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1.
Europace ; 25(8)2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37622574

RESUMO

AIMS: Over the past 25 years there has been a substantial development in the field of digital electrophysiology (EP) and in parallel a substantial increase in publications on digital cardiology.In this celebratory paper, we provide an overview of the digital field by highlighting publications from the field focusing on the EP Europace journal. RESULTS: In this journey across the past quarter of a century we follow the development of digital tools commonly used in the clinic spanning from the initiation of digital clinics through the early days of telemonitoring, to wearables, mobile applications, and the use of fully virtual clinics. We then provide a chronicle of the field of artificial intelligence, a regulatory perspective, and at the end of our journey provide a future outlook for digital EP. CONCLUSION: Over the past 25 years Europace has published a substantial number of papers on digital EP, with a marked expansion in digital publications in recent years.


Assuntos
Cardiologia , Aplicativos Móveis , Humanos , Inteligência Artificial , Eletrofisiologia Cardíaca , Cognição
2.
Health Care Manag Sci ; 25(4): 526-550, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35652990

RESUMO

In hospitals, the efficient planning of the operating rooms (ORs) is difficult due to the uncertainty inherent to surgical services. This is especially true for the inpatient surgical department where complex and long surgeries are often performed along with surgeries on emergency patients. This paper aims to improve the scheduling of the inpatient department by partitioning the elective surgeries into the more predictable surgeries (MPS) group and the less predictable surgeries (LPS) group, based on surgery duration variability, and by scheduling each of the two surgery groups in different ORs. Through a simulation study that comprehensively investigates the impact of the partitioning on different performance measures under various environmental settings, we report important findings and insights. First, partitioning can effectively shorten the waiting times of elective patients for both MPS and LPS groups, but the option should be allowed to reassign patients from the MPS or LPS ORs to the other ORs when needed. Meanwhile, partitioning sometimes slightly increases the elective cancellation rate. Second, the ability to use the available capacity of the ORs as much as possible is key to reducing elective waiting times. Third, partitioning might slightly worsen the waiting times of emergency patients, while the slightly negative impact on emergency patients decreases when the number of ORs is higher. Fourth, the beneficial impact of partitioning on elective patients increases with an increased patient demand. Last, for the settings considered in this study there was no benefit in partitioning the elective patients into more than two groups.


Assuntos
Agendamento de Consultas , Eficiência Organizacional , Humanos , Pacientes Internados , Lipopolissacarídeos
3.
Med Care ; 58(1): 83-89, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31584461

RESUMO

BACKGROUND: Electronic Prescribing and Medicines Administration (EPMA) systems are being widely implemented to facilitate medication safety improvement. However, translating the resulting big data into actionable knowledge has received relatively little attention. OBJECTIVE: The objective of this study was to use routinely collected EPMA data in the study of exact time discrepancy between physicians' order and nurses' administration of systemic antibiotics. We evaluated first and follow-up dose administration and dose intervals and examined multifactorial determinants in ordering and administration explaining potential discrepancy. METHODS: We conducted an observational study of electronic health records for all medical patient stays with antibiotic treatment from January to June 2018 (n=4392) in a large Belgian tertiary care hospital. Using an EPMA system with Barcode Medication Administration, we calculated time discrepancy between order and administration of first doses (n=6233), follow-up doses (n=87 960), and dose intervals. Multiple logistic regression analysis estimated the association between time discrepancy and various determinants in ordering and administration. RESULTS: Time discrepancy between physician order and nurse administration was <30 minutes for 48.7% of first doses and 61.7% of follow-up doses, with large variation across primary diagnoses. Greater dose intervals, oral versus intravenous administration, and order diversion from regular nurse administration rounds showed strongest association with less timely administration. CONCLUSIONS: EPMA systems show huge potential to generate actionable knowledge. Concerning antibiotic treatment, having physicians' orders coincide with regular nurse administration rounds whenever clinically appropriate, further taking contextual factors into account, could potentially improve antibiotic administration timeliness.


