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1.
Eur J Radiol ; 177: 111547, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38852329

RESUMO

BACKGROUND: Stroke, a leading global cause of mortality and neurological disability, is often associated with atherosclerotic carotid artery disease. Distinguishing between symptomatic and asymptomatic carotid artery disease is crucial for appropriate treatment decisions. Radiomics, a quantitative image analysis technique, and ML have emerged as promising tools in medical imaging, including neuroradiology. This systematic review and meta-analysis aimed to evaluate the methodological quality of studies employing radiomics for atherosclerotic carotid artery disease analysis and ML algorithms for culprit plaque identification using CT or MRI. MATERIALS AND METHODS: Pubmed, WoS and Scopus databases were searched for relevant studies published from January 2005 to May 2023. RQS assessed methodological quality of studies included in the review. QUADAS-2 assessed the risk of bias. A meta-analysis and three meta regressions were conducted on study performance based on model type, imaging modality and segmentation method. RESULTS: RQS assessed methodological quality, revealing an overall low score and consistent findings with other radiology domains. QUADAS-2 indicated an overall low risk, except for a single study with high bias. The meta-analysis demonstrated that radiomics-based ML models for predicting culprit plaques had a satisfactory performance, with an AUC of 0.85, surpassing clinical models. However, combining radiomics with clinical features yielded the highest AUC of 0.89. Meta-regression analyses confirmed these findings. MRI-based models slightly outperformed CT-based ones, but the difference was not significant. CONCLUSION: In conclusion, radiomics and ML hold promise for assessing carotid plaque vulnerability, aiding in early cerebrovascular event prediction. Combining radiomics with clinical data enhances predictive performance.


Assuntos
Doenças das Artérias Carótidas , Humanos , Doenças das Artérias Carótidas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Placa Aterosclerótica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Radiômica
3.
Cureus ; 16(4): e57494, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38707131

RESUMO

BACKGROUND: Post-prandial hyperglycemia (PPHG) remains a complex aspect in the management of type 2 diabetes mellitus (T2DM) in the Indian population due to uncertainty in the optimal utilization of alpha-glucosidase inhibitors (AGIs) either as standalone therapy or in combination, whether initiated initially or as a sequential therapy. METHODS: This was a post-approval, observational, multicentric clinical study conducted at 50 centers according to principles of the International Council for Harmonisation of Technical Requirements of Pharmaceuticals for Human Use Guideline for Good Clinical Practice (ICH-GCP) and Declaration of Helsinki and local ethics approval. Descriptive and analytical statistics were applied for conclusion and categorical variables using SPSS version 29.0.1.0 (171) (Armonk, NY: IBM Corp.). RESULTS: Protocol analyses of 515 cases revealed baseline demographics as follows: age 57.35±10.04 years, weight 72.86±10.92 kg, and BMI 28.33±6.07 kg/m2. Comorbidities included hypertension (N=169, 32.82%), thyroid disorders (N=99, 19.22%), and heart failure (N=92, 17.86%). Concomitant oral antidiabetics (OADs) prescribed as DPP4i (9.50%), SGLT2i (19.20%), and DPP4i+SGLT2i (7.20%). Study drug reduced glycosylated hemoglobin (HbA1c) by 13.77% (1.25% mean change, p<0.01), fasting blood glucose (FBG) by 23.69% (44.61 mg/dL mean change, p<0.01), post-prandial blood glucose (PPBG) by 24.57% (70.46 mg/dL mean change, p<0.01), and body weight by 4.43% (3.21 kg mean change, p<0.01) over 12 weeks. A total of 161 patients accomplished targeted PPBG of <180 mg/dL (119.13 mg/dL mean change, p<0.01). Regression analysis considering PPBG and HbA1c ≤7.5% showed a weak correlation between them (R-value=0.13, R-squared value=0.02), whereas between PPBG and HbA1c ≤9% yielded moderate positive correlation (R-value=0.53, R-squared value=0.28). There were no adverse events reported or analyzed during the observation period. CONCLUSION: Voglibose fixed-dose combination (FDC) demonstrates significant effectiveness at the initial dosage when started early in the management of T2DM and high PPBG levels. Moreover, it exhibits good tolerability, thereby contributing to higher compliance among Indian patients who consume a high-carbohydrate diet.

