Stefan Nelwan

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OBJECTIVE To investigate whether the orientation of the electrical T-axis and the spatial QRS-T angle provide independent diagnostic and prognostic information in patients presenting with acute chest pain. METHODS Patients with symptoms suggestive of acute cardiac pathology, who were seen by a general practitioner and for whom a prehospital(More)
Medical applications are becoming increasingly available on portable devices such as smart phones, tablets and small notebooks in healthcare organizations. However, application development for diagnostic and monitoring purposes on these devices is still limited, because of regulatory requirements and significant development time and complexity for the(More)
In clinical practice, continuous recording of all leads of the 12-lead electrocardiogram (ECG) is often not possible. We wanted to assess how well absent, noisy, or defective leads can be reconstructed from different lead subsets and how well lead reconstruction performs over time. A data set of 234 24-hour ECG recordings was divided into an equally sized(More)
It may not always be possible to record all precordial leads of the standard 12-lead electrocardiogram (ECG). Especially in monitoring situations, a minimal lead set from which the 12-lead ECG can be reconstructed, would be valuable. This article assesses how well missing precordial leads could be synthesized from the remaining leads of the 12-lead ECG. A(More)
In this study, we assess the effects of electrode placement error on the EASI-derived 12-lead electrocardiogram (ECG). The study data set consisted of 744 body surface potential map (BSPM) recordings. The BSPMs, each of which was made up of 117 leads, were recorded from a mixture of healthy, myocardial infarction, and left ventricular hypertrophy subjects.(More)
OBJECTIVE To investigate the association between (cardiac) mortality and spatial QRS-T angle in patients undergoing dobutamine - atropine stress echocardiography (DSE) for evaluation of known or suspected coronary disease. METHODS Between 1990 and 2003, 2347 patients underwent DSE for evaluation of coronary disease at the Erasmus Medical Center.(More)
AIM The aim of the study was to simultaneously test the EASI lead system and two other derived ECG methods against the standard 12-lead ECG during percutaneous coronary intervention (PCI). METHODS During 44 percutaneous coronary interventions, a simultaneously recorded 12-lead and EASI ECG were marked at the start of the PCI (baseline) and at known(More)
AIMS To investigate whether, in patients in whom drug-drug interaction (DDI) alerts on QTc prolongation were overridden, the physician had requested an electrocardiogram (ECG), and if these ECGs showed clinically relevant QTc prolongation. METHODS For all patients with overridden DDI alerts on QTc prolongation during 6 months, data on risk factors for QT(More)
In this study we investigate the influence of ischemic events on the estimation accuracy of a reduced lead system based on leads I, II, V2 and V5. The estimation accuracy of this lead system has been assessed for generalized and patient specific lead derivation. Assessments have been performed on a piecewise homogenous torso model that has been used to(More)