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1.
PLoS Biol ; 16(2): e2004285, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29485983

RESUMO

The use of consumer-grade wearables for purposes beyond fitness tracking has not been comprehensively explored. We generated and analyzed multidimensional data from 233 normal volunteers, integrating wearable data, lifestyle questionnaires, cardiac imaging, sphingolipid profiling, and multiple clinical-grade cardiovascular and metabolic disease markers. We show that subjects can be stratified into distinct clusters based on daily activity patterns and that these clusters are marked by distinct demographic and behavioral patterns. While resting heart rates (RHRs) performed better than step counts in being associated with cardiovascular and metabolic disease markers, step counts identified relationships between physical activity and cardiac remodeling, suggesting that wearable data may play a role in reducing overdiagnosis of cardiac hypertrophy or dilatation in active individuals. Wearable-derived activity levels can be used to identify known and novel activity-modulated sphingolipids that are in turn associated with insulin sensitivity. Our findings demonstrate the potential for wearables in biomedical research and personalized health.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Monitores de Aptidão Física , Esfingolipídeos/sangue , Adulto , Cardiomegalia/diagnóstico , Exercício Físico , Feminino , Voluntários Saudáveis , Frequência Cardíaca , Humanos , Resistência à Insulina , Estilo de Vida , Masculino , Uso Excessivo dos Serviços de Saúde/prevenção & controle , Pessoa de Meia-Idade , Inquéritos e Questionários , Remodelação Ventricular
2.
Echocardiography ; 38(9): 1612-1617, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34505312

RESUMO

AIMS: Clinical guidelines recommend that the exercise protocol of a stress echocardiogram is selected to induce volitional exhaustion after a target duration of at least 8 minutes. While the Bruce protocol is very commonly used for clinical stress tests, it is known to be "steep", and many patients therefore fail to reach 8 minutes. We studied predictors of failure and developed a method for identifying patients not suitable for Bruce protocol which was accurate and yet simple enough to be used as a point-of-care decision support tool. METHODS AND RESULTS: We studied data out-patients undergoing Bruce protocol stress echocardiograms (n = 11 086) and analyzed predictors of inappropriate early termination (defined as test duration < 8 min as per current practice guidelines) using logistic regression. A prediction model was constructed as follows: .5 points were given for each of hypertension, diabetes, smoking, and E/e' > 7.9 in the resting echocardiogram; .1 point was added for each 1-unit increment in body mass index; 1 point was added for patient age by decade; 2.0 points were subtracted for male sex (p for all < 0.001). In tests on held-out validation data, the model was well calibrated (in plots of predicted vs actual risk) and discriminated failure versus non-failure well (C-statistic .86 for a score of 6.0 points; p < 0.001). CONCLUSION: These data may help to standardize protocol selection in stress echocardiography, by identifying patients pre-hoc where Bruce protocol will be inappropriately steep.


Assuntos
Ecocardiografia sob Estresse , Teste de Esforço , Índice de Massa Corporal , Exercício Físico , Humanos , Masculino
3.
Cardiovasc Ultrasound ; 18(1): 46, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33218338

RESUMO

BACKGROUND: Diastolic dysfunction can be caused by hypertension or diabetes mellitus, and it is also often found with increasing age. In a given patient, the cause of diastolic dysfunction is therefore not always obvious. We sought to study the interplay of these risk factors for diastolic dysfunction in an outpatient population with a low likelihood of ischemic heart disease. METHODS: Consecutive patients referred for stress echocardiography were included retrospectively. Exclusion criteria included pathological stress response, atrial arrhythmia, left ventricular ejection fraction < 55%, and more than mild valvular disease. Standard diastolic parameters were recorded in all patients. In a subset of patients, mechanistic analysis of early filling was performed using the parameterized diastolic filling (PDF) method. RESULTS: We included 726 patients (median [interquartile range] age 56 (44-65) years, 57% male). The prevalence of diabetes and hypertension was 43 and 49%, respectively. In multiple linear regression modeling, the presence of diabetes, hypertension, sex and increasing age explained a moderate amount of the variance in e' velocities, E/A ratio and E/e' (R2 = 0.31-0.48, p < 0.001), and a low amount of the variance in left atrial volume index (LAVI) and the PDF parameters (n = 446, R2 = 0.05-0.17, p < 0.001). Sex was only related to LAVI and E/e' for the conventional parameters (beta - 0.94, p = 0.04, and beta - 0.91, p < 0.001, respectively). CONCLUSIONS: Diabetes, hypertension, increasing age, and to a lesser extent sex, explain a moderate amount of the variance in conventional diastolic parameters related to myocardial tissue velocities and E/A ratio in a healthy outpatient population. The effect of these risk factors was substantially less pronounced on left atrial volume index and the PDF parameters.


