Improved detection of acute myocardial infarction using a diagnostic algorithm based on calculated epicardial potentials

Epicardial potentials computed from the body surface potential map using inverse electrocardiography and an individualised torso model improve sensitivity for acute myocardial infarction diagnosis

“…Previous work from our centre has shown improvement in AMI detection with an epicardial algorithm using a standard torso in patients with a non-diagnostic 12L ECG. 7 Compared to other ECG techniques that were assessed, an epicardial algorithm correctly identified 53/83 patients with a non-diagnostic 12L ECG at presentation as AMI (sensitivity 64%, specificity 99%), findings that are comparable to those presented in this study (41/63 patients; sensitivity 65%, specificity 94%).…”

“…During the interpretation process, the electrodes are defined to represent anterior, lateral, inferior, high right anterior, right ventricular and posterior epicardial regions. 7 Harness application takes 3–4 minutes. BSPMs were recorded over 5–10 seconds at a sampling rate of 1 kHz and a bandwidth of 0.05–100 Hz and transferred into a digital format for core laboratory analysis.…”

“…where noise or movement artefacts disallowed recognition of QRST variables) were marked and substituted using linear grid interpolation. 7 Any BSPM with more than six leads requiring interpolation were disregarded and these patients excluded from analysis. Printouts were obtained from the processed BSPM of the 80-lead ECG and a colour-contour map displaying the amount of STE at the J-point (ST0 isopotential map) and confirmed by a cardiologist blinded to the 12L ECG result was produced.…”

“…Epicardial potentials (EPs) derived from body surface potentials (a process known as inverse ECG) further improve AMI diagnosis by removing the effect of the thoracic volume on electrical conduction. 7 However, to date, the method used to derive EPs assumes that all patients have torso geometries similar to an athletic, adult male. In an increasingly obese population, individualised inverse ECG has the potential to further improve AMI diagnosis, since an individualised torso geometry has shown potential in deriving more accurate EPs than those calculated using an undiscriminating male standard.…”

Improvement of the detection of myocardial ischemia thanks to information technologies

“…Other studies also reported about the interest to take into account additional, computer derived ECG information for improving the detection of acute myocardial ischemia or infarction, by analyzing either high frequency components of the QRS wave [18], or epicardial potentials calculated from 80-lead body surface maps [19]. These methods resulted in a substantial increase in sensitivity but still 10 to 13% lower than the one we obtained.…”