4.
medRxiv ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38798437

RESUMO

Importance: Extracranial internal carotid artery stenosis (50-99% arterial narrowing) is an important risk factor for ischemic stroke. Yet, the benefits and harms of targeted screening for asymptomatic carotid artery stenosis (ACAS) have not been assessed in population-based studies. Objective: To estimate the cost-effectiveness of one-time, targeted ACAS screening stratified by atherosclerotic cardiovascular disease (ASCVD) risk using the American Heart Association's Pooled Cohort Equations. Design Setting and Participants: We developed a lifetime microsimulation model of ACAS and stroke for a hypothetical cohort representative of US adults aged 50-80 years without stroke history. We used the Cardiovascular Health Study to estimate the probability and severity of ACAS based on individual characteristics (e.g., age, sex, smoking status, blood pressure, and cholesterol). Stroke risks were functions of these characteristics and ACAS severity. In the model, individuals testing positive for >70% stenosis with Duplex ultrasound and a confirmatory diagnostic test undergo revascularization, which may reduce the risk of stroke but also introduces complication risks. Diagnostic performance parameters, revascularization benefits and risks, utility weights, and costs were estimated from published sources. Cost-effectiveness was assessed from the health care sector perspective using a $100,000/quality-adjusted life year (QALY) threshold. Main Outcomes and Measures: Estimated stroke events prevented, lifetime costs, QALYs, and incremental cost-effectiveness ratios (ICERs) associated with ACAS screening. Costs (2023 USD) and QALYs were discounted at 3% annually. Results: We found that screening individuals with a 10-year ASCVD risk >30% was the most cost-effective strategy, with an ICER of $89,000/QALY. This strategy would make approximately 11.9% of the population eligible for screening, averting an estimated 24,084 strokes. Results were sensitive to variations in the efficacy and complication risk of revascularization. In probabilistic sensitivity analysis, screening those in lower ASCVD risk groups (0-20%) only had a 0.6% chance of being cost-effective. Conclusion and Relevance: A one-time screening may only be cost-effective for adults at a relatively high ASCVD risk. Our findings provide a framework that can be adapted as future clinical trial data continue to improve our understanding of the role of revascularization and intensive medical therapy in contemporary stroke prevention secondary to carotid disease.

5.
J Vasc Surg ; 79(3): 695-703, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939746

RESUMO

OBJECTIVE: The optimal management of patients with asymptomatic carotid stenosis (AsxCS) is enduringly controversial. We updated our 2021 Expert Review and Position Statement, focusing on recent advances in the diagnosis and management of patients with AsxCS. METHODS: A systematic review of the literature was performed up to August 1, 2023, using PubMed/PubMed Central, EMBASE and Scopus. The following keywords were used in various combinations: "asymptomatic carotid stenosis," "carotid endarterectomy" (CEA), "carotid artery stenting" (CAS), and "transcarotid artery revascularization" (TCAR). Areas covered included (i) improvements in best medical treatment (BMT) for patients with AsxCS and declining stroke risk, (ii) technological advances in surgical/endovascular skills/techniques and outcomes, (iii) risk factors, clinical/imaging characteristics and risk prediction models for the identification of high-risk AsxCS patient subgroups, and (iv) the association between cognitive dysfunction and AsxCS. RESULTS: BMT is essential for all patients with AsxCS, regardless of whether they will eventually be offered CEA, CAS, or TCAR. Specific patient subgroups at high risk for stroke despite BMT should be considered for a carotid revascularization procedure. These patients include those with severe (≥80%) AsxCS, transcranial Doppler-detected microemboli, plaque echolucency on Duplex ultrasound examination, silent infarcts on brain computed tomography or magnetic resonance angiography scans, decreased cerebrovascular reserve, increased size of juxtaluminal hypoechoic area, AsxCS progression, carotid plaque ulceration, and intraplaque hemorrhage. Treatment of patients with AsxCS should be individualized, taking into consideration individual patient preferences and needs, clinical and imaging characteristics, and cultural, ethnic, and social factors. Solid evidence supporting or refuting an association between AsxCS and cognitive dysfunction is lacking. CONCLUSIONS: The optimal management of patients with AsxCS should include BMT for all individuals and a prophylactic carotid revascularization procedure (CEA, CAS, or TCAR) for some asymptomatic patient subgroups, additionally taking into consideration individual patient needs and preference, clinical and imaging characteristics, social and cultural factors, and the available stroke risk prediction models. Future studies should investigate the association between AsxCS with cognitive function and the role of carotid revascularization procedures in the progression or reversal of cognitive dysfunction.


