Analysis of the Prevalence of Ventricular Late Potentials in the Late Phase of Myocardial Infarction Based on the Site of Infarction

Abstract

Objective -The initial site of myocardial infarction (MI) may influence the prevalence of ventricular late potentials (VLP), high-frequency signals, due to the time course of ventricular activation. The prevalence of VLP in a period of more than 2 years after acute MI was assessed focusing on the initially injured wall . Methods - [1][2][3] . Due to the low velocity of conduction, these potentials exceed the duration of ventricular activation and are detected in the ST-segment. The use of statistical techniques, in which 2 to 3 hundred sequential QRS complexes detected on the body surface are independently coherent-averaged, allows amplification and identification of these signals because of the reduction in the intensity of the instrumentation noises 4-7 .The identification of ventricular late potentials in patients with a transmural myocardial infarction is of major interest 3,[8][9][10] . The myocardial remodeling process that follows transmural myocardial infarction is characterized by fibrosis, redistribution of fibers in the injured region, and residual metabolic alterations not only plays a major role in segmentary myocardial function but also provides a favorable environment for the development of reentry circuits 11 .Considering these markers, preliminary studies suggest that transmural myocardial infarctions involving the inferiorinferodorsal wall have a higher prevalence of ventricular late potentials than those involving the anterior-anteroseptal wall. These findings are based on differences related to the start of electrical activation in the affected regions 12,13 . However, studies relating the prevalence of ventricular late potentials after transmural myocardial infarction with the affected wall show some conflicting results. Some studies have focused attention on the occurrence of ventricular late potentials in the first 12 months after transmural myocardial infarction when the myocardial remodeling process is still underway 14 . Data on the prevalence of ventricular late potentials in a late phase (>2 years) of transmural myocardial infarction are very scarce. In this phase, the prevalence of ventricular late potentials reflects not only the natural

Electrocardiographic recordings of psychiatric patients attending Dawanau Psychiatric hospital, Kano-Nigera

“…Sudden cardiac arrest has been linked to late potentials in ECG of up to 31% of psychiatric (Poncet et al, 2015). Late ventricular potentials (LVPs) have been defined as low amplitude, high frequency waveforms that appear in the terminal part of the QRS complex of the electrocardiogram (Benchimol-Barbosa et al, 2002). In the same vein, some of these drugs have effect on QT interval, causing Torsade de pointes and sudden death in many patients receiving treatment.…”

Laboratory Markers of Ventricular Arrhythmia Risk in Renal Failure

“…LVPs are low amplitude, high frequency waveforms, appearing in the terminal part of the QRS complex [16]. LVPs are present, if, according to an international convention, at least 2 of the following 3 criteria are positive: SAECG-QRS duration >120 ms, low amplitude signal (LAS40; the duration of the terminal part of the QRS complex with an amplitude below 40  μ V) >38 ms, and root mean square signal amplitude of the last 40 ms of the signal (RMS40) <20  μ V [17].…”

Comparative analysis on wavelet-based detection of finite duration low-amplitude signals related to ventricular late potentials

“…No consensus has been established so far for any frequency band to extract reliable time-domain parameters. The choice of filter cutoff as reported by some of the researchers is presented in table 2 (Barbosa et al 2002), and as can be seen the choice will affect all resultant parameters where prevalence indicates the number of accurately detected cases.…”