Assuntos
Diabetes Mellitus/fisiopatologia , Ecocardiografia Doppler/métodos , Ecocardiografia sob Estresse/métodos , Hipertensão/fisiopatologia , Pacientes Ambulatoriais , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Idoso , Diástole , Feminino , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/fisiopatologia , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
4.
Am J Emerg Med ; 38(8): 1560-1567, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31493982

RESUMO

BACKGROUND: This study compared the performance of a single blood draw of high-sensitivity troponin T (hsTnT), high-sensitivity troponin I (hsTnI) and conventional troponin I (cTnI) within a modified HEART score for predicting 30-day MACE at Emergency Department (ED) presentation, and established local reference norms for all three assays by determining the cut-off point which yielded the highest sensitivity and negative predictive value for acute myocardial infarction and 30-day MACE. METHODS: This single-center prospective cohort study recruited chest pain patients at the ED, whose hsTnT, hsTnI and cTnI were taken on admission. Subjects were classified into low and non-low risk group according to their modified HEART score, with MACE as the primary endpoint. Receiver-operating characteristic (ROC) curves were generated, area under the curves (AUCs) were calculated; the performance characteristics were determined. RESULTS: The performance of modified HEART scores was comparable among the three assays for 30-day MACE (84.9-87.0% sensitivity, 95.6-96.0% NPV, 95%CI) and none of these had very high AUC and specificity (AUC 0.70-0.71, 53.7-56.7% specificity, 95% CI). The modified HEART score using a single blood draw of either hsTnT (3.9ng/L), hsTnI (0.9ng/L) or cTnI (0.0ng/L) at presentation yielded a sensitivity of 100% for 30-day MACE. CONCLUSION: The modified HEART score using a single blood draw of either hsTnT, hsTnI or cTnI was equally effective in risk-stratifying chest pain patients for safe discharge. The theoretical cut-off points yielding 100% sensitivity are potentially useful (when achieved) for safely discharging low risk patients with undifferentiated chest pain in the ED.


Assuntos
Serviço Hospitalar de Emergência , Infarto do Miocárdio/sangue , Troponina I/sangue , Troponina T/sangue , Adulto , Idoso , Biomarcadores/sangue , Dor no Peito/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Sensibilidade e Especificidade
5.
Echocardiography ; 37(4): 554-560, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32242982

RESUMO

BACKGROUND: Myocardial infarction (MI) is a high-risk condition especially when filling pressure is raised, and earlier reports have suggested that E/e' is associated with poor outcome. However, whether E/e' predicts risk better than LVEF, which is the current standard of practice, is not known. We investigated this question in the largest and most rigorous study of MI patients so far. METHODS AND RESULTS: We studied 660 patients with ST-elevation MI (STEMI) treated with primary percutaneous coronary intervention and related E/e' to short-term mortality (in-hospital death), as well as long-term events at 2 years comprising (a) a composite of MI, stroke, heart failure, and death, and (b) death alone. Short-term models were adjusted for age, sex, and LVEF. Long-term models were adjusted for age, sex, diabetes, revascularization procedure, history of MI, hypertension, renal function, drugs on discharge, and LVEF. Elevated E/e'> 15 indicated higher risk of short-term events (n = 19:7.0% (95% confidence interval 3.4-10.8%) vs. 1.0% (0.3 - 2.3%); adjusted odds ratio 3.7 (1.3-10.5)). While elevated E/e' was also associated with long-term outcomes (n = 103 composite events: 15.9% (11.9% - 21.4%) vs 6.8% (5.2% - 8.7%), P < .001; n = 38 death events: 6.0% (3.9% - 9.5%) vs 2.0% (1.3% - 3.2%), P = .001), E/e' was rendered nonsignificant for long-term outcomes by multivariable adjustment (p = ns for both). LVEF, on the contrary, was a highly significant predictor in the adjusted long-term model. CONCLUSION: E/e' is associated with poor outcome in STEMI, but LVEF is a stronger predictor of long-term risk.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Acidente Vascular Cerebral , Mortalidade Hospitalar , Humanos , Fatores de Risco , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Resultado do Tratamento
6.
BMC Cardiovasc Disord ; 19(1): 259, 2019 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752689

RESUMO

BACKGROUND: Cardiovascular disease (CVD) imposes much mortality and morbidity worldwide. The use of "deep learning", advancements in genomics, metabolomics, proteomics and devices like wearables have the potential to unearth new insights in the field of cardiology. Currently, in Asia, there are no studies that combine the use of conventional clinical information with these advanced technologies. We aim to harness these new technologies to understand the development of cardiovascular disease in Asia. METHODS: Singapore is a multi-ethnic country in Asia with well-represented diverse ethnicities including Chinese, Malays and Indians. The SingHEART study is the first technology driven multi-ethnic prospective population-based study of healthy Asians. Healthy male and female subjects aged 21-69 years old without any prior cardiovascular disease or diabetes mellitus will be recruited from the general population. All subjects are consented to undergo a detailed on-line questionnaire, basic blood investigations, resting and continuous electrocardiogram and blood pressure monitoring, activity and sleep tracking, calcium score, cardiac magnetic resonance imaging, whole genome sequencing and lipidomic analysis. Outcomes studied will include mortality and cause of mortality, myocardial infarction, stroke, malignancy, heart failure, and the development of co-morbidities. DISCUSSION: An initial target of 2500 patients has been set. From October 2015 to May 2017, an initial 683 subjects have been recruited and have completed the initial work-up the SingHEART project is the first contemporary population-based study in Asia that will include whole genome sequencing and deep phenotyping: including advanced imaging and wearable data, to better understand the development of cardiovascular disease across different ethnic groups in Asia.