Assuntos
Estenose das Carótidas , Endarterectomia das Carótidas , Procedimentos Endovasculares , Acidente Vascular Cerebral , Humanos , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Medição de Risco , Resultado do Tratamento , Endarterectomia das Carótidas/efeitos adversos , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Procedimentos Endovasculares/efeitos adversos , Stents/efeitos adversos , Estudos Retrospectivos
6.
Ann Intern Med ; 176(5): 649-657, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37126821

RESUMO

BACKGROUND: The American Heart Association and American Stroke Association (AHA/ASA) endorsed 15 process measures for acute ischemic stroke (AIS) to improve the quality of care. Identifying the highest-value measures could reduce the administrative burden of quality measure adoption while retaining much of the value of quality improvement. OBJECTIVE: To prioritize AHA/ASA-endorsed quality measures for AIS on the basis of health impact and cost-effectiveness. DESIGN: Individual-based stroke simulation model. DATA SOURCES: Published literature. TARGET POPULATION: U.S. patients with incident AIS. TIME HORIZON: Lifetime. PERSPECTIVE: Health care sector. INTERVENTION: Current versus complete (100%) implementation at the population level of quality measures endorsed by the AHA/ASA with sufficient clinical evidence (10 of 15). OUTCOME MEASURES: Life-years, quality-adjusted life-years (QALYs), incremental cost-effectiveness ratios, and incremental net health benefits. RESULTS OF BASE-CASE ANALYSIS: Discounted life-years gained from complete implementation would range from 472 (tobacco use counseling) to 34 688 (early carotid imaging) for an annual AIS patient cohort. All AIS quality measures were cost-saving or highly cost-effective by AHA standards (<$50 000 per QALY for high-value care). Early carotid imaging and intravenous tissue plasminogen activator contributed the largest fraction of the total potential value of quality improvement (measured as incremental net health benefit), accounting for 72% of the total value. The top 5 quality measures accounted for 92% of the total potential value. RESULTS OF SENSITIVITY ANALYSIS: A web-based user interface allows for context-specific sensitivity and scenario analyses. LIMITATION: Correlations between quality measures were not incorporated. CONCLUSION: Substantial variation exists in the potential net benefit of quality improvement across AIS quality measures. Benefits were highly concentrated among 5 of 10 measures assessed. Our results can help providers and payers set priorities for quality improvement efforts and value-based payments in AIS care. PRIMARY FUNDING SOURCE: National Institute of Neurological Disorders and Stroke.

7.
J Family Med Prim Care ; 11(7): 3667-3672, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36387714

RESUMO

Introduction: Non-communicable diseases (NCDs) are increasing in trend and associated with modifiable risk factors and subsequently reducing physical activity; hence the Government of India (GOI) has launched a National Programme for Prevention and Control of Cancers, Diabetes, Cardiovascular Diseases and Stroke (NPCDCS) in 2010 to curb increasing prevalence. The present study was planned for assessment of the activities conducted under NPCDCS in rural Jaipur. Methods and Material: This observational study was conducted in rural Jaipur. NPCDCS reports, status of logistics and manpower were assessed for 1 year. Field level cross-checking survey was done to assess the gap between the actual screening work done and the work reported. All staffs were assessed for the level of awareness regarding NCDs as well as NPCDCS programs. Data were entered and analysed in Microsoft excel. Result: Around 48% (6674/13917) of persons >30 years were screened during 1 year study period. Around 51.5% of the screened persons had one or more NCDs (13.5% newly screened NCDs cases and 38% were prediagnosed of NCD cases). Status reports that 10 (83.33%) out of the total 12 expected reports were sent regularly on a monthly basis. Reason for not sending reports was a sudden lockdown due to COVID-19. Conclusion: The study concludes that the implementation of NPCDCS program activities is not in synch with the health staff awareness level. IEC activities were deficient and no work was done for adoption of behavioural change and healthy lifestyle. Actual cases of hypertension were more while cases of diabetes were less than the reported cases found on cross-check survey.

