Mechanical Complications after Myocardial Infarction: A Comprehensive Review

Mechanical complications of myocardial infarction are potentially fatal events that can occur after an acute myocardial infarction. While the introduction of primary percutaneous reperfusion and fibrinolysis has reduced the incidence of these complications to less than 1%. These complications pose significant hemodynamic consequences and necessitate prompt diagnosis. Echocardiography, cardiac magnetic resonance imaging, and computed tomography are valuable tools for establishing an accurate and expedited diagnosis. Consequently, it is imperative to conduct further scientific research to enhance hemodynamic stabilization techniques such as intra-aortic balloon counterpulsation and extracorporeal membrane oxygenation, in addition to exploring new surgical procedures that can reduce mortality resulting from mechanical complications. This article aims to provide a comprehensive review of mechanical complications following myocardial infarction and their correlation with multi-imaging, facilitating a better understanding of these complications.

Mechanical Complications of Osteosynthesis: Frequency and Management at the Orthopedics-Traumatology Department of CHU Ignace DEEN

Introduction: Mechanical complications after osteosynthesis are spontaneous and harmful modifications of the joint compromising the consolidation process. The aim of this study is to report on the frequency of these complications and their management in the Orthopaedic-Traumatology Department of CHU Ignace Deen. Patients and Methods: we conducted a retrospective descriptive and analytical cross-sectional study from January 2017 to December 2022. It focused on the records of patients hospitalized and treated in the department for a mechanical complication after osteosynthesis. Results: The frequency of mechanical complications was 1.2%, with an average age of 44.2 years and a sex ratio of 3.2 in favor of men. Non-compliance with postoperative instructions, non-compliance with surgical technique, postoperative infection and early loading were the main contributing factors. Disassembly of the screw-plate was the most common cause in 6 cases (35.5%), with a mean delay of 4.1 months. Revision osteosynthesis was carried out using screw plates in 8 cases (47.1%). Conclusion: Mechanical complications of osteosynthesis are less frequent traumatic conditions in our department. Several factors contribute to their occurrence.

Different types of mechanical complications after surgical correction of adult spine deformity with osteotomy

AIM To determine the incidence and risk factors for mechanical complications （MC） after surgical correction of adult spinal deformity （ASD） with osteotomy.METHODSA retrospective study was performed. Inclusion criteria： Surgical correction of ASD using osteotomy; male or female; 〉 20 years old; follow-up ≥ 24 mo or revision. The MC of spine and spinal instrumentation were studied separately. Risk analysis included assessment of the association between more than 50 different characteristics （demographic, clinical, radiographic, and instrumentation） with different types of MC.RESULTSThe medical records of 94 operations in 88 subjects were analyzed： Female （68%）, mean age 58.6 （SD, 12.7） years. Cumulative incidence of MC at 2 year follow-up was 43.6%. Of these, 78% required revision （ P 〈 0.001）. The following characteristics had significant （ P ≤ 0.05） association with MC： （1） Preoperative： osteoporosis, smoking, previous spinal operation, sagittal vertical axis （SVA） 〉 100 mm, lumbar lordosis （LL） 〈 34°; （2） postoperative： SVA 〉 75 mm; operative correction： SVA 〉 75 mm, LL 〉 30°, thoracic kyphosis 〉 25°, and pelvic tilt 〉 9°; a fall; pseudarthrosis; and （3） device and surgical technique： use of previously implanted instrumentation; use of domino and/or parallel connectors; type of osteotomy （PSO vs SPO） if preoperative SVA 〈 100 mm; lumbar osteotomy location; in-situ rod contouring 〉 60°; and fxation to sacrum/pelvis.CONCLUSIONRisk of MC after surgical correction of ASD is substantial. To decrease this risk over- and/or insuffcient correction of the sagittal imbalance should be avoided.

Reliability analysis for aeroengine turbine disc fatigue life with multiple random variables based on distributed collaborative response surface method

The fatigue life of aeroengine turbine disc presents great dispersion due to the randomness of the basic variables,such as applied load,working temperature,geometrical dimensions and material properties.In order to ameliorate reliability analysis efficiency without loss of reliability,the distributed collaborative response surface method(DCRSM) was proposed,and its basic theories were established in this work.Considering the failure dependency among the failure modes,the distributed response surface was constructed to establish the relationship between the failure mode and the relevant random variables.Then,the failure modes were considered as the random variables of system response to obtain the distributed collaborative response surface model based on structure failure criterion.Finally,the given turbine disc structure was employed to illustrate the feasibility and validity of the presented method.Through the comparison of DCRSM,Monte Carlo method(MCM) and the traditional response surface method(RSM),the results show that the computational precision for DCRSM is more consistent with MCM than RSM,while DCRSM needs far less computing time than MCM and RSM under the same simulation conditions.Thus,DCRSM is demonstrated to be a feasible and valid approach for improving the computational efficiency of reliability analysis for aeroengine turbine disc fatigue life with multiple random variables,and has great potential value for the complicated mechanical structure with multi-component and multi-failure mode.