Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Percutaneous Coronary Intervention of A Stenotic Left Anterior Descending Artery with Anomalous Origin of Right Coronary Artery  [PDF]
Shu-Kai Hsueh,Ali A Youssef,Chi-Yuan Fang
Chang Gung Medical Journal , 2009,
Abstract: The anomalous origin of the right coronary artery (RCA) from the left anterior descending(LAD) artery is rare. We report a case of single coronary artery with proximal LADsevere stenosis. The RCA originated from an unreported course of conal branch from theLAD. This anomalous RCA also had collaterals from left circumflex. Coronary interventionwas successfully carried out on a severe stenosis at the proximal LAD artery. To the best ofour knowledge the scenario of anomalous course and intervention is still to be reported.
The Wall Shear Stress of a Pulsatile Blood Flow in a Patient Specific Stenotic Right Coronary Artery  [PDF]
Biyue Liu
Engineering (ENG) , 2013, DOI: 10.4236/eng.2013.510B080

A computer simulation of the blood flow in a patient specific atherosclerotic right coronary artery is carried out to study the blood flow pattern and the wall shear stress (WSS) distribution in the artery. Both temporal and special distribution patterns of the WSS of the non-Newtonian blood flow are presented and the regions on the lumen surface where the WSS is constantly lower than 1N/m2are identified.


Modeling of Stenotic Coronary Artery and Implications of Plaque Morphology on Blood Flow  [PDF]
Carlos Moreno,Kiran Bhaganagar
Modelling and Simulation in Engineering , 2013, DOI: 10.1155/2013/390213
Abstract: A diseased coronary artery has been modeled to study the implications of plaque morphology on the fluid dynamics. In our previous study, we have successfully classified the coronary plaques of 42 patients who underwent intravascular ultrasound (IVUS) into four-types (Type I, Type II, Type III, and Type IV) based on the plaque morphology. In this study, we demonstrate that, for the same degree of stenosis (height of the plaques), hemodynamics parameters are strongly dependent on the plaque shape. This study is the first one to clearly demonstrate that in addition to wall shear stress, presence of turbulence and location of transition from laminar to turbulence state are additional hemodynamics parameters to identify plaques vulnerable to rupture. 1. Introduction Coronary artery disease (CAD) is a progressive disease characterized by the accumulation of plaques on the artery walls. CAD is initiated by the deposition of fatty materials in the coronary artery resulting in the thickening and formation of streaks of plaque on the artery walls. During these early stages, the plaques are not of significant consequence to the flow dynamics, and the flow does not deviate from the laminar state present in a normal coronary artery [1–3]. As time progresses, these plaques start growing inwards into the lumen (channel in which the blood flows), resulting in the localized narrowing of the artery or stenosis of the artery lumen, and thus, playing a critical role in altering the flow characteristics. It is clear that once a stenosis is developed, the blood flow is further disturbed and hemodynamic parameters continue to play a crucial role as the stenosis progresses [4]. Hence, as the stenosis increases this alters the flow characteristics causing a laminar to turbulent transition in the blood flow. The evidence of turbulence in regions distal to a stenosis was first demonstrated based on detection of high frequency pressure signals for lesions with 23%–76% stenoses [5]. Based on clinical findings as murmurs [6], laboratory experiments [1, 7, 8], and medical imaging methods [9–11], it is now well established that stenosed coronary artery creates high levels of turbulence, thus significantly modifying the flow characteristics. As of today, the degree of stenosis has been a classical metric to define the extent of the disease for medical purposes. The stenoses are commonly assessed as a percentage of obstruction in the diameter of the lumen. It is a common practice to characterize the stenosis using the percentage obstruction or the height of the obstruction criterion.
