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Non-Newtonian flow from a wedge constitutes a fundamental problem in chemical engineering systems and is relevant to processing of polymers, coating systems, etc. Motivated by such applications, the homotopy analysis method (HAM) was employed to obtain semi-analytical solutions for thermal convection boundary layer flow of incompressible micropolar fluid from a two-dimensional body (wedge). Viscous dissipation and heat sink effects were included. The non-dimensional boundary value problem emerges as a system of nonlinear coupled ordinary differential equations, by virtue of suitable coordinate transformations. The so-called Falkner-Skan flow cases are elaborated. Validation of the HAM solutions was achieved with earlier simpler models, as well as with a Nakamura finite difference method for the general model. The micropolar model employed simulates certain polymeric solutions quite accurately, and features rotary motions of micro-elements. Primary and secondary shear stress, wall couple stress, Nusselt number, microrotation velocity, and temperature were computed for the effect of vortex viscosity parameter (micropolar rheological), Eckert number (viscous dissipation), Falkner-Skan (pressure gradient) parameter, micro-inertia density, and heat sink parameter. The special cases of Blasius and stagnation flow were also addressed. It was observed from the study that the temperature and thermal boundary layer thickness are both suppressed with increasing wedge parameter and wall heat sink effect, which is beneficial to temperature regulation in polymer coating dynamics. Further, strong reverse spin was generated in the microrotation with increasing vortex viscosity, which resulted in increase in angular momentum boundary layer thickness. Also, both primary and secondary skin friction components were reduced with increasing wedge parameter. Nusselt number was also enhanced substantially with greater wedge parameter. [ABSTRACT FROM AUTHOR]

BACKGROUND: Coronary artery disease is the most common single cause of death in all countries of the world, corresponding to 12.8% of all deaths. Complications in the acute phase may lead the patient to a state of cardiogenic shock being the leading cause of death in patients hospitalized for acute myocardial infarction with 50% mortality despite reperfusion therapy, optimal medical treatment and intraaortic balloon support. OBJECTIVE: To reduce mortality secondary to cardiogenic shock due to anteroapical ST-segment elevation acute myocardial infarction (STEMI). MATERIALS AND METHODS: We included patients with anteorapical STEMI who coronary blood flow was restored by primary angioplasty and continue with cardiogenic shock despite various supportive therapies. By angioplasty technique the "containment balloon", an angioplasty balloon was placed on the left anterior descending artery, which was the diameter according to the vessel and 80 mm in length covering the entire course of the artery and it was inflated with contrast undiluted, leaving it for 12 hours, new measurements were made (pulmonary capillary wedge pressure, cardiac index) with the pulmonary artery catheter during this time. At the end of 12 hours the balloon was deflated and removed from the coronary, then bare metal stents were placed distal to proximal. RESULTS: In this study we observed higher mortality with standard treatment than the reported in the literature. However, making an intervention with the containment balloon this mortality is reduced by 66.6 % (p<0.01) in the control group. It could be demonstrated an increase in ejection fraction at 48 hours average of 34% (p<0.01) in patients treated by containment balloon. CONCLUSION: It is a novel, useful, reproducible and no learning curve technique with superior survival benefit in patients with cardiogenic shock due to anteroapical STEMI. The cost of this technique is less than the cost of different ventricular assist devices. [ABSTRACT FROM AUTHOR]

BACKGROUND: Chronic total occlusion of the coronary arteries can be found as a finding in coronary angiography following a nonreperfused myocardial infarction of more than 3 months of evolution, in patients with chronic angina or as an incidental finding in the diagnostic coronariography, in which the territory myocardium of the affected vessel may present cell death. OBJECTIVE: To compare if the presence of venous return in the territory of the artery with chronic total obstruction is an angiographic parameter validated to evaluate an adequate myocardial perfusion against those who did not present it. MATERIALS AND METHODS: An observational, ambispective study, consisting of the review of cases of patients who underwent. We reviewed the coronary angiography cases performed at the Hemodynamic Service of the Central Military Hospital from April 2015 to October 2016 and collected cases in which chronic total occlusion of the anterior descending, with and without presence of venous return, after which cardiac gammagram was performed to assess perfusion in that territory. RESULTS: In patients with left anterior descending coronary artery with chronic total occlusion and venous return, 90% (n=19) had myocardial perfusion and 81% (n=17) presented some degree of myocardial ischemia, whereas in patients with chronic total occlusion without venous return, 75% (n=9) had no myocardial perfusion and 25% (n=3) presented some degree of myocardial ischemia (p<0.01). CONCLUSIONS: Venous return may be a valid angiographic indicator to predict adequate myocardial perfusion in the area of total occlusion of the anterior descending artery. [ABSTRACT FROM AUTHOR]

BACKGROUND: Acute heart failure as a complication of acute anteroapical ST elevation myocardial infarction is the most frequent complication and Is the first cause of death in the acute and chronic phase. At present, medical pharmacological treatment has been improved and guidelines have been proposed for the management of these patients who have a good evolution, but a non negligible percentage of patients have refractory heart failure, hemodynamic instability, pulmonary congestion, which implies a longer hospital stay and nosocomial infections. OBJECTIVE: To reduce mortality of acute anteroapical ST elevation myocardial infarction not reperfused Killip and Kimbal class III MATERIALS AND METHODS: We included patients attended at the Hospital Central Militar interventional cardiology department, with the diagnosis of acute anteroapical ST elevation myocardial infarction not reperfused. The infarct was classified as Killip and Kimbal class III with decreased ejection fraction and after 72 hours of optimal medical treatment for heart failure, persisted in the Killip and Kimbal class III. Coronary angiography and ventriculography were performed, finding total obstruction of the anterior descending artery and akinesia, dyskinesia or anteroapical left ventricular aneurysm. The technique of splinting of anterior descending artery with stents was performed in the hemodynamic laboratory. Their management was continued in the coronary care unit. Transthoracic echocardiography was performed 8 days after the intervention. RESULTS: A total of 21 patients who met the selection criteria were included. The ejection fraction of the left ventricle prior to the procedure was on average 29%. Five subjects developed cardiogenic shock in the first twelve hours of hospitalization, but only one died. Of the remaining subjects, two additional deaths were observed, none at an early age (first 30 days). The 30-day survival was 95.2%, with a median survival of 29.76 days (95% CI 29.3, 30.2). CONCLUSION: In patients with acute anteroapical ST elevation myocardial infarction not reperfused Killip and Kimbal class III with reduced left ventricular ejection fraction (less than 35%) and akinesia-dyskinesia-apical aneurysm, the technique of splinting of anterior descending artery with stents was associated with a better prognosis with a 30-day survival rate was 95.2%, with a median survival of 29.76 days (95% CI 29.3, 30.2), with a significant improvement in left ventricular ejection fraction (previous 30.5 + 6.4%, posterior 33.3 + 6.5%, p = 0.016). [ABSTRACT FROM AUTHOR]