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1.
N Engl J Med ; 389(25): 2319-2330, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38015442

RESUMEN

BACKGROUND: Percutaneous coronary intervention (PCI) is frequently performed to reduce the symptoms of stable angina. Whether PCI relieves angina more than a placebo procedure in patients who are not receiving antianginal medication remains unknown. METHODS: We conducted a double-blind, randomized, placebo-controlled trial of PCI in patients with stable angina. Patients stopped all antianginal medications and underwent a 2-week symptom assessment phase before randomization. Patients were then randomly assigned in a 1:1 ratio to undergo PCI or a placebo procedure and were followed for 12 weeks. The primary end point was the angina symptom score, which was calculated daily on the basis of the number of angina episodes that occurred on a given day, the number of antianginal medications prescribed on that day, and clinical events, including the occurrence of unblinding owing to unacceptable angina or acute coronary syndrome or death. Scores range from 0 to 79, with higher scores indicating worse health status with respect to angina. RESULTS: A total of 301 patients underwent randomization: 151 to the PCI group and 150 to the placebo group. The mean (±SD) age was 64±9 years, and 79% were men. Ischemia was present in one cardiac territory in 242 patients (80%), in two territories in 52 patients (17%), and in three territories in 7 patients (2%). In the target vessels, the median fractional flow reserve was 0.63 (interquartile range, 0.49 to 0.75), and the median instantaneous wave-free ratio was 0.78 (interquartile range, 0.55 to 0.87). At the 12-week follow-up, the mean angina symptom score was 2.9 in the PCI group and 5.6 in the placebo group (odds ratio, 2.21; 95% confidence interval, 1.41 to 3.47; P<0.001). One patient in the placebo group had unacceptable angina leading to unblinding. Acute coronary syndromes occurred in 4 patients in the PCI group and in 6 patients in the placebo group. CONCLUSIONS: Among patients with stable angina who were receiving little or no antianginal medication and had objective evidence of ischemia, PCI resulted in a lower angina symptom score than a placebo procedure, indicating a better health status with respect to angina. (Funded by the National Institute for Health and Care Research Imperial Biomedical Research Centre and others; ORBITA-2 ClinicalTrials.gov number, NCT03742050.).


Asunto(s)
Angina Estable , Intervención Coronaria Percutánea , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndrome Coronario Agudo , Angina Estable/tratamiento farmacológico , Angina Estable/cirugía , Fármacos Cardiovasculares/uso terapéutico , Reserva del Flujo Fraccional Miocárdico , Estado de Salud , Intervención Coronaria Percutánea/métodos , Resultado del Tratamiento , Método Doble Ciego , Isquemia Miocárdica
2.
Circulation ; 2024 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-39462291

RESUMEN

BACKGROUND: The Placebo-controlled Trial of Percutaneous Coronary Intervention for the Relief of Stable Angina (ORBITA-2) provided evidence for the role of percutaneous coronary intervention (PCI) for angina relief in stable coronary artery disease (CAD). Fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) are often used to guide PCI, however their ability to predict placebo-controlled angina improvement is unknown. METHODS: Participants with angina, ischemia, and stable CAD were enrolled and antianginal medications were stopped. Participants reported angina episodes daily for 2 weeks using the ORBITA-app. At the research angiogram, FFR and iFR were measured. After sedation and auditory isolation, participants were randomized to PCI or placebo, before entering a 12-week blinded follow-up phase with daily angina reporting. The ability of FFR and iFR, analyzed as continuous variables, to predict the placebo-controlled effect of PCI, was tested using Bayesian proportional odds modelling. RESULTS: Invasive physiology data were available in 279 patients (140 PCI and 139 placebo). The median (IQR) age was 65 years (59.0 to 70.5) and 223 (79.9%) were male. Median FFR was 0.60 (0.46 to 0.73) and median iFR was 0.76 (0.50 to 0.86). The lower the FFR or iFR, the greater the placebo-controlled improvement with PCI across all endpoints. There was strong evidence that a patient with an FFR at the lower quartile would have a greater placebo-controlled improvement in angina symptom score with PCI than a patient at the upper quartile (FFR 0.46 vs. 0.73: OR 2.01, 95% CrI 1.79 to 2.26, Pr(Interaction)>99.9%). Similarly, there was strong evidence that a patient with an iFR at the lower quartile would have a greater placebo controlled improvement in angina symptom score with PCI than a patient with an iFR at the upper quartile (iFR 0.50 vs. 0.86: OR 2.13, 95% CrI 1.87 to 2.45, Pr(Interaction) >99.9%). The relationship between benefit and physiology was seen in both Rose angina and Rose nonangina. CONCLUSIONS: Physiological stenosis severity, as measured by FFR and iFR, predicts placebo-controlled angina relief from PCI. Invasive coronary physiology can be used to target PCI to those patients who are most likely to experience benefit.