Assuntos
Antibacterianos/uso terapêutico , Prescrições de Medicamentos/enfermagem , Prescrição Eletrônica/enfermagem , Padrões de Prática Médica/estatística & dados numéricos , Fatores de Tempo , Big Data , Humanos , Pesquisa Translacional Biomédica
5.
Clin Chem ; 64(9): 1370-1379, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29959147

RESUMO

BACKGROUND: Cardiac troponin T concentrations measured with high-sensitivity assays (hs-cTnT) provide important prognostic information for patients with stable coronary artery disease (CAD). However, whether hs-cTnT concentrations mainly reflect left ventricular (LV) remodeling or recurrent myocardial ischemia in this population is not known. METHODS: We measured hs-cTnT concentrations in 619 subjects with suspected stable CAD in a prospectively designed multicenter study. We identified associations with indices of LV remodeling, as assessed by cardiac MRI and echocardiography, and evidence of myocardial ischemia diagnosed by single positron emission computed tomography. RESULTS: Median hs-cTnT concentration was 7.8 ng/L (interquartile range, 4.8-11.6 ng/L), and 111 patients (18%) had hs-cTnT concentrations above the upper reference limit (>14 ng/L). Patients with hs-cTnT >14 ng/L had increased LV mass (144 ± 40 g vs 116 ± 34 g; P < 0.001) and volume (179 ± 80 mL vs 158 ± 44 mL; P = 0.006), lower LV ejection fraction (LVEF) (59 ± 14 vs 62 ± 11; P = 0.006) and global longitudinal strain (14.1 ± 3.4% vs 16.9 ± 3.2%; P < 0.001), and more reversible perfusion defects (P = 0.001) and reversible wall motion abnormalities (P = 0.008). Age (P = 0.009), estimated glomerular filtration rate (P = 0.01), LV mass (P = 0.003), LVEF (P = 0.03), and evidence of reversible myocardial ischemia (P = 0.004 for perfusion defects and P = 0.02 for LV wall motion) were all associated with increasing hs-cTnT concentrations in multivariate analysis. We found analogous results when using the revised US upper reference limit of 19 ng/L. CONCLUSIONS: hs-cTnT concentrations reflect both LV mass and reversible myocardial ischemia in patients with suspected stable CAD.


Assuntos
Angina Pectoris/fisiopatologia , Isquemia Miocárdica/prevenção & controle , Troponina T/sangue , Remodelação Ventricular , Idoso , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem
6.
Health Care Manag Sci ; 20(3): 326-352, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26860487

RESUMO

In many hospitals there are patients who receive surgery later than what is medically indicated. In one of Europe's largest hospitals, the University Hospital Leuven, this is the case for approximately every third patient. Serving patients late cannot always be avoided as a highly utilized OR department will sometimes suffer capacity shortage, occasionally leading to unavoidable delays in patient care. Nevertheless, serving patients late is a problem as it exposes them to an increased health risk and hence should be avoided whenever possible. In order to improve the current situation, the delay in patient scheduling had to be quantified and the responsible mechanism, the scheduling process, had to be better understood. Drawing from this understanding, we implemented and tested realistic patient scheduling methods in a discrete event simulation model. We found that it is important to model non-elective arrivals and to include elective rescheduling decisions made on surgery day itself. Rescheduling ensures that OR related performance measures, such as overtime, will only loosely depend on the chosen patient scheduling method. We also found that capacity considerations should guide actions performed before the surgery day such as patient scheduling and patient replanning. This is the case as those scheduling strategies that ensure that OR capacity is efficiently used will also result in a high number of patients served within their medically indicated time limit. An efficient use of OR capacity can be achieved, for instance, by serving patients first come, first served. As applying first come, first served might not always be possible in a real setting, we found it is important to allow for patient replanning.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38916231

