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1.
Article in English | MEDLINE | ID: mdl-38707587

ABSTRACT

Background: Improving equitable access to healthcare requires innovative interventions and strengthening a service innovation operational model to achieve transformative change and bring sustainability to public health interventions. The current study aims to identify the components of the Mobile Medical Units (MMUs) operational model as an innovative intervention to provide equitable and inclusive access to healthcare. Methods: The study used qualitative research to identify the components of the operational model of MMUs for primary healthcare in future. Data has been collected via semi-structured in-depth interviews with 103 healthcare professionals from six states representing India's Tier I, Tier II, and Tier III regions. A thematic analysis was performed to examine emergent salient themes. Results: The study identified and examined scalability, affordability, replicability, and sustainability as the four critical components of the operational model of MMUs. The findings of the study indicated that MMUs with these four components played a vital role in COVID-19 immunization, especially in resource-limited settings. The study found that MMUs are a cost-effective and scalable healthcare delivery model that can be easily replicated in primary healthcare service delivery. Conclusion: The findings underscore the significant role of MMUs in addressing healthcare disparities, particularly in resource-limited settings. The adaptability and cost-effectiveness of MMUs make them an ideal solution for primary healthcare delivery, especially in Tier I, II, and III regions of India. It lays a foundation for future research and policy-making, emphasizing the need for innovative, equitable, and sustainable healthcare delivery models like MMUs to transform and strengthen healthcare systems globally.

2.
Maedica (Bucur) ; 19(1): 42-47, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38736935

ABSTRACT

Introduction:Corneal guttata is a non-inflammatory progressive decline of endothelial cell density (ECD) which represents an early clinical feature of Fuch's dystrophy. In patients with corneal guttata, the relative risk for corneal transplantation after phacoemulsification has been found to be 68.2 times higher than in those without it. In the present study, five patients with corneal guttata underwent 25G pars plana vitrectomy (PPV) with concurrent lensectomy and intraocular lens (IOL) implantation in the sulcus. The aim of the present study is to investigate whether this technique has a less damaging effect on endothelial cells as compared to standard phacoemulsification. Methods:This retrospective case series study was conducted at "My Retina" Athens Eye Centre, Greece. Five patients with moderate to dense cataract and clinical signs of corneal guttata were included. All patients had ECD measurement prior to and after surgery. The operation included 25-gauge pars plana vitrectomy (PPV) with subsequent lensectomy and a three-piece IOL implanted in the sulcus with intact anterior capsule. Results:The mean value of ECD was 1157.8±237.51 cells/mm² preoperatively and 1118.2±227.42 cells/mm² postoperatively, indicating a 3.4% reduction from initial values. Retinal detachment was not observed on any of the operated patients after surgery. The IOL was well centered to the sulcus in all patients. Iatrogenic retinal tears were identified in one patient and were treated with laser retinopexy and SF6 gas tamponade. Conclusion:Our results show that PPV along with lensectomy through fragmatome may cause less corneal decompensation than femtosecond laser-assisted cataract surgery (FLACS) or phacoemulsification, especially in patients with corneal guttata. Therefore, reducing the risk for possible future corneal transplantation.

4.
Exp Ther Med ; 27(5): 188, 2024 May.
Article in English | MEDLINE | ID: mdl-38533433

ABSTRACT

The present study aimed to identify rates of venous thromboembolism (VTE) amongst patients treated in inpatient mental health units using linked primary care and mental health care records. Patients resident in the London Borough of Lambeth admitted to mental health units in Southeast London between January 2008 and March 2019 were included, as well as a control group of patients being treated in the community for mental illness. The primary outcome measure was a diagnosis of VTE being recorded in GP records during or within 3 months of an admission to a mental health unit. For 7,198 psychiatric inpatient admissions, 11 episodes of VTE (1.5/1,000 admissions) were identified, with no VTE cases identified in 4,561 patients being treated in the community for mental illness during an equivalent window. This finding indicates that VTE rates following psychiatric inpatient admission might be similar to those following unselected acute medical admission. Larger scale studies are required to confirm the estimated incidence of VTE in patients with mental health conditions and the contribution of acute psychiatry hospitalisation to VTE risk.