9.
J Family Med Prim Care ; 11(10): 6487-6492, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36618152

RESUMO

Background and Objectives: Women and newborns are most vulnerable during and immediately after childbirth. The majority of maternal and newborn deaths occurring in developing countries can be attributed to inabilities to access health services, illiteracy, social stigmas, and gender inequalities. Women should be made aware of the danger signs so that health care services can be assessed on time, thus reducing maternal mortality. The objectives of this study were to assess the knowledge about obstetric danger signs and to find out various factors associated with them among pregnant women attending antenatal care (ANC) clinic at the Rural Health Training Centre (RHTC) attached to a Medical College. Methodology: This cross-sectional study was conducted at the ANC clinic of the RHTC attached to a medical college of Rajasthan for a period of 4 months and included 353 pregnant women. A pre-designed and pre-tested schedule was used. Mean knowledge scores were computed and knowledge was classified into adequate and inadequate. Descriptive statistics were used and the Pearson Chi-square test was used as a test of significance, taking a P value of < 0.05 as statistically significant. Results: Educational status of pregnant women, antenatal check-up status and gravid status had significant associations with the knowledge of obstetric danger signs. Conclusions: About half of the respondents had adequate knowledge about the obstetrics danger signs. Therefore, there is a strong need of creating awareness in the community by improving access to health care.

10.
J Stroke ; 23(2): 202-212, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34102755

RESUMO

The optimal management of patients with asymptomatic carotid stenosis (ACS) is the subject of extensive debate. According to the 2017 European Society for Vascular Surgery guidelines, carotid endarterectomy should (Class IIa; Level of Evidence: B) or carotid artery stenting may be considered (Class IIb; Level of Evidence: B) in the presence of one or more clinical/imaging characteristics that may be associated with an increased risk of late ipsilateral stroke (e.g., silent embolic infarcts on brain computed tomography/magnetic resonance imaging, progression in the severity of ACS, a history of contralateral transient ischemic attack/stroke, microemboli detection on transcranial Doppler, etc.), provided documented perioperative stroke/death rates are <3% and the patient's life expectancy is >5 years. Besides these clinical/imaging characteristics, there are additional individual, ethnic/racial or social factors that should probably be evaluated in the decision process regarding the optimal management of these patients, such as individual patient needs/patient choice, patient compliance with best medical treatment, patient sex, culture, race/ethnicity, age and comorbidities, as well as improvements in imaging/operative techniques/outcomes. The present multispecialty position paper will present the rationale why the management of patients with ACS may need to be individualized.

11.
J Am Heart Assoc ; 9(20): e019307, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32941090

RESUMO

We, the Editors of the Journal of the American Heart Association, sincerely regret the publication of the article "Diversity, Inclusion, and Equity: Evolution of Race and Ethnicity Considerations for the Cardiology Workforce in the United States of America From 1969 to 2019".1 We are aware that the publication of this flawed and biased article has caused a great deal of unnecessary pain and anguish to a number of parties, and reflects extremely poorly on us. We fully support the retraction of this article.