RESUMO

OBJECTIVE: Uniform and standardised quality measurement allows care assessment and improvement. Following a pragmatic consensus method we aimed to agree on a selection of measurable quality indicators that can be used to assess, benchmark and gradually improve inflammatory bowel disease (IBD) care in Flanders. METHODS: Of 49 structures, 135 processes and 37 outcome indicators identified through literature, 58 were preselected and reformulated into measurable outcome indicators by four IBD physicians. A larger expert group scored the 58 indicators on a 10-point importance scale twice, endorsed by patient and expert perspectives in between rounds. Additional items could be suggested. A final selection and subset of indicators with room for improvement were agreed upon during a consensus meeting. RESULTS: Fifty indicators received an importance score of 7 or higher by ≥80% of the participants (seven IBD nurses, one abdominal surgeon, one chief medical officer and 31 IBD physicians including two paediatricians). Eight indicators scored highly important by 60-80%, two indicators reintroduced by patients and one newly suggested, were discussed during the consensus meeting. Among 26 participants, eight indicators were agreed to be added to the final selection. Of the 58 selected items, 19 were retained in the improvement subset, related to patient-reported outcomes, use of hospital services and survival, patient characteristics, monitoring of disease activity and remission, endoscopy guidelines, infection prevention, steroid and other medication use. CONCLUSION: Fifty-eight indicators were selected to assess IBD care in Flanders and a subset of 19 for use in clinical practice to steer quality improvement initiatives.

8.
J Cardiovasc Magn Reson ; 15: 46, 2013 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-23714095

RESUMO

UK Biobank is a prospective cohort study with 500,000 participants aged 40 to 69. Recently an enhanced imaging study received funding. Cardiovascular magnetic resonance (CMR) will be part of a multi-organ, multi-modality imaging visit in 3-4 dedicated UK Biobank imaging centres that will acquire and store imaging data from 100,000 participants (subject to successful piloting). In each of UK Biobank's dedicated bespoke imaging centres, it is proposed that 15-20 participants will undergo a 2 to 3 hour visit per day, seven days a week over a period of 5-6 years. The imaging modalities will include brain MRI at 3 Tesla, CMR and abdominal MRI at 1.5 Tesla, carotid ultrasound and DEXA scans using carefully selected protocols. We reviewed the rationale, challenges and proposed approaches for concise phenotyping using CMR on such a large scale. Here, we discuss the benefits of this imaging study and review existing and planned population based cardiovascular imaging in prospective cohort studies. We will evaluate the CMR protocol, feasibility, process optimisation and costs. Procedures for incidental findings, quality control and data processing and analysis are also presented. As is the case for all other data in the UK Biobank resource, this database of images and related information will be made available through UK Biobank's Access Procedures to researchers (irrespective of their country of origin and whether they are academic or commercial) for health-related research that is in the public interest.


Assuntos
Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Imageamento por Ressonância Magnética/métodos , Sistema de Registros , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Vigilância da População , Estudos Prospectivos , Reino Unido/epidemiologia
9.
Europace ; 15(7): 927-36, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23729412

RESUMO

Implantations of cardiac devices therapies and ablation procedures frequently depend on accurate and reliable imaging modalities for pre-procedural assessments, intra-procedural guidance, detection of complications, and the follow-up of patients. An understanding of echocardiography, cardiovascular magnetic resonance imaging, nuclear cardiology, X-ray computed tomography, positron emission tomography, and vascular ultrasound is indispensable for cardiologists, electrophysiologists as well as radiologists, and it is currently recommended that physicians should be trained in several imaging modalities. There are, however, no current guidelines or recommendations by electrophysiologists, cardiac imaging specialists, and radiologists, on the appropriate use of cardiovascular imaging for selected patient indications, which needs to be addressed. A Policy Conference on the use of imaging in electrophysiology and device management, with representatives from different expert areas of radiology and electrophysiology and commercial developers of imaging and device technologies, was therefore jointly organized by European Heart Rhythm Association (EHRA), the Council of Cardiovascular Imaging and the European Society of Cardiac Radiology (ESCR). The objectives were to assess the state of the level of evidence and a first step towards a consensus document for currently employed imaging techniques to guide future clinical use, to elucidate the issue of reimbursement structures and health economy, and finally to define the need for appropriate educational programmes to ensure clinical competence for electrophysiologists, imaging specialists, and radiologists.


