Repolarization Pattern Research Articles

P478Early repolarization pattern in patients with structural heart disease: can it really predict sudden cardiac death?

P478Early repolarization pattern in patients with structural heart disease: can it really predict sudden cardiac death?

P1040The Impact of testosterone levels on early repolarization patterns observed in healthy Turkish males

P1040The Impact of testosterone levels on early repolarization patterns observed in healthy Turkish males

Progression of early repolarization patterns at a four year follow-up in a female flight crew population: Implications for aviation medicine.

To assess the prevalence, the appearance, and the distribution, as well as the fluctuation over time of early repolarization patterns after four years in a female population derived from the French aviation sector. This was a retrospective longitudinal study from 1998 to 2010 of a population of female employees who received a full clinical examination and an electrocardiogram (ECG) upon their recruitment and after a period of four years. A total of 306 women were included (average of 25.87±3.3years of age). The prevalence of early repolarization was 9.2%. The most common appearance was J-point slurring for 64.3% (i.e. 20/28 subjects) that occurred in the inferior leads for 28.6% (i.e. 8/28 subjects). After four years, the prevalence was 7.5%, with a regression of this aspect in five of the subjects. There were no changes in the ECG in terms of the distribution and the appearance among the 23 subjects for whom the aspect persisted. Over the course of this four year period all of the subjects remained asymptomatic. Early repolarization in this largely physically inactive female population was common, and it fluctuated over time. At present, no particular restrictions can be placed on asymptomatic flight crew who exhibit this feature in the absence of a prior medical history for heart disease.

Prevalence of early repolarisation pattern in children

BackgroundPrevalence of early repolarisation ECG pattern (ER) has been repetitively determined in adults, but has not been reported in large unselected children populations so far. MethodsECG from 1000 successive healthy children from birth to 17years old were prospectively recorded and analyzed. ER was defined by ≥0.1mV J point elevation in at least two contiguous inferior or lateral ECG leads. Correlations with age, gender, ethnic origin, physical activity, Sokolow index and heart rate were performed. ResultsPrevalence of ER pattern was 23,6% (95% CI 21–26.2%) and increased after 8years of age. ER was independently correlated to a non Caucasian origin and a higher Sokolow index, but not to gender or level of physical activity. ER was independently correlated to an older age in children with heart rate <100bpm, and to a slower heart rate in children ≥8yo. ConclusionER is present in a quarter of children of various age and is related to ethnic origin, an older age, a slower heart rate and a higher Sokolow index.

Local transmural action potential gradients are absent in the isolated, intact dog heart but present in the corresponding coronary-perfused wedge.

The left ventricular (LV) coronary‐perfused canine wedge preparation is a model commonly used for studying cardiac repolarization. In wedge studies, transmembrane potentials typically are recorded; whereas, extracellular electrical recordings are commonly used in intact hearts. We compared electrically measured activation recovery interval (ARI) patterns in the intact heart with those recorded at the same location in the LV wedge preparation. We also compared electrically recorded and optically obtained ARIs in the LV wedge preparation. Five Langendorff‐perfused canine hearts were paced from the right atrium. Local activation and repolarization times were measured with eight transmural needle electrodes. Subsequently, left ventricular coronary‐perfused wedge preparations were prepared from these hearts while the electrodes remained in place. Three electrodes remained at identical positions as in the intact heart. Both electrograms and optical action potentials were recorded (pacing cycle length 400–4000 msec) and activation and repolarization patterns were analyzed. ARIs found in the subepicardium were shorter than in the subendocardium in the LV wedge preparation but not in the intact heart. The transmural ARI gradient recorded at the cut surface of the wedge was not different from that recorded internally. ARIs recorded internally and at the cut surface in the LV wedge preparation, both correlated with optically recorded action potentials. ARI and RT gradients in the LV wedge preparation differed from those in the intact canine heart, implying that those observations in human LV wedge preparations also should be extrapolated to the intact human heart with caution.

Prevalence of early repolarization pattern in patients with lone atrial fibrillation

BackgroundThe objective of this study was to test the association of early repolarization pattern (ER) with lone atrial fibrillation (AF). MethodsElectrocardiograms (ECGs) were analyzed in blinded fashion in a case–control study of 182 patients with lone AF and 182 controls without AF. ResultsPatients with lone AF and controls had similar frequencies of ER pattern (15% vs. 19%, p=0.40). In patients <50years of age, there was also no difference in the percentage of patients with ER in the AF and control groups (17% vs. 19%, p=0.60). ER pattern was more common in patients with ECG voltage criteria of left ventricular hypertrophy (LVH), with ER present in 57% of patients with elevated Sokolow-Lyon voltage compared to 14% of those without (p<0.0001). ConclusionsNo association could be identified between the ER pattern and lone AF in young and middle-aged patients. In this age group, ER is substantially more common in patients with elevated Sokolow-Lyon voltage criteria.