Assuntos
Povo Asiático/genética , Doenças Cardiovasculares/genética , Adulto , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/prevenção & controle , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Nível de Saúde , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Singapura/epidemiologia , Sequenciamento Completo do Genoma , Adulto Jovem
7.
Environ Health ; 18(1): 34, 2019 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-30999903

RESUMO

BACKGROUND: Air pollution has a significant health impact. Most data originate from temperate regions. We aim to study the health impact of air pollution, particularly among the elderly, in a tropical region. METHODS: A daily time-series analysis was performed to estimate excess risk (ER) of various air pollutants on daily death counts amongst the general population in Singapore from 2001 to 2013. Air pollutants included particulate matters smaller than 10 µm, and 2.5 µm (PM10, PM2.5), carbon monoxide (CO), nitrogen dioxide (NO2), ozone (O3) and sulphur dioxide (SO2). The studied outcomes were non-accidental and cardiovascular mortality. Single-day lag and distributed lag models were studied and adjusted for confounders. RESULTS: In single-day lag models, a 10 µg/m3 increase in particulate matter was associated with significant increases in non-accidental (PM10 ER: 0.627%; 95% confidence interval (CI): 0.260-0.995% and PM2.5 ER: 0.660%; 95% CI: 0.204-1.118%) and cardiovascular mortality (PM10 ER: 0.897; 95% CI: 0.283-1.516 and PM2.5 ER: 0.883%; 95% CI: 0.121-1.621%). This was significant in the elderly ≥ 65 years but not in those < 65 years and were seen in the acute phase of lag 0-5 days. Effects by other pollutants were minimal. For cardiovascular mortality, the effects turned protective at a cumulative lag of 30 days in the elderly and could due to "harvesting". CONCLUSIONS: These first contemporary population-based data from an equatorial country with tropical climate show that exposure to particulate air pollution was significantly associated with non-accidental mortality and cardiovascular mortality, especially in the elderly.


Assuntos
Poluentes Atmosféricos/análise , Doenças Cardiovasculares/mortalidade , Material Particulado/análise , Adolescente , Adulto , Idoso , Poluição do Ar/análise , Monóxido de Carbono/análise , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Dióxido de Nitrogênio/análise , Ozônio/análise , Singapura/epidemiologia , Dióxido de Enxofre/análise , Adulto Jovem
8.
Circ J ; 82(7): 1836-1843, 2018 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-29695648

RESUMO

BACKGROUND: Cardiac size measurements require indexing to body size. Allometric indexing has been investigated in Caucasian populations but a range of different values for the so-called allometric power exponent (b) have been proposed, with uncertainty as to whether allometry offers clinical utility above body surface area (BSA)-based indexing. We derived optimal values for b in normal echocardiograms and validated them externally in cardiac patients. METHODS AND RESULTS: Values for b were derived in healthy adult Chinese males (n=1,541), with optimal b for left ventricular mass (LVM) of 1.66 (95% confidence interval 1.41-1.92). LV hypertrophy (LVH) defined as indexed LVM >75 g/m1.66 was associated with adverse outcomes in an external validation cohort (n=738) of patients with acute coronary syndrome (odds ratio for reinfarction: 2.4 (1.1-5.4)). In contrast, LVH defined by BSA-based indexing or allometry using exponent 2.7 exhibited no significant association with outcomes (P=NS for both). Cardiac longitudinal function also varied with body size: septal and RV free wall s', TAPSE and lateral e' all scaled allometrically (b=0.3-0.9). CONCLUSIONS: An optimal b of 1.66 for LVM in healthy Chinese was found to validate well, with superior clinical utility both to that of BSA-based indexing and to b=2.7. The effect of allometric indexing of cardiac function requires further study.


Assuntos
Ecocardiografia/normas , Coração/anatomia & histologia , Coração/fisiologia , Adulto , Povo Asiático , Tamanho Corporal , Humanos , Hipertrofia Ventricular Esquerda/diagnóstico , Masculino , Valores de Referência
9.
Eur Heart J ; 37(44): 3335-3342, 2016 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-27436867