Assuntos
Estimulação Cardíaca Artificial/normas , Cardiologia/normas , Ablação por Cateter/normas , Diagnóstico por Imagem/normas , Cardioversão Elétrica/normas , Técnicas Eletrofisiológicas Cardíacas/normas , Sociedades Médicas/normas , Estimulação Cardíaca Artificial/economia , Cardiologia/economia , Cardiologia/educação , Ablação por Cateter/economia , Consenso , Análise Custo-Benefício , Desfibriladores Implantáveis/normas , Diagnóstico por Imagem/economia , Diagnóstico por Imagem/métodos , Educação Médica , Cardioversão Elétrica/economia , Cardioversão Elétrica/instrumentação , Técnicas Eletrofisiológicas Cardíacas/economia , Europa (Continente) , Medicina Baseada em Evidências , Custos de Cuidados de Saúde , Humanos , Reembolso de Seguro de Saúde , Marca-Passo Artificial/normas
10.
Scand Cardiovasc J ; 47(6): 329-34, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24295289

RESUMO

OBJECTIVES: DOPPLER-CIP aims to determine the optimal noninvasive parameters (myocardial function, perfusion, ventricular blood flow, cell integrity) and methodology (ergometry, echocardiography, scintigraphy, MRI) in a given ischemic substrate that best predicts the impact of an intervention (or the lack thereof) on adverse morphological ventricular remodeling and functional recovery. Moreover, the relative predictive value of each of these parameters, in respect to the cost of extracting this information in order to enable optimization of cost-effectiveness for improved health care, will be determined by this project. DESIGN: DOPPLER-CIP is a multi-center registry study. All patients with ischemic heart disease included in this study undergo at least two noninvasive stress imaging examinations at baseline. The presence/or absence of left ventricular (LV) remodeling will be assessed after a follow-up of 2 years, during which all cardiac events will be registered. RESULTS: 676 patients were included. Currently, baseline data analysis is almost finished and the follow-up is ongoing. CONCLUSIONS: After completion, DOPPLER-CIP will provide evidence-based guidelines toward the most effective use of cardiac imaging in the chronically ischemic heart disease patient. The study will generate information, knowledge, and insight into the new imaging methodologies and into the pathophysiology of chronic ischemic heart disease.


Assuntos
Diagnóstico por Imagem , Isquemia Miocárdica/diagnóstico , Função Ventricular Esquerda , Remodelação Ventricular , Doença Crônica , Diagnóstico por Imagem/métodos , Ecocardiografia Doppler , Ecocardiografia sob Estresse , Ecocardiografia Tridimensional , Eletrocardiografia , Europa (Continente) , Teste de Esforço , Humanos , Imagem Cinética por Ressonância Magnética , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/terapia , Imagem de Perfusão , Valor Preditivo dos Testes , Prognóstico , Sistema de Registros , Inquéritos e Questionários , Tomografia Computadorizada de Emissão de Fóton Único
11.
J Clin Epidemiol ; 161: 127-139, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37536503

RESUMO

OBJECTIVES: To systematically review the risk of bias and applicability of published prediction models for risk of central line-associated bloodstream infection (CLA-BSI) in hospitalized patients. STUDY DESIGN AND SETTING: Systematic review of literature in PubMed, Embase, Web of Science Core Collection, and Scopus up to July 10, 2023. Two authors independently appraised risk models using CHecklist for critical Appraisal and data extraction for systematic Reviews of prediction Modelling Studies (CHARMS) and assessed their risk of bias and applicability using Prediction model Risk Of Bias ASsessment Tool (PROBAST). RESULTS: Sixteen studies were included, describing 37 models. When studies presented multiple algorithms, we focused on the model that was selected as the best by the study authors. Eventually we appraised 19 models, among which 15 were regression models and four machine learning models. All models were at a high risk of bias, primarily due to inappropriate proxy outcomes, predictors that are unavailable at prediction time in clinical practice, inadequate sample size, negligence of missing data, lack of model validation, and absence of calibration assessment. 18 out of 19 models had a high concern for applicability, one model had unclear concern for applicability due to incomplete reporting. CONCLUSION: We did not identify a prediction model of potential clinical use. There is a pressing need to develop an applicable model for CLA-BSI.


