearts had bifurcation, trifurcation and quadrifurcation of main trunk of left coronary artery in 46.7%, 50% and 3.3% hearts respectively. The left dominant hearts had bifurcation and trifurcation of main trunk of left coronary artery in 55.6% and 44.4% cases respectively. The co-dominant hearts had bifurcation and trifurcation of main trunk of left coronary artery in 58.3% and 41.7% respectively. Quadrifurcation of main trunk of left coronary artery were seen only in right dominant hearts. We believe that the data obtained from the present study are important to the interventional cardiologists and radiologists. The details obtained will also be helpful for the clinical anatomists.

Keywords: bifurcation, coronary artery, trifurcation, quadrifurcation

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Authors: Waseem Al-Talalwah

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The superior vesical artery usually arises directly from the anterior division of the internal iliac artery. It may arise from the umbilical artery as three or four branches to supply the upper and middle parts of bladder. Current study focuses on the different origins of the superior vesical artery to provide a sufficient data for surgeons to disease iatrogenic fault. The superior vesical artery arises directly from the anterior division of the internal iliac artery in 24.5% whereas it arises indirectly as from umbilical artery in 83.7%. Further, it may arise from any branch of the anterior division as from the utrine and obturator arteries in 6.1% and in 6.3% respectively. It also shares the origin of the internal pudendal and inferior glutyeal artery as it arises from the gluteopudendal trunk in 4.1%. The superior vesical artery arises as a single, double, triple and quadruple in 69.4%, 20.4%, 8.2% and 2% respectively. In case of cystectomy for bladder cancer, surgeons have to be aware of the origin variability of superior vesical artery to prevent post-surgical complication such as intra-pelvic bleeding. Also, the as intra-pelvic bleeding has to be expected in case of hysterectomy therefore a great caution of the vesical branches arising from uterine artery has to be considered. In case of aneurysm resection of inferior gluteal artery arising from the gluteopudendal trunk, the surgeons have to be careful of the vascular supply of urinary bladder coming from above and below this common trunk as from superior and inferior vesical arteries respectively. Therefore, present study increases the awareness of clinical significance of superior vesical artery origin for surgeons to minimise the iatroginc errors.

Keywords: superior vesical artery, anterior division, internal iliac, internal pudendal, inferior glutyeal, intra-pelvic bleeding, hysterectomy, cystectomy

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Authors: Behnam Shakerian, Negin Razavi

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The pathogenesis of coronary artery disease is multifactorial. The epicardial fat pad is a localized fat depot lying between the myocardium and the visceral layer of the pericardium. The mechanisms through which epicardial fat pad can cause atherosclerosis are complex. The epicardial fat pad can surround the coronary arteries and contributes to the development and progression of coronary artery disease. Methods: we selected 50 patients who underwent coronary artery angiography for the evaluation of coronary artery disease that results were positive for coronary artery disease. All patients underwent an echocardiographic examination after coronary angiography to measure epicardial fat pad thickness. The epicardial fat pad was defined as an echo-free space between the myocardium's outer wall and the pericardium's visceral layer. Results: The epicardial fat pad was measured on the right ventricle apex in 46 patients. Sixty- five percent of the studied patients were male. The most common vessel with stenosis was the left anterior descending artery. A significant correlation was observed between epicardial fat pad thickness and the severity of coronary artery disease. Discussions: The epicardial fat pad provides a horizon on the pathophysiology of cardiovascular diseases. It directly contributes to the development and progression of coronary artery disease by causing inflammation and endothelial damage. Further investigations are needed to determine whether medical treatment can reduce the mass of epicardial fat pad and can help to improve atherosclerosis. Conclusion: The epicardial fat pad measurement could be used as an indicator of coronary arteries’ atherosclerosis. Therefore, thickness measurement of the epicardial fat pad in the clinical practice could be of assistance in identifying patients at risk and if required, undergoing supplementary diagnosis with coronary angiography.

Keywords: epicardial, fat pad, coronary artery disease, echocardiography

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Authors: Syed Dawood M. Taimur