RESUMO

AIMS: Ticagrelor reduces ischaemic events and mortality in acute coronary syndrome (ACS) vs. clopidogrel. We wished to study clinical outcomes in a large real-world population post-ACS. METHODS AND RESULTS: We performed a prospective cohort study in 45 073 ACS patients enrolled into Swedish Web system for Enhancement and Development of Evidence-based care in Heart Disease Evaluated According to Recommended Therapies who were discharged on ticagrelor (N = 11 954) or clopidogrel (N = 33 119) between 1 January 2010 and 31 December 2013. The primary outcome was a composite of all-cause death, re-admission with myocardial infarction (MI) or stroke, secondary outcomes as the individual components of the primary outcome, and re-admission with bleeding. The risk of the primary outcome with ticagrelor vs. clopidogrel was 11.7 vs. 22.3% (adjusted hazard ratio (HR) 0.85 [95% confidence interval: 0.78-0.93]), risk of death 5.8 vs. 12.9% (adjusted HR 0.83 [0.75-0.92]), and risk of MI 6.1 vs. 10.8% (adjusted HR 0.89 [0.78-1.01]) at 24 months. Re-admission with bleeding with ticagrelor vs. clopidogrel occurred in 5.5 vs. 5.2% (adjusted HR 1.20 [1.04-1.40]). In a subset of patients undergoing percutaneous coronary intervention (PCI) on ticagrelor vs. clopidogrel the PCI-related in-hospital bleeding was 3.7 vs. 2.7% (adjusted odds ratio, OR, 1.57 [1.30-1.90]). CONCLUSION: Ticagrelor vs. clopidogrel post-ACS was associated with a lower risk of death, MI, or stroke, as well as death alone. Risk of bleeding was higher with ticagrelor. These real-world outcomes are consistent with randomized trial results.


Assuntos
Infarto do Miocárdio , Síndrome Coronariana Aguda , Adenosina/análogos & derivados , Clopidogrel , Humanos , Inibidores da Agregação Plaquetária , Estudos Prospectivos , Sistema de Registros , Ticagrelor , Ticlopidina/análogos & derivados , Resultado do Tratamento
10.
Eur J Appl Physiol ; 116(7): 1355-65, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27179797

RESUMO

PURPOSE: The left ventricle (LV) ejects blood into the proximal aorta. Age and hypertension are associated with stiffening and dilation of the aortic root, typically viewed as indicative of adverse remodeling. Based on analytical considerations, we hypothesized that a larger aortic root should be associated with lower global afterload (effective arterial elastance, EA) and larger stroke volume (SV). Moreover, as antihypertensive drugs differ in their effect on central blood pressure, we examined the role of antihypertensive drugs for the relation between aortic root size and afterload. METHODS: We studied a large group of patients (n = 1250; 61 ± 12 years; 78 % males; 64 % hypertensives) from a single-center registry with known or suspected coronary artery disease. Aortic root size was measured by echocardiography as the diameter of the tubular portion of the ascending aorta. LV outflow tract Doppler was used to record SV. RESULTS: In the population as a whole, after adjusting for key covariates in separate regression models, aortic root size was an independent determinant of both SV and EA. This association was found to be heterogeneous and stronger in patients taking a calcium channel blocker (CCB; 10.6 % of entire population; aortic root size accounted for 8 % of the explained variance of EA). CONCLUSION: Larger aortic root size is an independent determinant of EA and SV. This association was heterogeneous and stronger in patients on CCB therapy.


Assuntos
Aorta/anatomia & histologia , Aorta/fisiologia , Pressão Arterial/fisiologia , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Pressão Ventricular/fisiologia , Aorta/diagnóstico por imagem , Simulação por Computador , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Tamanho do Órgão/fisiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Eur J Anaesthesiol ; 33(6): 450-6, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26950081

RESUMO

BACKGROUND: Perioperative myocardial damage and infarction (MI) is associated with increased mortality and other postoperative complications. OBJECTIVES: To assess the incidence of perioperative myocardial damage in patients undergoing major elective noncardiac surgery, to elucidate any association with postoperative MI and mortality and to estimate the impact of preoperative risk factors and intraoperative hypotension. DESIGN: Observational cohort study. SETTING: Karolinska University Hospital, Stockholm, Sweden, from October 2012 to May 2013. PATIENTS: In this single-centre study, all adult patients undergoing major elective noncardiac surgery who were scheduled for an overnight admission to the postoperative unit were included. Patients undergoing phaeochromocytoma surgery were excluded. Preoperative risk factors (co-morbidities), intraoperative events (hypotension defined as a 50% decrease in SBP relative to each patient's baseline and lasting >5 min) and postoperative data were collected from medical records. Levels of high-sensitivity cardiac troponin T (hs-cTnT) were measured on postoperative day 1. Myocardial damage was defined as an increase in the hs-cTnT value above 14 ng l. A cardiologist reviewed all cases of MI occurring within 30 days after surgery. MAIN OUTCOME MEASURES: Myocardial damage, MI and mortality within 30 days after surgery. RESULTS: Of the final cohort of 300 patients, 90 (30%) had myocardial damage on postoperative day 1 and 15 (5%) developed postoperative MI within 30 days. Multivariate logistic regression analysis demonstrated that an intraoperative reduction in SBP more than 50% from baseline lasting more than 5 min was an independent predictor of postoperative hs-cTnT elevation (odds ratio, 4.4; 95% confidence interval, 1.8 to 11.1). CONCLUSIONS: In a cohort of 300 patients undergoing major elective noncardiac surgery, there was a high incidence of myocardial damage and an association between an intraoperative reduction in SBP more than 50% from baseline lasting more than 5 min and myocardial damage.