5.
Am J Transplant ; 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38527588

ABSTRACT

The first-generation Molecular Microscope (MMDx) system for heart transplant endomyocardial biopsies used expression of rejection-associated transcripts (RATs) to diagnose not only T cell-mediated rejection (TCMR) and antibody-mediated rejection (ABMR) but also acute injury. However, the ideal system should detect rejection without being influenced by injury, to permit analysis of the relationship between rejection and parenchymal injury. To achieve this, we developed a new rejection classification in an expanded cohort of 3230 biopsies: 1641 from INTERHEART (ClinicalTrials.gov NCT02670408), plus 1589 service biopsies added to improve the power of the machine learning algorithms. The new system used 6 rejection classifiers instead of RATs and generated 7 rejection archetypes: No rejection, 48%; Minor, 24%; TCMR1, 2.3%; TCMR2, 2.7%; TCMR/mixed, 2.7%; early-stage ABMR, 3.9%; and fully developed ABMR, 16%. Using rejection classifiers eliminated cross-reactions with acute injury, permitting separate assessment of rejection and injury. TCMR was associated with severe-recent injury and late atrophy-fibrosis and rarely had normal parenchyma. ABMR was better tolerated, seldom producing severe injury, but in later biopsies was often associated with atrophy-fibrosis, indicating long-term risk. Graft survival and left ventricular ejection fraction were reduced not only in hearts with TCMR but also in hearts with severe-recent injury and atrophy-fibrosis, even without rejection.

6.
Article in English | MEDLINE | ID: mdl-38522765

ABSTRACT

Continued circulation of severe acute respiratory syndrome coronavirus 2 has driven the selection of variants with improved ability to escape preexisting vaccine-induced responses, posing a persistent threat to heart transplant recipients (HTRs). The immunogenicity and safety of the updated XBB.1.5-containing monovalent vaccines are unknown. We prospectively enrolled 52 HTRs who had previously received a 5-dose ancestral-derived monovalent and bivalent messenger RNA (mRNA) vaccination schedule to receive the monovalent XBB.1.5 vaccine. Immunogenicity was evaluated using live virus microneutralization assays. The XBB.1.5 monovalent vaccine elicited potent and diverse neutralizing responses and broadened the reactivity spectrum to encompass newer strains, with the highest increase in neutralization activity being more pronounced against XBB.1.5 (15.8-fold) and JN.1 (13.3-fold) than against BA.5 (6.7-fold) and wild-type (4-fold). Notably, XBB.1.5 and JN.1 were resistant to neutralization by prevaccination sera. There were no safety concerns. Our findings support the updating of coronavirus disease 2019 vaccines to match antigenically divergent variants and exclude ancestral spike-antigen to protect HTRs.

