- Poster presentation
- Open Access
Real-ECG extraction and stroke volume from MR-Compatible 12-lead ECGs; testing during stress, in PVC and in AF patients
https://doi.org/10.1186/1532-429X-13-S1-P6
© Ho Tse et al; licensee BioMed Central Ltd. 2011
- Published: 2 February 2011
Keywords
- Stroke Volume
- Atrial Fibrillation Patient
- Processing Block
- Vary Heart Rate
- Subject Result
Background
Due to the Magneto-Hydro-Dynamic (MHD) effect, blood flow within the MRI’s magnetic field (B0) produces a large voltage during the S-T cardiac segment [1]. The peak MHD voltage (VMHD) can be comparable, in higher-field MRIs, to the R-wave amplitude of the real Electrocardiogram (ECGreal), so that VMHD reduces ECG-gating reliability and prevents ischemia-monitoring during cardiac imaging/interventions. We hypothesized that (1) separation of ECGreal and VMHD from 12-lead ECGs acquired within a 1.5T MRI could be achieved, using adaptive filtering, based on a set of ECG calibration measurements, and (2) a non-invasive beat-to-beat stroke-volume estimation could be achieved from time-integrated systolic VMHD.
Methods
ECGs measured at 3 positions; outside the field (i) and at isocenter with head-in (ii) and feet-in (iii).
Adaptive filtering diagram used for intermittent PVC patients, with beats separated and then processed independently at abnormal/normal beat filters.
Results
Results from a PVC patient (Ejection Fraction 20-25%, mitral regurgitation.
Results from AF patient (100-150 bpm)
Results from athlete subject during treadmill stress test (44-87 bpm)
Stroke-volume comparison (cardiac cycles n=20 per subject). Athlete (+24%), PVC (-54%) and AF (-23%), relative to average of volunteers.
Conclusions
The filtering extracts ECGreal from measured 12-lead ECG, preserving ECGreal for ischemia monitoring and MRI gating. Stroke volume can be non-invasively derived from the time-integrated systolic VMHD.
Authors’ Affiliations
References
- Gupta : IEEE Trans. BioMed. Eng. 2008Google Scholar
- Dukkipati. Circulation. 2008Google Scholar
Copyright
This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.