Assuntos
Cardiomiopatias/epidemiologia , Cardiomiopatias/etiologia , Hipotensão/complicações , Hipotensão/epidemiologia , Complicações Intraoperatórias/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Estudos de Coortes , Eletrocardiografia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Complicações Pós-Operatórias/epidemiologia , Fatores de Risco , Procedimentos Cirúrgicos Operatórios , Troponina T/sangue
12.
J Physiol ; 593(8): 1901-12, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25630680

RESUMO

KEY POINTS: A hallmark of mitral stenosis (MS) is the markedly altered left ventricular (LV) loading. As most of the methods used to determine LV performance in MS patients are influenced by loading conditions, previous studies have shown conflicting results. The present study calculated LV elastance, which is a robust method to quantify LV function. We demonstrate that LV loading in MS patients is elevated but normalizes after valve repair and might be a result of reflex pathways. Additionally, we show that the LV in MS is less compliant than normal due to a combination of right ventricular loading and the valvular disease itself. Immediately after valve dilatation the increase in blood inflow into the LV results in even greater LV stiffness. Our findings enrich our understanding of heart function in MS patients and provide a simple reproducible way of assessing LV performance in MS. ABSTRACT: Left ventricular (LV) function in rheumatic mitral stenosis (MS) remains an issue of controversy, due to load dependency of previously employed assessment methods. We investigated LV performance in MS employing relatively load-independent indices robust to the altered loading state. We studied 106 subjects (32 ± 8 years, 72% female) with severe MS (0.8 ± 0.2 cm(2) ) and 40 age-matched controls. MS subjects underwent simultaneous bi-ventricular catheterization and transthoracic echocardiography (TTE) before and immediately after percutaneous transvenous mitral commisurotomy (PTMC). Sphygmomanometric brachial artery pressures and TTE recordings were simultaneously acquired in controls. Single-beat LV elastance (Ees ) was employed for LV contractility measurements. Effective arterial elastance (Ea ) and LV diastolic stiffness were measured. MS patients demonstrated significantly elevated afterload (Ea : 3.0 ± 1.3 vs. 1.5 ± 0.3 mmHg ml(-1) ; P < 0.001) and LV contractility (Ees : 4.1 ± 1.6 vs. 2.4 ± 0.5 mmHg ml(-1) ; P < 0.001) as compared to controls, with higher Ea in subjects with smaller mitral valve area (≤ 0.8 cm(2) ) and pronounced subvalvular fusion. Stroke volume (49 ± 16 to 57 ± 17 ml; P < 0.001) and indexed LV end-diastolic volume (LVEDVindex : 57 ± 16 to 64 ± 16 ml m(-2) ; P < 0.001) increased following PTMC while Ees and Ea returned to more normal levels. Elevated LV stiffness was demonstrated at baseline and increased further following PTMC. Our findings provide evidence of elevated LV contractility, increased arterial load and increased diastolic stiffness in severe MS. Following PTMC, both LV contractility and afterload tend to normalize.


Assuntos
Ventrículos do Coração/fisiopatologia , Hemodinâmica/fisiologia , Estenose da Valva Mitral/fisiopatologia , Função Ventricular Esquerda/fisiologia , Adulto , Ecocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Estenose da Valva Mitral/diagnóstico por imagem , Volume Sistólico/fisiologia , Adulto Jovem
13.
Am J Physiol Heart Circ Physiol ; 304(7): H1002-9, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23355342

RESUMO

Abnormal vascular-ventricular coupling has been suggested to contribute to heart failure with preserved ejection fraction in elderly females. Failure to increase stroke volume (SV) during exercise occurs in parallel with dynamic changes in arterial physiology leading to increased afterload. Such adverse vascular reactivity during stress may reflect either sympathoexcitation or be due to tachycardia. We hypothesized that afterload elevation induces SV failure by transiently attenuating left ventricular relaxation, a phenomenon described in animal research. The respective roles of tachycardia and sympathoexcitation were investigated in n = 28 elderly females (70 ± 4 yr) carrying permanent pacemakers. At rest, during atrial tachycardia pacing (ATP; 100 min(-1)) and during cold pressor test (hand immersed in ice water), we performed Doppler echocardiography (maximal untwist rate analyzed by speckle tracking imaging of rotational mechanics) and arterial tonometry (arterial stiffness estimated as augmentation index). Estimation of arterial compliance was based on an exponential relationship between arterial pressure and volume. We found that ATP produced central hypovolemia and a reduction in SV which was larger in patients with stiffer arteries (higher augmentation index). There was an associated adverse response of arterial compliance and vascular resistance during ATP and cold pressor test, causing an overall increase in afterload, but nonetheless enhanced maximal rate of untwist and no evidence of afterload-dependent failure of relaxation. In conclusion, tachycardia and cold provocation in elderly females produces greater vascular reactivity and SV failure in the presence of arterial stiffening, but SV failure does not arise secondary to afterload-dependent attenuation of relaxation.