13.
Circ Cardiovasc Qual Outcomes ; 13(7): e006492, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32615799

RESUMO

BACKGROUND: Healthcare payers in the United States are increasingly tying provider payments to quality and value using pay-for-performance policies. Cost-effectiveness analysis quantifies value in healthcare but is not currently used to design or prioritize pay-for-performance strategies or metrics. Acute ischemic stroke care provides a useful application to demonstrate how simulation modeling can be used to determine cost-effective levels of financial incentives used in pay-for-performance policies and associated challenges with this approach. METHODS AND RESULTS: Our framework requires a simulation model that can estimate quality-adjusted life years and costs resulting from improvements in a quality metric. A monetary level of incentives can then be back-calculated using the lifetime discounted quality-adjusted life year (which includes effectiveness of quality improvement) and cost (which includes incentive payments and cost offsets from quality improvements) outputs from the model. We applied this framework to an acute ischemic stroke microsimulation model to calculate the difference in population-level net monetary benefit (willingness-to-pay of $50 000 to $150 000/quality-adjusted life year) accrued under current Medicare policy (stroke payment not adjusted for performance) compared with various hypothetical pay-for-performance policies. Performance measurement was based on time-to-thrombolytic treatment with tPA (tissue-type plasminogen activator). Compared with current payment, equivalent population-level net monetary benefit was achieved in pay-for-performance policies with 10-minute door-to-needle time reductions (5057 more acute ischemic stroke cases/y in the 0-3-hour window) incentivized by increasing tPA payment by as much as 18% to 44% depending on willingness-to-pay for health. CONCLUSIONS: Cost-effectiveness modeling can be used to determine the upper bound of financial incentives used in pay-for-performance policies, although currently, this approach is limited due to data requirements and modeling assumptions. For tPA payments in acute ischemic stroke, our model-based results suggest financial incentives leading to a 10-minute decrease in door-to-needle time should be implemented but not exceed 18% to 44% of current tPA payment. In general, the optimal level of financial incentives will depend on willingness-to-pay for health and other modeling assumptions around parameter uncertainty and the relationship between quality improvements and long-run quality-adjusted life expectancy and costs.


Assuntos
Custos de Cuidados de Saúde , AVC Isquêmico/economia , AVC Isquêmico/terapia , Planos de Incentivos Médicos/economia , Melhoria de Qualidade/economia , Indicadores de Qualidade em Assistência à Saúde/economia , Reembolso de Incentivo/economia , Adulto , Idoso , Idoso de 80 Anos ou mais , Simulação por Computador , Análise Custo-Benefício , Feminino , Humanos , AVC Isquêmico/diagnóstico , Expectativa de Vida , Masculino , Pessoa de Meia-Idade , Modelos Econômicos , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
14.
Cardiovasc Diagn Ther ; 9(5): 420-430, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31737514

RESUMO

BACKGROUND: Most cardiovascular (CV)/stroke risk calculators using the integration of carotid ultrasound image-based phenotypes (CUSIP) with conventional risk factors (CRF) have shown improved risk stratification compared with either method. However such approaches have not yet leveraged the potential of machine learning (ML). Most intelligent ML strategies use follow-ups for the endpoints but are costly and time-intensive. We introduce an integrated ML system using stenosis as an endpoint for training and determine whether such a system can lead to superior performance compared with the conventional ML system. METHODS: The ML-based algorithm consists of an offline and online system. The offline system extracts 47 features which comprised of 13 CRF and 34 CUSIP. Principal component analysis (PCA) was used to select the most significant features. These offline features were then trained using the event-equivalent gold standard (consisting of percentage stenosis) using a random forest (RF) classifier framework to generate training coefficients. The online system then transforms the PCA-based test features using offline trained coefficients to predict the risk labels on test subjects. The above ML system determines the area under the curve (AUC) using a 10-fold cross-validation paradigm. The above system so-called "AtheroRisk-Integrated" was compared against "AtheroRisk-Conventional", where only 13 CRF were considered in a feature set. RESULTS: Left and right common carotid arteries of 202 Japanese patients (Toho University, Japan) were retrospectively examined to obtain 395 ultrasound scans. AtheroRisk-Integrated system [AUC =0.80, P<0.0001, 95% confidence interval (CI): 0.77 to 0.84] showed an improvement of ~18% against AtheroRisk-Conventional ML (AUC =0.68, P<0.0001, 95% CI: 0.64 to 0.72). CONCLUSIONS: ML-based integrated model with the event-equivalent gold standard as percentage stenosis is powerful and offers low cost and high performance CV/stroke risk assessment.

