Comparison of Laplacian and Bipolar ECGs for R-wave Detection during Noise

Is Surface ECG a Useful Surrogate for Subcutaneous ECG?

“…Song et al reported that the correlation between surface and subcutaneous bipolar ECGs measured with an acutely implanted device at rest ranged between 0.81 and 0.99, 19 while Nabutovsky et al 20 reported an average correlation of surface and subcutaneous ECGs measured during a variety of resting and exercise maneuvers of 0.87. Additionally, the range of R‐wave amplitudes and SNRs compares well with those previously reported for both subcutaneous 10,25 and surface ECGs 10,26 recorded from a closely spaced bipolar ECG measured at approximately the same location on the chest. Our study is the first to assess the signal correlation separately during a variety of controlled positions and maneuvers over a relatively large number of patients with chronically implanted devices and to extend these results to a comparison of surface and subcutaneous ECG R‐wave amplitude, SNR, and R‐wave detection performance.…”

Feasibility of Real-Time Magnetic Resonance Imaging for Catheter Guidance in Electrophysiology Studies

“…Intracardiac electrogram signalto-noise ratio (SNR) was calculated as the signal (peak to trough atrial or ventricular electrogram) voltage to the (diastolic interval) root mean square noise ratio for each signal-signal interval and averaged over 30 beats for the window of interest. 15 The authors had full access to and take full responsibility for the integrity of the data. All authors have read and agree to the manuscript as written.…”