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1.
Ann Card Anaesth ; 25(3): 335-342, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35799563

RESUMO

Background: An ideal CO monitor should be noninvasive, cost effective, reproducible, reliable during various physiological states. Limited literature is available regarding the noninvasive CO monitoring in open chest surgeries. Aim: The aim of this study was to compare the CO measurement by Regional Impedance Cardiography (RIC) and Thermodilution (TD) method in patients undergoing off pump coronary artery bypass graft surgery (OPCAB). Settings and Design: We conducted a prospective observational comparative study of CO measurement by the noninvasive RIC method using the NICaS Hemodynamic Navigator system and the gold standard TD method using pulmonary artery catheter in patients undergoing OPCAB. A total of 150 data pair from the two CO monitoring techniques were taken from 15 patients between 40-70 years at various predefined time intervals of the surgery. Patients and Methods: We have tried to find out the accuracy, precision and cost effectiveness of the newer RIC technique. Mean CO, bias and precision were compared for each pair i.e.TD-CO and RIC-CO as recommended by Bland and Altman. The Sensitivity and specificity of cutoff value to predict change in TD-CO was used to create a Receiver operating characteristic or ROC curve. Results: Mean TD-CO values were around 4.52 ± 1.09 L/min, while mean RIC- CO values were around 4.77± 1.84 L/min. The difference in CO change was found to be statistically not significant (p value 0.667). The bias was small (-0.25). The Bland Altman plot revealed a mean difference of -0.25 litres. The RIC method had a sensitivity of 55.56 % and specificity of 33.33 % in predicting 15% change in CO of TD method and the total diagnostic accuracy was 46.67%. Conclusion: A fair correlation was found between the two techniques. The RIC method may be considered as a promising noninvasive, potentially low cost alternative to the TD technique of hemodynamic measurement.


Assuntos
Cardiografia de Impedância , Ponte de Artéria Coronária sem Circulação Extracorpórea , Débito Cardíaco/fisiologia , Cardiografia de Impedância/métodos , Cateterismo de Swan-Ganz , Humanos , Reprodutibilidade dos Testes , Termodiluição/métodos
2.
Int J Gen Med ; 15: 6043-6053, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35818582

RESUMO

Purpose: The aim of this study was to use non-invasive impedance cardiography (ICG) to determine the hemodynamic status of patients with grade 1 and grade 2 hypertension in relation to gender and age. Patients and Methods: We analyse prospectively collected data of 158 patients with grade 1 or grade 2 arterial hypertension. Patients were grouped according to age: 1) <50 years and 2) ≥50 years. Hemodynamic status of patients was assessed by using non-invasive ICG. For the purpose of this study two hemodynamic parameters were used: a) systemic vascular resistance index (SVRI) and b) left cardiac work index (LCWI). The primary endpoint was the hemodynamic status of patients. The secondary endpoint was hypertension-mediated organ damage. Results: Increased SVRI was assessed in 80% of patients, more common in the ≥50 years group than in the <50 years group (88.5% vs 64.8%; p < 0.01). The occurrence of increased systemic vascular resistance correlates hierarchically with increasing age. Elevated LCWI (hypervolemia and/or hyperinotropy) was present in 63% of patients, more often in males than females (70.3% vs 57.1%; p < 0.05) as well in those <50 years than in older patients (70.4% vs 59.6%; p < 0.05). Patients with diabetes were less likely to have hypervolemia/hyperinotropy than those without diabetes (46.7% vs 67.2%; p < 0.01). Hypervolemia/hyperinotropy (46.7%) and hypovolemia/hypoinotropy (43.3%) were present in a similar percentage of diabetic patients. Left ventricular hypertrophy was found in 30 patients (19%). Patients with left ventricular hypertrophy were more commonly male (66.7% vs 42.2%; p = 0.016) and had increased systemic vascular resistance (96.7% vs 77.3%; p = 0.015) compared to the patients without left ventricular hypertrophy. Hypertensive retinopathy grade III was found in 14 patients (8.9%). Elevated daytime systolic pressure, diabetes and increased age are independent predictors of grade III hypertensive retinopathy. Patients with reduced renal function had higher mean systolic blood pressure (p < 0.05), were more commonly male (p < 0.01) and older (p < 0.01) than those without reduced renal function. Conclusion: Although there are certain correlations between hemodynamic disorders and age and gender, specific hemodynamic status of an individual patient with hypertension cannot reliably be predicted on the basis of age and gender. The measurement of hemodynamic parameters by ICG can guide the clinician to select appropriate antihypertensive therapy to the patients' hemodynamic pathophysiologic condition.

