PubMed · 14498019
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
L SCHAMROTH. 1961. Concealed retrograde conduction.. https://doi.org/10.1016/0002-9149(61)90372-1
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
The mechanisms underlying normal and abnormal cardiac rhythms are complex and incompletely understood. Through the study of uncommon inheritable arrhythmia syndromes, including the long QT and Brugada syndromes, new insights are emerging. At the cellular and tissue levels, we now recognize that ion channel current is the sum of biophysical (gating, permeation), biochemical (phosphorylation, etc), and biogenic (biosynthesis, processing, trafficking, and degradation) properties. This review focuses on how heart cells process ion channel proteins and how this protein trafficking may be altered in some cardiac arrhythmia diseases. In this review, we honor Dr Harry A. Fozzard, a modern pioneer in cardiac arrhythmias, cell biology, and molecular electrophysiology. As a scientist and physician, his writings and mentorship have served to foster a generation of investigators who continue to bring this complex field toward greater scientific understanding and impact on humankind.
Explore the source record for details and available documents.
OBJECTIVES: The study was done to determine whether patients with pacemakers could safely undergo magnetic resonance imaging (MRI) at 1.5-Tesla (T). BACKGROUND: Because of theoretical risks, it is an absolute contraindication for a patient with a pacemaker to undergo MRI. However, there are times when an MRI is needed to provide valuable clinical information. METHODS: Fifty-four patients underwent a total of 62 MRI examinations at 1.5-T. The type of MRI examination was not limited and included cardiac, vascular, and general MRI studies using various whole-body averaged specific absorption rate (SAR) of radiofrequency power. Restrictions were not placed on the type of pacemaker present in the patient. All pacemakers were interrogated immediately before and after MRI scanning, and patients were continuously monitored. Before and after MRI, interrogation was done, and pacing and sensing thresholds, as well as lead impedances, were all measured. RESULTS: A total of 107 leads and 61 pulse generators were evaluated. No adverse events occurred. Forty (37%) of the leads underwent changes, whereas 10 (9.4%) leads underwent a significant change. Only 2 of the 107 (1.9%) leads required a change in programmed output. Threshold changes were unrelated to cardiac chamber, anatomical location, peak SAR, and time from lead implant to the MRI examination. Electrocardiographic changes and patient symptoms were minor and did not require cessation of MRI. CONCLUSIONS: Safety was demonstrated in this series of patients with pacemakers at 1.5-T.