7.
Crit Pathw Cardiol ; 2024 Feb 19.
Article in English | MEDLINE | ID: mdl-38381696

ABSTRACT

BACKGROUND: In-hospital cardiac arrest (IHCA) continues to be associated with high morbidity and mortality. The objective of this study was to study the association of arterial carbon dioxide tension (PaCO2) on survival to discharge and favorable neurologic outcome in adults with IHCA. METHODS: The study population included 353 adults who underwent resuscitation from 2011 to 2021 for IHCA at an academic tertiary medical center with arterial blood gas testing done within 24 hours of arrest. Outcomes of interest included survival to discharge and favorable neurologic outcome, defined as Glasgow Outcome Score of 4-5. RESULTS: Of the 353 patients studied, PaCO2 classification included: hypocapnia (PaCO2 < 35mmg, n=89), normocapnia (PaCO2 35-45mmHg, n=151), and hypercapnia (PaCO2 > 45mmHg, n=113). Hypercapnic patients were further divided into mild (45mmHg < PaCO2 ≤ 55mmHg, n=62) and moderate/severe hypercapnia (PaCO2 > 55mmHg, n=51). Patients with normocapnia had the highest rates of survival to hospital discharge (52.3% vs 32.6% vs 30.1%, p<0.001) and favorable neurologic outcome (35.8% vs 25.8% vs 17.9%, p=0.005) compared those with hypocapnia and hypercapnia respectively. In multivariable analysis, compared to normocapnia, hypocapnia (OR 2.06, 95%CI 1.15-3.70) and hypercapnia (OR 2.67, 95%CI 1.53-4.66) were both found to be independently associated with higher rates of in-hospital mortality. Compared to normocapnia, while mild hypercapnia (OR 2.53, 95%CI 1.29-4.97) and moderate/severe hypercapnia (OR 2.86, 95%CI 1.35-6.06) were both independently associated with higher in-hospital mortality compared to normocapnia, moderate/severe hypercapnia was also independently associated with lower rates of favorable neurologic outcome (OR 0.28, 95%CI 0.11-0.73), while mild hypercapnia was not. CONCLUSION: In this prospective registry of adults with IHCA, hypercapnia noted within 24 hours after arrest was independently associated with lower rates of survival to discharge and favorable neurologic outcome.

8.
Transpl Infect Dis ; : e14251, 2024 Feb 13.
Article in English | MEDLINE | ID: mdl-38351512

ABSTRACT

PURPOSE: Antimicrobial misuse contributes to antimicrobial resistance in thoracic transplant (TTx) and mechanical circulatory support (MCS) recipients. This study uses a modified Delphi method to define the expected appropriate antimicrobial prescribing for the common clinical scenarios encountered in TTx and MCS recipients. METHODS: An online questionnaire on managing 10 common infectious disease syndromes was submitted to a multidisciplinary Delphi panel of 25 experts from various disciplines. Consensus was predefined as 80% agreement for each question. Questions where consensus was not achieved were discussed during live virtual live sessions adapted by an independent process expert. RESULTS: An online survey of 62 questions related to 10 infectious disease syndromes was submitted to the Delphi panel. In the first round of the online questionnaire, consensus on antimicrobial management was reached by 6.5% (4/62). In Round 2 online live discussion, the remaining 58 questions were discussed among the Delphi Panel members using a virtual meeting platform. Consensus was reached among 62% (36/58) of questions. Agreement was not reached regarding the antimicrobial management of the following six clinical syndromes: (1) Burkholderia cepacia pneumonia (duration of therapy); (2) Mycobacterium abscessus (intra-operative antimicrobials); (3) invasive aspergillosis (treatment of culture-negative but positive BAL galactomannan) (duration of therapy); (4) respiratory syncytial virus (duration of antiviral therapy); (5) left ventricular assist device deep infection (initial empirical antimicrobial coverage) and (6) CMV (duration of secondary prophylaxis). CONCLUSION: This Delphi panel developed consensus-based recommendations for 10 infectious clinical syndromes seen in TTx and MCS recipients.

10.
Am J Transplant ; 24(3): 380-390, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38072122

ABSTRACT

Patients with severe heart disease may have coexisting liver disease from various causes. The incidence of combined heart-liver transplant (CHLT) is increasing as more patients with congenital heart disease survive to adulthood and develop advanced heart failure with associated liver disease from chronic right-sided heart or Fontan failure. However, the criteria for CHLT have not been established. To address this unmet need, a virtual consensus conference was organized on June 10, 2022, endorsed by the American Society of Transplantation. The conference represented a collaborative effort by experts in cardiothoracic and liver transplantation from across the United States to assess interdisciplinary criteria for liver transplantation in the CHLT candidate, surgical considerations of CHLT, current allocation system that generally results in the liver following the heart for CHLT, and optimal post-CHLT management. The conference served as a forum to unify criteria between the different specialties and to forge a pathway for patients who may need dual organ transplantation. Due to the continuing shortage of available donor organs, ethical issues related to multiorgan transplantation were also debated. The findings and consensus statements are presented.