3.
Ann Agric Environ Med ; 29(2): 264-268, 2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35767761

RESUMO

INTRODUCTION AND OBJECTIVE: Difficult-to-control blood pressure can be attributed to a mismatch between the haemodynamic type of hypertension and the drug class used in treatment. Impedance cardiography may be a useful tool for enabling the individualization of antihypertensive therapy. The aim was to investigate the distribution of haemodynamic types of HT among hypertensive patients in an outpatient clinic. MATERIAL AND METHODS: This was a prospective, observational study of patients with primary hypertension at an outpatient clinic. A 10-minute ICG examination was performed in 189 consecutive, patients (118 men and 71 women). Patients were divided into groups based on whether their hypertension was well-controlled (140/90 mmHg, n=95). They were also stratified according to haemodynamic states. RESULTS: Patients with poorly controlled blood pressure compared to patients with well controlled blood pressure had a high haemodynamic output in 6.3% vs. 2.1% (p=0.153), and high vascular resistance in 41.1% vs. 27.7% (p=0.037), and balanced haemodynamic states in 52.6% vs. 70.2% (0 80 beats/min) and fluid retention (p<0.01). CONCLUSIONS: Half of the examined patients did not achieve the therapeutic goals for hypertension treatment. Differences in haemodynamic state of well and poor controlled hypertension groups suggests the usefulness of impedance cardiography-targeted hypertension treatment.


Assuntos
Hipertensão , Pressão Sanguínea , Cardiografia de Impedância , Feminino , Hemodinâmica , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Masculino , Estudos Prospectivos
4.
Psychophysiology ; 59(9): e14061, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35363387

RESUMO

Partner support for self-expansion has been associated with long-term health and retirement satisfaction, yet the underlying physiological correlates are unknown. We predicted that partner support for self-expansion would be associated with short-term physiology and behavior as well as long-term goal pursuit. And 100 couples with at least one retiree within 2 years of retirement visited the laboratory and had a discussion of the retirees' future goals for retirement. We recorded behaviors and physiological responses during the discussion, assessed immediate feelings of capability afterwards, and then assessed goal pursuit one year later. Laboratory results indicated that partner support for self-expansion was linked to increased stroke volume reactivity in the support-recipient (suggesting a greater challenge response), which in turn predicted greater feelings of capability of accomplishing the goal, particularly for males. In addition, decreases in the support-provider's pre-ejection period reactivity (greater sympathetic arousal) during the discussion were associated with greater partner support for self-expansion in the lab, suggesting that support providers offer greater levels of support when they exhibit greater physiological signs of task engagement. Longitudinal follow-up results indicated that immediate feelings of capability of accomplishing the goal following a discussion about that goal predicted goal pursuit 1 year later. This research leverages a dyadic design and a multi-method approach (involving physiology, observed behavior, and perceptions) to show that couple members' physiology during goal discussions has long-term implications for a support-recipient's ability to accomplish goals.


Assuntos
Objetivos , Aposentadoria , Emoções , Humanos , Masculino , Satisfação Pessoal
5.
Pregnancy Hypertens ; 28: 123-127, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35339775

RESUMO

OBJECTIVES: We sought to determine the effect of impedance cardiography directed medical antihypertensive therapy on fetal growth restriction and perinatal mortality in women with chronic hypertension. STUDY DESIGN: A retrospective study was conducted on 958 women referred to the Maternal Hypertension Center at Cabell Huntington Hospital between 2005 and 2014 for the indication of chronic hypertension. MAIN OUTCOME MEASURES: Serial assessments of maternal hemodynamics were obtained using non-invasive impedance cardiography. Vasodilators were initiated for increased systemic vascular resistance. Elevated cardiac output was treated with beta blockade. RESULTS: Blood pressure at initial visit was used to stratify patients into five groups. Initial blood pressure of <130 systolic or <80 diastolic had 24 cases of growth restriction (6.8%) and 6 perinatal deaths (1.7%), 130-139 systolic or 80-89 diastolic resulted in 29 cases of growth restriction (9.3%) and 9 perinatal deaths (2.9%), 140-149 systolic or 90-99 diastolic 14 cases of growth restriction (6.5%) and 3 perinatal deaths (1.4%), 150-159 systolic or 100-109 diastolic had 5 cases of growth restriction (8.6%) and 4 perinatal deaths (6.89%), and >160 systolic or >110 diastolic 3 cases of growth restriction (13%) with no perinatal deaths. There were no differences in growth restriction (p = .59) or perinatal death (p = .15) between the groups. CONCLUSION: The rates of IUGR and perinatal mortality did not increase even with increasing severity of maternal hypertension. This low cost and non-invasive test should be considered for optimizing rates of growth restriction and perinatal mortality in pregnancies complicated by chronic hypertension.