Iatrogenic Right Coronary Artery Dissection  [PDF]
Müslüm ?ahin,Mehmet Vefik Yaz?c?o?lu,Regayip Zehir,Elnur Alizade
Ko?uyolu Kalp Dergisi , 2012,
Abstract: Iatrogenic coronary artery dissection is a rare condition. But, it is potentially catastrophic complication. We present a case of iatrogenic right coronary artery dissection resulting from vigorous hand-injection of contrast medium. The patient was treated successfully by stenting and was obtain optimal coronary blood flow.
A Rare Coronary Artery Anomaly; Double Right Coronary Artery  [PDF]
Lütfü Bekar,Kerem ?zbek,Turgay Burucu,Orhan ?nalan
Ko?uyolu Kalp Dergisi , 2010,
Abstract: A double right coronary artery is an extremely rare coronary artery anomaly. Difficulties in diagnosis might cause underestimation of the incidence of double right coronary artery. Interestingly, most of the cases about this anomaly were reported from Turkey. In this case report, we aimed to present double right coronary artery in a patient who was admitted with atypic chest pain.
Anomalous Right Coronary Artery Originating from the Left Main Coronary Artery
Y Mahmmody,J Zamani
Iranian Cardiovascular Research Journal , 2009,
Abstract: A 50–year–old woman presented to our center with effort angina. Angiography showed normal left main coronary artery, normal left circumflex (LCX) artery and critical discrete lesion (99% stenosis) in mid part of left anterior descending (LAD) artery with good distal flow. However, the right coronary artery (RCA) originated from the left main coronary artery. There was no evidence of external compression of the proximal portion of the RCA during systole or diastole. Consult with cardiac surgeon was done but the patient refused from the operation.
Single coronary artery from the right sinus of Valsalva  [cached]
Elio Venturini,Lucia Magni
Heart International , 2011, DOI: 10.4081/hi.2011.e5
Abstract: A case of a single coronary artery originating from the right coronary sinus and bifurcating into left coronary artery (LCA) and right coronary artery (RCA) in a 74-year-old woman, with a non ST elevation acute myocardial infarction (NSTEMI) is described. The diagnosis was made with coronary angiography, that ruled out stenosis, and showed normal LCA and RCA branching. The connection path of LCA, with the opposite cusp, was defined retroaortic by multislice computed tomography (CT). The variants of this coronary anomaly, together with their clinical implications and pathophysiology of AMI are discussed. Multislice CT is fundamental for clinical decision making.
Computational Fluid Dynamics Analysis of the Effect of Plaques in the Left Coronary Artery
Thanapong Chaichana,Zhonghua Sun,James Jewkes
Computational and Mathematical Methods in Medicine , 2012, DOI: 10.1155/2012/504367
Abstract: This study was to investigate the hemodynamic effect of simulated plaques in left coronary artery models, which were generated from a sample patient’s data. Plaques were simulated and placed at the left main stem and the left anterior descending (LAD) to produce at least 60% coronary stenosis. Computational fluid dynamics analysis was performed to simulate realistic physiological conditions that reflect the in vivo cardiac hemodynamics, and comparison of wall shear stress (WSS) between Newtonian and non-Newtonian fluid models was performed. The pressure gradient (PSG) and flow velocities in the left coronary artery were measured and compared in the left coronary models with and without presence of plaques during cardiac cycle. Our results showed that the highest PSG was observed in stenotic regions caused by the plaques. Low flow velocity areas were found at postplaque locations in the left circumflex, LAD, and bifurcation. WSS at the stenotic locations was similar between the non-Newtonian and Newtonian models although some more details were observed with non-Newtonian model. There is a direct correlation between coronary plaques and subsequent hemodynamic changes, based on the simulation of plaques in the realistic coronary models.
