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1.
IEEE Open J Eng Med Biol ; 5: 198-204, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606401

RESUMO

OBJECTIVE: This study addressed the problem of objectively detecting leaks in P2 respirators at point of use, an essential component for healthcare workers' protection. To achieve this, we explored the use of infra-red (IR) imaging combined with machine learning algorithms on the thermal gradient across the respirator during inhalation. RESULTS: The study achieved high accuracy in predicting pass or fail outcomes of quantitative fit tests for flat-fold P2 FFRs. The IR imaging methods surpassed the limitations of self fit-checking. CONCLUSIONS: The integration of machine learning and IR imaging on the respirator itself demonstrates promise as a more reliable alternative for ensuring the proper fit of P2 respirators. This innovative approach opens new avenues for technology application in occupational hygiene and emphasizes the need for further validation across diverse respirator styles. SIGNIFICANCE STATEMENT: Our novel approach leveraging infra-red imaging and machine learning to detect P2 respirator leaks represents a critical advancement in occupational safety and healthcare workers' protection.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38654418

RESUMO

BACKGROUND: Real-time signal processing has to date been difficult to implement in the clinical electrophysiology laboratory. To date, no open access software solutions are available in electrophysiology (EP) laboratories to facilitate real-time intraprocedural signal analysis. We aimed to develop an open access, scalable Python plug-in to allow real-time signal processing during human EP procedures. METHODS AND RESULTS: A Python-based plug in for the widely available EnsiteX mapping system was developed. This plug-in utilized the LiveSync feature of the system to allow real-time signal analysis. An open access library was developed to allow end-users to implement real-time signal analysis using this platform, implemented in the Python programming language https://github.com/anand9176/WaveWatch5000Public. CONCLUSION: We have developed and demonstrated the feasibility of a readily scalable and open-access Python-based plug in to an electroanatomic mapping system (EnSiteX) to allow real-time processing and display of electrogram (EGM) based information for the procedural electrophysiologist to view intraprocedurally in the electrophysiology laboratory. The availability, to the clinician, of traditional and novel EGM-based metrics at the time of intervention, such as atrial fibrillation ablation, allows for key mechanistic insights into critical unresolved questions regarding arrhythmia mechanism.

3.
JACC Clin Electrophysiol ; 10(2): 306-315, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38206259

RESUMO

BACKGROUND: Conduction system pacing (CSP) faces challenges in achieving reliable and safe deployments. Complex interactions between tissue and lead tip can result in endocardial entanglement, a drill effect that prevents penetration. No verified ex vivo model exists to quantitatively assess this relationship. OBJECTIVES: The purpose of this study was to quantitatively characterize CSP lead tip to tissue responses for 4 commonly used leads. METHODS: CSP leads (from Medtronic, Biotronik, Boston Scientific, and Abbott) were examined for helix rotation efficiency in ex vivo ovine right ventricular septa. A custom jig was utilized for rotation measurements. Fifteen turns were executed, documenting tissue-interface changes every 90° using high-resolution photography. Response curves (input rotation vs helix rotation) were evaluated using piecewise linear regression, with a focus on output vs input response slopes and torque breakpoint events. RESULTS: We analyzed 3,840 quarter-turn CSP insertions with 4 different lead types. Helix rotations were consistently less than input: Abbott Tendril = 0.21:1, Medtronic 3830 = 0.21:1, Biotronik Solia = 0.47:1, and Boston Scientific Ingevity = 0.56:1. Torque breakpoint events were observed on average 7.22 times per insertion (95% CI: 6.08-8.35; P = NS) across all leads. In 57.8% of insertions (37 of 64), uncontrolled torque breakpoint events occurred, signaling unexpected excess helix rotations. CONCLUSIONS: Using a robust ex vivo model, we revealed a muted helix rotation response compared with input turns on the lead, and frequent torque change events during insertion. This is critical for CSP implanters, emphasizing the potential for unexpected torque breakpoint events, and suggesting the need for novel lead designs or deployment methods to enhance CSP efficiency and safety.


Assuntos
Sistema de Condução Cardíaco , Humanos , Animais , Ovinos , Torque , Sistema de Condução Cardíaco/fisiologia , Boston
5.
Heart Lung Circ ; 32(11): 1369-1377, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37914540