Assuntos
Hipertensão , Morte Perinatal , Pré-Eclâmpsia , Anti-Hipertensivos/uso terapêutico , Cardiografia de Impedância , Feminino , Retardo do Crescimento Fetal , Humanos , Mortalidade Perinatal , Gravidez , Estudos Retrospectivos
6.
J Med Eng Technol ; 46(4): 280-287, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35212589

RESUMO

Impedance cardiography (IC) is a non-invasive method for assessing cardiovascular hemodynamics, and has been utilised during exercise, exclusively on a cycle ergometer. Mode-specific differences in cardiovascular hemodynamics during exercise have previously been identified, but the ability of IC to identify these differences has not been explored. Therefore, we examined the repeatability of cardiovascular hemodynamics within and between exercise modes on the treadmill (TM) and cycle (CY) ergometer. Twenty-one men (age = 21.4 ± 0.5 yr) performed four maximal exercise, two TM and two CY. Within each test, two, five-minute stages were completed corresponding to moderate and vigorous exercise intensities, respectively. Oxygen consumption (VO2) was measured continuously during each test. Hemodynamic measures were obtained via IC, and included cardiac output (CO), heart rate (HR), stroke volume (SV), end diastolic volume (EDV), ejection fraction (EF), and systemic vascular resistance (SVR). Repeated measures ANOVA revealed that within TM exercise, there was a main effect for trial with HR only. There were no main effects for trial within CY exercise. Across exercise modes, there were significant main effects for mode with HR, EDV, and SVR. CY exercise resulted in a higher HR, lower SV and EDV, consistent with previous findings, utilising more criterion and invasive methods. Results suggest that hemodynamics, as assessed by IC, are repeatable within TM and CY exercise. In addition, it appears as though IC is capable of detecting mode-specific differences in hemodynamics, suggesting IC to be a useful assessment tool during exercise.


Assuntos
Cardiografia de Impedância , Teste de Esforço , Adulto , Débito Cardíaco/fisiologia , Frequência Cardíaca , Hemodinâmica/fisiologia , Humanos , Masculino , Volume Sistólico/fisiologia , Adulto Jovem
7.
Psychophysiology ; 59(7): e14013, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35150459

RESUMO

Pre-ejection period (PEP) is an index of sympathetic nervous system activity that can be computed from electrocardiogram (ECG) and impedance cardiogram (ICG) signals, but sensitive to speech/motion artifact. We sought to validate an ICG noise removal method, three-stage ensemble-average algorithm (TEA), in data acquired from a clinical trial comparing active versus sham non-invasive vagal nerve stimulation (tcVNS) after standardized speech stress. We first compared TEA's performance versus the standard conventional ensemble-average algorithm (CEA) approach to classify noisy ICG segments. We then analyzed ECG and ICG data to measure PEP and compared group-level differences in stress states with each approach. We evaluated 45 individuals, of whom 23 had post-traumatic stress disorder (PTSD). We found that the TEA approach identified artifact-corrupted beats with intraclass correlation coefficient > 0.99 compared to expert adjudication. TEA also resulted in higher group-level differences in PEP between stress states than CEA. PEP values were lower in the speech stress (vs. baseline rest) group using both techniques, but the differences were greater using TEA (12.1 ms) than CEA (8.0 ms). PEP differences in groups divided by PTSD status and tcVNS (active vs. sham) were also greater when using the TEA versus CEA method, although the magnitude of the differences was lower. In conclusion, TEA helps to accurately identify noisy ICG beats during speaking stress, and this increased accuracy improves sensitivity to group-level differences in stress states compared to CEA, suggesting greater clinical utility.