An Unusual Appearance of Double Right Coronary Artery  [PDF]
Ahmet Akcay,Sedat Koroglu,Hakan Kaya,Murat Koleoglu,Gurkan Acar
Cardiology Research and Practice , 2010, DOI: 10.4061/2010/123846
Abstract: Double right coronary artery (RCA) is an extremely rare coronary artery anomaly. We aimed to report an atherosclerotic double RCA which appeared after primary percutaneous intervention performed to treat acute inferior myocardial infarction. This is the first case in the literature, which the coronary arteries that can be accepted as double RCA have been hidden by total atherosclerotic occlusion of the proximal part of the RCA. In this paper, also the definition, correct diagnosis, and appropriate diagnostic methods for double RCA were discussed. 1. Introduction Double right coronary artery (RCA) is a very rare coronary anomaly. It might be complicated with atherosclerosis and present with symptomatology of atherosclerosis. In this issue, we reported an atypical double RCA which appeared after primary percutaneous coronary intervention (PCI), performed to treat acute inferior myocardial infarction. 2. Case Report 40-year-old male was admitted to emergency department with retrosternal chest pain at rest for 1 hour. Physical examination was normal except for mild systolic hypertension. Electrocardiogram showed ST segment elevations in leads II, III, and aVF and reciprocal ST segment depressions in leads I and aVL. Coronary angiography showed total occlusion of the proximal RCA (Figure 1). The left coronary arteries were of normal origin and distribution; there were noncritical lesions in left anterior descending artery (LAD) and circumflex artery. Primary PCI was performed to the culprit RCA lesion by using bare metal stent. Control coronary angiogram demonstrated surprisingly that there were two parallel coronary arteries distal to the stent which could be diagnosed as atypical double RCA (Figures 1 and 2). He was administered tirofiban infusion, followed up for four day at intensive care unit and discharged without any complication. Figure 1: (a) LAO view of the totally occluded proximal RCA before percutaneous coronary intervention. (b) After predilatation with sprinter balloon, atypical double RCA was appeared (LAO: Left anterior oblique, RCA: Right coronary artery). Figure 2: (a) RAO view, after implantation of bare metal stent. (b) LAO view, after implantation of bare metal stent (RAO: Right anterior oblique, LAO: Left anterior oblique). 3. Discussion Double RCA is a very rare coronary anomaly which has been reported 21 times and in 27 cases in the literature [1–3]. The true definition and correct diagnosis of this uncommon anomaly remain controversial. Some authors have claimed that it is very difficult to distinguish double RCA with single
Right coronary artery anatomy: anatomical and morphometric analysis
Ballesteros, Luis Ernesto;Ramirez, Luis Miguel;Quintero, Ivan Dario;
Revista Brasileira de Cirurgia Cardiovascular , 2011, DOI: 10.1590/S0102-76382011000200013
Abstract: background: it is necessary knowing the large variability of right coronary (rca) artery specialty for its implications in surgical procedures and clinic events. this variability is usually related to the length, branches quantity, origin and irrigated territories. objective: to evaluate by direct examination the morphologic expression of rca in colombian people. methods: rca were measured in 221 fresh hearts by rca ostium canalization with polyester synthetic resin that was injected in their branches. results: the caliber of the rca proximal segment and at the level of the acute angle of the heart was 3.42 ± 0.66 mm and 2.9 ± 0.50 mm, respectively. it ended between crux cordis and the left margin in 75.6% of specimens. posterior interventricular artery (pia) reached the inferior third, or the apex, or the anterior interventricular sulcus in 149 (67.4%) cases. sinoatrial node artery (sna) originated in the right coronary in 134 (60.6%) cases, 77 (34.9%) from circumflex artery (cxa) and from both in 10 (4.5%). posterior right diagonal artery (prda) was noted in 38 (17.2%) hearts, but only 6% of the sample with long pia, concomitantly presented the prda (p = 0.001). in right dominance sna were originated from rca in 54.7% and form cxa in 46.3% (p = 0.06). conclusions: caliber of the rca and its branches is lesser than the majority of previous studies, while the prda frequency is slightly higher than the reported in literature. clinical and pathological scenarios by these variations should be taken into account: hemodynamic procedures, cardiac surgery and arrhythmias from coronary occlusive disease.
Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.