Assuntos
Sepse , Humanos , Viés , Prognóstico , Sepse/epidemiologia
12.
Expert Rev Med Devices ; 20(6): 467-491, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37157833

RESUMO

INTRODUCTION: Artificial intelligence (AI) encompasses a wide range of algorithms with risks when used to support decisions about diagnosis or treatment, so professional and regulatory bodies are recommending how they should be managed. AREAS COVERED: AI systems may qualify as standalone medical device software (MDSW) or be embedded within a medical device. Within the European Union (EU) AI software must undergo a conformity assessment procedure to be approved as a medical device. The draft EU Regulation on AI proposes rules that will apply across industry sectors, while for devices the Medical Device Regulation also applies. In the CORE-MD project (Coordinating Research and Evidence for Medical Devices), we have surveyed definitions and summarize initiatives made by professional consensus groups, regulators, and standardization bodies. EXPERT OPINION: The level of clinical evidence required should be determined according to each application and to legal and methodological factors that contribute to risk, including accountability, transparency, and interpretability. EU guidance for MDSW based on international recommendations does not yet describe the clinical evidence needed for medical AI software. Regulators, notified bodies, manufacturers, clinicians and patients would all benefit from common standards for the clinical evaluation of high-risk AI applications and transparency of their evidence and performance.


Assuntos
Inteligência Artificial , Software , Humanos , Algoritmos , União Europeia , Inquéritos e Questionários
13.
Lancet Digit Health ; 5(7): e467-e476, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37391266

RESUMO

The past decade has seen a dramatic rise in consumer technologies able to monitor a variety of cardiovascular parameters. Such devices initially recorded markers of exercise, but now include physiological and health-care focused measurements. The public are keen to adopt these devices in the belief that they are useful to identify and monitor cardiovascular disease. Clinicians are therefore often presented with health app data accompanied by a diverse range of concerns and queries. Herein, we assess whether these devices are accurate, their outputs validated, and whether they are suitable for professionals to make management decisions. We review underpinning methods and technologies and explore the evidence supporting the use of these devices as diagnostic and monitoring tools in hypertension, arrhythmia, heart failure, coronary artery disease, pulmonary hypertension, and valvular heart disease. Used correctly, they might improve health care and support research.


Assuntos
Doenças Cardiovasculares , Sistema Cardiovascular , Doença da Artéria Coronariana , Insuficiência Cardíaca , Dispositivos Eletrônicos Vestíveis , Humanos , Doenças Cardiovasculares/diagnóstico
14.
Med Care ; 50(9): 779-84, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22525610

RESUMO

BACKGROUND: Demand for surgical treatment is rising while operating room (OR) resources are limited. Requests for more resources therefore can only be partly met by repartitioning the existing sparse resources. OBJECTIVE: Our goal is to define a method to allocate OR block times among surgical disciplines in such a way that patients can be treated within an acceptable time after the need for surgery is established. In this paper, we introduce and explore the potential of the concept of the individual patient deviation from the optimal due time (DT) as a potential driver for OR (re-) allocation. STUDY DESIGN AND SETTING: Using retrospective data for abdominal and gynecologic surgery, we analyzed DT deviation and 3 additional modifiers. From this analysis, a reallocation of OR time to the different (sub-) specialties was calculated using a simple model. RESULTS: The results show the capability of measuring and visualizing relative overcapacity versus undercapacity of OR resources with respect to this patient-centered metric of DT. The reallocation results from the model show a potentially significant shift between programs. CONCLUSIONS: We propose the "due-time" concept as a valid measure to quantify OR resource use. The use of a DT-based model provides a transparent, acceptable system for regular reallocation of OR times between and within specialties.


Assuntos
Eficiência Organizacional , Alocação de Recursos para a Atenção à Saúde/métodos , Modelos Estatísticos , Salas Cirúrgicas/estatística & dados numéricos , Necessidades e Demandas de Serviços de Saúde , Humanos , Estudos Retrospectivos , Fatores de Tempo
15.
Biomed Eng Online ; 11: 51, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-22900831