Assuntos
Antígeno Carcinoembrionário , Cardiografia de Impedância , Algoritmos , Artefatos , Cardiografia de Impedância/métodos , Eletrocardiografia , Humanos
8.
J Clin Med ; 11(3)2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35160276

RESUMO

Fasting prior to surgery can cause dehydration and alter hemodynamics. This study aimed to determine the impact of a carbohydrate-enriched drink (NutriciaTM Pre-op®) on selected hemodynamical parameters, measured in a non-invasive manner. We enrolled 100 healthy volunteers and measured their weight, height, systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), thoracic fluid content (TFC), thoracic fluid index (TFCI), stroke volume (SV), stroke volume variation (SVV), stroke index (SI), cardiac output (CO), cardiac index (CI), heather index (HI), systolic time ration (STR), systemic time ratio index (STRI), systemic vascular resistance (SVR), and systemic vascular resistance index (SVRI) by a Niccomo™ device, implementing the impedance cardiography (ICG) method. Measurements were performed at the beginning of the study, and after 10 h and 12 h. We randomly allocated participants to the control group and the pre-op group. The pre-op group received 400 mL of Nutricia™ preOp®, as suggested in the ERAS guidelines, within 10 h of the study. Student's t-test or the Mann-Whitney U test were used to compare the two groups, and p < 0.05 was considered significant. We did not observe any changes in hemodynamical parameters, blood pressure, and heart rate between the groups. We have proven that carbohydrate-enriched drink administration did not have a significant impact on the hemodynamical parameters of healthy volunteers.

9.
Am J Obstet Gynecol ; 226(2S): S988-S1005, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35177225

RESUMO

Gestational hypertension and preeclampsia are the 2 main types of hypertensive disorders in pregnancy. Noninvasive maternal cardiovascular function assessment, which helps obtain information from all the components of circulation, has shown that venous hemodynamic dysfunction is a feature of preeclampsia but not of gestational hypertension. Venous congestion is a known cause of organ dysfunction, but its potential role in the pathophysiology of preeclampsia is currently poorly investigated. Body water volume expansion occurs in both gestational hypertension and preeclampsia, and this is associated with the common feature of new-onset hypertension after 20 weeks of gestation. Blood pressure, by definition, is the product of intravascular volume load and vascular resistance (Ohm's law). Fundamentally, hypertension may present as a spectrum of cardiovascular states varying between 2 extremes: one with a predominance of raised cardiac output and the other with a predominance of increased total peripheral resistance. In clinical practice, however, this bipolar nature of hypertension is rarely considered, despite the important implications for screening, prevention, management, and monitoring of disease. This review summarizes the evidence of type-specific hemodynamic profiles in the latent and clinical stages of hypertensive disorders in pregnancy. Gestational volume expansion superimposed on an early gestational closed circulatory circuit in a pressure- or volume-overloaded condition predisposes a patient to the gradual deterioration of overall circulatory function, finally presenting as gestational hypertension or preeclampsia-the latter when venous dysfunction is involved. The eventual phenotype of hypertensive disorder is already predictable from early gestation onward, on the condition of including information from all the major components of circulation into the maternal cardiovascular assessment: the heart, central and peripheral arteries, conductive and capacitance veins, and body water content. The relevance of this approach, outlined in this review, openly invites for more in-depth research into the fundamental hemodynamics of gestational hypertensive disorders, not only from the perspective of the physiologist or the scientist, but also in assistance of clinicians toward understanding and managing effectively these severe complications of pregnancy.


