EKG:n pitkäaikaisrekisteröinti

Vertaisarvioitu. Näin tutkin.EKG:n pitkäaikaisrekisteröinnillä tarkoitetaan menetelmiä, joiden avulla sydämen sähköistä toimintaa seurataan mukana kuljetettavan rekisteröintilaitteen avulla. Alkuperäisen, Sir Norman Holterin kehittämän, EKG:tä jatkuvasti rekisteröivän laitteiston rinnalle on sittemmin kehitetty menetelmiä, joissa talteen kerätään ainoastaan tietyt kriteerit täyttävät löydökset sekä löydökset tutkittavan potilaan oireiden ajalta. Tavallisimmat EKG:n pitkäaikaisrekisteröinnin aiheet ovat olleet rytmihäiriötuntemusten selvittely ja etiologialtaan epäselvä synkopee. Rekisteröintilaitteiden sekä muun kardiologisen diagnostiikan ja hoidon kehitys on merkittävästi laajentanut ja muovannut tutkimusaiheita

Effects of Epinephrine and Phenylephrine on QT Interval Dispersion in Congenital Long QT Syndrome 11This study was supported by a grant from the Finnish Cardiac Research Foundation, Helsinki.

AbstractObjectives. Measurement of QT interval dispersion during pharmacologic adrenergic stimulation was used to assess the effect of alpha- and beta-adrenergic stimulation on arrhythmic vulnerability in familial long QT syndrome (LQTS).Background. Nonhomogeneity in the ventricular action potential duration causes electrical instability leading to life-threatening ventricular arrhythmias and is markedly increased in LQTS. QT interval dispersion measured from the electrocardiogram (ECG) can be used as an index of nonhomogeneous ventricular repolarization.Methods. Sixteen symptomatic patients with LQTS and nine healthy control subjects were examined at baseline and during epinephrine (mainly beta-adrenergic agonist, 0.05 μg/kg body weight per min) and phenylephrine infusions (alpha-adrenergic agonist, mean 1.4 μg/kg per min). QT interval dispersion was determined from a 12-lead ECG as interlead range and coefficient of variation measured to the end (QTend) and apex (QTapex) of the T wave.Results. At baseline QTenddispersion was greater in patients with LQTS compared with control subjects (mean [±SD] 68 ± 34 vs. 36 ± 7 ms, p = 0.001). QTenddispersion was markedly increased in patients with LQTS by use of epinephrine (from 68 ± 34 to 90 ± 36 ms, p = 0.002), but remained unchanged in control subjects. Phenylephrine did not affect QT dispersion in either group (all p = NS). Atrial pacing to achieve comparable heart rates during baseline and epinephrine and phenylephrine infusions did not influence the magnitude of QT dispersion in either group. QTapexdispersion analysis gave congruent results.Conclusions. Epinephrine but not phenylephrine increased QT dispersion, suggesting that beta-adrenergic stimulation provokes arrhythmias in patients with LQTS by aggravating nonhomogeneity of ventricular repolarization, whereas alpha-adrenergic stimulation is less important for arrhythmic vulnerability. The results also suggest that rapid pacing may not reduce vulnerability to arrhythmias in congenital LQTS

Tunnistatko amiodaronin haittavaikutukset?

Amiodaroni on erittäin tehokas, mutta potentiaalisesti toksinen rytmihäiriölääke. Jokaisen potilaita hoitavan lääkärin tulee osata epäillä sen haittavaikutuksia. Niiden hoito ja amiodaronilääkityksen jatkaminen arvioidaan erikoissairaanhoidossa

A novel partial de novo duplication of JARID2 gene causing a neurodevelopmental phenotype

