Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 86
Filtrar
1.
Ann Thorac Surg ; 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33667463

RESUMO

BACKGROUND: Pulmonary endarterectomy (PEA) is a curative procedure for patients with chronic thromboembolic pulmonary hypertension. Body composition and exercise capacity have been associated with adverse outcomes in patients undergoing cardiothoracic surgeries, but their significance with PEA is unclear. We evaluated the association of body composition and 6-minute walk distance (6MWD) with disease severity, hospital length of stay, discharge disposition and post-operative functional recovery. METHODS: Retrospective, single-center cohort study of patients who underwent PEA (Jan/2014-Dec/2017). Body composition (skeletal muscle mass and adiposity cross sectional area, body mass index) was quantified using thoracic computed tomography with Slice-O-Matic software. Association of body composition measures and 6MWD with clinical outcomes was evaluated using multivariable regression models. RESULTS: 127 patients (58±14 years; 42% males, Body Mass Index: 31±7 kg/m2, 6MWD: 361±165 m) were included. Muscle and 6MWD were associated with disease severity measures. Of those surviving hospitalization (n=125), a greater 6MWD was associated with a shorter hospital stay (1.9 median days per 100m, p<0.001) and higher likelihood of being discharged directly home from hospital (OR: 2.1 per 100m, p= 0.004), independent of age, sex and body mass index. Those with a lower pre-operative 6MWD (per 100m) had a greater increase in their post-operative 6MWD (52m, p< 0.0001), independent of age, sex, and body mass index. Body composition measures were not associated with hospital outcomes or exercise capacity in the first-year post-operatively. CONCLUSIONS: Exercise capacity was a more prognositc marker of PEA outcomes compared to body composition. Future research is needed to explore pre-PEA rehabilitation strategies.

2.
Sci Rep ; 11(1): 483, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436837

RESUMO

Quantitative measurement of lung perfusion is a promising tool to evaluate lung pathophysiology as well as to assess disease severity and monitor treatment. However, this novel technique has not been adopted clinically due to various technical and physiological challenges; and it is still in the early developmental phase where the correlation between lung pathophysiology and perfusion maps is being explored. The purpose of this research work is to quantify the impact of pulmonary artery occlusion on lung perfusion indices using lung dynamic perfusion CT (DPCT). We performed Lung DPCT in ten anesthetized, mechanically ventilated juvenile pigs (18.6-20.2 kg) with a range of reversible pulmonary artery occlusions (0%, 40-59%, 60-79%, 80-99%, and 100%) created with a balloon catheter. For each arterial occlusion, DPCT data was analyzed using first-pass kinetics to derive blood flow (BF), blood volume (BV) and mean transit time (MTT) perfusion maps. Two radiologists qualitatively assessed perfusion maps for the presence or absence of perfusion defects. Perfusion maps were also analyzed quantitatively using a linear segmented mixed model to determine the thresholds of arterial occlusion associated with perfusion derangement. Inter-observer agreement was assessed using Kappa statistics. Correlation between arterial occlusion and perfusion indices was evaluated using the Spearman-rank correlation coefficient. Our results determined that perfusion defects were detected qualitatively in BF, BV and MTT perfusion maps for occlusions larger than 55%, 80% and 55% respectively. Inter-observer agreement was very good with Kappa scores > 0.92. Quantitative analysis of the perfusion maps determined the arterial occlusion threshold for perfusion defects was 50%, 76% and 44% for BF, BV and MTT respectively. Spearman-rank correlation coefficients between arterial occlusion and normalized perfusion values were strong (- 0.92, - 0.72, and 0.78 for BF, BV and MTT, respectively) and were statically significant (p < 0.01). These findings demonstrate that lung DPCT enables quantification and stratification of pulmonary artery occlusion into three categories: mild, moderate and severe. Severe (occlusion ≥ 80%) alters all perfusion indices; mild (occlusion < 55%) has no detectable effect. Moderate (occlusion 55-80%) impacts BF and MTT but BV is preserved.