Assuntos
Hemodinâmica/fisiologia , Hipertensão Induzida pela Gravidez/fisiopatologia , Pré-Eclâmpsia/fisiopatologia , Técnicas de Diagnóstico Cardiovascular , Feminino , Humanos , Placentação/fisiologia , Volume Plasmático/fisiologia , Gravidez , Resistência Vascular/fisiologia
11.
J Med Eng Technol ; 46(3): 243-260, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35040738

RESUMO

Over the last decade, Computer-Aided Diagnosis (CAD) systems have been provided significant research focus by researchers. CAD systems have been developed in order to minimise visual errors, to compensate manual interpretation, and to help medical staff to take decisions swiftly. These systems have been considered as powerful tools for a reliable, automatic, and low-cost monitoring and diagnosis. CAD systems are based on analysis and classification of several physiological signals for detecting and assessing different diseases related to the corresponding organ. The implementation of these systems requires the application of several advanced signal processing techniques. Specifically, in cardiology, CAD systems have achieved promising results in providing an accurate and rapid detection of cardiovascular diseases (CVDs). Particularly, the number of works on signal processing field for impedance cardiography (ICG) signals starts to grow slowly in recent years. This paper presents a review study of signal processing techniques applied to the ICG signal for the denoising, the analysis, the classification and the characterisation purposes. This review is intended to provide researchers with a broad overview of the currently used signal processing techniques for ICG signal analysis, as well as to improve future research by applying other recent advanced methods.


Assuntos
Cardiografia de Impedância , Processamento de Sinais Assistido por Computador , Cardiografia de Impedância/métodos , Diagnóstico por Computador , Humanos
12.
J Med Eng Technol ; 46(2): 116-128, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34882056

RESUMO

Cardiac Output (CO) is a significant hemodynamic index for the diagnosis and treatment of cardiovascular diseases. Impedance cardiography (ICG) is one of the non-invasive methods widely investigated for its simplicity, cost-effectiveness and ability to measure cardiac output continuously. However, measured ICG signals are contaminated by the respiratory artefact leading to difficulties in determining characteristic points in the signal waveform, thereby lowering the accuracy of measurement results. Thus, suppressing this artefact plays an important role in ICG signal processing. This paper aims to propose a method of noise filtering to improve the quality of the signal as well as a model to evaluate the noise filtering efficiency of the method. The proposed algorithm showed promising results with the output SNR values of 21.99 ± 3.20 dB, 20.40 ± 2.88 dB, 15.57 ± 4.79 dB for normal breathing, forced breathing, and rapid breathing respectively. The root mean square percentage error (RMSPE) values of the output signals processed by the proposed algorithm compared to the standard ICG signal source for normal breathing, forced breathing, and rapid breathing are 24.13 ± 22.66%, 18.09 ± 12.98%, 32.13 ± 20.40% respectively. The quality-enhanced ICG signal could be effective tool for assisting doctors to detect cardiac abnormalities via evaluating the morphology of ICG signal waveforms as well as improving accuracy in calculating beat-to-beat and averaged hemodynamic parameters.


Assuntos
Cardiografia de Impedância , Processamento de Sinais Assistido por Computador , Débito Cardíaco , Hemodinâmica , Taxa Respiratória
13.
Psychophysiology ; 59(2): e13955, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34665890

RESUMO

Cannabis is the most commonly used psychotropic drug in the United States, after alcohol. Despite its apparent sedative and calming effects, cannabis and its main psychoactive constituent, ∆9 -tetrahydrocannabinol (THC) can produce serious adverse effects including tachycardia and anxiety. These effects can be especially pronounced in women, who remain underrepresented in clinical cannabinoid research. The present study is one of the first to characterize the effects of single doses of oral THC on autonomic nervous system function in healthy adult women. Occasional female cannabis users participated in three laboratory sessions in which they received oral THC (7.5 and 15 mg) and placebo. Autonomic measures included heart rate (HR), blood pressure (BP), pre-ejection period (PEP) a measure of cardiac sympathetic functioning, and high frequency heart rate variability (HF-HRV) a measure of parasympathetic cardiac control. Autonomic responses were examined in relation to subjective drug effects. THC dose-dependently increased HR, decreased HF-HRV, and increased ratings of feeling a drug effect, cannabis-like intoxication, and anxiety. Although the drug did not significantly affect BP or PEP, HR was negatively related to both PEP and HF-HRV. HF-HRV, the measure of parasympathetic activity, was significantly negatively related to subjective measures of cannabis intoxication (but not anxiety) at the 15 mg dose only. PEP was not significantly related to any subjective measure. These results extend our knowledge of the autonomic effects of THC in relation to subjective drug experience. This and future studies will help us to understand risk factors related to cannabis use.