3.
Lancet ; 403(10436): 1543-1553, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38604209

RESUMEN

BACKGROUND: The coronary sinus reducer (CSR) is proposed to reduce angina in patients with stable coronary artery disease by improving myocardial perfusion. We aimed to measure its efficacy, compared with placebo, on myocardial ischaemia reduction and symptom improvement. METHODS: ORBITA-COSMIC was a double-blind, randomised, placebo-controlled trial conducted at six UK hospitals. Patients aged 18 years or older with angina, stable coronary artery disease, ischaemia, and no further options for treatment were eligible. All patients completed a quantitative adenosine-stress perfusion cardiac magnetic resonance scan, symptom and quality-of-life questionnaires, and a treadmill exercise test before entering a 2-week symptom assessment phase, in which patients reported their angina symptoms using a smartphone application (ORBITA-app). Patients were randomly assigned (1:1) to receive either CSR or placebo. Both participants and investigators were masked to study assignment. After the CSR implantation or placebo procedure, patients entered a 6-month blinded follow-up phase in which they reported their daily symptoms in the ORBITA-app. At 6 months, all assessments were repeated. The primary outcome was myocardial blood flow in segments designated ischaemic at enrolment during the adenosine-stress perfusion cardiac magnetic resonance scan. The primary symptom outcome was the number of daily angina episodes. Analysis was done by intention-to-treat and followed Bayesian methodology. The study is registered with ClinicalTrials.gov, NCT04892537, and completed. FINDINGS: Between May 26, 2021, and June 28, 2023, 61 patients were enrolled, of whom 51 (44 [86%] male; seven [14%] female) were randomly assigned to either the CSR group (n=25) or the placebo group (n=26). Of these, 50 patients were included in the intention-to-treat analysis (24 in the CSR group and 26 in the placebo group). 454 (57%) of 800 imaged cardiac segments were ischaemic at enrolment, with a median stress myocardial blood flow of 1·08 mL/min per g (IQR 0·77-1·41). Myocardial blood flow in ischaemic segments did not improve with CSR compared with placebo (difference 0·06 mL/min per g [95% CrI -0·09 to 0·20]; Pr(Benefit)=78·8%). The number of daily angina episodes was reduced with CSR compared with placebo (OR 1·40 [95% CrI 1·08 to 1·83]; Pr(Benefit)=99·4%). There were two CSR embolisation events in the CSR group, and no acute coronary syndrome events or deaths in either group. INTERPRETATION: ORBITA-COSMIC found no evidence that the CSR improved transmural myocardial perfusion, but the CSR did improve angina compared with placebo. These findings provide evidence for the use of CSR as a further antianginal option for patients with stable coronary artery disease. FUNDING: Medical Research Council, Imperial College Healthcare Charity, National Institute for Health and Care Research Imperial Biomedical Research Centre, St Mary's Coronary Flow Trust, British Heart Foundation.


Asunto(s)
Angina Estable , Enfermedad de la Arteria Coronaria , Seno Coronario , Intervención Coronaria Percutánea , Humanos , Masculino , Femenino , Enfermedad de la Arteria Coronaria/terapia , Angina Estable/tratamiento farmacológico , Seno Coronario/diagnóstico por imagen , Teorema de Bayes , Resultado del Tratamiento , Intervención Coronaria Percutánea/efectos adversos , Método Doble Ciego , Isquemia , Adenosina
4.
FASEB J ; 38(1): e23377, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38133902

RESUMEN

The roles of anti-Müllerian hormone (AMH) continue to expand, from its discovery as a critical factor in sex determination, through its identification as a regulator of ovarian folliculogenesis, its use in fertility clinics as a measure of ovarian reserve, and its emerging role in hypothalamic-pituitary function. In light of these actions, AMH is considered an attractive therapeutic target to address diverse reproductive needs, including fertility preservation. Here, we set out to characterize the molecular mechanisms that govern AMH synthesis and activity. First, we enhanced the processing of the AMH precursor to >90% by introducing more efficient proprotein convertase cleavage sites (RKKR or ISSRKKRSVSS [SCUT]). Importantly, enhanced processing corresponded with a dramatic increase in secreted AMH activity. Next, based on species differences across the AMH type II receptor-binding interface, we generated a series of human AMH variants and assessed bioactivity. AMHSCUT potency (EC50 4 ng/mL) was increased 5- or 10-fold by incorporating Gln484 Met/Leu535 Thr (EC50 0.8 ng/mL) or Gln484 Met/Gly533 Ser (EC50 0.4 ng/mL) mutations, respectively. Furthermore, the Gln484 Met/Leu535 Thr double mutant displayed enhanced efficacy, relative to AMHSCUT . Finally, we identified residues within the wrist pre-helix of AMH (Trp494 , Gln496 , Ser497 , and Asp498 ) that likely mediate type I receptor binding. Mutagenesis of these residues generated gain- (Trp494 Phe or Gln496 Leu) or loss- (Ser497 Ala) of function AMH variants. Surprisingly, combining activating type I and type II receptor mutations only led to modest additive increases in AMH potency/efficacy. Our study is the first to characterize AMH residues involved in type I receptor binding and suggests a step-wise receptor-complex assembly mechanism, in which enhancement in the affinity of the ligand for either receptor can increase AMH activity beyond the natural level.


Asunto(s)
Hormona Antimülleriana , Hormonas Peptídicas , Femenino , Humanos , Hormona Antimülleriana/genética , Ovario , Secuencia de Aminoácidos , Fragmentos de Péptidos
5.
Biochem J ; 481(7): 547-564, 2024 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-38533769

RESUMEN

Activins are one of the three distinct subclasses within the greater Transforming growth factor ß (TGFß) superfamily. First discovered for their critical roles in reproductive biology, activins have since been shown to alter cellular differentiation and proliferation. At present, members of the activin subclass include activin A (ActA), ActB, ActC, ActE, and the more distant members myostatin and GDF11. While the biological roles and signaling mechanisms of most activins class members have been well-studied, the signaling potential of ActE has remained largely unknown. Here, we characterized the signaling capacity of homodimeric ActE. Molecular modeling of the ligand:receptor complexes showed that ActC and ActE shared high similarity in both the type I and type II receptor binding epitopes. ActE signaled specifically through ALK7, utilized the canonical activin type II receptors, ActRIIA and ActRIIB, and was resistant to the extracellular antagonists follistatin and WFIKKN. In mature murine adipocytes, ActE invoked a SMAD2/3 response via ALK7, like ActC. Collectively, our results establish ActE as a specific signaling ligand which activates the type I receptor, ALK7.