Assuntos
Temperatura Baixa , Diástole , Sistema Nervoso Simpático/fisiopatologia , Taquicardia/fisiopatologia , Vasoconstrição , Fatores Etários , Idoso , Pressão Sanguínea , Artéria Braquial/fisiopatologia , Ecocardiografia sob Estresse , Feminino , Humanos , Hipertensão/fisiopatologia , Hipovolemia/fisiopatologia , Manometria , Marca-Passo Artificial , Artéria Radial/fisiopatologia , Volume Sistólico , Rigidez Vascular , Disfunção Ventricular/fisiopatologia
14.
Cardiovasc Ultrasound ; 11: 9, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23547949

RESUMO

BACKGROUND: Traditional echocardiographic methods like left ventricular ejection fraction(EF) and wall motion scoring (WMS) and new methods like speckle tracking (ST) based 2D strain carry important prognostic information in acute coronary syndrome (ACS) patients. Parameters from tissue Doppler imaging (TDI), with its high time resolution, may further increase the prognostic value. Peak systolic velocity (PSV) of the basal segments of the left ventricle from TDI is a robust and user independent parameter. The aim was to investigate the prognostic value of PSV compared to EF, WMS, 2D strain and E/e'. METHODS: Echocardiographic images were collected and post processed in 227 ACS patients. Additional clinical data was prospectively gathered and patients were followed for 3-5 years regarding the combined endpoint of death or re-admission due to ACS or heart failure. RESULTS: The combined endpoint occurred in 85 (37%) patients. Those with an event had lower median PSV than those without (4,4 cm/s) vs. (5,3 cm/s), (p<0.001). In a ROC analysis, the AUC was larger for PSV (0.75) than for EF (0.68), WMS (0.63), 2D strain (0.67) and E/e'(0.70). The combined endpoint increased with decreasing PSV. When adjusting for differences in baseline characteristics in a COX-regression model, PSV remained independently associated with outcome where the others did not. PSV was also less sensitive to image quality with fewer values missing or unacceptable for analysis. CONCLUSION: Peak systolic velocity (PSV) is a robust measurement that seems to have a strong and independent association with outcome compared to traditional echocardiographic measurements in ACS patients.


Assuntos
Síndrome Coronariana Aguda/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo/fisiologia , Ecocardiografia Doppler em Cores/métodos , Contração Miocárdica/fisiologia , Disfunção Ventricular Esquerda/etiologia , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Curva ROC , Sístole , Fatores de Tempo , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia
15.
Cardiovasc Ultrasound ; 11: 5, 2013 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-23360595

RESUMO

BACKGROUND: Aortic stenosis (AS) is a relevant common valve disorder. Severe AS and symptoms and/or left ventricular dysfunction (EF <50%) have the indication for aortic valve replacement (AVR). Majority of the patients with AS are elderly often with co-morbidities and generally have high preoperative risk. Transcatheter aortic valve implantation (TAVI) is offered in this group. Four different sizes of Corevalve prosthesis are available. Correct measurement of aortic size prior to TAVI is of great important to choose the right prosthesis size to avoid among others paravalvular leak or prosthesis patient mismatch.Aim of the study is to assess the aortic annulus diameter in patients undergoing TAVI by biplane (BP) mode using transesophageal echocardiography (TEE) and compare it to two-dimensional (2D) transthoracic echocardiography (TTE) and 2DTEE using three-dimensional (3D) TEE as reference method. METHODS: The study population consisted of 50 patients retrospectively (24 men and 26 women, mean age 85±8 years of age) who all had undergone echocardiography examination prior to TAVI. RESULTS: The mean aortic annulus diameter was 20.4±2.2 mm with TTE, 22.3±2.5 mm with 2DTEE, 22.9±1.9 mm with BP-mode and 23.1±1.9 mm with 3DTEE. TTE underestimated the mean aortic annulus diameter in comparison to transesophageal imaging modalities (p<0.001). Using 3DTEE, 2% of patients were unsuitable for TAVI due to a too-small AoA (n=1). This figure was similar with BP (4%, n=2; p=1.00) but considerably larger with 2DTTE (36%, n=18; p < 0.001) and 2DTEE (12%, n=6; p=0.06). There was a strong correlation between BP-mode and 3DTEE for assessment of aortic annulus diameter (r-value 0.88) with small mean difference (-0.2±0.9 mm) whereas the other modalities showed larger 95% confidence interval and modest correlation (2DTTE vs. 3DTEE, -6.3 to 0.9 mm, r=0.64 and 2DTEE vs. 3DTEE, -4.8 to 3.2 mm, r=0.61). CONCLUSION: A multi-dimensional method is preferred to assess aortic annulus diameter in TAVI patients since there is risk of underestimation using single plane. Biplane mode is the method of choice in view of speedy post-processing with no need for expensive dedicated software. Lastly, single plane methods lead to misclassification of patients as unsuitable for TAVI. This may be of major clinical importance.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Valva Aórtica/diagnóstico por imagem , Cateterismo Cardíaco , Ecocardiografia Transesofagiana/métodos , Implante de Prótese de Valva Cardíaca/métodos , Idoso de 80 Anos ou mais , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Ecocardiografia Tridimensional , Feminino , Seguimentos , Humanos , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença
16.
Heliyon ; 9(5): e15823, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37305473