Assuntos
Ansiedade/induzido quimicamente , Pressão Sanguínea/efeitos dos fármacos , Agonistas de Receptores de Canabinoides/farmacologia , Dronabinol/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Sistema Nervoso Parassimpático/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Administração Oral , Adulto , Agonistas de Receptores de Canabinoides/administração & dosagem , Agonistas de Receptores de Canabinoides/efeitos adversos , Dronabinol/administração & dosagem , Dronabinol/efeitos adversos , Feminino , Humanos , Adulto Jovem
14.
Front Cardiovasc Med ; 8: 744349, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34881303

RESUMO

Vascular dysfunction is a key hallmark of hypertension and related cardiovascular outcomes. As a well-known hemodynamic disease, hypertension is characterized by abnormal ventricular-vascular interactions. Complementing non-invasive systemic hemodynamics in hypertensive vascular risk assessment is of promising significance. We aimed to investigate the effects of abnormal hemodynamic states other than elevated blood pressure on vascular damage and establish a united index of systemic hemodynamics for generalized vascular risk evaluation. Non-invasive systemic hemodynamics, assessed by impedance cardiography, was compared among blood pressure stages. Vascular function was evaluated by flow-mediated dilation (FMD) and brachial-ankle pulse wave velocity (baPWV). Systemic hemodynamics was obtained from a total of 88 enrollees with a mean (±SD) systolic blood pressure 140 (±17) mm Hg, and aged 17 to 91 years. Both stroke systemic vascular resistance index and left stroke work index exhibited a significant alteration among blood pressure stages (p < 0.001; p = 0.01, respectively), whereas heterogeneous hemodynamic and vascular function subsets existed within similar blood pressure. In addition, blood pressure categories failed to recognize between-group differences in endothelial dysfunction (p = 0.88) and arterial stiffness (p = 0.26). An increase in myocardial contractility and a parallel decrease in afterload was associated with the decline of vascular dysfunction. Systemic Hemodynamic Index (SHI), as a surrogate marker, demonstrated a significantly negative correlation with vascular damage index (VDI, r = -0.49, p < 0.001). These findings illustrate that systemic hemodynamics underlying hypertensives provides more vascular information. The SHI/VDI score may be a feasible tool for cardiovascular function assessment.

15.
Entropy (Basel) ; 23(12)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34945967

RESUMO

An aortic dissection, a particular aortic pathology, occurs when blood pushes through a tear between the layers of the aorta and forms a so-called false lumen. Aortic dissection has a low incidence compared to other diseases, but a relatively high mortality that increases with disease progression. An early identification and treatment increases patients' chances of survival. State-of-the-art medical imaging techniques have several disadvantages; therefore, we propose the detection of aortic dissections through their signatures in impedance cardiography signals. These signatures arise due to pathological blood flow characteristics and a blood conductivity that strongly depends on the flow field, i.e., the proposed method is, in principle, applicable to any aortic pathology that changes the blood flow characteristics. For the signal classification, we trained a convolutional neural network (CNN) with artificial impedance cardiography data based on a simulation model for a healthy virtual patient and a virtual patient with an aortic dissection. The network architecture was tailored to a multi-sensor, multi-channel time-series classification with a categorical cross-entropy loss function as the training objective. The trained network typically yielded a specificity of (93.9±0.1)% and a sensitivity of (97.5±0.1)%. A study of the accuracy as a function of the size of an aortic dissection yielded better results for a small false lumen with larger noise, which emphasizes the question of the feasibility of detecting aortic dissections in an early state.

16.
Front Pediatr ; 9: 729824, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34966699

RESUMO

Introduction: Pompe disease is caused by deficiency of the lysosomal enzyme acid α-glucosidase, which results in cardiac and muscular complications that can jeopardize perioperative outcomes. We report a 4-month-old infant with Pompe disease receiving cheiloplasty under general anesthesia with the aid of peripheral nerve blocks and intensive hemodynamic monitoring. Case Description: This case report describes a 4-month-old full-term Taiwanese female infant who presented with left unilateral cleft lip and palate in the prenatal examination. She was diagnosed with infantile-onset Pompe disease after acidic α-glucosidase (GAA) gene sequencing. She also received enzyme replacement therapy (ERT) 15 days after birth and regular ERT every other week. Cheiloplasty was performed under general anesthesia uneventfully, and peripheral nerve blocks were adopted for analgesia. Intensive hemodynamic monitoring using electrical cardiometry technology (ICON®) and pulse contour analysis (FloTrac system) were applied during the operation. No adverse effects were observed, and the wound healed well. Therefore, the patient was discharged 4 days after surgery. Conclusion: With the availability of ERT, severe organ dysfunction in infantile-onset Pompe disease patients is no longer common. However, moderate cardiac depression can still occur while increasing inspiratory pressure and deepening the anesthesia level despite a normal preoperative echocardiogram report. Therefore, careful, gradual titration is desirable. Furthermore, electrical cardiometry can detect hemodynamic changes more instantaneously and reliably than pulse contour analysis. In addition, we suggest taking advantage of the peripheral nerve block as a part of balanced anesthesia to alleviate the cardiac suppression caused by general anesthesia.