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Background: Peripheral arterial disease (PAD) is under diagnosed in primary care practices, yet the extent of unrecognized PAD in patients with coronary artery disease (CAD) is unknown. Objective: To assess the prevalence of previously unrecognized PAD in patients undergoing coronary angiogram and to determine the relationship between the presence of PAD and severity of CAD. Material & Methods: This five years retrospective study was conducted at an invasive lab of the department of Cardiology, Ibrahim Cardiac Hospital & Research Institute from January 2010 to December 2014. Total 77 patients were included in this study. Study variables were age, sex, risk factors like hypertension, diabetes mellitus, dyslipidaemia, smoking habit and positive family history for ischemic heart disease, coronary artery and peripheral artery profile. Results: Mean age was 56.83±13.64 years, Male mean age was 53.98±15.08 years and female mean age was 54.5±1.73years. Hypertension was detected in 55.8%, diabetes in 87%, dyslipidaemia in 81.8%, smoking habits in 79.2% and 58.4% had a positive family history. After catheterization 88.3% had peripheral arterial disease and 71.4% had coronary artery disease. Out of 77 patients, 52 had both coronary and peripheral arterial disease which was statistically significant (p < .014). Coronary angiogram revealed 28.6% (22) patients had triple vessel disease, 23.3% (18) had single vessel disease, 19.5% (15) had double vessel disease and 28.6% (22) were normal coronary arteries. The peripheral angiogram revealed 54.5% had superficial femoral artery disease, 26% had anterior tibial artery disease, 27.3% had posterior tibial artery disease, 20.8% had common iliac artery disease, 15.6% had common femoral artery disease and 2.6% had renal artery disease. Conclusion: There is a strong and definite correlation between coronary and peripheral arterial disease. We found that cardiovascular risk factors were in fact risk factors for both PAD and CAD.

Keywords: coronary artery disease (CAD), peripheral artery disease(PVD), risk, factors, correlation, cathetarization

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Authors: Karen Cilliers, Benedict John Page

Abstract:

The middle cerebral artery (MCA) is the most complex cerebral artery although few anomalies are found compared to the other cerebral arteries. The branches of the MCA cover a large part of each hemisphere, therefore it is exposed in various operations. Although the segments of the MCA are similarly described by most authors, there is some disagreement on the branching pattern of the MCA. The aim of this study was to review the available literature on the anatomy and variations of the MCA, and to compare this to a pilot study. For the pilot study, 20 hemispheres were perfused with coloured silicone and the MCA was dissected. According to the literature, the two most common branching configurations are the bifurcating and trifurcating patterns. In the pilot study, bifurcation was observed in 19 hemispheres, and in one hemisphere there was no branching (monofurcation). No trifurcation was observed. The most commonly duplicated branch was the anterior parietal artery in 30%, and most commonly absent was the common temporal artery in 65% and the temporal polar artery in 40%. Very few studies describe the origins of the branches of the MCA, therefore a detailed description is given. Middle cerebral artery variations that are occasionally reported in the literature include fenestration, and a duplicated or accessory MCA, although no variations were observed in the pilot study. Aneurysms can frequently be observed at the branching of cerebral vessels, therefore a thorough knowledge of the vascular anatomy is vital. Furthermore, knowledge of possible variations is important since variations can have serious clinical implications.

Keywords: anatomy, anomaly, description, middle cerebral artery, origin, variation

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Authors: Muhsin Kizhisseri, Jorg Schluter, Saleh Gharie

Abstract:

Atherosclerosis is the main reason of stroke, which is one of the deadliest diseases in the world. The carotid artery in the brain is the prominent location for atherosclerotic progression, which hinders the blood flow into the brain. The inclusion of computational fluid dynamics (CFD) into the diagnosis cycle to understand the hemodynamics of the patient-specific carotid artery can give insights into stroke prediction. Realistic outlet boundary conditions are an inevitable part of the numerical simulations, which is one of the major factors in determining the accuracy of the CFD results. The Windkessel model-based outlet boundary conditions can give more realistic characteristics of the distal vascular branches of the carotid artery, such as the resistance to the blood flow and compliance of the distal arterial walls. This study aims to find the most influential distal branches of the carotid artery by using the Windkessel model parameters in the outlet boundary conditions. The parametric study approach to Windkessel model parameters can include the geometrical features of the distal branches, such as radius and length. The incorporation of the variations of the geometrical features of the major distal branches such as the middle cerebral artery, anterior cerebral artery, and ophthalmic artery through the Windkessel model can aid in identifying the most influential distal branch in the carotid artery. The results from this study can help physicians and stroke neurologists to have a more detailed and accurate judgment of the patient's condition.

Keywords: stroke, carotid artery, computational fluid dynamics, patient-specific, Windkessel model, distal vascular branches

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Authors: Sreeparna Majee, G. C. Shit

Abstract:

A study on targeted drug delivery is carried out in an unsteady flow of blood infused with magnetic NPs (nanoparticles) with an aim to understand the flow pattern and nanoparticle aggregation in a diseased arterial segment having stenosis. The magnetic NPs are supervised by the magnetic field which is significant for therapeutic treatment of arterial diseases, tumor and cancer cells and removing blood clots. Coupled thermal energy have also been analyzed by considering dissipation of energy because of the application of the magnetic field and the viscosity of blood. Simulation technique used to solve the mathematical model is vorticity-stream function formulations in the diseased artery. An elevation in SLP (Specific loss power) is noted in the aortic bloodstream when the agglomeration of nanoparticles is higher. This phenomenon has potential application in the treatment of hyperthermia. The study focuses on the lowering of WSS (Wall Shear Stress) with increasing particle concentration at the downstream of the stenosis which depicts the vigorous flow circulation zone. These low shear stress regions prolong the residing time of the nanoparticles carrying drugs which soaks up the LDL (Low Density Lipoprotein) deposition. Moreover, an increase in NP concentration enhances the Nusselt number which marks the increase of heat transfer from the arterial wall to the surrounding tissues to destroy tumor and cancer cells without affecting the healthy cells. The results have a significant influence in the study of medicine, to treat arterial diseases such as atherosclerosis without the need for surgery which can minimize the expenditures on cardiovascular treatments.