Asunto(s)
Proteínas Portadoras , Factor de Crecimiento Transformador beta , Ratones , Animales , Factor de Crecimiento Transformador beta/metabolismo , Ligandos , Receptores de Activinas/genética , Receptores de Activinas/metabolismo , Activinas/metabolismo
6.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35058362

RESUMEN

Immune cells infiltrate the peripheral nervous system (PNS) after injury and with autoimmunity, but their net effect is divergent. After injury, immune cells are reparative, while in inflammatory neuropathies (e.g., Guillain Barré Syndrome and chronic inflammatory demyelinating polyneuropathy), immune cells are proinflammatory and promote autoimmune demyelination. An understanding of immune cell phenotypes that distinguish these conditions may, therefore, reveal new therapeutic targets for switching immune cells from an inflammatory role to a reparative state. In an autoimmune regulator (Aire)-deficient mouse model of inflammatory neuropathy, we used single-cell RNA sequencing of sciatic nerves to discover a transcriptionally heterogeneous cellular landscape, including multiple myeloid, innate lymphoid, and lymphoid cell types. Analysis of cell-cell ligand-receptor interactions uncovered a macrophage-mediated tumor necrosis factor-α (TNF-α) signaling axis that is induced by interferon-γ and required for initiation of autoimmune demyelination. Developmental trajectory visualization suggested that TNF-α signaling is associated with metabolic reprogramming of macrophages and polarization of macrophages from a reparative state in injury to a pathogenic, inflammatory state in autoimmunity. Autocrine TNF-α signaling induced macrophage expression of multiple genes (Clec4e, Marcksl1, Cxcl1, and Cxcl10) important in immune cell activation and recruitment. Genetic and antibody-based blockade of TNF-α/TNF-α signaling ameliorated clinical neuropathy, peripheral nerve infiltration, and demyelination, which provides preclinical evidence that the TNF-α axis may be effectively targeted to resolve inflammatory neuropathies.


Asunto(s)
Enfermedades Neuroinflamatorias/etiología , Enfermedades Neuroinflamatorias/metabolismo , Enfermedades del Sistema Nervioso Periférico/etiología , Enfermedades del Sistema Nervioso Periférico/metabolismo , Poliendocrinopatías Autoinmunes/complicaciones , Factor de Necrosis Tumoral alfa/metabolismo , Traslado Adoptivo , Animales , Anticuerpos Monoclonales/farmacología , Comunicación Autocrina , Biomarcadores , Citocinas/metabolismo , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Perfilación de la Expresión Génica , Mediadores de Inflamación/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Ratones Transgénicos , Enfermedades Neuroinflamatorias/tratamiento farmacológico , Enfermedades Neuroinflamatorias/patología , Comunicación Paracrina , Enfermedades del Sistema Nervioso Periférico/tratamiento farmacológico , Enfermedades del Sistema Nervioso Periférico/patología , Poliendocrinopatías Autoinmunes/genética , Receptores del Factor de Necrosis Tumoral/deficiencia , Nervio Ciático/inmunología , Nervio Ciático/metabolismo , Nervio Ciático/patología , Transducción de Señal , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
7.
J Am Chem Soc ; 146(39): 26609-26615, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39288263

RESUMEN

Despite the prevalence of N-heteroarenes in small-molecule pharmaceuticals, Pd-catalyzed C-N cross-coupling reactions of aryl halides and amines containing these rings remain challenging due to their ability to displace the supporting ligand via coordination to the metal center. To address this limitation, we report the development of a highly robust Pd catalyst supported by a new dialkylbiarylphosphine ligand, FPhos. The FPhos-supported catalyst effectively resists N-heteroarene-mediated catalyst deactivation to readily promote C-N coupling between a wide variety of Lewis-basic aryl halides and secondary amines, including densely functionalized pharmaceuticals. Mechanistic and structural investigations, as well as principal component analysis and density functional theory, elucidated two key design features that enable FPhos to overcome the limitations of previous ligands. First, the ligated Pd complex is stabilized through its conformational preference for the O-bound isomer, which likely resists coordination by N-heteroarenes. Second, 3',5'-disubstitution on the non-phosphorus-containing ring of FPhos creates the ideal steric environment around the Pd center, which facilitates binding by larger secondary amines while mitigating the formation of off-cycle palladacycle species.

8.
J Med Virol ; 96(8): e29791, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39092792

RESUMEN

In mid-2022, New York City (NYC) became the epicenter of the US mpox outbreak. We provided real-time mpox case forecasts to the NYC Department of Health and Mental Hygiene to aid in outbreak response. Forecasting methodologies evolved as the epidemic progressed. Initially, lacking knowledge of at-risk population size, we used exponential growth models to forecast cases. Once exponential growth slowed, we used a Susceptible-Exposed-Infectious-Recovered (SEIR) model. Retrospectively, we explored if forecasts could have been improved using an SEIR model in place of our early exponential growth model, with or without knowing the case detection rate. Early forecasts from exponential growth models performed poorly, as 2-week mean absolute error (MAE) grew from 53 cases/week (July 1-14) to 457 cases/week (July 15-28). However, when exponential growth slowed, providing insight into susceptible population size, an SEIR model was able to accurately predict the remainder of the outbreak (7-week MAE: 13.4 cases/week). Retrospectively, we found there was not enough known about the epidemiological characteristics of the outbreak to parameterize an SEIR model early on. However, if the at-risk population and case detection rate were known, an SEIR model could have improved accuracy over exponential growth models early in the outbreak.


