Inferior Early Repolarization Research Articles

Association of early repolarization pattern and ventricular fibrillation in patients with vasospastic angina: A systematic review and meta-analysis.

BackgroundAn early repolarization (ER) pattern is a risk factor for ventricular fibrillation (VF) in patients with vasospastic angina (VSA) caused by a coronary artery spasm. However, its detailed characteristics and prognostic value for VF remain unclear. Thus, we investigated the relationship between ER and VF in patients with VSA.HypothesisThe ER pattern is associated with VF in patients with VSA.MethodsIn this systematic review and meta‐analysis, we searched PubMed, Embase, Cochrane Library, and Web of Science databases for eligible studies published between January 2011 and December 2020; 8 studies with 1761 patients were included in the final analysis.ResultsThe ER pattern significantly predicted adverse cardiovascular events (ACEs) and VF (odds ratio [OR] = 5.13, 95% confidence interval [95% CI]: 3.16–8.35, p < .00001 and OR = 5.20, 95% CI: 3.05–8.87, p < .00001). The presence of ER in the inferior leads increased the VF risk (OR = 7.80, 95% CI: 4.04–15.05, p < .00001), regardless of the J‐point morphology or type of ST‐segment elevation in the ER pattern. A horizontal/descending ST‐segment elevation was significantly associated with VF in patients with or without an ER pattern during a coronary spasm (OR = 2.28, 95% CI: 1.07–4.88, p = .03). However, obstructive coronary artery disease was unrelated to the ER pattern (OR = 0.82, 95% CI: 0.27–2.53, p = .73).ConclusionsAn ER pattern is significantly associated with an increased risk of ACE in patients with VSA. An inferior ER pattern with horizontal/descending ST‐segment elevation confers the highest risk for VF during VSA onset. Nevertheless, the ER pattern is not associated with obstructive coronary artery disease.

Two siblings with early repolarization syndrome: clinical and genetic characterization by whole-exome sequencing.

Aims The early repolarization syndrome (ERS) can cause ventricular fibrillation (VF) and sudden death in young, otherwise healthy individuals. There are limited data suggesting that ERS might be heritable. The aim of this study was to characterize the clinical phenotype and to identify a causal variant in an affected family using an exome-sequencing approach.Methods and results Early repolarization syndrome was diagnosed according to the recently proposed Shanghai ERS Score. After sequencing of known ERS candidate genes, whole-exome sequencing (WES) was performed. The index patient (23 years, female) showed a dynamic inferolateral early repolarization (ER) pattern and electrical storm with intractable VF. Isoproterenol enabled successful termination of electrical storm with no recurrence on hydroquinidine therapy during 33 months of follow-up. The index patient’s brother (25 years) had a persistent inferior ER pattern with malignant features and a history of syncope. Both parents were asymptomatic and showed no ER pattern. While there was no pathogenic variant in candidate genes, WES detected a novel missense variant affecting a highly conserved residue (p. H2245R) in the ANK3 gene encoding Ankyrin-G in the two siblings and the father.Conclusion We identified two siblings with a malignant ERS phenotype sharing a novel ANK3 variant. A potentially pathogenic role of the novel ANK3 variant is suggested by the direct interaction of Ankyrin-G with the cardiac sodium channel, however, more patients with ANK3 variants and ERS would be required to establish ANK3 as novel ERS susceptibility gene. Our study provides additional evidence that ERS might be a heritable condition.

The impact of testosterone levels on J-wave patterns observed in healthy Turkish males