RESUMO

Remodeling of the thoracic aorta is commonly seen and viewed as a precursor to an aortic aneurysm. However, while aneurysms have been shown to expand at a rate of approximately 1 mm annually, the expansion of the pre-aneurysmal aorta is poorly characterized, especially in relation to age, gender, and aortic size per se. We identified patients that had undergone echocardiography at least twice at a large university medical center. Diagnosis codes, medications, and blood test results were obtained from hospital records. Syndromic patients were excluded (e.g., Marfan's syndrome, bicuspid aortic valve). Final population comprised n = 24,928 patients (median age 61.2 years (inter-quartile range (IQR): 50.6-71.5); 55.8% males) that had undergone a median of 3 echocardiograms (2-4; range 2-27) during a median of 4.0 years (IQR: 2.3-6.2). Hypertension was present in 39.6% of patients and diabetes in 20.7%, median LV ejection fraction was 56.0% (IQR: 41.0-62.0). Aortic size measurements were analyzed in mixed models while clustering on individual patients. Mean expansion was determined for sinus of Valsalva as 1.93 (95% confidence interval; CI95: 1.87-1.99) mm per decade, and for ascending aorta as 1.76 (CI95: 1.70-1.82) mm per decade. Faster expansion was found in males, with larger aortic size, and younger age (p for interaction <0.05 for all). In conclusion, expansion of the thoracic aorta, in real world, non-syndromic patients, is slow and averages <2 mm per decade. This will help to inform management of this large patient group.

17.
J Clin Pharmacol ; 63(10): 1101-1107, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37139934

RESUMO

Patients with impaired left ventricular (LV) function can develop LV thrombus, a potentially life-threatening condition due to risk of stroke and embolization. Conventional treatment with vitamin K antagonists (VKAs; e.g., warfarin) puts patients at risk of bleeding, and the use of direct oral anticoagulants (DOACs) appears promising, although data are scant. We searched the published English language literature for randomized controlled trials (RCTs) comparing DOACs with VKAs in LV thrombus. End points were failure to resolve, thromboembolic events (stroke, embolism), bleeding, or any adverse event (composite of thromboembolism or bleeding), or all-cause death. Data were pooled and analyzed in hierarchical Bayesian models. In three eligible RCTs, 141 patients were studied during an average of 4.6 months (53.8 patient-years; n = 71 assigned to DOAC, n = 70 assigned to VKA). A similar number of patients in each treatment arm demonstrated failure to resolve (DOAC: 14/71 vs. VKA: 15/70) and death events (3/71 vs. 4/70). However, patients on DOACs suffered fewer strokes/thromboembolic events (1/71 vs. 7/70; log odds ratio [OR], -2.02 [95% credible interval (CI95 ), -4.53 to -0.31]) and fewer bleeding events (2/71 vs. 9/70; log OR, -1.62 [CI95 , -3.43 to -0.26]), leading to fewer patients on DOACs with any adverse event versus VKAs (3/71 vs. 16/70; log OR, -1.93 [CI95 , -3.33 to -0.75]). In conclusion, pooled analysis of RCT data favors DOACs over VKAs in patients with LV thrombus in terms of both efficacy and safety.


Assuntos
Acidente Vascular Cerebral , Trombose , Humanos , Varfarina/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Anticoagulantes/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Trombose/tratamento farmacológico , Trombose/induzido quimicamente , Administração Oral
18.
Eur J Appl Physiol ; 112(12): 4069-79, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22476861

RESUMO

Exercise can lead to release of biomarkers such as cardiac troponin T (cTnT) and N-terminal pro-brain natriuretic peptide (NT-proBNP), a poorly understood phenomenon proposed to especially occur with high-intensity exercise in less trained subjects. We hypothesised that haemodynamic perturbations during exercise are larger in athletes with cTnT release, and studied athletes with detectable cTnT levels after an endurance event (HIGH; n = 16; 46 ± 9 years) against matched controls whose levels were undetectable (LOW; n = 11; 44 ± 7 years). Echocardiography was performed at rest and at peak supine bicycle exercise stress. Left ventricular (LV) end-systolic elastance (E (LV) a load-independent measure of LV contractility), effective arterial elastance (E (A) a lumped index of arterial load) and end-systolic meridional wall stress were calculated from cardiac dimensions and brachial blood pressure. Efficiency of cardiac work was judged from the ventriculo-arterial coupling ratio (E (A)/E (LV): optimal range 0.5-1.0). While subgroups had similar values at rest, we found ventriculo-arterial mismatch during exercise in HIGH subjects [0.47 (0.39-0.58) vs. LOW: 0.73 (0.62-0.83); p < 0.01] due to unopposed increase in E (LV) (p < 0.05). In LOW subjects, a greater increase occurred in E (A) during exercise (+81 ± 67 % vs. HIGH: +39 ± 32 %; p = 0.02) which contributed to a maintained coupling ratio. Subjects with higher baseline NT-proBNP had greater systolic wall stress during exercise (R (2) = 0.39; p < 0.01) despite no correlation at rest (p = ns). In conclusion, athletes with exercise-induced biomarker release exhibit ventriculo-arterial mismatch during exercise, suggesting non-optimal cardiac work may contribute to this phenomenon.