3.
J Am Heart Assoc ; 9(22): e016339, 2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33153377

RESUMO

Background Resting right heart catheterization can assess both left heart filling and pulmonary artery (PA) pressures to identify and classify pulmonary hypertension. Although exercise may further elucidate hemodynamic abnormalities, current pulmonary hypertension classifications do not consider the expected interrelationship between PA and left heart filling pressures. This study explored the utility of this relationship to enhance the classification of exercise hemodynamic phenotypes in pulmonary hypertension. Methods and Results Data from 36 healthy individuals (55, 50-60 years, 50% male) and 85 consecutive patients (60, 49-71 years, 48% male) with dyspnea and/or suspected pulmonary hypertension of uncertain etiology were analyzed. Right heart catheterization was performed at rest and during semiupright submaximal cycling. To classify exercise phenotypes in patients, upper 95% CIs were identified from the healthy individuals for the change from rest to exercise in mean PA pressure over cardiac output (ΔmPAP/ΔCO ≤3.2 Wood units [WU]), pulmonary artery wedge pressure over CO (ΔPAWP/ΔCO ≤2 mm Hg/L per minute), and exercise PA pulse pressure over PAWP (PP/PAWP ≤2.5). Among patients with a ΔmPAP/ΔCO ≤3.2 WU, the majority (84%) demonstrated a ΔPAWP/ΔCO ≤2 mm Hg/L per minute, yet 23% demonstrated an exercise PP/PAWP >2.5. Among patients with a ΔmPAP/ΔCO >3.2 WU, 37% had an exercise PP/PAWP >2.5 split between ΔPAWP/ΔCO groups. Patients with normal hemodynamic classification declined from 52% at rest to 36% with exercise. Conclusions The addition of PP/PAWP to classify exercise hemodynamics uncovers previously unrecognized abnormal phenotypes within each ΔmPAP/ΔCO group. Our study refines abnormal exercise hemodynamic phenotypes based on an understanding of the interrelationship between PA and left heart filling pressures.

4.
Heart ; 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32748799

RESUMO

OBJECTIVES: Although a life-preserving surgery for children with single ventricle physiology, the Fontan palliation is associated with striking morbidity and mortality with advancing age. Our primary objective was to evaluate the impact of non-invasive, external, thoraco-abdominal ventilation on pulmonary blood flow (PBF) and cardiac output (CO) as measured by cardiovascular magnetic resonance (CMR) imaging in adult Fontan subjects. METHODS: Adults with a dominant left ventricle post-Fontan palliation (lateral tunnel or extracardiac connections) and healthy controls matched by sex and age were studied. We evaluated vascular flows using phase-contrast CMR imaging during unassisted breathing, negative pressure ventilation (NPV) and biphasic ventilation (BPV). Measurements were made within target vessels (aorta, pulmonary arteries, vena cavae and Fontan circuit) at baseline and during each ventilation mode. RESULTS: Ten Fontan subjects (50% male, 24.5 years (IQR 20.8-34.0)) and 10 matched controls were studied. Changes in PBF and CO, respectively, were greater following BPV as compared with NPV. In subjects during NPV, PBF increased by 8% (Δ0.20 L/min/m2 (0.10-0.53), p=0.011) while CO did not change significantly (Δ0.17 L/min/m2 (-0.11-0.23), p=0.432); during BPV, PBF increased by 25% (Δ0.61 L/min/m2 (0.20-0.84), p=0.002) and CO increased by 16% (Δ0.47 L/min/m2 (0.21-0.71), p=0.010). Following BPV, change in PBF and CO were both significantly higher in subjects versus controls (0.61 L/min/m2 (0.2-0.84) vs -0.27 L/min/m2 (-0.55-0.13), p=0.001; and 0.47 L/min/m2 (0.21-0.71) vs 0.07 L/min/m2 (-0.47-0.33), p=0.034, respectively). CONCLUSION: External ventilation acutely augments PBF and CO in adult Fontan subjects. Confirmation of these findings in larger populations with longer duration of ventilation and extended follow-up will be required to determine sustainability of haemodynamic effects.

