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Case studies: urgent decisions in interventional radiology
Published in William H. Bush, Karl N. Krecke, Bernard F. King, Michael A. Bettmann, Radiology Life Support (Rad-LS), 2017
Discussion It is very common for ectopy to occur during pulmonary angiography as the right ventricle is traversed with the guidewire and catheter, due to the irritability of this chamber. This is particularly troublesome in certain patients, such as those who are recently post myocardial infarction (MI), have had recent cardiac surgery, have underlying arrhythmias or have a left bundle branch block. These arrhythmias generally consist of runs of premature ventricular contractions (PVCs). They almost always stop when the catheter and guidewire are removed from the right ventricle, or when the right ventricle is traversed and the catheter and guidewire lie in the pulmonary artery. Great care must be taken in all patients to ensure that the catheter is not positioned so as to allow the arrhythmias to persist. Some angiographers are careful to have a transcutaneous pacemaker or a transvenous pacing wire available in the case of patients with a history of arrhythmias, particularly those with left bundle branch block. No other specific precautions are necessary.
Detecting Premature Ventricular Contraction by Using Regulated Discriminant Analysis with Very Sparse Training Data
Published in Applied Artificial Intelligence, 2019
Analysis and interpretation of electrocardiograms (ECG) for monitoring cardiac abnormalities have been used and researched for many decades. Especially, computer-based ECG devices, which benefit from advanced signal-processing and machine learning, are wide spread today (Luz et al. 2016). These computer-based ECG devices collect and analyze the tiny electric impulses produced by the heart muscles. When the heart is healthy its produces an ECG signal with a characteristic shape that can be used by doctors to support their diagnosis. Any irregularity or arrhythmia in the ECG signal can indicate a serious heart condition. There are various types of arrhythmias that can be classified into different categories such as morphological arrhythmia and rhythmic arrhythmia. One arrhythmia that belongs to these groups is the premature ventricular contraction (PVC) or its synonym ventricular ectopic beat (VEB). This arrhythmia is very difficult to detect why it is subjected to intensive researched (Luz et al. 2016; Jambukia, Dabhi og Prajapati 2015; Chang et al. 2017).
Quantifying and Visualizing Uncertainty for Source Localisation in Electrocardiographic Imaging
Published in Computer Methods in Biomechanics and Biomedical Engineering: Imaging & Visualization, 2023
Dennis K. Njeru, Tushar M. Athawale, Jessie J. France, Chris R. Johnson
For example, in arrhythmias involving added abnormal beats, such as premature ventricular contraction (PVC), a region of cardiac tissue initiates pathological heartbeats, thereby increasing a patient’s risk of sudden death (Messineo 1989). The lack of high-resolution spatial information from the ECG in locating this region is problematic, because one method of therapy involves a clinician locating and destroying the region through an invasive interventional procedure called catheter ablation. A catheter ablation procedure may last several hours with a frequently high rate of recurrence of the arrhythmia (O’Donnell et al. 2003; Arya et al. 2010).