Novel trigenic CACNA1C/DES/MYPN mutations in a family of hypertrophic cardiomyopathy with early repolarization and short QT syndrome

BackgroundHypertrophic cardiomyopathy (HCM) patients with early repolarization (ER) pattern are at higher risk of ventricular arrhythmia, yet the genetic background of this situation has not been well investigated. Here we report novel trigenic mutations detected in a Chinese family of obstructive HCM with ER and short QT syndrome (SQTS).MethodsProband and family members underwent detailed medical assessments. DNAs were extracted from peripheral blood leukocytes for genetic screening with next generation method. The functional characterization of the mutation was conducted in TSA201 cells with patch-clamp experiment.ResultsThe proband was a 52-year-old male who had a ER pattern ECG in inferioral-lateral leads with atrioventricular block and QTc of 356 ms. He also suffered from severe left ventricular hypertrophy and dysfunction. Targeted sequencing revealed trigenic mutations: c.700G>A/p.E234K in DES, c.2966G>A/p.R989H in MYPN, and c.5918G>C/p.R1973P in CACNA1C. All mutations were also detected in his daughter with ER and mild myocardium hypertrophy. The CACNA1C-R1973P mutation caused significant reduction (68.4%) of ICa compared to CACNA1C-WT (n = 14 and 14, P < 0.05). The computer modeling showed that all 3 mutations were highly disease-causing. The proband received the CRT-D (cardiac resynchronizing therapy) implantation, which lowered the left ventricular outflow tract gradient (LVOTG, 124 mmHg pre vs. 27 mmHg post) and restored the LV function (LVEF 40% pre vs. 63% post).ConclusionsThe study reveals a novel CACNA1C mutation underlying the unique ER pattern ECGs with SQTS. It also shows the rare trigenic mutations are the pathogenic substrates for the complicated clinical manifestation in HCM patients.

Early Repolarization Is Not Always Benign

Early repolarization (ER) pattern is marked with J-point elevation, slurring or notching the terminal portion of the QRS and ST segment elevation has been considered benign over the last few decades. However, some reports now suggest a link between early repolarization and increased risk of death due to arrhythmias and idiopathic ventricular fibrillation (VF), known as ER syndrome. Implantable cardioverter-defibrillators implantation and drug isoproterenol are the suggested therapy in patients with ER syndrome. In contrast, patients without symptoms of the syndrome ER are common and have a better prognosis. Risk stratification in asymptomatic patients in the ER remains a gray area. There are still many unanswered questions, so studies exploring the underlying mechanisms of ER continues to be developed.

Early repolarization is associated with a significantly increased risk of ventricular arrhythmias and sudden cardiac death in patients with structural heart diseases

Early repolarization pattern (ERP) has been proved to increase risk of arrhythmia death in the general population, but its prognostic significance in patients with structural heart disease (SHD) is controversial. The purpose of this study was to conduct a meta-analysis of studies assessing the association between ERP and risk of ventricular arrhythmias (VTAs) and sudden cardiac death (SCD) in patients with SHD. We performed a literature search using MEDLINE (January 1, 1966, to September 25, 2016) and EMBASE (January 1, 1980, to September 25, 2016) with no restrictions. Studies that reported odds ratio (OR) estimates with 95% confidence intervals (CIs) for the associations of interest were included. The search yielded 19 observational studies, involving 7268 patients that reported 1127 cases of VTAs or SCD. In the selected studies, the point estimates of the ORs were consistently greater than 1. Compared with those without ERP, patients with ERP experienced a significantly increased risk of developing VTAs or SCD (OR 4.76; 95% CI 3.62-6.26), ventricular fibrillation (OR7.14; 95% CI 4.31-11.82), and SCD (OR 4.07; 95% CI 1.58-10.51). The results were consistent and statistically significant in all subgroups. ERP with J-point elevation in inferior leads, notching configuration, and horizontal or descending ST segment connote higher risk. ERP is associated with a significant increased risk of VTAs or SCD in patients with SHD. Future research should attempt to understand the exact mechanisms for the arrhythmia risk and to introduce ERP in the risk stratification in this patient group.