RESUMO

BACKGROUND: In this paper a new non-invasive, operator-free, continuous ventricular stroke volume monitoring device (Hemodynamic Cardiac Profiler, HCP) is presented, that measures the average stroke volume (SV) for each period of 20 seconds, as well as ventricular volume-time curves for each cardiac cycle, using a new electric method (Ventricular Field Recognition) with six independent electrode pairs distributed over the frontal thoracic skin. In contrast to existing non-invasive electric methods, our method does not use the algorithms of impedance or bioreactance cardiography. Instead, our method is based on specific 2D spatial patterns on the thoracic skin, representing the distribution, over the thorax, of changes in the applied current field caused by cardiac volume changes during the cardiac cycle. Since total heart volume variation during the cardiac cycle is a poor indicator for ventricular stroke volume, our HCP separates atrial filling effects from ventricular filling effects, and retrieves the volume changes of only the ventricles. METHODS: ex-vivo experiments on a post-mortem human heart have been performed to measure the effects of increasing the blood volume inside the ventricles in isolation, leaving the atrial volume invariant (which can not be done in-vivo). These effects have been measured as a specific 2D pattern of voltage changes on the thoracic skin. Furthermore, a working prototype of the HCP has been developed that uses these ex-vivo results in an algorithm to decompose voltage changes, that were measured in-vivo by the HCP on the thoracic skin of a human volunteer, into an atrial component and a ventricular component, in almost real-time (with a delay of maximally 39 seconds). The HCP prototype has been tested in-vivo on 7 human volunteers, using G-suit inflation and deflation to provoke stroke volume changes, and LVot Doppler as a reference technique. RESULTS: The ex-vivo measurements showed that ventricular filling caused a pattern over the thorax quite distinct from that of atrial filling. The in-vivo tests of the HCP with LVot Doppler resulted in a Pearson's correlation of R = 0.892, and Bland-Altman plotting of SV yielded a mean bias of -1.6 ml and 2SD =14.8 ml. CONCLUSIONS: The results indicate that the HCP was able to track the changes in ventricular stroke volume reliably. Furthermore, the HCP produced ventricular volume-time curves that were consistent with the literature, and may be a diagnostic tool as well.


Assuntos
Equipamentos e Provisões Elétricas , Testes de Função Cardíaca/instrumentação , Monitorização Fisiológica/instrumentação , Volume Sistólico , Função Ventricular/fisiologia , Algoritmos , Calibragem , Feminino , Humanos , Masculino , Respiração , Fatores de Tempo
16.
World Hosp Health Serv ; 48(4): 14-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23484428

RESUMO

In this article, we explain why from our perspective as the largest academic medical center in the country, we consider it to be part of our mission to contribute to the elaboration of a value-based health care organization system. We describe our hospital quality management system and how we think that this can deliver added value by introducing lean principles in the care process. We also reflect on the importance of hospital accreditation and external benchmarking in the continuous quality improvement culture within the hospital.


Assuntos
Centros Médicos Acadêmicos/organização & administração , Gestão da Qualidade Total/organização & administração , Centros Médicos Acadêmicos/normas , Bélgica , Feminino , Humanos , Modelos Organizacionais , Estudos de Casos Organizacionais
17.
Pril (Makedon Akad Nauk Umet Odd Med Nauki) ; 43(2): 111-121, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35843916

RESUMO

Objective: Left ventricular hypertrophy in aortic stenosis, arterial hypertension or coarctation of the aorta is risk factor for early development of HF. In chronic late compared to early left ventricular afterload increases resulting from descending thoracic оr ascending aorta stenosis, we assess the left ventricular stroke work, pressure-volume area for О2 demand and effective work on the 4th and 8th weeks. It is suggested that reduced proximal thoracic aortic compliance presents with myocardial ischemia. However, development of adverse left ventricular hypertrophic remodeling and HF in different peak of LV afterload increase is understood poorly. Methods: Fourteen domestic male pigs (28 ± 3 kg) underwent descending thoracic or ascending aortic stenosis through posterior lateral thoracotomy, with cMRI and an invasive left ventricular pressure-volume loops' аrea assessment (Millar 5Fr pig-tailed conductance catheter) on the 4th and 8th weeks. Left ventricular stroke work and pressure-volume area PVA, parameter for LV O2 demand, were assessed in hypertrophic left ventricular remodeling, resulting from different peaks in LV afterload (late vs. early LV afterload) increase and we thus defined early adverse LV hypertrophic remodeling in linear and nonlinear end-systolic pressure-volume regression analysis. For this we used special software. Data was compared with two-way repeated measures ANOVA. Results presented are means ± (SEM) or medians and significance is set at p < 0.05. Results: The left ventricular nonlinear PVA was not different, in LL compared to EL on the 8th week and when using the linear regression analysis. Stroke work was not different. The linear and nonlinear potential energy were not different between LL vs. the EL group. Nonlinear bLVO2 demand was not different, being higher in LL compared to EL in the 8th week. Indexed PVA parameters were not different or changed between the 4th and 8th weeks, when being normalized for body surface-area (m²) or 100 grams of LV mass. Conclusion: The left ventricular potential energy, PVA with effective work and LVO2 demands are not different in hypertrophic LV remodeling in LL vs. EL group at the 8th week. Difference is not present when end-systolic pressure-volume relation is assessed from indexed LV volumes for m² BSA or 100 grams of LV mass. EL is as important as LL in increased LV afterloads based on LV work and mechanical coupling in this hypertensive heart failure model having preserved EF.