Assuntos
Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Resistência Física/fisiologia , Corrida/fisiologia , Troponina/sangue , Função Ventricular Esquerda , Adulto , Atletas , Biomarcadores/sangue , Pressão Sanguínea , Débito Cardíaco , Estudos de Casos e Controles , Ecocardiografia , Teste de Esforço , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade
19.
Echocardiography ; 29(7): 766-72, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22494035

RESUMO

AIM: Whether measurement of left ventricular outflow tract diameter (LVOTd) using color Doppler (CD) in order to more accurately define LVOTd is more accurate for determination of stroke volume (SV) than gray scale and compare it with direct measurement of LVOT area (a) using three-dimensional echocardiography (3DE) for SV determination. METHODS AND RESULTS: Twenty-one volunteers were examined. LVOTa was calculated by two-dimensional echocardiography (2DE) using the following formula: π× (d/2)(2) , d = LVOT diameter by gray scale and CD, respectively. Planimetry of LVOTa was performed in parasternal long axis using 3DE. Eccentricity Index was calculated using the lateral and anterior-posterior LVOTd. SV was obtained by four different methods: (1) 2D gray scale, (2) 2D color, (3) LVOTa × LVOT velocity time integral, and (4) SV by Simpson's biplane method. Gray scale LVOTd was significantly smaller compared to LVOTd obtained with CD (P < 0.05). Significant differences occurred between LVOTa gray scale and CD (3.29 ± 0.74 cm(2) vs 3.67 ± 0.70 cm(2) , P < 0.05) and between LVOTa calculated by gray scale in comparison to 3DE planimetry; (3.29 ± 0.74 cm(2) vs 3.61 ± 0.89 cm(2) , P = 0.011). Half of the subjects had at least 17% difference between the lateral and anterior-posterior LVOTd. There were significant differences between SV by 2D gray scale and 2D CD (82.8 ± 17.1 mL vs 92.4 ± 16.8 mL, P < 0.05) and between 2D gray scale and 3DE planimetry (82.8 ± 17.1 mL vs 90.7 ± 19.8 mL, P = 0.025). CONCLUSION: Our study demonstrates LVOT being frequently elliptical. SV and LVOTa were found to be similar when comparing 2DE CD and 3DE planimetry and showed higher values in comparison to 2DE gray scale, which suggests 2DE CD to be an alternative approach for SV assessment.


Assuntos
Ecocardiografia Doppler em Cores/métodos , Ecocardiografia Tridimensional/métodos , Ventrículos do Coração/diagnóstico por imagem , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
20.
Health Econ Rev ; 12(1): 56, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348165

RESUMO

BACKGROUND: The clinical value and cost-effectiveness of invasive treatments for patients with coronary artery disease is unclear. Invasive treatments such as coronary artery bypass grafting and percutaneous coronary intervention are frequently used as a starting treatment, yet they are much more costly than optimal medical therapy. While patients may transition into other treatments over time, the choices of starting treatments are likely important determinants of costs and health outcomes. The aim is to predict by how much costs and health outcomes will change from a decision to use different starting treatments for patients with coronary artery disease in an Asian setting. METHODS: A cost-effectiveness study using a Markov model informed by data from Singapore General Hospital was done. All patients with initial presentations of stable coronary disease and no acute coronary syndromes who received medical treatments and interventional therapies were included. We compare existing practice, where the starting treatment can be medical therapy or stent percutaneous coronary interventions or coronary artery bypass grafting, with alternate starting treatment strategies. RESULTS: When compared to 'existing practice' a policy of starting 14% of patients with coronary artery bypass grafting and 86% with optimal medical therapy showed savings of $1,743 per patient and 0.23 additional quality adjusted life years. A change to policy nationwide would save $10 million and generate 1,380 quality adjusted life years. CONCLUSIONS: Increasing coronary artery bypass grafting and use of medical therapy in the setting of coronary artery disease is likely to saves costs and improve health outcomes. A definitive study to address the question we investigate would be very difficult to undertake and so using existing data to model the expected outcomes is a useful tool. There are likely to be large and complex barriers to the implementation of any policy change based on the findings of this study.

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