15.
BMC Pregnancy Childbirth ; 19(1): 378, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31651276

RESUMO

BACKGROUND: Several risk factors predisposing women and their live-borns to adverse outcomes during pregnancy have been documented. Little is known about sanitation being a factor contributing to adverse pregnancy outcomes in India. The role of sanitation in adverse pregnancy outcomes remains largely unexplored in the Indian context. This study is an attempt to bring the focus on sanitation as a factor in adverse pregnancy outcome. Along with the sanitation factors, few confounder variables have also been studied in order to understand the adverse pregnancy outcomes. METHODS: The study is based on the fourth round of National Family Health Survey (NFHS-IV) covering 26,972 married women in the age-group 15-49. The study variables include the mother's age, Body Mass Index (BMI), education, anemia, and Antenatal care (ANC) visits during their last pregnancy. The household level variable includes place of residence, religion, caste, wealth index, access to toilet, type of toilet, availability of water within toilet premises, and facility of hand wash near the toilet. Children study variables include Low Birth Weight (LBW), the order of birth (Parity), and the death of the children of the women in the last 5 years. The target variable Adverse Pregnancy Outcome (APO) was constructed using children born with low birth weight or died during the last pregnancy. RESULTS: We calculated both adjusted as well as unadjusted odds ratios for a better understanding of the association between sanitation and adverse pregnancy outcomes. Findings from the study showed that women who did not have access to a toilet within the house had a higher risk of adverse pregnancy outcome. In the multivariable model, no association was observed for adverse pregnancy outcome among women who did not have access to toilet and women who used shared toilet. Teenage (15-19 years), uneducated, underweight and anemic mothers were more likely to face APO as compare to other mothers in similar characteristics group. CONCLUSIONS: Our findings contribute to the decidedly less available literature on maternal sanitation behaviour and adverse pregnancy outcomes. Our results support that sanitation is a very significant aspect for women who are about to deliver a baby as there was an association between sanitation and adverse pregnancy outcome. Education on sanitation practices is the need of the hour as much as it needs to follow.


Assuntos
Mães/estatística & dados numéricos , Resultado da Gravidez/epidemiologia , Saneamento/estatística & dados numéricos , Banheiros/estatística & dados numéricos , Adolescente , Adulto , Demografia , Características da Família , Feminino , Inquéritos Epidemiológicos , Humanos , Índia/epidemiologia , Lactente , Mortalidade Infantil , Recém-Nascido de Baixo Peso , Recém-Nascido , Pessoa de Meia-Idade , Razão de Chances , Paridade , Gravidez , Fatores de Risco , Classe Social , Adulto Jovem
16.
J Am Heart Assoc ; 8(21): e012739, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31645165

RESUMO

Background Imaging may play an important role in identifying high-risk plaques in patients who have carotid disease and who could benefit from surgical revascularization. We sought to evaluate the cost effectiveness of a decision-making rule based on the ultrasound imaging assessment of plaque echolucency in patients with asymptomatic carotid stenosis. Methods and Results We used a decision-analytic model to project lifetime quality-adjusted life years and costs for 5 stroke prevention strategies: (1) medical therapy only; (2) revascularization if both plaque echolucency and stenosis progression to >90% are present; (3) revascularization only if plaque echolucency is present; (4) revascularization only if stenosis progression >90% is present; or (5) either plaque echolucency or stenosis progression is present. Risks of clinical events, costs, and quality-of-life values were estimated based on published sources and the analysis was conducted from a healthcare system perspective for asymptomatic patients with 70% to 89% carotid stenosis at presentation. Patients who did not undergo revascularization had the highest stroke events (17.6%) and lowest life-years (8.45), while those who underwent revascularization on the basis of either presence of plaque echolucency on ultrasound or progression of carotid stenosis had the lowest stroke events (12.0%) and longest life-years (14.41). The either plaque echolucency or progression-based revascularization group had an incremental cost-effectiveness ratio of $110 000/quality-adjusted life years compared with the plaque echolucency-based strategy, which had an incremental cost-effectiveness ratio of $29 000/quality-adjusted life years compared with the joint echolucency and progression-based strategy. Conclusions Plaque echolucency on ultrasound can be a cost-effective tool to identify patients with asymptomatic carotid artery stenosis most likely to benefit from carotid endarterectomy.