5.
EClinicalMedicine ; 23: 100396, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32529180

RESUMO

Background: Preoperative spirometry and cardiopulmonary exercise testing (CPET) may stratify risk for respiratory complications. This secondary analysis of the Measurement of Exercise Tolerance before Surgery (METS) study examined whether CPET performance (i.e., cardiopulmonary fitness) confounds associations of spirometry with outcomes. Methods: The analysis included 1200 participants having major non-cardiac surgery at 25 hospitals in Canada, Australia, New Zealand and UK. Forced expiratory volume in 1 s (FEV1), and ratio of FEV1 to forced vital capacity (FVC) were measured during preoperative spirometry, and peak oxygen consumption and ventilatory efficiency during preoperative CPET. Outcomes were respiratory morbidity (Postoperative Morbidity Survey) and pulmonary complications (pneumonia or respiratory failure). We used multivariable logistic regression models to estimate associations of FEV1 with outcomes after adjustment for risk factors and either peak oxygen consumption or ventilatory efficiency. Findings: 128 participants (11%) developed respiratory morbidity, and 48 (4%) developed pulmonary complications. There was no strong evidence that FEV1 predicted respiratory morbidity after adjustment for peak oxygen consumption (p = 0·80) or ventilatory efficiency (p = 0·76), or FEV1 predicted pulmonary complications after adjustment for ventilatory efficiency (p = 0·37). Peak oxygen consumption (odds ratio 0·66 per 5 mL/kg/min increase; 95% CI, 0·54-0·82) was associated with respiratory morbidity. Ventilatory efficiency was associated with respiratory morbidity (p = 0·04) and pulmonary complications (p = 0·02). Peak oxygen consumption also confounded the association between FEV1 and respiratory morbidity. Interpretation: After accounting for fitness and clinical factors, FEV1 was not strongly predictive of respiratory complications. Prior associations between FEV1 and respiratory morbidity may be explained by confounding by peak oxygen consumption. Funding: Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Ontario Ministry of Health and Long-Term Care, Ontario Ministry of Research, Innovation and Science, UK National Institute of Academic Anaesthesia, UK Clinical Research Collaboration, Australian and New Zealand College of Anaesthetists, and Monash University.

7.
Heliyon ; 5(7): e02034, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31317084

RESUMO

Objectives: Our aims were to evaluate HRV in pulmonary hypertension (WHO Group 1 and 4) compared to control subjects, and to assess whether the presence of sleep apnea in those with pulmonary hypertension would be deleterious and cause greater impairment in HRV. Methods: This retrospective case-control study analyzed electrocardiogram segments obtained from diagnostic polysomnography. Results: Forty-one pulmonary hypertension patients were compared to 41 age, sex and apnea-hypopnea index matched healthy controls. The pulmonary hypertension group had decreased high frequency, very low frequency, low frequency, and percentage of normal R-R intervals that differ by > 50 ms compared to control subjects. Moderate to severe right ventricle dysfunction on echocardiography was a predictor of lower high frequency in pulmonary hypertension patients. Conclusions: There were no differences in any HRV measures in pulmonary hypertension patients with or without sleep apnea. Impaired HRV was demonstrated in pulmonary hypertension patients however, the presence of sleep apnea did not appear to further reduce vagal modulation.

8.
Heliyon ; 5(7): 1-8, Jul 2019.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1006879

RESUMO

Objectives: Our aims were to evaluate HRV in pulmonary hypertension (WHO Group 1 and 4) compared to control subjects, and to assess whether the presence of sleep apnea in those with pulmonary hypertension would be deleterious and cause greater impairment in HRV. Methods: This retrospective case-control study analyzed electrocardiogram segments obtained from diagnostic polysomnography. Results: Forty-one pulmonary hypertension patients were compared to 41 age, sex and apnea-hypopnea index matched healthy controls. The pulmonary hypertension group had decreased high frequency, very low frequency, low frequency, and percentage of normal R-R intervals that differ by > 50 ms compared to control subjects. Moderate to severe right ventricle dysfunction on echocardiography was a predictor of lower high frequency in pulmonary hypertension patients. Conclusions: There were no differences in any HRV measures in pulmonary hypertension patients with or without sleep apnea. Impaired HRV was demonstrated in pulmonary hypertension patients however, the presence of sleep apnea did not appear to further reduce vagal modulation.


