81 research outputs found
Percutaneous coronary revascularization in patients with formerly "refractory angina pectoris in end-stage coronary artery disease" – Not "end-stage" after all
<p>Abstract</p> <p>Background</p> <p>Patients with refractory angina pectoris in end-stage coronary artery disease represent a severe condition with a higher reduction of life-expectancy and quality of life as compared to patients with stable coronary artery disease. It was the purpose of this study to invasively re-evaluate highly symptomatic patients with formerly diagnosed refractory angina pectoris in end-stage coronary artery disease for feasible options of myocardial revascularization.</p> <p>Methods</p> <p>Thirty-four Patients formerly characterized as having end stage coronary artery disease with refractory angina pectoris were retrospectively followed for coronary interventions.</p> <p>Results</p> <p>Of those 34 patients 21 (61.8%) were eventually revascularized with percutaneous interventional revascularization (PCI). Due to complex coronary morphology (angulation, chronic total occlusion) PCI demanded an above-average amount of time (66 ± 42 minutes, range 25–206 minutes) and materials (contrast media 247 ± 209 ml, range 50–750 ml; PCI guiding wires 2.0 ± 1.4, range 1–6 wires). Of PCI patients 7 (33.3%) showed a new lesion as a sign of progression of atherosclerosis. Clinical success rate with a reduction to angina class II or lower was 71.4% at 30 days. Surgery was performed in a total of8 (23.5%) patients with a clinical success rate of 62.5%. Based on an intention-to-treat 2 patients of originally 8 (25%) demonstrated clinical success. Mortality during follow-up (1–18 months) was 4.8% in patients who underwent PCI, 25% in patients treated surgically and 25% in those only treated medically.</p> <p>Conclusion</p> <p>The majority of patients with end-stage coronary artery disease can be treated effectively with conventional invasive treatment modalities. Therefore even though it is challenging and demanding PCI should be considered as a first choice before experimental interventions are considered.</p
Restoring tibiofemoral alignment during ACL reconstruction results in better knee biomechanics
"Published online: 24 October 2017"PURPOSE:
Anterior cruciate ligament (ACL) reconstruction (ACLR) aims to restore normal knee joint function, stability and biomechanics and in the long term avoid joint degeneration. The purpose of this study is to present the anatomic single bundle (SB) ACLR that emphasizes intraoperative correction of tibiofemoral subluxation that occurs after ACL injury. It was hypothesized that this technique leads to optimal outcomes and better restoration of pathological tibiofemoral joint movement that results from ACL deficiency (ACLD).
METHODS:
Thirteen men with unilateral ACLD were prospectively evaluated before and at a mean follow-up of 14.9 (SD = 1.8) months after anatomic SB ACLR with bone patellar tendon bone autograft. The anatomic ACLR replicated the native ACL attachment site anatomy and graft orientation. Emphasis was placed on intraoperative correction of tibiofemoral subluxation by reducing anterior tibial translation (ATT) and internal tibial rotation. Function was measured with IKDC, Lysholm and the Tegner activity scale, ATT was measured with the KT-1000 arthrometer and tibial rotation (TR) kinematics were measured with 3Dmotion analysis during a high-demand pivoting task.
RESULTS:
The results showed significantly higher TR of the ACL-deficient knee when compared to the intact knee prior to surgery (12.2° ± 3.7° and 10.7° ± 2.6° respectively, P = 0.014). Postoperatively, the ACLR knee showed significantly lower TR as compared to the ACL-deficient knee (9.6°±3.1°, P = 0.001) but no difference as compared to the control knee (n.s.). All functional scores were significantly improved and ATT was restored within normal values (P < 0.001).
CONCLUSIONS:
Intraoperative correction of tibiofemoral subluxation that results after ACL injury is an important step during anatomic SB ACLR. The intraoperative correction of tibiofemoral subluxation along with the replication of native ACL anatomy results in restoration of rotational kinematics of ACLD patients to normal levels that are comparable to the control knee. These results indicate that the reestablishment of tibiofemoral alignment during ACLR may be an important step that facilitates normal knee kinematics postoperatively.
