Acute myocardial ischemia monitoring before and during angioplasty by a novel vectorcardiographic parameter set

Myocardial Ischemia Events Detection based on Support Vector Machines using QRS and ST Features

“…R-wave amplitude (ampR) for each lead, as ST60, was measured using the PR segment as the isoelectric level. QRSVD was computed from difference between the PCI and control QRS complexes areas in the VCG [3]. The QRS was band-pass filtering at the band of 150 to 250 Hz, using a Butterworth filter in a forwardbackward fashion; then, HFQRS indices were obtained from the RMS value of the filtered QRS [4].…”

“…However, other indices associated with the ventricular depolarization have also been considered to improve the diagnosis of ischemia. These QRS-derived features include the R-wave amplitude change [2], QRS area, QRS-vector difference [3] and high-frequency QRS (HFQRS) [4], computed on 12-lead ECG, the vectorcardiogram (VCG) or signal-averaged ECG (SAECG). Most of them have been individually studied, thus it is not clear what the relationship among them are.…”

Identification of Patients with Myocardial Infarction

“…Also, six from the orthogonal ECG leads (X, Y, Z), two evaluated on the QRS complex waves and four on the ST-T segment. In the same way as in previous works, we have analyzed beat-tobeat morphological changes of the VCG and ECG [5,6]. We defined Figure 2a).…”

“…Computed around the QRS-loop projected over the Optimum Plane. It measures the loop total length and can detect loop contour changes [5].…”

“…We concluded that QRS loop parameters combined with ST VM improved the sensitivity and specificity values with respect to those obtained using only the ST VM index. Furthermore, in [5], we extended the use of a similar set of QRS loop parameters to myocardial ischemia monitoring. It was demonstrated that these parameters, combined with the classic indexes, increase sensitivity and specificity for acute ischemia monitoring.…”