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《Mayo Clinic proceedings. Mayo Clinic》2021,96(10):2576-2586
ObjectiveTo validate an artificial intelligence–augmented electrocardiogram (AI-ECG) algorithm for the detection of preclinical left ventricular systolic dysfunction (LVSD) in a large community-based cohort.MethodsWe identified a randomly selected community-based cohort of 2041 subjects age 45 years or older in Olmsted County, Minnesota. All participants underwent a study echocardiogram and ECG. We first assessed the performance of the AI-ECG to identify LVSD (ejection fraction ≤40%). After excluding participants with clinical heart failure, we further assessed the AI-ECG to detect preclinical LVSD among all patients (n=1996) and in a high-risk subgroup (n=1348). Next we modelled an imputed screening program for preclinical LVSD detection where a positive AI-ECG triggered an echocardiogram. Finally, we assessed the ability of the AI-ECG to predict future LVSD. Participants were enrolled between January 1, 1997, and September 30, 2000; and LVSD surveillance was performed for 10 years after enrollment.ResultsFor detection of LVSD in the total population (prevalence, 2.0%), the area under the receiver operating curve for AI-ECG was 0.97 (sensitivity, 90%; specificity, 92%); in the high-risk subgroup (prevalence 2.7%), the area under the curve was 0.97 (sensitivity, 92%; specificity, 93%). In an imputed screening program, identification of one preclinical LSVD case would require 88.3 AI-ECGs and 8.7 echocardiograms in the total population and 65.7 AI-ECGs and 5.5 echocardiograms in the high-risk subgroup. The unadjusted hazard ratio for a positive AI-ECG for incident LVSD over 10 years was 2.31 (95% CI, 1.32 to 4.05; P=.004).ConclusionArtificial intelligence–augmented ECG can identify preclinical LVSD in the community and warrants further study as a screening tool for preclinical LVSD. 相似文献
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《Mayo Clinic proceedings. Mayo Clinic》2021,96(9):2323-2331
ObjectiveTo determine the impact of sleep-disordered breathing (SDB) on survival in patients with hypertrophic cardiomyopathy (HCM) following septal myectomy.Patients and MethodsPatients with obstructive HCM undergoing septal myectomy from 2007 to 2016 were reviewed. Those who had an overnight oximetry test within 6 months before myectomy were included in analysis. Oxygen desaturation index was examined continuously and also categorically (SDB [>5/h] and severe SDB [>15/h]).ResultsA total of 619 of 1500 patients undergoing septal myectomy had overnight oximetry tests. Sleep-disordered breathing (oxygen desaturation index >5/h) was identified in 338 (54.6%) patients, and among those patients, 117 (18.9%) were classified as severe. Patients with SDB were older, had greater body mass index and body surface area, were more likely to have arterial hypertension and atrial fibrillation, and had an increased E/e’ ratio on Doppler echocardiography. Notably, there was no difference in preoperative resting left ventricular outflow tract pressure gradient between patients with SDB and those with normal overnight oximetry (55 (interquartile range: 25 to 86) mm Hg versus 52 (interquartile range: 21 to 85) mm Hg; P=.29). There was no difference in age-adjusted survival among patients with normal oximetry compared with those with mild SDB (hazard ratio: 0.98; 95% CI: 0.45 to 2.17), and severe SDB (hazard ratio: 1.06, 95% CI 0.42 - 2.71).ConclusionSleep-disordered breathing is present in more than half of patients with obstructive HCM in whom septal myectomy is indicated, and is mainly associated with aging, overweight, and male sex. However, SDB does not alter survival following septal myectomy. 相似文献
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ObjectivesDespite its use in determining nigrostriatal degeneration, the lack of a consistent interpretation of nigrosome 1 susceptibility map-weighted imaging (SMwI) limits its generalized applicability. To implement and evaluate a diagnostic algorithm based on convolutional neural networks for interpreting nigrosome 1 SMwI for determining nigrostriatal degeneration in idiopathic Parkinson's disease (IPD).MethodsIn this retrospective study, we enrolled 267 IPD patients and 160 control subjects (125 patients with drug-induced parkinsonism and 35 healthy subjects) at our institute, and 24 IPD patients and 27 control subjects at three other institutes on approval of the local institutional review boards. Dopamine transporter imaging served as the reference standard for the presence or absence of abnormalities of nigrosome 1 on SMwI. Diagnostic performance was compared between visual assessment by an experienced neuroradiologist and the developed deep learning-based