Objectives: Early-repolarization (ER) and Brugada-type-ECG-patterns (BTEP) have recently been grouped under a common terminology called “J-wave patterns” (JWP) and have been associated with an increased risk of sudden-cardiac-death. Scarce data is present about the male dominance in JWP and the probable effects of gonadal hormones on cardiac ion-channel functions. We sought to evaluate the relationship of testosterone-levels and the presence of JWP in healthy Turkish-males. Methods: One hundred eighty-five healthy male volunteers between ≥18 to ≤50 years old without any cardiac disorders were evaluated. ECG, blood biochemistry and total testosterone levels were obtained together with thorough physical examination. Subjects with complete-bundle-branch-block, non-sinus-rhythms and any abnormality on cardiac examination were excluded from the study. BTEP was searched according to the EHRA/HRS 2016 Consensus Conference on V1-V3. ER on ECG was defined as J-point elevation of ≥ 0.1 mV in ≥ 2 leads in the inferior (II, III, aVF) (Inferior ER), lateral (DI, aVL, V4-6) (Lateral ER) or both (Inferolateral ER). Results: A total of 179 subjects (mean age 34.9 ± 7.9 years) were included in our analyses. Three BTEP (1.7%) and 45 ER (26%) were detected. 22 were lateral (49%), 13 inferior (29%) and 10 were (22%) inferolateral ER. JWP (+) subjects (n = 48, 27%) were demonstrating significantly lower basal heart rates (73.9 ± 11bpm vs 68.4 ± 10.3 bpm, p = 0.001) and longer PR intervals (153.9 ± 20.3 ms vs 163.3 ± 21.6 ms, p = 0.01). JWP (+) subjects had significantly higher testosterone levels compared with the ones without (485.5 ± 128.3 ng/dl vs 559.3 ± 167.7, p &amp;lt; 0.001). In the subgroup analyses, BTEP and inferior/inferolateral ER patterns were significantly associated with higher testosterone levels compared with the JWP (-) population, while testosterone levels of subjects with lateral ER was not significantly higher. Electrolytes and blood chemistry values were non-significant between JWP + and - subjects. In the ROC analysis, the cut-off value for predicting the presence of a JWP on ECG was 629 ng/dl with a sensitivity of 44% and specificity of 86% [AUC = 0.66 (95% CI: 0.56-0.75), p = 0.001]. In multivariate analysis, total testosterone level &amp;gt; 629 ng/dl was significantly predicting a JWP on ECG, even outperforming age and hs-CRP levels with an OR of 4.57 (95% CI 1.910-10.9, p = 0.001). Conclusions: Testosterone might be associated with the male predominance observed in the JWP. More malignant inferior/inferolateral ER seems to be mainly associated with the high testosterone levels in Turkish male population. This finding might be attributed to the previously demonstrated effects of testosterone on cardiac ion-channel functions, especially outward-K channels.

Prevalence and electrophysiological phenotype of rare SCN5A genetic variants identified in unexplained sudden cardiac arrest survivors.

To determine the prevalence and in vitro electrophysiological (EP) phenotype of ultra-rare SCN5A variants of uncertain significance (VUS) identified in unexplained sudden cardiac arrest (SCA) survivors. Retrospective review of 73 unexplained SCA survivors was used to identify all patients that underwent a form of genetic testing that included comprehensive SCN5A analysis. Ultra-rare SCN5A variants (minor allele frequency < 0.005) were adjudicated according to the 2015 American College of Medical Genetics and Genomics (ACMG) guidelines. Variants designated as VUS were expressed heterologously and characterized using the whole-cell patch clamp technique. Overall, 60/73 (82%; the average age at SCA 28 ± 12 years) unexplained SCA survivors had received SCN5A genetic testing. Of these, 5/60 (8.3%) had an ultra-rare SCN5A variant. All SCN5A variants were classified as VUS. Whereas the single SCN5A VUS (p.Asp872Asn-SCN5A) identified in an unexplained SCA survivor with PR interval prolongation and inferior early repolarization conferred a loss-of-function phenotype (46.2% reduction in peak current density; 16 ms slower recovery from inactivation), the four other SCN5A VUS (p.Glu30Gly-SCN5A, p.Gln245Lys-SCN5A, p.Pro648Leu-SCN5A, and p.Glu1240Gln-SCN5A) identified in unexplained SCA survivors without early repolarization/conduction delay were indistinguishable from wild-type Nav1.5 channels. In the absence of a phenotype(s) potentially attributable to sodium channel dysfunction, all SCN5A VUS identified in unexplained SCA survivors conferred a wild-type EP phenotype in vitro. As the background rate of SCN5A genetic variation is not trivial, great care must be taken to avoid prioritizing genotype over phenotype when attempting to ascertain the root cause of an individual's SCA.

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 45 408 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.

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.

High prevalence of early repolarization in the paediatric relatives of sudden arrhythmic death syndrome victims and in normal controls.