Assuntos
Síndromes da Apneia do Sono , Frequência Cardíaca , Hipertensão Pulmonar
9.
Heart ; 105(19): 1471-1478, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31053610

RESUMO

OBJECTIVE: This study sought to determine the prevalence, predictors, prognostic relevance and evolution of pulmonary hypertension (PH) (mean pulmonary artery pressure ≥25 mm Hg) in adult patients with a subaortic right ventricle (RV) in a biventricular circulation (2V-RV). METHODS: We analysed retrospective data from patients with 2V-RV undergoing cardiac catheterisation in our centre between 2000 and 2018. Echocardiographic assessment of subpulmonary ventricular pressures (left ventricular systolic pressure (LVSP)), age and B-type natriuretic peptide (BNP) were assessed as PH screening tools. Kaplan-Meier curves examined time to a composite outcome of death, transplant or ventricular assist device (VAD). Data from repeat catheterisations were analysed to evaluate PH changes over time, including the effects of therapy. RESULTS: A total of 141 patients (median age 39 (IQR 33-45) years, 68% men) underwent 191 cardiac catheterisations. At baseline, 55% had PH (isolated postcapillary 24%, combined precapillary and postcapillary 26% and precapillary 5%). BNP (area under the curve 0.80; 95% CI 0.72 to 0.88; p<0.0001), but not age at catheterisation or echocardiographic estimates of LVSP were associated with the presence of PH. The absence of PH and BNP <100 pg/mL discriminated a subgroup at very low risk during short-term (2.5 (1.3-3.9) years) follow-up (p<0.0001). Diuretics, milrinone and VAD improved haemodynamics over time. CONCLUSION: PH is prevalent in patients with 2V-RV even when asymptomatic. It is difficult to identify by echocardiography and most importantly, is strongly associated with adverse outcomes. PH affects prognosis and transplant options for this patient group and yet is often amenable to treatment. Awareness of these results ought to lower the threshold for invasive haemodynamic assessment and may change the management of failing patients with 2V-RV.


Assuntos
Ventrículos do Coração/anormalidades , Hipertensão Pulmonar/complicações , Adulto , Cateterismo Cardíaco , Ecocardiografia , Feminino , Transplante de Coração/estatística & dados numéricos , Ventrículos do Coração/cirurgia , Coração Auxiliar/estatística & dados numéricos , Humanos , Hipertensão Pulmonar/cirurgia , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Consumo de Oxigênio , Prevalência , Estudos Retrospectivos , Insuficiência da Valva Tricúspide , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/cirurgia
10.
Respirology ; 24(11): 1104-1110, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30963672

RESUMO

BACKGROUND AND OBJECTIVE: Osteopontin (OPN) is a pleiotropic cytokine involved in the proliferation of pulmonary artery smooth muscle cells (PA-SMC). OPN is upregulated in the lungs of patients with pulmonary hypertension (PH) associated with pulmonary fibrosis, suggesting that the lung is a source of OPN. We hypothesized that OPN lung expression is elevated in Group I pulmonary arterial hypertension (PAH) and is correlated to haemodynamics. METHODS: Microarray analysis (Affymetrix) was performed after RNA was extracted from explanted lungs in 15 patients with Group I PAH who underwent lung transplantation (LTx) and 11 normal controls. PA pressure levels were recorded intraoperatively, immediately before starting LTx. Serum OPN levels were measured in subjects with PAH, Group II PH and normal controls on the day of right heart catheterization. RESULTS: OPN was among the top five upregulated genes in PAH compared to normal controls, which was confirmed by reverse transcription polymerase chain reaction (RT-PCR). OPN expression was similar and equally elevated in different subtypes of PAH. A strong significant correlation was observed between mean pulmonary arterial pressure and OPN gene expression. Ingenuity pathway analysis showed the involvement of OPN in functions and networks relevant to angiogenesis, cell death and proliferation of PA-SMC. OPN serum levels did not differ in subjects with Group I PAH and Group II PH. CONCLUSION: In the lungs of patients with severe PAH, OPN is highly expressed and the level of expression is significantly correlated to disease severity. OPN may play an important role in the vascular remodelling process of PAH.