Subject(s)
Heart Transplantation , Liver Diseases , Liver Transplantation , Humans , Heart
12.
Transpl Infect Dis ; 26(1): e14182, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37885435

ABSTRACT

BACKGROUND: Tixagevimab-cilgavimab (Tix-Cil) was authorized for prophylaxis against COVID-19 in immunocompromised patients from December 2021 through January 2023. Real-world effectiveness for solid organ transplant (SOT) recipients has been unclear. METHODS: We enrolled 911 SOT recipients into a longitudinal COVID-19 serology study, of whom 381 (42%) received ≥1 dose of Tix-Cil. We collected and analyzed data on incident SARS-CoV-2 infections and antibody kinetics for all patients from January 2022 to March 2023, including periods dominated by Omicron BA and BQ subvariants. RESULTS: Over 253 ± 131 days of follow-up, there were 324 new-onset SARS-CoV-2 infections: 117 (31%) in Tix-Cil treated and 207 (39%) in Tix-Cil untreated patients (p = .012). In analyses adjusting for demographic, clinical, and COVID-19 exposure factors, any Tix-Cil treatment was associated with lower infection risk (OR 0.52, 95% CI 0.27-0.96, p = .039) throughout the surveillance period including when more resistant BQ.1 and BQ.1.1 subvariants had emerged (12/1/2022 onwards). Among treated patients, receiving a Tix-Cil dose was associated with substantial and sustained increase in anti-spike IgG antibody and angiotensin-converting enzyme 2 binding inhibition levels (Abbott Architect assay) that together also demonstrated association with lower infection risk (p = .042). During the full surveillance period, the frequency of infections requiring hospitalization was low overall (N = 26, 2.9% of the total cohort) and not significantly different between Tix-Cil recipients (N = 12, 3.2% of treated patients) and non-Tix-Cil recipients (N = 14, 2.6% of untreated patients) with unadjusted p = .31 for between-group difference. CONCLUSION: In a large cohort of SOT recipients, we found that Tix-Cil reduced infection risk even amidst emergent Omicron subvariants. Additionally, the extent of measurable humoral response to Tix-Cil may indicate relative effectiveness. Pre-exposure monoclonal antibody therapy may represent a strategy that will continue to offer clinical benefit for immunocompromised persons who are known to derive limited protection from vaccinations.


Subject(s)
COVID-19 , Organ Transplantation , Humans , COVID-19/prevention & control , SARS-CoV-2 , Antibodies, Monoclonal , Organ Transplantation/adverse effects , Transplant Recipients
13.
Clin Transplant ; 38(1): e15165, 2024 01.
Article in English | MEDLINE | ID: mdl-37837612