Elevation of the ECG J-point in the inferior and lateral leads (early repolarization) has been described in survivors of ventricular fibrillation (VF) arrest and occurs in adult first-degree relatives of sudden cardiac death (SCD) probands at a frequency significantly greater than in controls, raising the possibility that this could represent an independent risk factor in the aetiology of SCD. However, data on early repolarization in the paediatric population are lacking. This study aimed to assess the prevalence of early repolarization in paediatric first-degree relatives of sudden arrhythmic death syndrome (SADS) victims. Paediatric relatives (aged <18 years) of SADS probands referred to the Inherited Arrhythmia Clinic at Great Ormond Street Hospital had their initial screening ECG reviewed for evidence of J-point elevation. J-point elevation was defined as QRS-ST slurring or a discrete notch in two or more inferior (II, III, aVF) or lateral (I, aVL, V4, V5, V6) leads with the change beginning >1 mV from baseline. The ECGs of 77 consecutive paediatric first-degree relatives of SADS victims from 46 families were reviewed by two assessors. J-point elevation was present in 24 patients (31%) of this patient group compared with the reported prevalence of 5-13% in the published general paediatric population (P = 0.02) and that of 19% in the internal control group (P = 0.07). Subgroup analysis according to J-point elevation and ST segment morphologies showed a significantly higher prevalence of inferior early repolarization 0.1-0.2 mV in the study group compared with controls (75 vs. 38%; P = 0.02). Inferolateral J-point elevation occurs in a substantial proportion of paediatric first-degree relatives of SADS probands with a similar prevalence to that described in adults. This suggests that early repolarization could be an important inherited trait when evaluating relatives of SADS victims. However, prospective follow-up of this group of children is important to establish the implication of this finding in future risk stratification, given the apparently high prevalence in normal individuals.

Diagnosis of arrhythmogenic cardiomyopathy by localized right precordial QRS prolongation and inferior early repolarization phenomenon but without T-wave inversion

Article history: Received 28 November 2015 Accepted 1 January 2016 Available online 6 January 2016 localized right ventricular QRS prolongation. The right precordial T wave inversion is a major criterion of arrhythmogenic cardiomyopathy, but early repolarization phenomenon with localized inferior QRS prolongation is a very good hint for arrhythmogenic cardiomyopathy, too [5]. Both–T wave inversion and early repolarization phenomenon–are repolarization criteria

Notching early repolarization pattern in inferior leads increases risk of ventricular tachyarrhythmias in patients with acute myocardial infarction: a meta-analysis.

The aim of this of this meta-analysis was to examine the potential association between certain early repolarization (ER) characteristics and ventricular tachyarrhythmias (VTAs) in patients with acute myocardial infarction (AMI). We searched PubMed, Embase and Web of Science databases for records published until December 2014. Of the 658 initially identified records, 7 studies with a total of 1,565 patients (299 with ER and 1,266 without ER) were finally analyzed. Overall, patients with ER displayed a higher risk of VTAs following AMI compared to patients without ER [odds ratio (OR): 3.75, 95% CI: 2.62–5.37, p < 0.00001]. Subgroup analyses showed that the diagnosis of ER prior to AMI onset is a better predictor of VTAs (OR: 5.70, p < 0.00001) compared to those diagnosed after AMI onset (OR: 2.60, p = 0.00001). Remarkably, a notching morphology was a significant predictor of VTAs compared to slurring morphology (OR: 3.85, p = 0.002). Finally, an inferior ER location (OR: 8.85, p < 0.00001) was significantly associated with increased risk of VTAs in AMI patients. In conclusion, our meta-analysis suggests that ER pattern is associated with greater risk of VTAs in patients with AMI. A notched ER pattern located in inferior leads confers the highest risk for VTAs in AMI.

Management of an asymptomatic patient with dynamically changing J wave from inferior early repolarization to Brugada pattern

Case report A 33-year-old man was referred to our institution for investigation of type 1 Brugada syndrome (BS) fortuitously discovered on a routine electrocardiogram (ECG) recorded at an occupational medicine clinic. The patient had no family history of structural heart disease or sudden death and no personal medical history. He was completely asymptomatic at the time of the initial examination. The 12-lead ECG at admission (Figure 1) reveals a normal sinus rhythm with a significant ST-segment elevation of more than 2 mm in leads V1 and V2 diagnostic of a type 1 BS. We also noted the presence of a significant slurred J wave in the inferior leads diagnostic of early repolarization (ER) pattern. At baseline, the maximal amplitude of the J wave was 5 mm (0.5 mV) in lead V1 and 4 mm (0.4 mV) in lead III. As we performed routine Valsava maneuvers, we observed significant change in the J wave in amplitude and distribution (Figure 2). Immediately after the end of maneuvers the J wave became maximal in the inferior leads and extended all the way to the T wave (amplitude of 5 mm in lead III) while J wave decreased in the anterior leads (disappeared in lead V1 and maximal amplitude of 4 mm in lead V2). Rapidly after the end of the Valsalva maneuver, a gradual transition of the ECG back to its initial form was subsequently observed. The same phenomenon was obtained reproducibly with Valsalva maneuvers. Multiple ECG recordings and continuous heart rhythm telemetry also demonstrated extreme fluctuation of the J wave in amplitude and distribution from predominant Brugada pattern to predominant ER pattern to normal ECG (Figure 3). During hospitalization, the patient underwent an extensive cardiac

Early repolarization patterns associated with increased arrhythmic risk are common in young non-Caucasian Australian males and not influenced by athletic status.