Publisher Copyright: © 2022 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals LLC.Background: Deletions covering the entire or partial JARID2 gene as well as pathogenic single nucleotide variants leading to haploinsufficiency of JARID2 have recently been shown to cause a clinically distinct neurodevelopmental syndrome. Here, we present a previously undescribed partial de novo duplication of the JARID2 gene in a patient displaying features similar to those of patients with JARID2 loss-of-function variants. Case report: The index patient presents with abnormalities in gross motor skills and speech development as well as neuropsychiatric disorders. The patient has markedly dark infraorbital circles and slightly prominent supraorbital ridges.Whole-genome sequencing and array comparative genomic hybridization revealed a novel disease-causing variant type, a partial tandem duplication of JARID2, covering the exons 1–7. Furthermore, RNA sequencing validated the increased expression of these exons. Expression alterations were also detected in target genes of the PRC2 complex, in which JARID2 acts as an essential member. Conclusion: Our data add to the variety of different pathogenic variants associated with JARID2 neurodevelopmental syndrome.Peer reviewe

Effects of beta-blockers on ventricular repolarization documented by 24-hour electrocardiography in long QT syndrome type 2

Peer reviewe

Katekoliamiiniherkkä monimuotoinen kammiotakykardia (CPVT) - harvinainen mutta vaarallinen sydänsairaus

Vertaisarvioitu.Katekoliamiiniherkkä monimuotoinen kammiotakykardia (CPVT) on harvinainen mutta vakava perinnöllinen rytmihäiriösairaus, johon liittyy hoitamattomana merkittävä äkkikuoleman riski. Sairauden tunnusomainen piirre on rasituksen aikana ilmaantuva monimuotoinen kammiolisälyöntisyys, vaikka potilaiden lepo-EKG on normaali eikä sydämessä todeta rakenteellisia poikkeavuuksia. Kliininen rasituskoe on keskeinen tutkimus CPVT:n diagnosoinnissa. Syy rytmihäiriöalttiudelle johtuu sydänlihassolujen kalsiumviestintään vaikuttavista mutaatioista, ja geenivirhe pystytään toteamaan noin kahdessa tapauksessa kolmesta. Lähisukulaisten tutkiminen on tärkeää, jotta kaikki sydäntapahtumille alttiit henkilöt saadaan ehkäisevien toimien sekä hoidon piiriin. CPVT-potilaiden tulee välttää raskasta urheilua ja tilanteita, joissa he voivat altistua voimakkaille yllättäville stressitekijöille. Potilaille aloitetaan beetasalpaajahoito, ja valikoiduissa tapauksissa käytetään flekainidia. Pienelle osalle potilaista on aiheen asentaa defibrilloiva rytmihäiriötahdistin.Peer reviewe

Waveform prototype-based feature learning for automatic detection of the early repolarization pattern in ECG signals

Objective: Our aim was to develop an automated detection method, for prescreening purposes, of early repolarization (ER) pattern with slur/notch configuration in electrocardiogram (ECG) signals using a waveform prototype-based feature vector for supervised classification. Approach: The feature vectors consist of fragments of the ECG signal where the ER pattern is located, instead of abstract descriptive variables of ECG waveforms. The tested classifiers included linear discriminant analysis, k-nearest neighbor algorithm, and support vector machine (SVM). Main results: SVM showed the best performance in Friedman tests in our test data including 5676 subjects representing 45408 leads. Accuracies of the different classifiers showed results well over 90%, indicating that the waveform prototype-based feature vector is an effective representation of the differences between ECG signals with and without the ER pattern. The accuracy of inferior ER was 92.74% and 92.21% for lateral ER. The sensitivity achieved was 91.80% and specificity was 92.73%. Significance: The algorithm presented here showed good performance results, indicating that it could be used as a prescreening tool of ER, and it provides an additional identification of critical cases based on the distances to the classifier decision boundary, which are close to the 0.1 mV threshold and are difficult to label.Peer reviewe

Waveform prototype-based feature learning for automatic detection of the early repolarization pattern in ECG signals

Objective: Our aim was to develop an automated detection method, for prescreening purposes, of early repolarization (ER) pattern with slur/notch configuration in electrocardiogram (ECG) signals using a waveform prototype-based feature vector for supervised classification. Approach: The feature vectors consist of fragments of the ECG signal where the ER pattern is located, instead of abstract descriptive variables of ECG waveforms. The tested classifiers included linear discriminant analysis, k-nearest neighbor algorithm, and support vector machine (SVM). Main results: SVM showed the best performance in Friedman tests in our test data including 5676 subjects representing 45408 leads. Accuracies of the different classifiers showed results well over 90%, indicating that the waveform prototype-based feature vector is an effective representation of the differences between ECG signals with and without the ER pattern. The accuracy of inferior ER was 92.74% and 92.21% for lateral ER. The sensitivity achieved was 91.80% and specificity was 92.73%. Significance: The algorithm presented here showed good performance results, indicating that it could be used as a prescreening tool of ER, and it provides an additional identification of critical cases based on the distances to the classifier decision boundary, which are close to the 0.1 mV threshold and are difficult to label.Peer reviewe

