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- Koning, Olivier H. J., et al.
(författare)
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Fluoroscopic Roentgen stereophotogrammetric analysis (FRSA) to study three-dimensional stent graft dynamics
- 2009
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Ingår i: Journal of Vascular Surgery. - : Elsevier BV. - 1097-6809 .- 0741-5214. ; 50:2, s. 407-412
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Tidskriftsartikel (refereegranskat)abstract
- We report the clinical feasibility of fluoroscopic Roentgen stereophotogrammetric analysis (FRSA), a validated method to quantify, real time three-dimensional (3D) dynamic motion of stent grafts and the first clinical results after abdominal and thoracic endovascular repair (EVAR). Stent graft motion was measured at 30 (stereo) frames per second, during the cardiac cycle and in the patient after abdominal EVAR, due to respiratory action. Translational motions of the center of mass, diameter change, and rotational and axial motion could be measured. Quantification of 3D motion was not available until now. FRSA can provide crucial information on the forces exerted oil stent grafts and will, therefore, provide essential information for improvements in stent graft design. (J Vasc Surg 2009;50:407-12.)
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| 4. |
- Vardas, Panos E., et al.
(författare)
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Orientações para pacing cardíaco e terapia deressincronização cardíaca
- 2008
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Ingår i: Revista portuguesa de cardiologia : orgão oficial da Sociedade Portuguesa de Cardiologia = Portuguese journal of cardiology : an official journal of the Portuguese Society of Cardiology. - 0870-2551. ; 27:5, s. 639-687
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Tidskriftsartikel (refereegranskat)
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| 7. |
- de Koning, Enrico, et al.
(författare)
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AI Algorithm to Predict Acute Coronary Syndrome in Prehospital Cardiac Care: Retrospective Cohort Study
- 2023
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Ingår i: JMIR Cardio. - : JMIR Publications. - 2561-1011. ; 7:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: Overcrowding of hospitals and emergency departments (EDs) is a growing problem. However, not all ED consultations are necessary. For example, 80% of patients in the ED with chest pain do not have an acute coronary syndrome (ACS). Artificial intelligence (AI) is useful in analyzing (medical) data, and might aid health care workers in prehospital clinical decision-making before patients are presented to the hospital.Objective: The aim of this study was to develop an AI model which would be able to predict ACS before patients visit the ED. The model retrospectively analyzed prehospital data acquired by emergency medical services' nurse paramedics.Methods: Patients presenting to the emergency medical services with symptoms suggestive of ACS between September 2018 and September 2020 were included. An AI model using a supervised text classification algorithm was developed to analyze data. Data were analyzed for all 7458 patients (mean 68, SD 15 years, 54% men). Specificity, sensitivity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for control and intervention groups. At first, a machine learning (ML) algorithm (or model) was chosen; afterward, the features needed were selected and then the model was tested and improved using iterative evaluation and in a further step through hyperparameter tuning. Finally, a method was selected to explain the final AI model.Results: The AI model had a specificity of 11% and a sensitivity of 99.5% whereas usual care had a specificity of 1% and a sensitivity of 99.5%. The PPV of the AI model was 15% and the NPV was 99%. The PPV of usual care was 13% and the NPV was 94%.Conclusions: The AI model was able to predict ACS based on retrospective data from the prehospital setting. It led to an increase in specificity (from 1% to 11%) and NPV (from 94% to 99%) when compared to usual care, with a similar sensitivity. Due to the retrospective nature of this study and the singular focus on ACS it should be seen as a proof-of-concept. Other (possibly life-threatening) diagnoses were not analyzed. Future prospective validation is necessary before implementation.
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| 8. |
- ter Haar, C. Cato, et al.
(författare)
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Difference vectors to describe dynamics of the ST segment and the ventricular gradient in acute ischemia
- 2013
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Ingår i: Journal of Electrocardiology. - : Elsevier BV. - 1532-8430 .- 0022-0736. ; 46:4, s. 302-311
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Tidskriftsartikel (refereegranskat)abstract
- Background: The ECG is important in the diagnosis and triage of the acute coronary syndrome (ACS), especially in the hyperacute phase, the "golden hours," during which myocardial salvage possibilities are largest. An important triaging decision to be taken is whether or not a patient requires primary PCI, for which, as mentioned in the guidelines, the presence of an ST elevation (STE) pattern in the ECG is a major criterion. However, preexisting non-zero ST amplitudes (diagnostic, but also non-diagnostic) can obscure or even preclude this diagnosis. Methods: In this study, we investigated the potential diagnostic possibilities of ischemia detection by means of changes in the ST vector, Delta ST, and changes in the VG (QRST integral) vector, Delta VG. We studied the vectorcardiograms (VCGs) synthesized of the ECGs of 84 patients who underwent elective PTCA. Mean +/- SD balloon occlusion times were 260 +/- 76 s. The ECG ischemia diagnosis (ST elevation, STE, or non-ST-elevation, NSTE), magnitudes and orientations of the ST and VG vectors, and the differences Delta ST and Delta VG with the baseline ECG were measured after 3 min of balloon occlusion. Results: Planar angles between the Delta ST and Delta VG vectors were 14.9 +/- 14.0 degrees. Linear regression of Delta VG on Delta ST yielded Delta VG = 324. Delta ST (r = 0.85; P < 0.0001, Delta ST in mV). We adopted Delta ST > 0.05 mV, and the corresponding Delta VG > 16.2 mV.ms as ischemia thresholds. The classical criteria characterized the ECGs of 46/84 (55%) patients after 3 min of occlusion as STE ECGs. Combined application of the Delta ST and Delta VG criteria identified 73/84 (87%) of the patients as ischemic. Conclusion: Differential diagnosis by Delta ST and Delta VG (requiring an earlier made non-ischemic baseline ECG) could dramatically improve ECG guided detection of patients who urgently require catheter intervention. (C) 2013 Elsevier Inc. All rights reserved.
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| 9. |
- Velders, Matthijs A., et al.
(författare)
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Prognosis of elderly patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention in 2001 to 2011 : a report from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR) registry
- 2014
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Ingår i: American Heart Journal. - : Elsevier. - 0002-8703 .- 1097-6744. ; 167:5, s. 666-673
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Elderly patients constitute a growing part of the population presenting with ST-elevation myocardial infarction (STEMI). The use of primary percutaneous coronary intervention (PCI) in this high-risk population remains poorly investigated.METHODS: Using the Swedish Coronary Angiography and Angioplasty Registry (SCAAR), we identified consecutive patients with STEMI 80 years or older undergoing primary PCI during a 10-year period. Temporal trends in care and 1-year prognosis were investigated, and long-term outcome was compared with a reference group of patients with STEMI aged 70 to 79 years. Relative survival was calculated by dividing the observed survival rate with the expected survival rate of the general population. Adjusted end points were calculated using Cox regression.RESULTS: In total, 4,876 elderly patients with STEMI were included. During the study period, average age and presence of comorbidity increased, as well as the use of antithrombotic therapy. Procedural success remained constant. One-year mortality was exclusively reduced between the most recent vs the earliest cohort, whereas the risk of reinfarction, heart failure, stroke, and bleeding remained similar. The risk of death was higher for elderly patients early after PCI, after which the prognosis was slightly better compared with the general population. Long-term risk of adverse events increased markedly with age.CONCLUSIONS: The prognosis of patients older than 80 years treated with primary PCI for STEMI was relatively unchanged during the 10-year inclusion period, despite changes in patient characteristics and treatment. Advanced age increased the risk of adverse events, but survivors of the early phase after PCI had a slightly improved prognosis compared with the general population.
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