Asunto(s)
Brotes de Enfermedades , Predicción , Mpox , Ciudad de Nueva York/epidemiología , Humanos , Predicción/métodos , Estudios Retrospectivos , Mpox/epidemiología , Modelos Teóricos , Modelos Estadísticos
9.
Muscle Nerve ; 69(5): 556-565, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38380691

RESUMEN

INTRODUCTION/AIMS: The CHAMPION MG study demonstrated that ravulizumab significantly improved Myasthenia Gravis-Activities of Daily Living (MG-ADL) and Quantitative Myasthenia Gravis (QMG) total scores versus placebo in adults with acetylcholine receptor antibody-positive generalized myasthenia gravis (AChR+ gMG). This post hoc analysis aimed to assess these outcomes by time from MG diagnosis. METHODS: Changes from baseline to week 26 in MG-ADL and QMG total scores were analyzed by time from MG diagnosis to study entry (≤2 vs. >2 years). Within each subgroup, least-squares (LS) mean changes for ravulizumab and placebo were compared using mixed models for repeated measures. RESULTS: In ravulizumab-treated patients, differences in LS mean (standard error of the mean) changes from baseline to week 26 were not statistically significant in the ≤2-years subgroup versus the >2-years subgroup for MG-ADL (-4.3 [0.70] vs. -2.9 [0.37]; p = .0511) or QMG (-4.3 [0.94] vs. -2.5 [0.50]; p = .0822) scores. No clear trends were observed in the placebo group. LS mean changes from baseline were significantly greater for ravulizumab versus placebo in both the ≤2 and >2 years from diagnosis subgroups for MG-ADL and QMG scores (all p < .05). The difference in treatment effect between the ≤2-years and >2-years subgroups was not statistically significant. No clinically meaningful between-subgroup differences in treatment-emergent adverse events were observed in ravulizumab-treated patients. DISCUSSION: Ravulizumab treatment improved clinical outcomes for patients with AChR+ gMG regardless of time from diagnosis. A numerical trend was observed favoring greater treatment effect with earlier versus later treatment after diagnosis. Further studies are required for confirmation.


Asunto(s)
Actividades Cotidianas , Miastenia Gravis , Adulto , Humanos , Miastenia Gravis/diagnóstico , Miastenia Gravis/tratamiento farmacológico , Receptores Colinérgicos , Anticuerpos Monoclonales Humanizados/uso terapéutico
10.
Eur J Neurol ; : e16490, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39373062

RESUMEN

BACKGROUND AND PURPOSE: The efficacy and safety of ravulizumab, a terminal complement C5 inhibitor, in adults with anti-acetylcholine receptor antibody-positive (AChR Ab+) generalized myasthenia gravis (gMG) were demonstrated in the CHAMPION MG study (NCT03920293). This analysis aimed to characterize the latency to onset of a clinically meaningful therapeutic effect for ravulizumab. METHODS: Post hoc analysis of data collected for up to 60 weeks from CHAMPION MG was performed to assess the timing of response to ravulizumab. Response was analyzed based on reductions of ≥2 and ≥3 points (minimal clinically important differences [MCIDs]) in Myasthenia Gravis-Activities of Daily Living (MG-ADL) and Quantitative Myasthenia Gravis (QMG) total scores, respectively, and on more rigorous reductions of ≥3 and ≥5 points, respectively. Time to first response was assessed using the Kaplan-Meier product-limit method. RESULTS: The median (95% confidence interval) time to first response was 2.1 (2.1-2.6) and 4.1 (2.3-10.0) weeks for reductions of ≥2 and ≥3 points in MG-ADL total score, respectively (n = 139), and 4.1 (2.1-10.0) and 18.3 (11.0-33.4) weeks for reductions of ≥3 and ≥5 points in QMG total score, respectively (n = 134). Cumulative response rates at Week 60 (data cut-off) were 88% and 82% for ≥2- and ≥3-point MG-ADL score reductions, respectively, and 86% and 59% for ≥3- and ≥5-point QMG score reductions, respectively. CONCLUSIONS: The median times to MCID with ravulizumab treatment in patients with AChR Ab+ gMG were ~2 weeks and ~4 weeks based on MCID MG-ADL and QMG total score reductions, respectively.

11.
Eur J Neurol ; 31(1): e16098, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37843174

RESUMEN

BACKGROUND AND PURPOSE: Generalized myasthenia gravis (gMG) is a rare, chronic, neuromuscular autoimmune disease mediated by pathogenic immunoglobulin G (IgG) autoantibodies. Patients with gMG experience debilitating muscle weakness, resulting in impaired mobility, speech, swallowing, vision and respiratory function. Efgartigimod is a human IgG1 antibody Fc fragment engineered for increased binding affinity to neonatal Fc receptor. The neonatal Fc receptor blockade by efgartigimod competitively inhibits endogenous IgG binding, leading to decreased IgG recycling and increased degradation resulting in lower IgG concentration. METHODS: The safety and efficacy of efgartigimod were evaluated in the ADAPT study. Key efficacy outcome measures included Myasthenia Gravis Activities of Daily Living (MG-ADL) and Quantitative Myasthenia Gravis (QMG) scores. Efgartigimod demonstrated significant improvement in both the MG-ADL and QMG scores. This post hoc analysis aimed to determine whether all subdomains of MG-ADL and QMG improved with efgartigimod treatment. Individual items of MG-ADL and QMG were grouped into four subdomains: bulbar, ocular, limb/gross motor and respiratory. Change from baseline over 10 weeks in each subdomain was calculated for each group. RESULTS: Greater improvements from baseline were seen across MG-ADL subdomains in participants treated with efgartigimod compared with placebo. These improvements were typically observed 1 to 2 weeks after the first infusion and correlated with reductions in IgG. Similar results were observed across most QMG subdomains. CONCLUSIONS: These post hoc analyses of MG-ADL and QMG subdomain data from ADAPT suggest that efgartigimod is beneficial in improving muscle function and strength across all muscle groups, leading to the observed efficacy in participants with gMG.