diagnostic algorithm in both internal and external datasets using a bootstrapping method with 10000 re-samples by the “pROC” package of R (version 1.16.2).ResultsThe area under the receiver operating characteristics curve (AUC) (95% confidence interval [CI]) per participant by the bootstrap method was not significantly different between visual assessment and the deep learning-based algorithm (internal validation, .9622 [0.8912–1.0000] versus 0.9534 [0.8779-0.9956], P = .1511; external validation, 0.9367 [0.8843-0.9802] versus 0.9208 [0.8634-0.9693], P = .6267), indicative of a comparable performance to visual assessment.ConclusionsOur deep learning-based algorithm for assessing abnormalities of nigrosome 1 on SMwI was found to have a comparable performance to that of an experienced neuroradiologist. 相似文献
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《Vaccine》2022,40(42):6153-6162
ObjectiveThis study was a randomized, double-blind, parallel-controlled trail to evaluate the rabies virus neutralizing activity(RVNA), safety and immunogenicity of Ormutivimab + rabies vaccine in Chinese healthy adults.MethodsSubjects were randomly and equally assigned to 4 groups (20 IU/kg Omtv + vaccine, 40 IU/kg Omtv + vaccine, 20 IU/kg HRIG + vaccine, and placebo + vaccine). Subjects received vaccine as the WHO Essen regime combined with Omutivimab、HRIG or placebo on Day 0. The study lasted for 43 days.ResultsA total of 240 subjects were simultaneously assigned to both FAS and SS. Fifty subjects with baseline RVNA > 0.05 IU/ml (detection limit) were excluded, 190 were included into mITT.All the subjects from 40 IU/kg Omtv + vaccine group had a protection level of RNVA (≥0.5 IU/ml, WHO) on Day 14, and those in 20 IU/kg Omtv + vaccine group and placebo + vaccine group converted positive 100 % on Day 28. In contrast to 20 IU/kg HRIG + vaccine and placebo + vaccine, Ormutivimab + vaccine provided a higher RVNA during Days 0 to 7. And RVNA in 40 IU/kg Omtv + vaccine and 20 IU/kg Omtv + vaccine groups were always higher than 20 IU/kg HRIG + vaccine group during the whole study. Although anti-Omtv antibody were detected in some subjects, it did not influence the RVNA. The incidence of adverse reactions was significantly lower in 20 IU/kg Omtv + vaccine group (17.2 %) than in 40 IU/kg Omtv + vaccine (36.7 %) and 20 IU/kg HRIG + vaccine groups (40.3 %).ConclusionCompared with HRIG + vaccine and placebo + vaccine, Omtv + vaccine provided higher RNVA for earlier immune protection. The interference of Ormutivimab on the long-term immune protection induced by rabies vaccine is weaker than HRIG. At the same dose, the adverse reactions of Omtv + vaccine group were less than HRIG + vaccine group.Registration: ClinicalTrials.gov #NCT02559921. 相似文献
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《Journal of vascular and interventional radiology : JVIR》2022,33(10):1213-1221.e5
PurposeTo investigate the pharmacokinetics (PK) and early effects of conventional transarterial chemoembolization (TACE) using sorafenib and doxorubicin on tumor necrosis, hypoxia markers, and angiogenesis in a rabbit VX2 liver tumor model.Materials and MethodsVX2 tumor-laden New Zealand White rabbits (N = 16) were divided into 2 groups: 1 group was treated with hepatic arterial administration of ethiodized oil and doxorubicin emulsion (DOX-TACE), and the other group was treated with ethiodized oil, sorafenib, and doxorubicin emulsion (SORA-DOX-TACE). Animals were killed within 3 days of the procedure. Levels of sorafenib and doxorubicin were measured in blood, tumor, and adjacent liver using mass spectrometry. Tumor necrosis was determined by histopathological examination. Intratumoral hypoxia-inducible factor (HIF) 1α, vascular endothelial growth factor (VEGF), and microvessel density (MVD) were determined by immunohistochemistry.ResultsThe median intratumoral concentration of sorafenib in the SORA-DOX-TACE group was 17.7 μg/mL (interquartile range [IQR], 7.42–33.5 μg/mL), and its maximal plasma concentration (Cmax) was 0.164 μg/mL (IQR, 0.0798–0.528 μg/mL). The intratumoral concentration and Cmax of doxorubicin were similar between the groups: 4.08 μg/mL (IQR, 3.18–4.79 μg/mL) and 0.677 μg/mL (IQR, 0.315–1.23 μg/mL), respectively, in the DOX-TACE group and 1.68 μg/mL (IQR, 0.795–4.08 μg/mL) and 0.298 μg/mL (IQR, 0.241–0.64 μg/mL), respectively, in the SORA-DOX-TACE group. HIF-1α expression was increased in the SORA-DOX-TACE group than in the DOX-TACE group. Tumor volume, tumor necrosis, VEGF expression, and MVD were similar between the 2 groups.ConclusionsThe addition of sorafenib to DOX-TACE delivered to VX2 liver tumors resulted in high intratumoral and low systemic concentrations of sorafenib without altering the PK of doxorubicin. 相似文献