Selective His-Bundle Pacing May Preserve Intrinsic Repolarization as Well as Depolarization

A 79-year-old man with chronic atrial fibrillation underwent single-chamber His-bundle pacemaker implantation. The post-implant electrocardiogram (ECG) demonstrated selective His-bundle capture, with a narrow paced QRS and repolarization pattern similar to that of the baseline ECG. Furthermore, repolarization changes prototypic of ventricular pacing did not occur with selective His-bundle capture. While His-bundle pacing, with or without selective His-bundle capture, can preserve physiologic patterns of depolarization, only His-bundle selective pacing can preserve intrinsic ST- and T-wave patterns. Thus, the maintenance of physiologic repolarization may have various advantages, including accurate interpretation of ECG changes that are not generally interpretable in the setting of ventricular pacing.

Early Repolarization in Normal Adolescents is Common.

In adults with structurally normal hearts, the early repolarization pattern (ERP) on electrocardiogram (ECG) may be associated with an increased risk of sudden cardiac death. The prevalence and significance of the ERP in children is unknown. This study examines the prevalence of the ERP, the population in which it is found, and whether there exists any correlation with increased LV mass or family history of significant cardiac events. This was a secondary review of data obtained from healthy adolescents undergoing a limited ECG and transthoracic echocardiogram (TTE) as part of a cardiac screening study. Subjects were excluded if ECG revealed known arrhythmic syndromes or TTE revealed structural abnormalities. ERP was defined as (1) notching or slurring of the terminal QRS; (2) elevation of the QRS-ST junction ≥1mV; and (3) upwardly concave positive T-wave. Left ventricular (LV) mass was defined as mass/height2.7. Patient demographics, LV mass, family history of sudden death, arrhythmia, and/or ICD/pacemaker placement were compared for subjects with and without ERP on ECG. Data from 575 subjects (median age 15, range 13-18; 36% female; 93% Caucasian) were reviewed. The incidence of ERP was 40% (n = 228) and was seen in the inferior, lateral, or combination of these leads in 42, 10, and 48% of subjects with ERP, respectively. There was no difference in gender (p = 0.7), race (p = 0.7), age (p = 0.3), history of syncope (p = 0.2), LV mass (p = 0.8), family history of (a) sudden death (p = 0.5), (b) arrhythmia (p = 0.2), or (c) ICD/pacemaker requirement (p = 0.8) in subjects with ERP versus those without. However, a greater percentage of patients with ERP were noted to play football, when compared to those without ERP (34 vs. 13%, p < 0.001). ERP is common in healthy adolescents, and does not correlate with concerning personal/family history or elevated LV mass. Longitudinal studies are required to determine whether ERP in childhood confers an increased mortality risk.

The Electrophysiological Substrate of Early Repolarization Syndrome

The early repolarization (ER) pattern is a common ECG finding. Recent studies established a definitive clinical association between ER and fatal ventricular arrhythmias. However, the arrhythmogenic substrate of ER in the intact human heart has not been characterized. To map the epicardial electrophysiological (EP) substrate in ER syndrome patients using noninvasive Electrocardiographic Imaging (ECGI), and to characterize substrate properties that support arrhythmogenicity. Twenty-nine ER syndrome patients were enrolled, 17 of which had a malignant syndrome. Characteristics of the abnormal EP substrate were analyzed using data recorded during sinus rhythm. The EP mapping data were analyzed for electrogram morphology, conduction and repolarization. Seven normal subjects provided control data. The abnormal EP substrate in ER syndrome patients has the following properties: (1) Abnormal epicardial electrograms characterized by presence of J-waves in localized regions; (2) Absence of conduction abnormalities, including delayed activation, conduction block, or fractionated electrograms; (3) Marked abbreviation of ventricular repolarization in areas with J-waves. The action potential duration (APD) was significantly shorter than normal (196±19 vs. 235±21 ms, p<0.05). Shortening of APD occurred heterogeneously, leading to steep repolarization gradients compared to normal control (45±17 vs.7±5 ms/cm, p<0.05). Premature ventricular contractions (PVCs) were recorded in 2 patients. The PVC sites of origin were closely related to the abnormal EP substrate with J-waves and steep repolarization gradients. Early Repolarization is associated with steep repolarization gradients caused by localized shortening of APD. Results suggest association of PVC initiation sites with areas of repolarization abnormalities. Conduction abnormalities were not observed.