Assuntos
Estenose da Valva Aórtica , Acidente Vascular Cerebral , Aorta Torácica , Pressão Sanguínea , Constrição Patológica , Humanos , Masculino , Suínos , Função Ventricular Esquerda , Pressão Ventricular
18.
Artigo em Inglês | MEDLINE | ID: mdl-35843925

RESUMO

Background: In arterial hypertension, left ventricular relaxation is affected early on in relation to a chronic difference in peak left ventricular afterload with early development of HF. Objective: in ascending compares to descending thoracic aortic stenosis, resulting in chronic late and early LV afterload increase, to assess the left ventricular isovolumic relaxation pressure decay constant through regression analysis, a parameter of left ventricular relaxation on the 4th and 8th week period from invasive left ventricular pressure measurements. Methods: fourteen pigs underwent posterolateral thoracotomy for ascending aortic stenosis, resulting in chronic early left ventricular afterload increase (EL = 6], or descending thoracic aortic stenosis creating chronic late systolic left ventricular load (LL = 8]. Exponential regression with nonzero asymptote for τ assessment, with linear and nonlinear regression were performed on isovolumic relaxation pressure decay from the left ventricular invasive pressure measurements on 4th and 8th week. Two-way repeated measurement ANOVA, post-hoc Tukey test and linear regression were performed for statistical analysis. Results presented are mean ± SEM or median (quartiles], with significance is at p < 0.05. Results: The ascending aortic stenosis associated with prolonged biexponential asynchronous τ, compared to the descending thoracic aorta stenosis, resulted in data that were different at the 8th week in presence of respirations (interaction p < 0.05]. Monoexponential and linear τ were not different in either respiration being preserved or suspended transitionally and in preload reduction. Preload sensitive response of τ was found in ascending compared to descending thoracic aortic banding that reduced in EL and in LL it increased with load reduction (p < 0.05]. These results indicated that τ is not different in and between LV afterloading conditions in a chronic setting, although it indicates that myocardial ischemia is present and that it is greater in ascending aortic banding, compared to descending thoracic aorta banding at the 8th week. Conclusion: In different sequence of the left ventricular afterload, ventricular relaxation is affected early on, having in EL compared to LL prolonged biexponential asynchronous left ventricular relaxation constant, thus indicating the development left ventricular myocardial ischemia and different elastic recoil in an invasive left ventricular hemodynamic assessment.


Assuntos
Estenose da Valva Aórtica , Isquemia Miocárdica , Animais , Estenose da Valva Aórtica/cirurgia , Constrição Patológica , Ventrículos do Coração , Humanos , Contração Miocárdica , Suínos , Função Ventricular Esquerda/fisiologia
19.
Int J Cardiol ; 361: 14-17, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35577165

