Effects of the Location of Myocardial Infarction on the Spectral Characteristics of Ventricular Fibrillation

Abstract

Background: The location of the myocardial infarction (MI) might modify the spectral characteristics of ventricular fibrillation (VF) in humans.Objective (PACE 2008; 31:660-665) myocardial infarction, ventricular fibrillation, spectral analysis, signal analysis, ICD, electrogram.

Characteristics of ventricular fibrillation in relation to cardiac aetiology and shock success: A waveform analysis study in ICD-patients

“…Characteristics of 4 s of induced VF before first shock delivery were analysed using Fourier analysis 14 . The spectral representation (normalised to unit area) was obtained using Welch's periodogram method (Hamming window (256 samples), 50% overlap and 1024 resolution samples) 15,16 . The following commonly determined frequency parameters were calculated: -The fundamental frequency: the lowest harmonic frequency, which corresponds to the VF cycle length 15 .…”

“…The spectral representation (normalised to unit area) was obtained using Welch's periodogram method (Hamming window (256 samples), 50% overlap and 1024 resolution samples) 15,16 . The following commonly determined frequency parameters were calculated: -The fundamental frequency: the lowest harmonic frequency, which corresponds to the VF cycle length 15 . -The median frequency: the frequency for which the integrated signal power was one half of the total integrated power from 1 to 25 Hz.…”

Ventricular fibrillation waveform characteristics of the surface ECG: Impact of the left ventricular diameter and mass

“…The mean amplitude and AMSA were log-transformed to approximate a normal distribution. All confounding variables as well as variables which have previously been associated with the outcome measure of interest were offered to the models [16][17][18].…”

“…Measures related to the VF amplitude Acute myocardial infarction [13][14][15] = ↓/= Previous myocardial infarction [13,[16][17][18]22] ↓/= ↓ Increased LV diameter [17] ↓ = Increased LV mass = ↑/= Low LV ejection fraction [33] ↓ Unk Beta blockers [28] ↓ Unk Class III anti-arrhythmic drugs [17] ↓ = Longer arrest duration [34,35] ↓ ↓ CPR [36,37] ↑ ↑ CPR: cardiopulmonary resuscitation, LV: left ventricular, unk: unknown, VF: ventricular fibrillation.…”

“…In contrast, studies in OHCA-patients yielded inconsistent results with regard to the impact of an acute MI [13][14][15]. Besides acute factors, there is robust evidence in both patients and animals that pre-existent cardiac disease affects VF characteristics as well [12,[16][17][18]. Previous studies primarily investigated the impact of infarction, while there is scarcity of data on the effect of other pre-existent disease-related changes of the myocardium on VF characteristics [16][17][18].…”