Asunto(s)
Actividades Cotidianas , Miastenia Gravis , Recién Nacido , Humanos , Miastenia Gravis/tratamiento farmacológico , Fragmentos Fc de Inmunoglobulinas/uso terapéutico , Inmunoglobulina G , Músculos
12.
J Cardiovasc Magn Reson ; 26(2): 101067, 2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39079601

RESUMEN

BACKGROUND: Accurate measurements from cardiovascular magnetic resonance (CMR) images require precise positioning of scan planes and elimination of motion artifacts from arrhythmia or breathing. Unidentified or incorrectly managed artifacts degrade image quality, invalidate clinical measurements, and decrease diagnostic confidence. Currently, radiographers must manually inspect each acquired image to confirm diagnostic quality and decide whether reacquisition or a change in sequences is warranted. We aimed to develop artificial intelligence (AI) to provide continuous quality scores across different quality domains, and from these, determine whether cines are clinically adequate, require replanning, or warrant a change in protocol. METHODS: A three-dimensional convolutional neural network was trained to predict cine quality graded on a continuous scale by a level 3 CMR expert, focusing separately on planning and motion artifacts. It incorporated four distinct output heads for the assessment of image quality in terms of (a, b, c) 2-, 3- and 4-chamber misplanning, and (d) long- and short-axis arrhythmia/breathing artifact. Backpropagation was selectively performed across these heads based on the labels present for each cine. Each image in the testing set was reported by four level 3 CMR experts, providing a consensus on clinical adequacy. The AI's assessment of image quality and ability to identify images requiring replanning or sequence changes were evaluated with Spearman's rho and the area under receiver operating characteristic curve (AUROC), respectively. RESULTS: A total of 1940 cines across 1387 studies were included. On the test set of 383 cines, AI-judged image quality correlated strongly with expert judgment, with Spearman's rho of 0.84, 0.84, 0.81, and 0.81 for 2-, 3- and 4-chamber planning quality and the extent of arrhythmia or breathing artifacts, respectively. The AI also showed high efficacy in flagging clinically inadequate cines (AUROC 0.88, 0.93, and 0.93 for identifying misplanning of 2-, 3- and 4-chamber cines, and 0.90 for identifying movement artifacts). CONCLUSION: AI can assess distinct domains of CMR cine quality and provide continuous quality scores that correlate closely with a consensus of experts. These ratings could be used to identify cases where reacquisition is warranted and guide corrective actions to optimize image quality, including replanning, prospective gating, or real-time imaging.

13.
J Cardiovasc Magn Reson ; 26(1): 100005, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38211656

RESUMEN

BACKGROUND: Cardiovascular magnetic resonance (CMR) imaging is an important tool for evaluating the severity of aortic stenosis (AS), co-existing aortic disease, and concurrent myocardial abnormalities. Acquiring this additional information requires protocol adaptations and additional scanner time, but is not necessary for the majority of patients who do not have AS. We observed that the relative signal intensity of blood in the ascending aorta on a balanced steady state free precession (bSSFP) 3-chamber cine was often reduced in those with significant aortic stenosis. We investigated whether this effect could be quantified and used to predict AS severity in comparison to existing gold-standard measurements. METHODS: Multi-centre, multi-vendor retrospective analysis of patients with AS undergoing CMR and transthoracic echocardiography (TTE). Blood signal intensity was measured in a ∼1 cm2 region of interest (ROI) in the aorta and left ventricle (LV) in the 3-chamber bSSFP cine. Because signal intensity varied across patients and scanner vendors, a ratio of the mean signal intensity in the aorta ROI to the LV ROI (Ao:LV) was used. This ratio was compared using Pearson correlations against TTE parameters of AS severity: aortic valve peak velocity, mean pressure gradient and the dimensionless index. The study also assessed whether field strength (1.5 T vs. 3 T) and patient characteristics (presence of bicuspid aortic valves (BAV), dilated aortic root and low flow states) altered this signal relationship. RESULTS: 314 patients (median age 69 [IQR 57-77], 64% male) who had undergone both CMR and TTE were studied; 84 had severe AS, 78 had moderate AS, 66 had mild AS and 86 without AS were studied as a comparator group. The median time between CMR and TTE was 12 weeks (IQR 4-26). The Ao:LV ratio at 1.5 T strongly correlated with peak velocity (r = -0.796, p = 0.001), peak gradient (r = -0.772, p = 0.001) and dimensionless index (r = 0.743, p = 0.001). An Ao:LV ratio of < 0.86 was 84% sensitive and 82% specific for detecting AS of any severity and a ratio of 0.58 was 83% sensitive and 92% specific for severe AS. The ability of Ao:LV ratio to predict AS severity remained for patients with bicuspid aortic valves, dilated aortic root or low indexed stroke volume. The relationship between Ao:LV ratio and AS severity was weaker at 3 T. CONCLUSIONS: The Ao:LV ratio, derived from bSSFP 3-chamber cine images, shows a good correlation with existing measures of AS severity. It demonstrates utility at 1.5 T and offers an easily calculable metric that can be used at the time of scanning or automated to identify on an adaptive basis which patients benefit from dedicated imaging to assess which patients should have additional sequences to assess AS.