17.
Front Endocrinol (Lausanne) ; 12: 751743, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659130

RESUMO

Background: Cushing's disease is a rare condition associated with a high cardiovascular risk and hypercortisolemia-related hemodynamic dysfunction, the extent of which can be assessed with a noninvasive method, called impedance cardiography. The standard methods for hemodynamic assessment, such as echocardiography or ambulatory blood pressure monitoring may be insufficient to fully evaluate patients with Cushing's disease; therefore, impedance cardiography is being currently considered a new modality for assessing early hemodynamic dysfunction in this patient population. The use of impedance cardiography for diagnosis and treatment of Cushing's disease may serve as personalized noninvasive hemodynamic status assessment and provide a better insight into the pathophysiology of Cushing's disease. The purpose of this study was to assess the hemodynamic profile of Cushing's disease patients and compare it with that in the control group. Material and Methods: This observational prospective clinical study aimed to compare 54 patients with Cushing's disease (mean age 41 years; with 64.8% of this population affected with arterial hypertension) and a matched 54-person control group (mean age 45 years; with 74.1% of this population affected with arterial hypertension). The hemodynamic parameters assessed with impedance cardiography included the stroke index (SI), cardiac index (CI), systemic vascular resistance index (SVRI), velocity index (VI), (ACI), Heather index (HI), and thoracic fluid content (TFC). Results: The Cushing's disease group was characterized by a higher diastolic blood pressure and a younger age than the control group (82.9 vs. 79.1 mmHg, p=0.045; and 41.1 vs. 44.9 years, p=0.035, respectively). Impedance cardiography parameters in the Cushing's disease group showed: lower values of SI (42.1 vs. 52.8 ml/m2; p ≤ 0.0001), CI (2.99 vs. 3.64 l/min/m2; p ≤ 0,0001), VI (42.9 vs. 52.1 1/1000/s; p=0.001), ACI (68.7 vs. 80.5 1/100/s2; p=0,037), HI (13.1 vs. 15.2 Ohm/s2; p=0.033), and TFC (25.5 vs. 27.7 1/kOhm; p=0.006) and a higher SVRI (2,515 vs. 1,893 dyn*s*cm-5*m2; p ≤ 0.0001) than those in the control group. Conclusions: Cushing's disease is associated with significantly greater vasoconstriction and left ventricular systolic dysfunction. An individual assessment with impedance cardiography may be useful in Cushing's disease patients in order to identify subclinical cardiovascular complications of chronic hypercortisolemia as potential therapeutic targets.


Assuntos
Cardiografia de Impedância/métodos , Hemodinâmica , Hipersecreção Hipofisária de ACTH/diagnóstico , Adulto , Envelhecimento , Pressão Sanguínea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hipersecreção Hipofisária de ACTH/fisiopatologia , Estudos Prospectivos , Vasoconstrição , Disfunção Ventricular Esquerda , Função Ventricular Esquerda , Equilíbrio Hidroeletrolítico
18.
Physiol Meas ; 42(10)2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34547725