Long-Term Follow-Up of Probands With Brugada Syndrome

This study analyzes the natural history of a large cohort of probands with Brugada syndrome (BrS) to assess the predictive value of different clinical and electrocardiographic parameters for the development of ventricular fibrillation (VF) or sudden cardiac death (SCD) during a long-term follow-up. Baseline characteristics of 289 consecutive probands (203 men; mean age 45 ± 16years) with a Brugada type 1 electrocardiogram were analyzed. After a mean follow-up of 10.1 ± 4.6years, 29 malignant arrhythmias occurred. On multivariate analysis, a history of VF and syncopal episodes, fragmented QRS (f-QRS), spontaneous type 1 electrocardiogram, and early repolarization pattern were significantly associated with later occurrence of VF/SCD. In patients with drug-induced BrS, the accentuation or de novo appearance of f-QRS in other leads was always associated with VF/SCD. Cerebrovascular events occurred in 8 patients with atrial fibrillation (15.1%), most of them (75%) presenting as the first clinical manifestation. The time-to-diagnosis was found to be significantly shorter in those patients who directly came to our center than in those who referred to our center for a second opinion. In conclusion, systematic use of the pharmacologic challenge in patients with unexplained cardiovascular symptoms and/or atrial fibrillation might significantly improve the identification of BrS with a shortening of the time-to-diagnosis. The CHA2DS2VASc score might be inappropriate for predicting transient ischemic attack or stroke in BrS. This study confirms the independent predictive value of previous VF and syncopal episodes, f-QRS, type 1 electrocardiogram, and early repolarization pattern. In BrS a sufficiently long follow-up is necessary before conclusions on prognosis are apparent.

Local Left Ventricular Epicardial J Waves and Late Potentials in Brugada Syndrome Patients with Inferolateral Early Repolarization Pattern

Background: Brugada syndrome (BrS) is characterized by J-point or ST-segment elevation on electrocardiograms (ECGs) and increased risk of ventricular fibrillation (VF). In BrS, epicardial depolarization abnormality with delayed potential on the right ventricular outflow tract is reportedly the predominant mechanism underlying VF. Yet VF occurrence is also associated with early repolarization (ER) pattern in the inferolateral ECG leads, which may represent the inferior and/or left lateral ventricular myocardium. The aim of this study was to examine epicardial electrograms recorded directly at the left ventricle (LV) in BrS patients after VF episodes.Methods: In 12 BrS patients who had experienced VF episodes and 17 control subjects, a multipolar catheter was introduced into the left lateral coronary vein for unipolar and bipolar electrogram recordings at the LV epicardium. Both inferior and lateral ER patterns on ECG were observed in three BrS patients and six control subjects.Results: In the epicardium, prominent J waves were detected using unipolar recording, and potentials after the QRS complex were detected using bipolar recording in three of the 12 BrS patients. These three patients also showed both inferior and lateral ER patterns on ECG. Neither prominent J waves nor potentials after the QRS complex were recorded at the endocardium of the LV in any of these three patients; nor were they seen at the epicardium in any of the control subjects. These features were accentuated on pilsicainide administration (n = 2) but diminished on constant atrial pacing (n = 3) and isoproterenol administration (n = 1). The J waves observed through unipolar recording coincided with the potentials after QRS complex observed through bipolar recording and with the inferolateral ER patterns on ECG.Conclusions: We recorded prominent J waves in unipolar electrogram and potentials after QRS complex in bipolar electrogram at the LV epicardium in BrS patients with global ER pattern. The prominent J waves coincided with the potentials after QRS complex and the inferolateral ER pattern on ECG. The characteristics of the inferolateral ER pattern on ECG in these patients primarily represent depolarization feature.

A meta-analysis on the prognostic significance of inferolateral early repolarization pattern in Brugada syndrome.

The early repolarization (ER) pattern has been linked to an increased risk for arrhythmic death in various clinical settings. There are limited and conflicting data regarding the prognostic significance of ER pattern in Brugada syndrome (BS). The aim of this meta-analysis was to provide a detailed analysis of the currently available studies regarding the arrhythmic risk in patients with BS and ER pattern. Current databases were searched until May 2015. A random-effect meta-analysis of the effect of ER pattern on the incidence of arrhythmic events in patients with BS was performed. Five studies were included comprising a total of 1375 patients with BS. An ER pattern was reported in 177 patients (12.8%). During follow-up (44.9-93 months), 143 patients (10.4%) suffered an arrhythmic event. Overall, BS patients with ER pattern displayed an increased risk of arrhythmic events compared to patients without ER (OR 3.29, 95% CI: 2.06 to 5.26, P < 0.00001; Heterogeneity: P = 0.11, I2 = 48%). Three studies provided data regarding ER pattern location. Inferior, lateral, or inferolateral ER pattern location was observed in 20.3%, 32.2%, and 48%, respectively. An inferolateral ER location conferred the higher arrhythmic risk (OR 4.87, 95% CI: 2.64 to 9.01, P< 0.00001; Heterogeneity: P = 0.85, I2 = 0%). This meta-analysis suggests that the ER pattern is associated with a high risk of arrhythmic events in patients with BS. In particular, BS patients with inferolateral ER (global ER pattern) displayed the highest arrhythmic risk.