ABSTRACT

BACKGROUND: The use of bortezomib which is a proteasome inhibitor has been demonstrated to be efficacious in small number of patients as a desensitization strategy in heart transplant. We reviewed our single center's experience using Bortezomib along with plasmapheresis as desensitization therapy for highly sensitized patients to assess pre- and post-transplant outcomes. METHOD: We assessed 43 highly sensitized patients awaiting HTx (defined as cPRA > 50%) between 2010 and 2021 who underwent desensitization therapy with bortezomib. Only those patients who subsequently underwent HTx were included in this study. Enrolled patients received up to four doses of bortezomib (1.3 mg/m2 ) over 2 weeks in conjunction with plasmapheresis. The efficacy of PP/BTZ was assessed by comparing the calculated panel reactive antibodies to HLA class I or class II antigens. Post-transplant outcomes including overall survival and incidence of rejection were compared to those of non-sensitized patients (PRA < 10%, n = 649) from the same center. RESULTS: The average cPRA prior to PP/BTZ was 94.5%. Post-PP/BTZ there was no statistically significant decline in mean cPRA, class I cPRA, or class II cPRA, though the average percentage decrease in class I cPRA (8.7 ± 17.0%) was higher than the change in class II cPRA (4.4 ± 13.3%). Resulted were also replicated with C1q-binding antibodies showing more effect on I class compared to class II (15.0 ± 37.4% vs. 6.8 ± 33.6%) as well as with 1:8 dilutional assay (14.0 ± 23.0% vs. 9.1 ± 34.9%). Additionally, PP/BTZ treated patients and the control group of non-sensitized patients had similar overall 1 year survival (95.4 vs. 92.5%) but patients with PP/BTZ had increased incidence of AMR (79.1% vs. 97.1%, p = < .001), any treated rejection (62.8% vs. 86.7%, p = < .001) and de novo DSA development (81.4% vs. 92.5%, p = .007). Major side effects of PP/BTZ included thrombocytopenia (42%), infection requiring antibiotics (28%), and neuropathy (12%). CONCLUSION: The use of bortezomib in highly sensitized patients does not significantly lower circulating antibodies prior to heart transplantation. However, its use may improve the chances of obtaining an immuno-compatible donor heart and contribute to acceptable post-transplant outcomes.


Subject(s)
Heart Transplantation , Humans , Bortezomib/therapeutic use , Isoantibodies , Graft Rejection/drug therapy , Graft Rejection/etiology , Tissue Donors , HLA Antigens , Desensitization, Immunologic
14.
J Heart Lung Transplant ; 43(3): 387-393, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37802261

ABSTRACT

Primary graft dysfunction (PGD) is a leading cause of early morbidity and mortality following heart transplantation (HT). We sought to determine the association between pretransplant human leukocyte antigen (HLA) sensitization, as measured using the calculated panel reactive antibody (cPRA) value, and the risk of PGD. METHODS: Consecutive adult HT recipients (n = 596) from 1/2015 to 12/2019 at 2 US centers were included. Severity of PGD was based on the 2014 International Society for Heart and Lung Transplantation consensus statement. For each recipient, unacceptable HLA antigens were obtained and locus-specific cPRA (cPRA-LS) and pre-HT donor-specific antibodies (DSA) were assessed. RESULTS: Univariable logistic modeling showed that peak cPRA-LS for all loci and HLA-A was associated with increased severity of PGD as an ordinal variable (all loci: OR 1.78, 95% CI: 1.01-1.14, p = 0.025, HLA-A: OR 1.14, 95% CI: 1.03-1.26, p = 0.011). Multivariable analysis showed peak cPRA-LS for HLA-A, recipient beta-blocker use, total ischemic time, donor age, prior cardiac surgery, and United Network for Organ Sharing status 1 or 2 were associated with increased severity of PGD. The presence of DSA to HLA-B was associated with trend toward increased risk of mild-to-moderate PGD (OR 2.56, 95% CI: 0.99-6.63, p = 0.053), but DSA to other HLA loci was not associated with PGD. CONCLUSIONS: Sensitization for all HLA loci, and specifically HLA-A, is associated with an increased severity of PGD. These factors should be included in pre-HT risk stratification to minimize the risk of PGD.


Subject(s)
Heart Transplantation , Primary Graft Dysfunction , Adult , Humans , Primary Graft Dysfunction/epidemiology , Primary Graft Dysfunction/etiology , Heart Transplantation/adverse effects , HLA Antigens , Tissue Donors , Antibodies , HLA-A Antigens , Retrospective Studies
15.
J Heart Lung Transplant ; 43(2): 314-323, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37793509