Assuntos
Osteopontina , Hipertensão Arterial Pulmonar , Artéria Pulmonar , Adulto , Biomarcadores/análise , Biomarcadores/metabolismo , Proliferação de Células , Correlação de Dados , Feminino , Expressão Gênica , Humanos , Masculino , Osteopontina/análise , Osteopontina/metabolismo , Análise Serial de Proteínas , Hipertensão Arterial Pulmonar/diagnóstico , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/fisiopatologia , Artéria Pulmonar/metabolismo , Artéria Pulmonar/fisiopatologia , Índice de Gravidade de Doença , Regulação para Cima , Remodelação Vascular
11.
Cardiovasc Res ; 115(1): 222-229, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29878071

RESUMO

Aims: The assumption of equivalence between right ventricular (RV) and pulmonary arterial systolic pressure is fundamental to several assessments of RV or pulmonary vascular haemodynamic function. Our aims were to (i) determine whether systolic pressure gradients develop across the RV outflow tract in healthy adults during exercise, (ii) examine the potential correlates of such gradients, and (iii) consider the effect of such gradients on calculated indices of RV function. Methods and results: Healthy untrained and endurance-trained adult volunteers were studied using right-heart catheterization at rest and during submaximal cycle ergometry. RV and pulmonary artery (PA) pressures were simultaneously transduced, and the cardiac output was determined by thermodilution. Systolic pressures, peak and mean gradients, and indices of chamber, vascular, and valve function were analysed offline. Summary data are reported as mean ± standard deviation or median (interquartile range). No significant RV outflow tract gradients were observed at rest [mean gradient = 4 (3-5) mmHg], and the calculated effective orifice area was 3.6 ± 1.0 cm2. The increase in right ventricular systolic pressure during exercise was greater than the PA systolic pressure. Accordingly, mean gradients were developed during light exercise [8 (7-9) mmHg] and increased during moderate exercise [12 (9-14) mmHg, P < 0.001]. The magnitude of the mean gradient was linearly related to the cardiac output (r2 = 0.70, P < 0.001). Conclusions: In healthy adults without pulmonic stenosis, systolic pressure gradients develop during exercise, and the magnitude is related to the blood flow rate.


Assuntos
Pressão Arterial , Exercício Físico , Artéria Pulmonar/fisiologia , Função Ventricular Direita , Adaptação Fisiológica , Débito Cardíaco , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Circulação Pulmonar , Fatores de Tempo , Resistência Vascular , Pressão Ventricular
12.
Res Pract Thromb Haemost ; 2(4): 670-677, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30349885

RESUMO

Introduction: Risk factors for exercise limitation after acute pulmonary embolism (PE) are unknown. As a planned sub-study of the prospective, multicenter ELOPE (Evaluation of Long-term Outcomes after PE) Study, we aimed to describe the results of serial imaging by computed tomography pulmonary angiography (CTPA) and perfusion scan during 1 year after a first episode of acute pulmonary embolism, and to assess the association between imaging parameters and exercise limitation at 1 year. Methods: In a prospective cohort study, 100 patients were recruited between June 2010 and February 2013 at five Canadian university-affiliated hospitals. CT pulmonary angiography was performed at baseline and 12 months, perfusion scan at 6 and 12 months, and cardio-pulmonary exercise testing at 1 and 12 months. Imaging parameters included: on CT pulmonary angiography, CT obstruction index (CTO) (% clot burden in the pulmonary vasculature), and on perfusion scan, pulmonary vascular obstruction (PVO) (% perfusion defect). Abnormal cardio-pulmonary exercise test (primary outcome) was defined as percent of predicted peak oxygen uptake (VO2) <80%. Results: Mean (median; SD) CT obstruction index was 28.1% (27.5%; 18.3%) at baseline, 1.2% (0%; 4.3%) at 12 months. Mean (median; SD) pulmonary vascular obstruction was 6.0% (0%; 9.6%) at 6 months, 5.6% (0%; 9.8%) at 12 months. Eighty-six patients had exercise testing at 12 months, and 46.5% had VO2 < 80% predicted. Mean (median; SD) CT obstruction index at 1 year was similar in patients with percent-predicted VO2 peak <80% vs >80% on 1-year cardio-pulmonary exercise testing (1.4% [0%; 5.7%] vs 1.0% [0%; 2.4%]; P = .70). Mean (SD) pulmonary vascular obstruction at 6 and at 12 months was similar in patients with percent-predicted VO2 peak <80% vs >80% (6 months: 5.9% [0%; 10.4%] vs 6.2% [4.5%; 9.0%]; P = .91; 12 months: 5.1% [0%; 10.2%] vs 6.0% [0%; 9.7%]; P = .71). Conclusions: Imaging findings after pulmonary embolism did not predict exercise limitation. Residual thrombus does not appear to explain long-term functional limitation after pulmonary embolism.