The relationship between electrocardiographic fish-hook sign and early diastolic left ventricular velocity in athletes

Objectives The aim of the present study was to find a relationship between ECG fish-hook sign and echocardiographic variables in football athletes. Background Early repolarization is a common finding among athletes. The notched or irregular J point is known as the fish-hook sign, and it is a pattern of early repolarization. Patients and methods The present cross-sectional study was conducted using 61, male football players who were recruited during precompetition medical assessments in June 2016. The study was carried out at the medical clinics of two sports clubs in the Kingdom of Saudi Arabia. Standard 12-lead resting ECG and two-dimensional echocardiography were performed for all participants. Results The mean age was 25.7 ± 4.47, the mean body surface area was 1.86 ± 0.11 cm2, the mean corrected QT interval was 408.7 ± 22.12 ms, the main left ventricular (LV) mass index was 104.9 ± 18.5 g/m2, and the main LV ejection fraction was 59.9 ± 4.53%. The fish-hook sign was present in 32 (52.4%) athletes. The presence of a fish-hook sign was not statistically different with respect to age, body surface area, QRS duration, corrected QT interval, and LV hypertrophy. Athletes with a fish-hook sign had higher early diastolic mitral annulus velocity (E') and lower E/E' compared with athletes who had no fish-hook sign (P Conclusion Athletes with a fish-hook sign had higher peak early diastolic mitral annular (E') velocity and lower E/E' compared with athletes who had no fish-hook sign.

120 - Early repolarization pattern is more frequent but not associated with greater risk of arrhythmic episodes in patients with long-QT syndrome

120 - Early repolarization pattern is more frequent but not associated with greater risk of arrhythmic episodes in patients with long-QT syndrome

Role and Potential Mechanisms of Early Repolarization Pattern in Patients with Vasospastic Angina

Role and Potential Mechanisms of Early Repolarization Pattern in Patients with Vasospastic Angina

Long-term prognosis associated with early repolarisation pattern in Chinese population with atherosclerotic risk factors

BackgroundRecent evidence has linked early repolarisation pattern (ERP) to sudden cardiac death (SCD) in patients without structural heart disease. However, no studies have clarified the prognostic value of ERP in...

Early repolarization pattern in the general population: Prevalence and associated factors

ObjectivesTo evaluate the prevalence of early repolarization pattern (ERP) in the general rural Chinese population and identify the contributing risk factors. MethodsA cross-sectional study of 11,956 permanent residents of Liaoning Province ≥35y of age was conducted between January and August 2013 (response rate 85.3%). ERP was diagnosed if there was J-point elevation of ≥0.1mV in ≥2 leads in the inferior (II, III, aVF) or lateral (I, aVL, V4–6) territory, or both. Risk factors for ERP were evaluated with a stepwise logistic regression analysis. ResultsThe overall prevalence of ERP was 1.3%, and it was higher in men than women (2.6 vs. 0.2%, P<0.001), decreasing with increasing age. Percent of ERP positive in lateral leads, inferior, and both was 73.0%, 15.3%, and 11.7%, respectively. Stepwise logistic regression demonstrated that independent clinical factors for ERP included age (odds ratio [OR] 0.68; P<0.001), male sex (OR 17.09; P<0.001), systolic blood pressure (SBP) (OR 0.77; P=0.022), stroke (OR 0.14; P=0.055), RR interval (OR 1.27; P=0.001), QTc interval (OR 0.76; P=0.008), QRS duration (OR 0.67; P=0.001), Cornell voltage (OR 0.28; P<0.001), and Sokolow-Lyon voltage (OR 2.03; P<0.001). ConclusionsAlthough the prevalence of ERP in general rural Chinese population is low, younger age, male sex, lower SBP, non-stroke history, longer RR interval, shorter QTc interval, shorter QRS duration, lower Cornell voltage, and higher Sokolow-Lyon voltage are independent risk factors.