RESUMO

Objective.Breast cancer treatment can negatively impact cardiac function in some breast cancer patients. Current methods (MUGA, echocardiography) used in clinical practice to detect abnormal cardiac changes as a result of treatment suffer from important limitations. Use of alternative techniques that would offer safe, inexpensive and non-invasive cardiac function assessment in this population would be highly advantageous. The aim of this study was to examine the agreement between impedance cardiography (ICG) and cardiac magnetic resonance imaging (CMR) in quantifying stroke volume (SV), cardiac output (CO) and end-diastolic volume (EDV) in this population.Approach.Sixteen breast cancer patients underwent ICG and CMR assessments at three time-points (before treatment, immediately after chemotherapy, and four months after chemotherapy). Bland-Altman analysis was used to quantify the accuracy and precision of ICG (relative to CMR) in estimating absolute values of SV, CO and EDV. Four methods (concordance rate, polar concordance rate, clinical concordance rate and trend interchangeability rate) were also used to assess ICG performance in tracking changes in these variables.Main results.Bland-Altman analysis showed that the accuracy of ICG relative to CMR was -3.1 ml (SV), 0.2 l·min-1(CO) and -26.0 ml (EDV) and precision was 13.2 ml (SV), 1.1 l·min-1(CO) and 20.1 ml (EDV), respectively. Trending ability assessment showed that (1) the concordance rate was 87% (SV), 73% (CO) and 73% (EDV), (2) the polar concordance rate was 67% (SV), 53% (CO) and 33% (EDV), (3) the clinical concordance rate was 33% (SV), 40% (CO) and 20% (EDV) and (4) the trend interchangeability rate was 29% (SV), 43% (CO) and 17% (EDV), respectively.Significance.Our findings show that, although ICG showed good accuracy for absolute SV and CO measurements and for CO and EDV changes, precision was poor for all variables in terms of both absolute measurements and trend tracking performance. This suggests that ICG cannot be used interchangeably with CMR in breast cancer patients.


Assuntos
Neoplasias da Mama , Cardiografia de Impedância , Neoplasias da Mama/diagnóstico por imagem , Débito Cardíaco , Feminino , Humanos , Imageamento por Ressonância Magnética , Volume Sistólico
19.
Physiol Meas ; 42(9)2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34433135

RESUMO

Objective. Impedance cardiography (ICG) is a noninvasive and continuous method for evaluating stroke volume and cardiac output. However, the ICG measurement is easily interfered due to respiration and body movements. Taking into consideration about the spectral correlations between the simultaneously collected ICG, electrocardiogram (ECG), and acceleration signals, this paper introduces a two-step spectrum denoising method to remove motion artifacts of ICG measurements in both resting and exercising scenarios.Approach. First, the major motion artifacts of ECG and ICG are separately suppressed by the spectral subtraction with respect to acceleration signals. The obtained ECG and ICG are further decomposed into two sets of intrinsic mode functions (IMFs) through the ensemble empirical mode decomposition. We then extract the shared spectral information between the two sets of IMFs using the canonical correlation analysis in a spectral domain. Finally, the ICG signal is reconstructed using those canonical variates with largest spectral correlations with ECG IMFs.Main results. The denoising method was evaluated for 30 subjects under both resting and cycling scenarios. Experimental results show that the beat contribution factor of ICG signals increases from its original 80.1%-97.4% after removing the motion artifacts.Significance. The proposed denoising scheme effectively improves the reliability of diagnosis and analysis on cardiovascular diseases relying on ICG signals.


Assuntos
Cardiografia de Impedância , Processamento de Sinais Assistido por Computador , Algoritmos , Eletrocardiografia , Humanos , Reprodutibilidade dos Testes
20.
IEEE Open J Eng Med Biol ; 2: 210-217, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34458855

RESUMO

OBJECTIVE: Bioimpedance sensing is a powerful technique that measures the tissue impedance and captures important physiological parameters including blood flow, lung movements, muscle contractions, body fluid shifts, and other cardiovascular parameters. This paper presents a comprehensive analysis of the modality at different arterial (ulnar, radial, tibial, and carotid arteries) and thoracic (side-rib cage and top thoracolumbar fascia) body regions and offers insights into the effectiveness of capturing various cardiac and respiratory activities. METHODS: We assess the bioimpedance performance in estimating inter-beat (IBI) and inter -breath intervals (IBrI) on six-hours of data acquired in a pilot-study from five healthy participants at rest. RESULTS: Overall, we achieve mean errors as low as 0.003 ± 0.002 and 0.67 ± 0.28 seconds for IBI and IBrI estimations, respectively. CONCLUSIONS: The results show that bioimpedance can be effectively used to monitor cardiac and respiratory activities both at limbs and upper body and demonstrate a strong potential to be adopted by wearables that aim to provide high-fidelity physiological sensing to address precision medicine needs.

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