Asunto(s)
Estenosis de la Válvula Aórtica , Válvula Aórtica , Imagen por Resonancia Cinemagnética , Valor Predictivo de las Pruebas , Índice de Severidad de la Enfermedad , Función Ventricular Izquierda , Humanos , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/fisiopatología , Femenino , Masculino , Estudios Retrospectivos , Anciano , Persona de Mediana Edad , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/fisiopatología , Válvula Aórtica/patología , Válvula Aórtica/anomalías , Reproducibilidad de los Resultados , Aorta/diagnóstico por imagen , Aorta/fisiopatología , Interpretación de Imagen Asistida por Computador , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Flujo Sanguíneo Regional , Estados Unidos
14.
J Cardiovasc Magn Reson ; 26(1): 101040, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38522522

RESUMEN

BACKGROUND: Late gadolinium enhancement (LGE) of the myocardium has significant diagnostic and prognostic implications, with even small areas of enhancement being important. Distinguishing between definitely normal and definitely abnormal LGE images is usually straightforward, but diagnostic uncertainty arises when reporters are not sure whether the observed LGE is genuine or not. This uncertainty might be resolved by repetition (to remove artifact) or further acquisition of intersecting images, but this must take place before the scan finishes. Real-time quality assurance by humans is a complex task requiring training and experience, so being able to identify which images have an intermediate likelihood of LGE while the scan is ongoing, without the presence of an expert is of high value. This decision-support could prompt immediate image optimization or acquisition of supplementary images to confirm or refute the presence of genuine LGE. This could reduce ambiguity in reports. METHODS: Short-axis, phase-sensitive inversion recovery late gadolinium images were extracted from our clinical cardiac magnetic resonance (CMR) database and shuffled. Two, independent, blinded experts scored each individual slice for "LGE likelihood" on a visual analog scale, from 0 (absolute certainty of no LGE) to 100 (absolute certainty of LGE), with 50 representing clinical equipoise. The scored images were split into two classes-either "high certainty" of whether LGE was present or not, or "low certainty." The dataset was split into training, validation, and test sets (70:15:15). A deep learning binary classifier based on the EfficientNetV2 convolutional neural network architecture was trained to distinguish between these categories. Classifier performance on the test set was evaluated by calculating the accuracy, precision, recall, F1-score, and area under the receiver operating characteristics curve (ROC AUC). Performance was also evaluated on an external test set of images from a different center. RESULTS: One thousand six hundred and forty-five images (from 272 patients) were labeled and split at the patient level into training (1151 images), validation (247 images), and test (247 images) sets for the deep learning binary classifier. Of these, 1208 images were "high certainty" (255 for LGE, 953 for no LGE), and 437 were "low certainty". An external test comprising 247 images from 41 patients from another center was also employed. After 100 epochs, the performance on the internal test set was accuracy = 0.94, recall = 0.80, precision = 0.97, F1-score = 0.87, and ROC AUC = 0.94. The classifier also performed robustly on the external test set (accuracy = 0.91, recall = 0.73, precision = 0.93, F1-score = 0.82, and ROC AUC = 0.91). These results were benchmarked against a reference inter-expert accuracy of 0.86. CONCLUSION: Deep learning shows potential to automate quality control of late gadolinium imaging in CMR. The ability to identify short-axis images with intermediate LGE likelihood in real-time may serve as a useful decision-support tool. This approach has the potential to guide immediate further imaging while the patient is still in the scanner, thereby reducing the frequency of recalls and inconclusive reports due to diagnostic indecision.


Asunto(s)
Medios de Contraste , Aprendizaje Profundo , Interpretación de Imagen Asistida por Computador , Valor Predictivo de las Pruebas , Humanos , Medios de Contraste/administración & dosificación , Reproducibilidad de los Resultados , Interpretación de Imagen Asistida por Computador/normas , Bases de Datos Factuales , Miocardio/patología , Masculino , Femenino , Imagen por Resonancia Cinemagnética/normas , Persona de Mediana Edad , Cardiopatías/diagnóstico por imagen , Garantía de la Calidad de Atención de Salud/normas , Variaciones Dependientes del Observador , Anciano , Imagen por Resonancia Magnética/normas
15.
Eur Heart J ; 44(10): 836-852, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36660821

RESUMEN

AIMS: Additional randomized clinical trial (RCT) data comparing transcatheter aortic valve implantation (TAVI) with surgical aortic valve replacement (SAVR) is available, including longer term follow-up. A meta-analysis comparing TAVI to SAVR was performed. A pragmatic risk classification was applied, partitioning lower-risk and higher-risk patients. METHODS AND RESULTS: The main endpoints were death, strokes, and the composite of death or disabling stroke, occurring at 1 year (early) or after 1 year (later). A random-effects meta-analysis was performed. Eight RCTs with 8698 patients were included. In lower-risk patients, at 1 year, the risk of death was lower after TAVI compared with SAVR [relative risk (RR) 0.67; 95% confidence interval (CI) 0.47 to 0.96, P = 0.031], as was death or disabling stroke (RR 0.68; 95% CI 0.50 to 0.92, P = 0.014). There were no differences in strokes. After 1 year, in lower-risk patients, there were no significant differences in all main outcomes. In higher-risk patients, there were no significant differences in main outcomes. New-onset atrial fibrillation, major bleeding, and acute kidney injury occurred less after TAVI; new pacemakers, vascular complications, and paravalvular leak occurred more after TAVI. CONCLUSION: In lower-risk patients, there was an early mortality reduction with TAVI, but no differences after later follow-up. There was also an early reduction in the composite of death or disabling stroke, with no difference at later follow-up. There were no significant differences for higher-risk patients. Informed therapy decisions may be more dependent on the temporality of events or secondary endpoints than the long-term occurrence of main clinical outcomes.