LEVEL OF EVIDENCE:
Level II, prospective cohort study.The authors gratefully acknowledge the funding support from the Hellenic Association of Orthopaedic Surgery and
Traumatology (HAOST-EEXOT)info:eu-repo/semantics/publishedVersio
Biomechanics and anterior cruciate ligament reconstruction
For years, bioengineers and orthopaedic surgeons have applied the principles of mechanics to gain valuable information about the complex function of the anterior cruciate ligament (ACL). The results of these investigations have provided scientific data for surgeons to improve methods of ACL reconstruction and postoperative rehabilitation. This review paper will present specific examples of how the field of biomechanics has impacted the evolution of ACL research. The anatomy and biomechanics of the ACL as well as the discovery of new tools in ACL-related biomechanical study are first introduced. Some important factors affecting the surgical outcome of ACL reconstruction, including graft selection, tunnel placement, initial graft tension, graft fixation, graft tunnel motion and healing, are then discussed. The scientific basis for the new surgical procedure, i.e., anatomic double bundle ACL reconstruction, designed to regain rotatory stability of the knee, is presented. To conclude, the future role of biomechanics in gaining valuable in-vivo data that can further advance the understanding of the ACL and ACL graft function in order to improve the patient outcome following ACL reconstruction is suggested
Role of high tibial osteotomy in chronic injuries of posterior cruciate ligament and posterolateral corner
High tibial osteotomy (HTO) is a surgical procedure used to change the mechanical weight-bearing axis and alter the loads carried through the knee. Conventional indications for HTO are medial compartment osteoarthritis and varus malalignment of the knee causing pain and dysfunction. Traditionally, knee instability associated with varus thrust has been considered a contraindication. However, today the indications include patients with chronic ligament deficiencies and malalignment, because an HTO procedure can change not only the coronal but also the sagittal plane of the knee. The sagittal plane has generally been ignored in HTO literature, but its modification has a significant impact on biomechanics and joint stability. Indeed, decreased posterior tibial slope causes posterior tibia translation and helps the anterior cruciate ligament (ACL)-deficient knee. Vice versa, increased tibial slope causes anterior tibia translation and helps the posterior cruciate ligament (PCL)-deficient knee. A review of literature shows that soft tissue procedures alone are often unsatisfactory for chronic posterior instability if alignment is not corrected. Since limb alignment is the most important factor to consider in lower limb reconstructive surgery, diagnosis and treatment of limb malalignment should not be ignored in management of chronic ligamentous instabilities. This paper reviews the effects of chronic posterior instability and tibial slope alteration on knee and soft tissues, in addition to planning and surgical technique for chronic posterior and posterolateral instability with HTO
The Effect of Knee Flexion Angle and Application of an Anterior Tibial Load at the Time of Graft Fixation on the Biomechanics of a Posterior Cruciate Ligament-Reconstructed Knee
The future of cardiovascular imaging and non-invasive diagnosis☆A joint statement from the European Association of Echocardiography, the Working Groups on Cardiovascular Magnetic Resonance, Computers in Cardiology, and Nuclear Cardiology of the European Society of Cardiology, the European Association of Nuclear Medicine and the Association for European Paediatric Cardiology
Molecular Dynamics Simulations of Acidic Gases at Interface of Quaternary Ammonium Ionic Liquids
Thermodynamics, structure, and dynamics of CO2 and SO2 absorption by ionic liquids based on the bis(trifluoromethylsulfonyl)-imide anion, [NTf2](-), and quaternary ammonium cations have been investigated by molecular dynamics (MD) simulations. the effect of ether-functionalized chains of different lengths in the ammonium cations is emphasized. Oxygen atoms of ether functions in the cation compete with oxygen atoms of anions for interactions with gas molecules. the mole fraction of SO2 is larger than CO2 in a given ionic liquid. the calculation of Gibbs free energy of solvation and profiles of potential of mean force across the gas-liquid interface provide a physical picture consistent with structural effects of gas absorption. the potential of mean force for the gas molecules at interface exhibits a minimum, which is about twice deeper for SO2 than CO2, with corresponding effect on residence times of gas molecules in different layers across the interface toward the bulk.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, Dept Ciencias Exatas & Terra, Lab Mat Hibridos, BR-09913030 Diadema, SP, BrazilUniv São Paulo, Inst Quim, Lab Espect Mol, BR-05508000 São Paulo, BrazilUniversidade Federal de São Paulo, Inst Ciencias Ambientais Quim & Farmaceut, Dept Ciencias Exatas & Terra, Lab Mat Hibridos, BR-09913030 Diadema, SP, BrazilWeb of Scienc
The future of cardiovascular imaging and non-invasive diagnosis: a joint statement from the European Association of Echocardiography, the Working Groups on Cardiovascular Magnetic Resonance, Computers in Cardiology, and Nuclear Cardiology, of the European Society of Cardiology, the European Association of Nuclear Medicine, and the Association for European Paediatric Cardiology
Advances in medical imaging now make it possible to investigate any patient with cardiovascular disease using multiple methods which vary widely in their technical requirements, benefits, limitations, and costs. The appropriate use of alternative tests requires their integration into joint clinical diagnostic services where experts in all methods collaborate. This statement summarizes the principles that should guide developments in cardiovascular diagnostic services
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