title: [Prevalence of late potentials in high frequency signal-averaged electrocardiography and arrhythmias in long-term ECG in healthy probands].
abstract: In a prospective study 79 symptom-free persons (41 females; 38 males) with an age range of 22-69 (mean 44) years were investigated by 48-h continuous ambulatory electrocardiography and by the signal-averaging ECG according to Simson's technique after having normal findings with echocardiography, standard ECG at rest and exercise stress test. Late potentials were defined according to Denes criteria (40 Hz highpass-filter); at least two out of the following three criteria had to be fulfilled for a correct positive finding: 1) QRS duration (QRSdur) greater than 120 ms; 2) root mean square of the last 40 ms (RMS 40) less than 20 microV; 3) mean duration of terminal low-amplitude signals (LAdur) greater than 39 ms. With long-term ECG 25% of the test subjects had no ventricular extrasystoles (VES), 28% had uniform VES, 33% multiform VES, 10% couplets, and 4% short runs of ventricular tachycardia during 48-hour recordings. Only 19% of them showed more than 48 VES/48 h. Individuals of advanced age demonstrated arrhythmias of higher Lown classes, as well as more frequent VES. By applying the signal-averaging technique 12.6% of the apparently healthy individuals showed late potentials, but none had LAdur greater than 45 ms. Individuals of higher age had not more late potentials than the younger ones. However, individuals with incomplete right bundle branch block pattern (n = 6) demonstrated with 50% significantly more often later potentials in comparison to 9.6% of those without this pattern (n = 73) (P less than 0.05). There was no correlation between late potentials and spontaneous arrhythmias, neither with regard to Lown classes, nor with regard to the frequency of VES. In conclusion, late potentials may occur in some individuals without apparent cardiovascular disease; they are unrelated to age as well as to spontaneous ventricular arrhythmias in normals.
authors.affiliation: Medizinische Klinik Friedrich-Ebert-Krankenhauses Neumünster.
authors.forename: M
authors.initials: M
authors.lastname: Buerschaper
authors.forename: B D
authors.initials: BD
authors.lastname: Gonska
authors.forename: K P
authors.initials: KP
authors.lastname: Bethge
mesh_terms: D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis* / Q000503:physiopathology; D005117:Cardiac Complexes, Premature / Q000175:diagnosis / Q000503:physiopathology; D004562:Electrocardiography / Q000295:instrumentation; D015716:Electrocardiography, Ambulatory / Q000295:instrumentation*; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*
vernacular_title: Prävalenz von Spätpotentialen im Hochverstärkungs-Elektrokardiogramm und von Rhythmusstörungen im Langzeit-EKG bei Gesunden.