13.
Lancet ; 391(10140): 2631-2640, 2018 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-30070222

RESUMO

BACKGROUND: Functional capacity is an important component of risk assessment for major surgery. Doctors' clinical subjective assessment of patients' functional capacity has uncertain accuracy. We did a study to compare preoperative subjective assessment with alternative markers of fitness (cardiopulmonary exercise testing [CPET], scores on the Duke Activity Status Index [DASI] questionnaire, and serum N-terminal pro-B-type natriuretic peptide [NT pro-BNP] concentrations) for predicting death or complications after major elective non-cardiac surgery. METHODS: We did a multicentre, international, prospective cohort study at 25 hospitals: five in Canada, seven in the UK, ten in Australia, and three in New Zealand. We recruited adults aged at least 40 years who were scheduled for major non-cardiac surgery and deemed to have one or more risk factors for cardiac complications (eg, a history of heart failure, stroke, or diabetes) or coronary artery disease. Functional capacity was subjectively assessed in units of metabolic equivalents of tasks by the responsible anaesthesiologists in the preoperative assessment clinic, graded as poor (<4), moderate (4-10), or good (>10). All participants also completed the DASI questionnaire, underwent CPET to measure peak oxygen consumption, and had blood tests for measurement of NT pro-BNP concentrations. After surgery, patients had daily electrocardiograms and blood tests to measure troponin and creatinine concentrations until the third postoperative day or hospital discharge. The primary outcome was death or myocardial infarction within 30 days after surgery, assessed in all participants who underwent both CPET and surgery. Prognostic accuracy was assessed using logistic regression, receiver-operating-characteristic curves, and net risk reclassification. FINDINGS: Between March 1, 2013, and March 25, 2016, we included 1401 patients in the study. 28 (2%) of 1401 patients died or had a myocardial infarction within 30 days of surgery. Subjective assessment had 19·2% sensitivity (95% CI 14·2-25) and 94·7% specificity (93·2-95·9) for identifying the inability to attain four metabolic equivalents during CPET. Only DASI scores were associated with predicting the primary outcome (adjusted odds ratio 0·96, 95% CI 0·83-0·99; p=0·03). INTERPRETATION: Subjectively assessed functional capacity should not be used for preoperative risk evaluation. Clinicians could instead consider a measure such as DASI for cardiac risk assessment. FUNDING: Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Ontario Ministry of Health and Long-Term Care, Ontario Ministry of Research, Innovation and Science, UK National Institute of Academic Anaesthesia, UK Clinical Research Collaboration, Australian and New Zealand College of Anaesthetists, and Monash University.


Assuntos
Nível de Saúde , Complicações Pós-Operatórias/etiologia , Idoso , Teste de Esforço , Tolerância ao Exercício , Feminino , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Estudos Prospectivos , Medição de Risco , Sensibilidade e Especificidade
14.
Rheum Dis Clin North Am ; 44(2): 203-213, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29622292

RESUMO

A challenge to the use of observational data to study treatment effects is the issue of confounding. Noncomparability of exposed and nonexposed subjects can lead to biased estimation of the treatment effect. The propensity score is a balancing score that can be used to form matched groups, or pairs, that are not systematically different and enable nonbiased comparisons between groups. This article reviews propensity score methods with an illustrative example of the application of propensity score matching in an observational study of an uncommon disease (systemic sclerosis).