RESUMO

BACKGROUND: Recent clinical trials have demonstrated that sodium-glucose cotransporter 2 inhibitors (SGLT2i), which were previously only indicated in treatment of type 2 diabetes mellitus (T2DM), can markedly reduce heart failure hospitalisation (HFH), with less striking potential reductions in acute coronary syndromes and cardiac arrhythmias. To evaluate the impact of SGLT2i on cardiovascular outcomes in real-world practice, we performed a retrospective cohort analysis on South Australian (SA) data. METHODS: A total of 842 individuals with T2DM receiving SGLT2i were identified from SA public hospitals between 2011 and 2019. Episodes of care were temporally matched with those of 3,128 individuals with T2DM not receiving SGLT2i (control). Baseline characteristics were adjusted using inverse probability treatment weighting. The incidence of cardiovascular events at 12 and 24 months was evaluated using coded (International Classification of Diseases, Tenth Revision, Australian Modification [ICD-10-AM]) data. RESULTS: The primary outcome of HFH was lower with SGLT2i use at 12 months (adjusted hazard ratio [HRadj] 0.44; 95% confidence interval [CI] 0.29-0.68; p<0.001) and 24 months. There were also lower hospitalisations due to acute myocardial infarction (HRadj 0.42; 95% CI 0.21-0.85; p=0.015) and atrial or ventricular arrhythmias (HRadj 0.29; 95% CI 0.14-0.59; p=0.001), with no difference observed in hospitalisation due to ischaemic cerebrovascular events. There was no difference in all-cause mortality at 12 months but interestingly a higher rate at 24 months (HRadj 2.08; 95% CI 1.59-2.72; p<0.001). Despite this, similar reductions in cardiovascular outcomes were observed at 24 months. CONCLUSION: Use of SGLT2i in patients with T2DM in SA was associated with reductions in cardiovascular events even before their recent Pharmaceutical Benefits Scheme (PBS) listing for heart failure. Furthermore, this analysis supports that SGLT2i play a role not only in HFH reduction but also in reducing coronary and tachyarrhythmic events. This real-world evidence supports the use of SGLT2i as broadly protective cardiovascular drugs.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Humanos , Austrália do Sul/epidemiologia , Austrália , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Estudos Retrospectivos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/epidemiologia , Átrios do Coração , Glucose , Sódio
6.
Heart Lung Circ ; 31(4): 462-468, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34656439

RESUMO

INTRODUCTION: Experienced echocardiographers can quickly glean diagnostic information from limited echocardiographic views. The use of limited cardiac ultrasound, particularly as a screening tool, is increasing. During the COVID-19 pandemic, limited cardiac ultrasound has the major advantage of reducing exposure time between sonographer and patient. The sensitivity and negative predictive value of a "screening" echocardiogram with highly limited views is uncertain. AIM/METHOD: We examined the accuracy of limited echocardiography in 203 consecutive, de novo studies. We used six images: parasternal long axis, with colour Doppler over the mitral valve, and aortic valve, and apical four-chamber with colour Doppler over the mitral valve, and tricuspid valve. We compared the interpretation of 12 subjects with the final echocardiogram report, (gold standard). The subjects comprised four experienced echocardiography-specialised cardiologists, four experienced cardiologists with non-imaging subspecialty interests, and four senior cardiac sonographers. Studies were graded as: (1) normal or (2) needs full study (due to inadequate images or abnormality detected). Sensitivity, specificity, negative predictive value, positive predictive value and accuracy are reported. RESULTS: Forty-one per cent (41%) of studies were normal by the gold standard report. Overall, a screening echocardiogram had a sensitivity of 71.2%, specificity of 57.1% to detect an abnormal echocardiogram, negative predictive value 58.4%, positive predictive value of 70.2%, and accuracy of 65.4%. When inadequate images were excluded, overall accuracy was nearly identical at 64.6%. The overall accuracy between the three groups of interpreters was similar: 66.5% (95% CI 63.1-69.7) for echocardiography-specialised cardiologists, 65.3% (95% CI 61.9-68.5) for non-echocardiography specialised cardiologists, and 64.4% (95% CI 61.0-67.7) for sonographers. These groups are all highly experienced practitioners. There was no difference in sensitivity or specificity comparing echocardiography-specialised cardiologists with cardiologists of other subspecialty experience. Comparing cardiologists to sonographers, cardiologists had lower sensitivity (echocardiography specialists 67.6%, 95% CI 63.2-71.8, non-echocardiography specialists 62.0%, 95% CI 57.4-66.4) compared to sonographers (84.0% [95% CI 80.4-87.2, p<0.05]), but cardiologists had higher specificities (64.9% [95% CI 59.5-70.0] for the echocardiography specialists, and 69.9% [95% CI 64.7-74.8] for non echocardiography specialists), compared to 36.6% (95% CI 31.4-42.0, p<0.05) for the sonographer group. When looking at only the studies considered to be interpretable, cardiologists had higher positive predictive value (echocardiography specialists 73.7%, 95% CI 69.0-78.1, non echocardiography specialists 74.1%, 95% CI 68.8-79.9), as compared to sonographers (64.3%, 95% CI 59.8-68.5%). CONCLUSIONS: Limited cardiac ultrasound as a screening tool for a normal heart had a sensitivity of only 71%, when performed and interpreted by experienced personnel, raising questions regarding the safety of this practice. Caution is especially recommended in extrapolating its use to non-specialised settings.


Assuntos
COVID-19 , Pandemias , Ecocardiografia/métodos , Humanos , Programas de Rastreamento , Valva Mitral
8.
Europace ; 23(5): 665-673, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-33351904

RESUMO

Atrial fibrillation (AF) is an established independent risk factor for stroke. Current guidelines regard AF as binary; either present or absent, with the decision for anti-coagulation driven by clinical variables alone. However, there are increasing data to support a biological gradient of AF burden and stroke risk, both in clinical and non-clinical AF phenotypes. As such, this raises the concept of combining AF burden assessment with a clinical risk score to refine and individualize the assessment of stroke risk in AF-the CHA2DS2VASc-AFBurden score. We review the published data supporting a biological gradient to try and construct a putative schema of risk attributable to AF burden.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Humanos , Medição de Risco , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia
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