RESUMO

BACKGROUND: Elevated N-terminal pro-B-type natriuretic peptides (NT-proBNP) and cardiac troponin T (cTnT) are associated with poor outcome in patients with chronic coronary syndrome (CCS). The performance of these biomarkers in diagnosing ischemia, and their association with myocardial hypoperfusion and hypokinesis is unclear. METHODS: Patients with suspected CCS (history of angina, estimated cardiovascular risk >15% or a positive stress test) were included in the prospective, multi-center DOPPLER-CIP study. Patients underwent Single Positron Emission Computed Tomography for assessment of ischemia and NT-proBNP and cTnT were measured in venous blood samples. RESULTS: We included 430 patients (25% female) aged 64 ± 8 years. Reversible hypoperfusion and hypokinesis were present in 139 (32%) and 89 (21%), respectively. Concentrations of NT-proBNP and cTnT correlated moderately (rho = 0.50, p < 0.001). NT-proBNP and cTnT concentrations (median [IQR]) were higher in patients with versus without reversible ischemia: 150 (73-294) versus 87 (44-192) ng/L and 10 (6-13) versus 7 (4-11) ng/L, respectively (p < 0.001 for both), and the associations persisted after adjusting for possible confounders. The C-statistics to discriminate ischemia ranged from 63%-73%, were comparable for cTnT and NT-proBNP, and higher for hypokinesis than hypoperfusion, and both were superior to exercise electrocardiography and stress echocardiography. Very low concentrations (≤5 ng/L cTnT and ≤ 60 ng/L NT-proBNP) ruled out reversible hypokinesis with negative predictive value >90%. CONCLUSION: cTnT and NT-proBNP are associated with irreversible and reversible ischemia in patients with suspected CCS, particularly hypokinesis. The diagnostic performance was comparable between the biomarkers, and very low concentrations may reliably rule out ischemia.


Assuntos
Doença da Artéria Coronariana , Isquemia Miocárdica , Biomarcadores , Doença da Artéria Coronariana/diagnóstico , Feminino , Humanos , Masculino , Isquemia Miocárdica/diagnóstico por imagem , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Estudos Prospectivos , Troponina T
20.
JACC Cardiovasc Imaging ; 15(4): 607-625, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35033498

RESUMO

OBJECTIVES: The aim of this study was to compare the costs of a noninvasive cardiac magnetic resonance (CMR)-guided strategy versus 2 invasive strategies with and without fractional flow reserve (FFR). BACKGROUND: Coronary artery disease (CAD) is a major contributor to the public health burden. Stress perfusion CMR has excellent accuracy to detect CAD. International guidelines recommend as a first step noninvasive testing of patients in stable condition with known or suspected CAD. However, nonadherence in routine clinical practice is high. METHODS: In the EuroCMR (European Cardiovascular Magnetic Resonance) registry (n = 3,647, 59 centers, 18 countries) and the U.S.-based SPINS (Stress-CMR Perfusion Imaging in the United States) registry (n = 2,349, 13 centers, 11 states), costs were calculated for 12 health care systems (8 in Europe, the United States, 2 in Latin America, and 1 in Asia). Costs included diagnostic examinations (CMR and x-ray coronary angiography [CXA] with and without FFR), revascularizations, and complications during 1-year follow-up. Seven subgroup analyses covered low- to high-risk cohorts. Patients with ischemia-positive CMR underwent CXA and revascularization at the treating physician's discretion (CMR+CXA strategy). In the hypothetical invasive CXA+FFR strategy, costs were calculated for initial CXA and FFR in vessels with ≥50% stenoses, assuming the same proportion of revascularizations and complications as with the CMR+CXA strategy and FFR-positive rates as given in the published research. In the CXA-only strategy, costs included CXA and revascularizations of ≥50% stenoses. RESULTS: Consistent cost savings were observed for the CMR+CXA strategy compared with the CXA+FFR strategy in all 12 health care systems, ranging from 42% ± 20% and 52% ± 15% in low-risk EuroCMR and SPINS patients with atypical chest pain, respectively, to 31% ± 16% in high-risk SPINS patients with known CAD (P < 0.0001 vs 0 in all groups). Cost savings were even higher compared with CXA only, at 63% ± 11%, 73% ± 6%, and 52% ± 9%, respectively (P < 0.0001 vs 0 in all groups). CONCLUSIONS: In 12 health care systems, a CMR+CXA strategy yielded consistent moderate to high cost savings compared with a hypothetical CXA+FFR strategy over the entire spectrum of risk. Cost savings were consistently high compared with CXA only for all risk groups.


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Constrição Patológica , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Custos e Análise de Custo , Atenção à Saúde , Humanos , Valor Preditivo dos Testes , Sistema de Registros
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