ABSTRACT

BACKGROUND: Sensitization to human leukocyte antigens (HLA) is a persistent problem in heart transplant (HT) candidates. We sought to characterize the anti-HLA antibody and circulating B cell repertoire in a cohort of highly sensitized HT candidates. METHODS: We assessed immunoglobulin G (IgG) and immunoglobulin M (IgM) anti-HLA antibodies using Luminex single antigen bead assays in a cohort of 11 highly sensitized (HS; calculated panel reactive antibody ≥ 90%) and 3 mildly sensitized (MS) candidates. We also performed B cell receptor repertoire sequencing (BCRseq) in HS candidates and 33 non-candidate controls. HLA antibody strength was measured by mean fluorescence intensity (MFI). RESULTS: We found that IgM anti-HLA antibodies were present in all HS candidates, but with a lower breadth and strength as compared to IgG. When anti-HLA IgG specificities intersected with IgM, binding strength was higher. In contrast, there were IgM but no intersecting IgG specificities for the MS group. In four candidates in the HS group, IgG anti-HLA antibodies decreased in both breadth and strength after HT, but the decrease in strength was smaller if the IgG possessed a specificity that intersected with pre-transplant IgM. BCRseq revealed larger B cell clonotypes in HS candidates but similar diversity as compared to controls. CONCLUSIONS: IgM marks IgG anti-HLA antibodies with higher strength before HT and persistence after HT. The presence of IgM intersecting IgG for an anti-HLA specificity may be a useful approach to determine which donor HLA should be avoided for a sensitized candidate.


Subject(s)
Heart Transplantation , Immunoglobulin G , Humans , HLA Antigens , Histocompatibility Antigens Class I , Immunoglobulin M , Isoantibodies , Graft Rejection
17.
PLoS One ; 18(11): e0293293, 2023.
Article in English | MEDLINE | ID: mdl-37910454

ABSTRACT

BACKGROUND: The Kidney Failure Risk Equation (KFRE) and Kaiser Permanente Northwest (KPNW) models have been proposed to predict progression to ESKD among adults with CKD within 2 and 5 years. We evaluated the utility of these equations to predict the 1-year risk of ESKD in a contemporary, ethnically diverse CKD population. METHODS: We conducted a retrospective cohort study of adult members of Kaiser Permanente Northern California (KPNC) with CKD Stages 3-5 from January 2008-September 2015. We ascertained the onset of ESKD through September 2016, and calculated stage-specific estimates of model discrimination and calibration for the KFRE and KPNW equations. RESULTS: We identified 108,091 eligible adults with CKD (98,757 CKD Stage 3; 8,384 CKD Stage 4; and 950 CKD Stage 5 not yet receiving kidney replacement therapy), with mean age of 75 years, 55% women, and 37% being non-white. The overall 1-year risk of ESKD was 0.8% (95%CI: 0.8-0.9%). The KFRE displayed only moderate discrimination for CKD 3 and 5 (c = 0.76) but excellent discrimination for CKD 4 (c = 0.86), with good calibration for CKD 3-4 patients but suboptimal calibration for CKD 5. Calibration by CKD stage was similar to KFRE for the KPNW equation but displayed worse calibration across CKD stages for 1-year ESKD prediction. CONCLUSIONS: In a large, ethnically diverse, community-based CKD 3-5 population, both the KFRE and KPNW equation were suboptimal in accurately predicting the 1-year risk of ESKD within CKD stage 3 and 5, but more accurate for stage 4. Our findings suggest these equations can be used in1-year prediction for CKD 4 patients, but also highlight the need for more personalized, stage-specific equations that predicted various short- and long-term adverse outcomes to better inform overall decision-making.