Asunto(s)
Estenosis de la Válvula Aórtica , Implantación de Prótesis de Válvulas Cardíacas , Accidente Cerebrovascular , Humanos , Válvula Aórtica/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología
16.
J Arthroplasty ; 39(9S1): S67-S72, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38830433

RESUMEN

BACKGROUND: The aim of the study was to analyze the Canadian Cardiovascular Society (CCS) guidelines for routine postoperative troponin testing after elective total hip arthroplasty (THA) to reduce the mortality rate resulting from myocardial injury. The purpose of this study was to assess the prognostic relevance of implementing these guidelines to minimize cardiac events in patients undergoing elective THA. METHODS: Patients who underwent THA surgery in 2020 were included in the study. The inclusion criteria were elective THA patients aged ≥45 years, while emergency, revision, and simultaneous bilateral THA surgeries were excluded. The patients were categorized into 4 groups based on the CCS guidelines. RESULTS: The study included 669 patients who had an average age of 67 years. There were 43 patients (6.4%), who experienced a rise in troponin levels ≥30 ng/L and developed myocardial injury after noncardiac surgery. Among these patients, 8 developed cardiac complications, and one experienced a serious cardiac event that resulted in death. Notably, there was a significant increase in the length of hospital stay for patients who received the postoperative screening protocol. CONCLUSIONS: The implementation of the CCS guidelines for routine postoperative troponin testing in elective THA surgery did not significantly decrease the rate of cardiac events or mortality.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Complicaciones Posoperatorias , Humanos , Artroplastia de Reemplazo de Cadera/efectos adversos , Anciano , Masculino , Femenino , Persona de Mediana Edad , Canadá/epidemiología , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Troponina/sangre , Guías de Práctica Clínica como Asunto , Procedimientos Quirúrgicos Electivos/efectos adversos , Estudios Retrospectivos
17.
J Arthroplasty ; 39(9S1): S51-S54, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38830428

RESUMEN

BACKGROUND: The incidence of total joint arthroplasty is increasing, with added emphasis on shifting care toward outpatient surgery. This has demonstrated improvements in costs and care; however, safety must be prioritized. Published assessment tools highlight candidates for outpatient surgery; however, they often do not define patients who have a worse prognosis. Limited healthcare resources occasionally force patients to convert to outpatient surgery or risk cancellation, creating a dilemma for both patients and surgeons. We evaluated the short-term (90-day) outcomes of patients converted from planned inpatient admission to same-day discharge on day of surgery outpatients and sought to identify any groups at risk, who may not be appropriate for this conversion. METHODS: We identified all patients undergoing planned inpatient total hip or knee arthroplasty at a tertiary academic medical center over a 2-year period. We included patients discharged the day of surgery for analysis, excluding revision procedures and those performed for fracture care. A manual chart review identified demographic factors and primary outcome measures; including reoperation, readmission, and emergency room visits within a 90-day postoperative period. RESULTS: We identified a total of 80 patients who converted from inpatient to outpatient surgery over a 2-year interval. Over the first 90 days postoperatively 4 (5%) patients were readmitted: 2 (2.5%) for medical complications and 2 (2.5%) for reoperation. There were 2 (2.5%) reoperations; one (1.25%) for manipulation under anesthesia, and one (1.25%) for periprosthetic joint infection. There were 5 (6.3%) wound complications; however, only one (1.25%) required surgical intervention. A total of 5 (6.3%) patients returned to an emergency department, leading to a single (1.25%) hospital readmission. CONCLUSIONS: Hospital and healthcare resources are occasionally limited to the extent that patients must convert to outpatient surgery or risk cancellation. At our institution, the same-day conversion of planned inpatient hip and knee arthroplasty patients to outpatient surgery was safe and did not increase short-term clinical outcomes or complications.


Asunto(s)
Procedimientos Quirúrgicos Ambulatorios , Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Readmisión del Paciente , Humanos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Readmisión del Paciente/estadística & datos numéricos , Resultado del Tratamiento , Reoperación/estadística & datos numéricos , Estudios Retrospectivos , Pacientes Internos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Anciano de 80 o más Años
18.
J Arthroplasty ; 39(8S1): S95-S99, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38626864

RESUMEN

BACKGROUND: Despite the growing popularity of cementless total knee arthroplasty (TKA) in younger patients, the outcomes are unclear in the elderly population. We aimed to compare the clinical outcomes and survivorship of cementless TKA between different age groups. METHODS: Utilizing our prospectively collected institutional database, we retrospectively reviewed all patients undergoing primary cementless TKAs at a tertiary care institute. We identified 347 TKA, which were divided into 3 groups based on age at the time of surgery. Group A was ≤ 60 years, Group B was 60 to ≤ 70 years, and Group C was > 70 years. We compared clinical outcomes (Knee Society Clinical Rating System [KSCRS], Western Ontario and McMaster University Osteoarthritis Index [WOMAC], and Veterans Rand 12 Item Health Survey [VR-12]) and survivorship between the groups. RESULTS: At final follow-up, range of motion, KSCRS, WOMAC, and VR-12 physical score were comparable (P > .05). The VR-12 Mental score was higher in Group B and Group C than in Group A (P = .003). Compared to preoperative scores, the change in KSCRS, WOMAC, and VR-12 physical and mental scores was comparable at the final follow-up (P > .05). No patient underwent revision for aseptic loosening. CONCLUSIONS: There were no cases of revision surgery for aseptic loosening in our cohort of 347 cementless TKAs. Patients > 70 years of age undergoing cementless TKA can achieve clinical scores equivalent to those of younger patients at short term (2-year) follow-up. Longer-term survivorship is still required, but based on early data, cementless TKA can be a safe option for older patients.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Humanos , Artroplastia de Reemplazo de Rodilla/métodos , Artroplastia de Reemplazo de Rodilla/instrumentación , Anciano , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Factores de Edad , Falla de Prótesis , Osteoartritis de la Rodilla/cirugía , Rango del Movimiento Articular , Anciano de 80 o más Años , Articulación de la Rodilla/cirugía , Estudios de Seguimiento , Reoperación/estadística & datos numéricos
19.
J Arthroplasty ; 39(9S1): S208-S212, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38521249