Assuntos
Estudos Observacionais como Assunto/normas , Pontuação de Propensão , Viés , Fatores de Confusão Epidemiológicos , Humanos , Doenças Reumáticas , Resultado do Tratamento
15.
Rheum Dis Clin North Am ; 44(2): 361-370, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29622302

RESUMO

The use of applied Bayesian methods is increasing in rheumatology. Using the Bayes theorem, past evidence is updated with new data. Preexisting data are expressed as a prior probability distribution or prior. New observations are expressed as a likelihood. Through explicit incorporation of preexisting data and new data, this process informs how this new information should change the way we think. In this article, the authors highlight the use of applied Bayesian methods in the study of rheumatic diseases.


Assuntos
Teorema de Bayes , Pesquisa Biomédica , Doenças Reumáticas , Humanos
16.
Chest ; 154(3): 678-690, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29253554

RESUMO

Heparin-induced thrombocytopenia (HIT) is associated with clinically significant morbidity and mortality. Patients who are critically ill are commonly thrombocytopenic and exposed to heparin. Although HIT should be considered, it is not usually the cause of thrombocytopenia in the medical-surgical ICU population. A systematic approach to the patient who is critically ill who has thrombocytopenia according to clinical features, complemented by appropriate laboratory confirmation, should lead to a reduction in inappropriate laboratory testing and reduce the use of more expensive and less reliable anticoagulants. If the patient is deemed as being at intermediate or high risk for HIT or if HIT is confirmed by means of the serotonin-release assay, heparin should be stopped, heparin-bonded catheters should be removed, and a direct antithrombin or fondaparinux should be initiated to reduce the risk of thrombosis. Warfarin is absolutely contraindicated in the acute phase of HIT; if administered, its effects must be reversed by using vitamin K.


Assuntos
Anticoagulantes/efeitos adversos , Estado Terminal , Heparina/efeitos adversos , Trombocitopenia/induzido quimicamente , Humanos
17.
Artigo em Inglês | MEDLINE | ID: mdl-29201389

RESUMO

Background: Dysphagia following prolonged intubation after cardiovascular (CV) surgery is common occurring in 67% of patients; however, this population's swallowing physiology has never been prospectively evaluated using standardized methods. Hence, prior to conducting a larger study, our primary objective was to determine the feasibility of assessing swallowing physiology using instrumentation and validated interpretation methods in cardiovascular surgical patients following prolonged intubation. Method: From July to October 2011, we approached adults undergoing CV surgery at our institution who were intubated > 48 h. Those with a tracheostomy were excluded. Videofluoroscopic swallowing study (VFS) and nasendoscopy were completed within 48 h after extubation. Feasibility measurements included recruitment rate, patient participation, task completion durations, and the inter-rater reliability of VFS measures using the intraclass correlation coefficient (ICC). VFSs were interpreted using perceptual rating tools (Modified Barium Swallow Measurement Tool for Swallow Impairment™© and Penetration Aspiration Scale) and objective displacement measurements (hyoid displacement and pharyngeal constriction ratio). Results: Of the 39 patients intubated > 48 h, 16 met inclusion criteria with three enrolled and completing the VFS. All refused nasendoscopy. Across all VFSs, rating completion time ranged from 14.6 to 51.7 min per patient with ICCs for VFS scales ranging from 0.25 (95% CI - 0.10 to 0.59) to 0.99 (95% CI 0.98 to 0.99). Conclusions: This study design was not feasible as recruitment was slow, few patients participated, and no patient agreed to all procedures. We discuss necessary methodological changes and lessons learned that would generalize to future research.