Prediction of sudden cardiac death with automated high-throughput analysis of heterogeneity in standard resting 12-lead electrocardiograms

BACKGROUND Heterogeneity of depolarization and repolarization underlies the development of lethal arrhythmias. OBJECTIVE We investigated whether quantification of spatial depolarization and repolarization heterogeneity identifies individuals at risk for sudden cardiac death (SCD). METHODS Spatial R-, J-, and T-wave heterogeneity (RWH, JWH, and TWH, respectively) was analyzed using automated second central moment analysis of standard digital 12-lead electrocardiograms in 5618 adults (2588, 46% men; mean +/- SEM age 50.9 +/- 0.2 years), who took part in the epidemiological Health 2000 Survey as representative of the entire Finnish adult population. RESULTS During the follow-up period of 7.7 +/- 0.2 years, a total of 72 SCDs occurred (1.3%), with an average yearly incidence rate of 0.17% per year. Increased RWH, JWH, and TWH in left precordial leads (V-4-V-6) were univariately associated with SCD (P = 102 mu V) was associated with a 1.7-fold adjusted relative risk for SCD (95% confidence interval [CI] 1.0-2.9; P = .048) and increased JWH (>= 123 mu V) with a 2.0-fold adjusted relative risk for SCD (95% CI 1.2-3.3; P = .006). When both TWH and JWH were above the threshold, the adjusted relative risk for SCD was 2.9-fold (95% CI 1.5-5.7; P = .002). When RWH (>= 470 mu V), JWH, and TWH were all above the threshold, the adjusted relative risk for SCD was 3.2-fold (95% CI 1.4-7.1; P = .009). CONCLUSION Second central moment analysis of standard resting 12-lead electrocardiographic morphology provides an ultrarapid means for the automated measurement of spatial RWH, JWH, and TWH, enabling analysis of high subject volumes and screening for SCD risk in the general population.Peer reviewe

Genealogy and clinical course of catecholaminergic polymorphic ventricular tachycardia caused by the ryanodine receptor type 2 P2328S mutation

Background Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a severe inherited arrhythmic disease associated with a risk of syncope and sudden cardiac death (SCD).Aims We aimed at identifying RYR2 P2328S founder mutation carriers and describing the clinical course associated with the mutation.Methods The study population was drawn from the Finnish Inherited Cardiac Disorder Research Registry, and from the present genealogical study. Kaplan-Meier graphs, log-rank test and Cox regression model were used to evaluate the clinical course.Results Genealogical study revealed a common ancestor couple living in the late 17(th) century. A total of 1837 living descendants were tested for RYR2 P2328S mutation unveiling 62 mutation carriers aged mean 3923 years old. No arrhythmic deaths were documented among genotyped subjects, but 11 SCDs were detected in non-genotyped family members since 1970. Three genotyped patients (5%) suffered an aborted cardiac arrest (ACA), and 15 (25%) had a syncope triggered by exercise or stress. Rate of cardiac events was higher among patients who in exercise stress test showed a maximum rate of premature ventricular contractions >30/min (68% vs 17%, p<0.01; hazard ratio = 7.1, p = 0.02), in comparison to patients without the respective finding. A cardioverter-defibrillator (ICD) was implanted to 13 (22%) patients, with an appropriate ICD shock in four (31%) subjects. All ICD shocks, one ACA, and one syncope occurred during -blocker medication.Conclusions Previously undiagnosed CPVT patients may be identified by well-conducted genealogical studies. The RYR2 P2328S mutation causes a potentially severe phenotype, but its expression is variable, thus calling for additional studies on modifying factors