B-PO05-161 CONTRIBUTION OF TERMINAL ACTIVATION DELAY AND SIGNAL-AVERAGED ECG TO ARVC DIAGNOSIS: EXPERIENCE FROM NORDIC ARVC REGISTRY
Ævar Örn ÚlfarssonKristina H. HaugaaHenning BundgaardAnneli SvenssonPia DahlbergAlex Hørby ChristensenTrine MadsenEivind W. Aabel Jonas CarlsonTanja Charlotte FrederiksenTanja Charlotte FrederiksenThor EdvarsenHenrik Kjærulf JensenJesper Hastrup SvendsenPyotr G. Platonov
1
Citation
0
Reference
10
Related Paper
Citation Trend
Keywords:
Signal-averaged electrocardiogram
The natural history of late potentials after acute myocardial infarction (AMI) has been studied in the first 2 years following myocardial infarction (MI). The purpose of the study was to assess the influence of some time delays since MI, including a time delay longer than 2 years on signal‐averaged ECG (SAECG). SAECG was recorded at 40‐Hz high pass filtering in 40 patients 10 days after acute MI (SAECG 1), then repeated 6–12 months later (mean 9 ± 3 months) (SAECG 2), and then, 2–4 years later (mean 3 ± 2 years) (SAECG 3). QRS duration, root mean square voltage of the last 40 ms of QRS (RMS 40), and low amplitude signal duration (LAS) were measured at the first (1), second (2), and third recording (3). Results: (***P < 0.001) The analysis of individual results showed a lengthening QRS duration at the third recording only in patients who had a decreased left ventricular ejection fraction (LVEF) at the third recording. In 12 patients with LVEF > 40%, QRS duration did not change at the first and third recording (104 ± 15 vs 101 ± 12 ms). In all 28 patients, but one with LVEF < 40%, QRS duration increased from 107 ± 12 to 128 ± 18 ms*. There was no correlation between QRS duration and LVEF at the second recording and no correlation between QRS duration increase at the third recording and the presence or not of late potentials at the first recording. QRS duration lengthening at the third recording was significantly correlated with a left ventricular (LV) dilatation occurrence at the two‐dimensional echocardiogram. All arrhythmic events, but two, occurred in patients who developed a QRS duration prolongation and were significantly correlated (P < 0.01) to a mean longer QRS duration (132 ± 20 ms) than in patients without arrhythmic events (113 ± 17 ms). In conclusion, the patients with a LV impairment, and who developed a LV dilatation several months after AMI, presented a delayed lengthening of QRS duration noted only at least 2 years after infarction. These patients are at risk of arrhythmic events.
Signal-averaged electrocardiogram
Cite
Citations (15)
Signal-averaged electrocardiogram
Signal averaging
Cite
Citations (89)
Interpretation of signal-averaged electrocardiograms (SAECG) in the young could be of value in detecting those at risk for episodic ventricular tachycardia, but suffers from a lack of data in normal young people. The purpose of this study is to determine normal values for QRS duration and the duration and amplitude of terminal potentials on the SAECG in young adults. Thirty-two normal medical students were examined. With high pass filtering at 25 Hz, normal total QRS duration (QRS) varied as a function of sex and body size whereas low amplitude signal duration (LAS) did not. Ninety-five percent confidence limits are: QRS (male) 85-117 msec, QRS (female) 76-102 msec, and LAS 6-35 msec. Root mean square voltage of the terminal QRS showed a broad scatter, however none was less than 20 microvolts. High pass filtering at 40 Hz did not change the QRS duration, but resulted in significantly longer LAS duration and diminished RMS voltage. Because of the longer QRS and shorter LAS previously reported in the presence of right bundle branch block, the normal values reported here should not be applied in the presence of intraventricular conduction delay following surgical repair of congenital heart disease. They will, however, provide a basis for interpretation of SAECG in young adults with normal QRS duration.
Signal-averaged electrocardiogram
Signal averaging
Intraventricular conduction
Cite
Citations (36)
SIGNAL (programming language)
Cite
Citations (19)
Ventricular Late Potentials (VLPs) are important indicators of sudden cardiac death (SCD) in people with a history of heart attack. Many algorithms for VLPs detection are based on quantifying increases in the QRS complex duration due to VLPs make QRS complexes larger. We took High Resolution ECGs from 50 individuals in resting position with no heart-attack antecedents and we simulated a VLPs database according to the American Heart association and the European Society of Cardiology. Two cases were evaluated: the QRS duration of complexes with VLPs simulated without QRS-alignment and QRS duration with VLPs using time and amplitude QRS-alignment prior application of Signal Averaging Electrocardiography (SAECG). Considering QRS duration as an indicative of VLPs presence, results show that using amplitude and time alignment it is possible to reach a sensitivity of 0.96 and a specificity of 0.3, as opposed to 0.72 and 0.40, respectively, using only SAECG.
Signal-averaged electrocardiogram
Cite
Citations (0)
Ventricular dyssynchrony
Dilated Cardiomyopathy
Signal-averaged electrocardiogram
Basal (medicine)
Cite
Citations (51)
Signal-averaged electrocardiogram
Cite
Citations (9)
The effects of type I antiarrhythmic drugs on the signal-averaged electrocardiogram (SAECG) were analyzed in 58 patients with inducible sustained monomorphic ventricular tachycardia. SAECGs were acquired before and after drug therapy. A total of 99 drug trials were analyzed (mean 1.7 per patient). Analysis of temporal domain parameters included the duration of the QRS complex (QRSD), the high frequency total duration of the filtered QRS complex (HFTD), the duration of the signal under 40 microV (D40), initial QRS (HFTD minus D40), and the root mean square amplitude (RMSA) of the terminal 40 msec of the QRS signal. Changes in temporal parameters failed to predict drug efficacy. There were, however, type-specific drug effects on the SAECG. With the exception of type IB drugs, all drugs increased the QRSD, HFTD, and D40. Type IC drugs caused more prolongation of the QRSD and HFTD than type IA, IB, and the combination of IA+IB drugs. Prolongation of the HFTD was related to prolongation of the late potential and the initial portion of the QRS complex. A preferential effect of these drugs on the late potential was not observed. Type IC drugs also caused more prolongation of ventricular tachycardia cycle length than type IA or IB drugs. However, the increase in ventricular tachycardia cycle length did not correlate with a change in the SAECG. In summary, type I antiarrhythmic drugs cause a global slowing of ventricular activation. Although analysis of the SAECG following drug therapy was not useful for predicting drug efficacy, drug induced changes in the SAECG may be helpful for categorizing antiarrhythmic agents.
Signal-averaged electrocardiogram
Prolongation
Cite
Citations (7)
Cite
Citations (31)
Patients with congenital heart disease were investigated after operation using the echocardiogram, signal-averaged ECG (SAECG) and Holter ECG. 32 patients, age 13.1 y (5-31 y) and 13 controls, 14.0 y (8-21 y), were compared. Together with Butterworth filtering a second high pass filter (FIR digital filter) was introduced to analyse high frequency components not only at the end of the QRS complex. FIR high pass filtering of the whole QRS showed a significant correlation between impaired left ventricular ejection fraction and more fractionated QRS in the SAECG (p<0.003). No correlation was found between dysrhythmias in the 24-hour Holter ECG and SAECG findings. High frequency intra-QRS signal components seem to be related to functional impairment in patients with congenital heart disease after operation.
Signal-averaged electrocardiogram
Cite
Citations (0)