Keywords: magnetic nanoparticles, blood flow, atherosclerosis, hyperthermia

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Authors: G. K. Guseynova, V. V. Krylov, L. T. Khamidova, N. A. Polunina, V. A. Lukyanchikov

Abstract:

The report presents complex ultrasound diagnostics in patients with symptomatic steno-occlusive lesions of extra- and intracranial branches of brachiocephalic arteries (BCA). The tasks and possibilities of ultrasound diagnostics at different stages of treatment of patients with symptomatic occlusion of internal carotid artery (ICA) are covered in detail; qualitative and quantitative characteristics of blood flow; parameters of the wall and lumen of the main arteries of the head; methods of ultrasound examination of indirect assessment of the functional status are presented. Special attention is paid to the description of indicators that are predictors of the consistency of formed extra-intracranial low-flow shunts, examples of functioning and failed anastomoses are analyzed.

Keywords: CBF, cerebral blood flow; CTA, external carotid artery; ICA, internal carotid artery; MCA, middle cerebral artery; MRA, magnetic resonance angiography; OEF, oxygen extraction fraction; TIA, transient ischaemic attack, ultrasound, low-flow bypass, anastomoses

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Authors: Sally Shepherd, Jessica Wong, David Read

Abstract:

Traumatic brachiocephalic artery aneurysm is a rare injury that typically occurs as a result of a blunt chest injury. A 19-year-old female sustained a head-on, high speed motor vehicle crash into a tree. Upon release after 45 minutes of entrapment, she was tachycardic but normotensive, with a significant seatbelt sign across her chest and open deformed right thigh with weak pulses in bilateral lower limbs. A chest XR showed mild upper mediastinal widening. A CT trauma series plus gated CT chest revealed a grade 3a aortic arch transection with brachiocephalic pseudoaneurysm. Endovascular repair of the brachiocephalic artery was attempted post-presentation but was unsuccessful as the first stent migrated to the infrarenal abdominal aorta and the second stent across the brachiocephalic artery origin had a persistent leak at the base. She was transferred to Intensive Care for strict blood pressure control. She returned to theatre 5 hours later for a median sternotomy, aortic arch repair with an 8mm graft extraction, and excision of the innominate artery pseudoaneurysm. She had an uncomplicated post-operative recovery. This case highlights that brachiocephalic artery injury is a rare but potentially lethal injury as a result of blunt chest trauma. Safe management requires a combined Vascular and Cardiothoracic team approach, as stenting alone may be insufficient.

Keywords: blunt chest injury, Brachiocephalic aneurysm, innominate artery, trauma

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Authors: Alireza Abdiardekani, Maryam Salimi, Shirin Sarejloo, Mehdi Bazrafshan, Amir Askarinejad, Amirhossein Salimi, Hanieh Bazrafshan, Salar Javanshir, Armin Attar, Shokoufeh Khanzadeh, Mohsen Esmaeili, Hamed Bazrafshan Drissi

Abstract:

Background: Opium, after tobacco, is the most abused substance in the Middle East. The effects of opium use on coronary artery disease are indeed unclear. This study aimed to assess the association between opium use and angiographic findings in patients with acute coronary syndrome (ACS) diagnosis at Al-Zahra Heart Hospital, Shiraz, Iran. Methods: In this case-control study, 170 patients admitted for coronary angiography were enrolled from 2019 to 2020. They were categorized into two groups based on their history: "non-opium" and "opium." SPSS (Version 26) was used to investigate the correlation between opioid addiction and the severity of coronary artery disease. Results: The results of our study reveal that the mean age of the participants was 61.63±9.07. This study indicated that 49 (28.82%) patients were female, and 121 (71.17%) were male. Our findings revealed that three-vessel disease was more frequent in non-opium (40; 47.05%) and opium (45; 52.94%) groups. There was a significant correlation between the severity of the second diagonal artery(D2) and right coronary artery(RCA) involvement and opium consumption. There was a strong positive correlation between the location of the vascular lesion in the left circumflex artery and opium consumption. Conclusion: Opium, as an independent risk factor for cardiovascular diseases, can have specific effects on angiographic findings in patients with coronary artery disease. Public health officials and politicians should arrange several programs to increase the general population’s consciousness about opioid use and its consequences.

Keywords: acute coronary syndrome, opium, coronary artery disease, angiography

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