19.
Am J Med ; 130(8): 990.e9-990.e21, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28400247

RESUMO

BACKGROUND: We aimed to evaluate health-related quality of life (QOL), dyspnea, and functional exercise capacity during the year following the diagnosis of a first episode of pulmonary embolism. METHODS: This was a prospective multicenter cohort study of 100 patients with acute pulmonary embolism recruited at 5 Canadian hospitals from 2010-2013. We measured the outcomes QOL (by Short-Form Health Survey-36 [SF-36] and Pulmonary Embolism Quality of Life [PEmb-QoL] measures), dyspnea (by the University of California San Diego Shortness of Breath Questionnaire [SOBQ]) and 6-minute walk distance at baseline and 1, 3, 6, and 12 months after acute pulmonary embolism. Computed tomography pulmonary angiography was performed at baseline, echocardiogram was performed within 10 days, and cardiopulmonary exercise testing was performed at 1 and 12 months. Predictors of change in QOL, dyspnea, and 6-minute walk distance were assessed by repeated-measures mixed-effects models analysis. RESULTS: Mean age was 50.0 years; 57% were male and 80% were treated as outpatients. Mean scores for all outcomes improved during 1-year follow-up: from baseline to 12 months, mean SF-36 physical component score improved by 8.8 points, SF-36 mental component score by 5.3 points, PEmb-QoL by -32.1 points, and SOBQ by -16.3 points, and 6-minute walk distance improved by 40 m. Independent predictors of reduced improvement over time were female sex, higher body mass index, and percent-predicted VO2 peak <80% on 1 month cardiopulmonary exercise test for all outcomes; prior lung disease and higher pulmonary artery systolic pressure on 10-day echocardiogram for the outcomes SF-36 physical component score and dyspnea score; and higher main pulmonary artery diameter on baseline computed tomography pulmonary angiography for the outcome PEmb-QoL score. CONCLUSIONS: On average, QOL, dyspnea, and walking distance improve during the year after pulmonary embolism. However, a number of clinical and physiological predictors of reduced improvement over time were identified, most notably female sex, higher body mass index, and exercise limitation on 1-month cardiopulmonary exercise test. Our results provide new information on patient-relevant prognosis after pulmonary embolism.


Assuntos
Anticoagulantes/uso terapêutico , Dispneia/etiologia , Tolerância ao Exercício , Embolia Pulmonar/complicações , Qualidade de Vida , Perfil de Impacto da Doença , Caminhada , Adulto , Idoso , Angiografia , Índice de Massa Corporal , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Prognóstico , Estudos Prospectivos , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/tratamento farmacológico , Distribuição por Sexo
20.
Can Respir J ; 2017: 6736239, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28293128

RESUMO

Background. Exhaled nitric oxide (eNO) is a potential biomarker to distinguish systemic sclerosis (SSc) associated pulmonary arterial hypertension (PAH) and interstitial lung disease (ILD). We evaluated the discriminative validity, feasibility, methods of eNO measurement, and magnitude of differences across lung diseases, disease-subsets (SSc, systemic lupus erythematosus), and healthy-controls. Methods. Consecutive subjects in the UHN Pulmonary Hypertension Programme were recruited. Exhaled nitric oxide was measured at 50 mL/s intervals using chemiluminescent detection. Alveolar and conducting airway NO were partitioned using a two-compartment model of axial diffusion (CMAD) and the trumpet model of axial diffusion (TMAD). Results. Sixty subjects were evaluated. Using the CMAD model, control subjects had lower median (IQR) alveolar NO than all PAH subjects (2.0 (1.5, 2.5) versus 3.14 ppb (2.3, 4.0), p = 0.008). SSc-ILD had significantly lower median conducting airway NO compared to controls (1009.5 versus 1342.1 ml⁎ppb/s, p = 0.04). SSc-PAH had increased median (IQR) alveolar NO compared to controls (3.3 (3.0, 5.7) versus 2.0 ppb (1.5, 2.5), p = 0.01). SSc-PAH conducting airway NO inversely correlated with DLCO (r -0.88 (95% CI -0.99, -0.26)). Conclusion. We have demonstrated feasibility, identified that CMAD modeling is preferred in SSc, and reported the magnitude of differences across cases and controls. Our data supports discriminative validity of eNO in SSc lung disease.


Assuntos
Pneumopatias/metabolismo , Óxido Nítrico/metabolismo , Escleroderma Sistêmico/metabolismo , Adulto , Testes Respiratórios , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...