Assuntos
Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/epidemiologia , Análise Custo-Benefício , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/epidemiologia , Ultrassonografia Doppler/economia , Idoso , Idoso de 80 Anos ou mais , Doenças Assintomáticas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco
17.
Curr Atheroscler Rep ; 21(7): 25, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31041615

RESUMO

PURPOSE OF REVIEW: Cardiovascular disease (CVD) and stroke risk assessment have been largely based on the success of traditional statistically derived risk calculators such as Pooled Cohort Risk Score or Framingham Risk Score. However, over the last decade, automated computational paradigms such as machine learning (ML) and deep learning (DL) techniques have penetrated into a variety of medical domains including CVD/stroke risk assessment. This review is mainly focused on the changing trends in CVD/stroke risk assessment and its stratification from statistical-based models to ML-based paradigms using non-invasive carotid ultrasonography. RECENT FINDINGS: In this review, ML-based strategies are categorized into two types: non-image (or conventional ML-based) and image-based (or integrated ML-based). The success of conventional (non-image-based) ML-based algorithms lies in the different data-driven patterns or features which are used to train the ML systems. Typically these features are the patients' demographics, serum biomarkers, and multiple clinical parameters. The integrated (image-based) ML-based algorithms integrate the features derived from the ultrasound scans of the arterial walls (such as morphological measurements) with conventional risk factors in ML frameworks. Even though the review covers ML-based system designs for carotid and coronary ultrasonography, the main focus of the review is on CVD/stroke risk scores based on carotid ultrasound. There are two key conclusions from this review: (i) fusion of image-based features with conventional cardiovascular risk factors can lead to more accurate CVD/stroke risk stratification; (ii) the ability to handle multiple sources of information in big data framework using artificial intelligence-based paradigms (such as ML and DL) is likely to be the future in preventive CVD/stroke risk assessment.


Assuntos
Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/prevenção & controle , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/prevenção & controle , Ultrassonografia/métodos , Algoritmos , Doenças das Artérias Carótidas/complicações , Aprendizado Profundo , Humanos , Infarto do Miocárdio/etiologia , Placa Aterosclerótica/complicações , Medição de Risco/métodos , Medição de Risco/tendências , Fatores de Risco , Acidente Vascular Cerebral/etiologia
18.
Comput Biol Med ; 91: 306-317, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29107894

RESUMO

BACKGROUND: This pilot study presents a completely automated, novel, smart, cloud-based, point-of-care system for (a) carotid lumen diameter (LD); (b) stenosis severity index (SSI) and (c) total lumen area (TLA) measurement using B-mode ultrasound. The proposed system was (i) validated against manual reading taken by the Neurologist and (ii) benchmarked against the commercially available system. METHOD: One hundred patients (73 M/27 F, mean age: 68 ± 11 years), institutional review board approved, written informed consent, consisted of left/right common carotid artery (200 ultrasound scans) were acquired using a 7.5-MHz linear transducer. RESULTS: The measured mean LD for left and right carotids were (in mm): (i) for proposed system (6.49 ± 1.77, 6.66 ± 1.70); and (ii) for manual (6.29 ± 1.79, 6.45 ± 1.63), respectively and coefficient of correlation between cloud-based automated against manual were 0.98 (P < 0.0001) and 0.99 (P < 0.0001), respectively. The corresponding TLA error, Precision-of-Merit, and Figure-of-Merit when measured against the manual were: 4.56 ± 3.54%, 96.18 ± 3.21%, and 96.85%, respectively. The AUC for the receiving operating characteristics for the cloud-based system was: 1.0. Four statistical tests such as: Two-tailed z-test, Mann-Whitney test, Kolmogorov-Smirnov (KS) and one-way ANOVA were performed to demonstrate consistency and reliability. CONCLUSIONS: The proposed system is reliable, accurate, fast, completely automated, anytime-anywhere solution for multi-center clinical trials and routine vascular screening.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Internet , Acidente Vascular Cerebral/epidemiologia , Ultrassonografia/métodos , Idoso , Espessura Intima-Media Carotídea , Estenose das Carótidas/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Acidente Vascular Cerebral/diagnóstico por imagem
19.
Comput Methods Programs Biomed ; 141: 73-81, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28241970