Subject(s)
Kidney Failure, Chronic , Renal Insufficiency, Chronic , Adult , Humans , Female , Aged , Male , Disease Progression , Retrospective Studies , Kidney Failure, Chronic/epidemiology , Kidney Failure, Chronic/etiology , Renal Insufficiency, Chronic/epidemiology , Renal Replacement Therapy
18.
J Card Fail ; 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37907148

ABSTRACT

BACKGROUND: CARS (Cardiac Amyloidosis Registry Study) is a multicenter registry established in 2019 that includes patients with transthyretin (ATTR, wild-type and variant) and light chain (AL) cardiac amyloidosis (CA) evaluated at major amyloidosis centers between 1997 and 2025. CARS aims to describe the natural history of CA with attention to clinical and diagnostic variables at the time of diagnosis, real-world treatment patterns, and associated outcomes of patients in a diverse cohort that is more representative of the at-risk population than that described in CA clinical trials. METHODS AND RESULTS: This article describes the design and methodology of CARS, including procedures for data collection and preliminary results. As of February 2023, 20 centers in the United States enrolled 1415 patients, including 1155 (82%) with ATTR and 260 (18%) with AL CA. Among those with ATTR, wild-type is the most common ATTR (71%), and most of the 305 patients with variant ATTR have the p.V142I mutation (68%). A quarter of the total population identifies as Black. More individuals with AL are female (39%) compared to those with ATTR (13%). CONCLUSIONS: CARS will answer crucial clinical questions about CA natural history and permit comparison of different therapeutics not possible through current clinical trials. Future international collaboration will further strengthen the validity of observations of this increasingly recognized condition.

19.
BMC Oral Health ; 23(1): 686, 2023 09 22.
Article in English | MEDLINE | ID: mdl-37740190

ABSTRACT

BACKGROUND: Dental implants emerge as a dependable and efficacious alternative for patients experiencing partial or complete tooth loss. The stability of these implants is influenced by surface topography and macro-level design. In cases where the height of the maxillary posterior region is diminished, employing short implants can prove advantageous. With the aim of examining the distribution of von Mises stress, strain, and micromovement in D4 bone quality surrounding platform-switched short implants, measuring 6 mm in length and featuring diameters ranging from 4 to 6 mm, as well as different thread designs, an in-depth finite element analysis was conducted under immediate loading conditions. METHODOLOGY: A 3D finite element model was constructed to simulate maxillary molar crowns, incorporating an implant with a length of 6 mm and varying diameters and thread designs. The diameters utilized were 4/3.6 mm, 5/4 mm, and 6/4.8 mm, while the thread designs included buttress, square, and triangle patterns. Each model underwent analysis with a 100 N force applied in two directions: vertical and oblique, relative to the long axis of the implant. Stress, strain, and micromovement in the peri-implant region were recorded, employing the Ansys Workbench R v.18.1 software for modelling and analysis. RESULTS: When comparing all three diameters, the wide diameter (6 mm threads) exhibited the lowest values of peri-implant von Mises stresses (3.3 MPa and 35.1 MPa), strains (194 Ɛ and 484 Ɛ), and micromovements (0.7 µm and 1.3 Ɛ) subjected to axial and non-axial loading of a 100 N force. Notably, square microthreads yielded the most favorable stress parameters among the different thread shapes, manifesting the minimum values of stress, strains, and micromovements in their vicinity. CONCLUSION: For the treatment of atrophic ridges or in scenarios necessitating extensive surgical preparation of the implant site, a combination of short implants, wide diameters, and platform switching can be employed. In situations with reduced bone height and the requirement for an implant-supported prosthesis to replace a missing permanent maxillary molar, the utilization of wide-diameter platform-switched short implants measuring 6 mm in length, featuring a square thread design, should be taken into consideration.


Subject(s)
Dental Implants , Humans , Biomechanical Phenomena , Finite Element Analysis , Atrophy , Molar
20.
JACC Case Rep ; 19: 101935, 2023 Aug 02.
Article in English | MEDLINE | ID: mdl-37593594

ABSTRACT

Wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM) is more prevalent than appreciated in the elderly. We present the case of an 88-year-old woman who underwent heart transplantation for ischemic cardiomyopathy and then presented 21 years later with new onset atrial flutter, found on endomyocardial biopsy to have new ATTRwt-CM. (Level of Difficulty: Advanced.).

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