RESUMEN

BACKGROUND: Modular titanium fluted tapered (TFT) stems have demonstrated excellent clinical success for femoral revision total hip arthroplasty (THA) surgery. This study reports the short-term outcomes of a novel modern monoblock TFT stem used for revision and complex primary THA with a minimum of 2 years of follow-up. METHODS: We identified 126 patients who received a single monoblock TFT stem: 26 patients for complex THA (failed fracture fixation) and 100 patients for revision THA. The reasons for revision THA included 40 for previous periprosthetic joint infection, 42 for aseptic loosening, 9 for trunnionosis, and 9 for periprosthetic fractures. The Paprosky grading for femoral bone loss at the time of surgery and the measured subsidence of femoral stems at 3-month follow-up were determined. We evaluated the number and indications for reoperations. RESULTS: The mean time from surgery was 3.9 years (range, 2.0 to 6.9). A paired t-test analysis showed significant improvement from preoperative versus postoperative clinical outcome scores (P < .001) for Harris Hip Score (38.76 ± 15.24 versus 83.42 ± 15.38), Western Ontario and McMaster Universities Arthritis Index (45.6 ± 19.0 versus 69.9 ± 21.3), Veterans RAND 12 Item Health Survey Physical component (31.7 ± 8.1 versus 37.8 ± 11.3), and Veterans RAND 12 Item Health Survey Mental component (48.2 ± 12.2 versus 51.6 ± 12.5). The Paprosky grading for femoral bone loss was Grade 1 (3.9%), Grade 2 (35.7%), Grade 3A (47.6%), Grade 3B (11.1%), and Grade 4 (1.6%) cases. There were 18 reoperations (14.7%), with 13 for periprosthetic joint infection (7 treated with implant retention and 6 treated with a 2-stage revision), 4 for instability, and 1 for acetabular aseptic loosening. There were no aseptic failures of the stem. CONCLUSIONS: This novel modern monoblock TFT stem provided reliable femoral fixation and has increasingly supplanted the use of modular TFT stems for complex primary and revision surgery in our institution.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Diseño de Prótesis , Reoperación , Titanio , Humanos , Artroplastia de Reemplazo de Cadera/instrumentación , Reoperación/estadística & datos numéricos , Masculino , Femenino , Prótesis de Cadera/efectos adversos , Persona de Mediana Edad , Anciano , Resultado del Tratamiento , Estudios de Seguimiento , Adulto , Anciano de 80 o más Años , Falla de Prótesis , Estudios Retrospectivos , Fémur/cirugía
20.
J Arthroplasty ; 39(9S1): S243-S247, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38848790

RESUMEN

BACKGROUND: Periprosthetic joint infection (PJI) continues to be one of the leading causes of failure following total hip arthroplasty (THA). The objectives of the study were to (1) determine the minimum 2-year infection-free survivorship of 2-stage revision THA, (2) determine the causative organisms for repeat 2-stage revision THA, and (3) characterize the results of failed 2-stage revisions and evaluate patient-reported outcome measures (PROMs). METHODS: A retrospective chart review was completed for patients who underwent 2-stage revision THA for PJI. Prospective data were collected on each patient, including demographics, causative organisms, complications, and type of reoperation. The PROMs, including Harris Hip Score, 12-item Short-Form Health Survey, and Western Ontario and McMaster Universities Osteoarthritis Index scores were obtained prior to 2-stage revision THA surgery and annually as part of standard clinical and radiographic follow-up. RESULTS: A total of 328 patients who underwent a 2-stage revision THA for a PJI were included in the study (mean age 67 years [range, 28 to 90], mean body mass index of 30.6 [range, 15 to 57]). The overall infection-free survivorship for 2-stage revision THA was 73.8% at a minimum of 2 years (range, 2 to 20). Overall, 194 (59.1%) patients who had successful infection eradication underwent a 2-revision THA only. The most common single organisms infected were Staphylococcus aureus (12.5%) and Staphylococcus epidermidis (11%). Higher reoperation rates were found in cases with methicillin-resistant Staphylococcus aureus and polymicrobial infections. All PROMs showed statistical improvement from preoperatively to the latest follow-up appointment. CONCLUSIONS: Two-stage revision THA is associated with a good success rate in the treatment of PJIs at mid-term to long-term follow-up. Polymicrobial and methicillin-resistant Staphylococcus aureus infections are poor prognostic factors, making the eradication of infection more difficult. The management of PJIs continues to be one of the most important orthopaedic challenges to treat.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Infecciones Relacionadas con Prótesis , Reoperación , Humanos , Artroplastia de Reemplazo de Cadera/efectos adversos , Reoperación/estadística & datos numéricos , Anciano , Persona de Mediana Edad , Masculino , Femenino , Infecciones Relacionadas con Prótesis/cirugía , Infecciones Relacionadas con Prótesis/etiología , Estudios Retrospectivos , Adulto , Estudios de Seguimiento , Anciano de 80 o más Años , Prótesis de Cadera/efectos adversos , Resultado del Tratamiento , Medición de Resultados Informados por el Paciente , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/etiología , Infecciones Estafilocócicas/cirugía
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