RESUMO

BACKGROUND AND OBJECTIVES: Standardization of the carotid IMT requires a reference marker in ultrasound scans. It has been shown previously that manual reference marker and manually created carotid segments are used for measuring IMT in these segments. Manual methods are tedious, time consuming, subjective, and prone to errors. Bulb edge can be considered as a reference marker for measurements of the cIMT. However, bulb edge can be difficult to locate in ultrasound scans due to: (a) low signal to noise ratio in the bulb region as compared to common carotid artery region; (b) uncertainty of bulb location in craniocaudal direction; and (c) variability in carotid bulb shape and size. This paper presents an automated system (a class of AtheroEdge™ system from AtheroPoint™, Roseville, CA, USA) for locating the bulb edge as a reference marker and further develop segmental-IMT (sIMT) which measures IMT in 10mm segments (namely: s1, s2 and s3) proximal to the bulb edge. METHODS: The patented methodology uses an integrated approach which combines carotid geometry and pixel-classification paradigms. The system first finds the bulb edge and then measures the sIMT proximal to the bulb edge. The system also estimates IMT in bulb region (bIMT). The 649 image database consists of varying plaque (light, moderate to heavy), image resolutions, shapes, sizes and ethnicity. RESULTS: Our results show that the IMT contributions in different carotid segments are as follows: bulb-IMT 34%, s1-IMT 29.46%, s2-IMT 11.48%, and s3-IMT 12.75%, respectively. We compare our automated results against reader's tracings demonstrating the following performance: mean lumen-intima error: 0.01235 ± 0.01224mm, mean media-adventitia error: 0.020933 ± 0.01539mm and mean IMT error: 0.01063 ± 0.0031mm. Our system's Precision of Merit is: 98.23%, coefficient of correlation between automated and Reader's IMT is: 0.998 (p-value < 0.0001). These numbers are improved compared to previous publications by Suri's group which is automated multi-resolution conventional cIMT. CONCLUSIONS: Our fully automated bulb detection system reports 92.67% precision against ideal bulb edge locations as marked by the reader in the bulb transition zone.


Assuntos
Automação , Espessura Intima-Media Carotídea , Acidente Vascular Cerebral/epidemiologia , Sistemas de Gerenciamento de Base de Dados , Humanos , Reprodutibilidade dos Testes , Medição de Risco
20.
PLoS One ; 11(2): e0148106, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26840397

RESUMO

BACKGROUND: Thrombolytic treatment (tissue-type plasminogen activator [tPA]) is only recommended for acute ischemic stroke patients with stroke onset time <4.5 hours. tPA is not recommended when stroke onset time is unknown. Diffusion-weighted MRI (DWI) and fluid attenuated inversion recovery (FLAIR) MRI mismatch information has been found to approximate stroke onset time with some accuracy. Therefore, we developed a micro-simulation model to project health outcomes and costs of MRI-based treatment decisions versus no treatment for acute wake-up stroke patients. METHODS AND FINDINGS: The model assigned simulated patients a true stroke onset time from a specified probability distribution. DWI-FLAIR mismatch estimated stroke onset <4.5 hours with sensitivity and specificity of 0.62 and 0.78, respectively. Modified Rankin Scale (mRS) scores reflected tPA treatment effectiveness accounting for patients' true stroke onset time. Discounted lifetime costs and benefits (quality-adjusted life years [QALYs]) were projected for each strategy. Incremental cost-effectiveness ratios (ICERs) were calculated for the MRI-based strategy in base-case and sensitivity analyses. With no treatment, 45.1% of simulated patients experienced a good stroke outcome (mRS score 0-1). Under the MRI-based strategy, in which 17.0% of all patients received tPA despite stroke onset times >4.5 hours, 46.3% experienced a good stroke outcome. Lifetime discounted QALYs and costs were 5.312 and $88,247 for the no treatment strategy and 5.342 and $90,869 for the MRI-based strategy, resulting in an ICER of $88,000/QALY. Results were sensitive to variations in patient- and provider-specific factors such as sleep duration, hospital travel and door-to-needle times, as well as onset probability distribution, MRI specificity, and mRS utility values. CONCLUSIONS: Our model-based findings suggest that an MRI-based treatment strategy for this population could be cost-effective and quantifies the impact that patient- and provider-specific factors, such as sleep duration, hospital travel and door-to-needle times, could have on the optimal decision for wake-up stroke patients.


Assuntos
Modelos Econômicos , Modelos Neurológicos , Neuroimagem/economia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/economia , Acidente Vascular Cerebral/terapia , Neuroimagem/métodos
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