Early repolarization (ER) with a horizontal ST segment (ST-h) and high-amplitude J waves in the inferior leads is associated with an increased risk of cardiac arrhythmic death. The effect of ethnicity and athletic status on this increased-risk ER pattern has not been established. Aboriginal Australian/Torres Strait Islander and Pacific Islander/Maori (non-Caucasian [non-C]) subjects are well represented in Australian sport; however, the patterns and prevalence of ER in these populations are unknown. The purpose of this study was to assess the prevalence and effect of athletic activity on ER patterns in young non-C and Caucasian (C) subjects. Twelve-lead ECGs of 726 male athletes (23.8% non-C) and 170 male controls (45.9% non-C) aged 16-40 years were analyzed for the presence of ER, defined as J-point elevation (J wave, QRS slur, or discrete ST elevation) ≥0.1 mV in ≥2 inferior (II, III, aVF) or lateral (I, aVL,V4-V6) leads. ST morphology was coded as horizontal (ST-h) or ascending (ST-a). "Increased-risk ER" was defined as inferior ER with ST-h and J waves >2 mV. Regardless of athletic status, ER and increased-risk ER were more prevalent in non-C than in C subjects (53.8% vs 32% and 7.6% vs 1.2%, respectively, P <.0001). Whereas lower heart rate, larger QRS voltage, and shorter QRS duration were predictors of ER, non-C ethnicity was the only independent predictor of increased-risk ER (odds ratio 17.621, 95% confidence interval 4.98-62.346, P < .0001). ER patterns associated with increased arrhythmic risk are more common in young non-C than C subjects and were not influenced by athletic status. The long-term clinical significance of ER in these populations is yet to be determined.

Early repolarization as a predictor of arrhythmic and nonarrhythmic cardiac events in middle-aged subjects.

Early repolarization (ER) in the inferior/lateral leads predicts mortality, but whether ER is a specific sign of increased risk for arrhythmic events is not known. The purpose of this study was to study the association of ER and arrhythmic events and nonarrhythmic morbidity and mortality. We assessed the prognostic significance of ER in a community-based general population of 10,846 middle-aged subjects (mean age 44 ± 8 years). The end-points were sustained ventricular tachycardia or resuscitated ventricular fibrillation (VT-VF), arrhythmic death, nonarrhythmic cardiac death, new-onset atrial fibrillation (AF), hospitalization for congestive heart failure, or coronary artery disease during mean follow-up of 30 ± 11 years. ER was defined as ≥0.1-mV elevation of J point in either inferior or lateral leads. After including all risk factors of cardiac mortality and morbidity in Cox regression analysis, inferior ER (prevalence 3.5%) predicted VF-VT events (n = 108 [1.0%]) with a hazard ratio (HR) of 2.2 (95% confidence interval [CI] 1.1-4.5, P = .03) but not nonarrhythmic cardiac death (n = 1235 [12.2%]), AF (n = 1659 [15.2%]), congestive heart failure (n = 1752 [16.1%]), or coronary artery disease (n = 3592 [32.9%]) (P = NS for all). Inferior ER predicted arrhythmic death in cases without other QRS complex abnormalities (multivariate HR 1.68, 95 % CI 1.10-2.58, P = .02) but not in those with ER and other coexisting abnormalities in QRS morphology (HR 1.30, 95% CI 0.86-1.96, P = .22). ER in the inferior leads, especially in cases without other QRS complex abnormalities, predicts the occurrence of VT-VF but not nonarrhythmic cardiac events, suggesting that ER is a specific sign of increased vulnerability to ventricular tachyarrhythmias.

Early repolarization and myocardial scar predict poorest prognosis in patients with coronary artery disease.

PurposeRecent studies show positive association of early repolarization (ER) with the risk of life-threatening arrhythmias in patients with coronary artery disease (CAD). This study was to investigate the relationships of ER with myocardial scarring and prognosis in patients with CAD.Materials and MethodsOf 570 consecutive CAD patients, patients with and without ER were assigned to ER group (n=139) and no ER group (n=431), respectively. Myocardial scar was evaluated using cardiac single-photon emission computed tomography.ResultsER group had previous history of myocardial infarction (33% vs. 15%, p<0.001) and lower left ventricular ejection fraction (57±13% vs. 62±13%, p<0.001) more frequently than no-ER group. While 74 (53%) patients in ER group had myocardial scar, only 121 (28%) patients had in no-ER group (p<0.001). During follow up, 9 (7%) and 4 (0.9%) patients had cardiac events in ER and no-ER group, respectively (p=0.001). All patients with cardiac events had ER in inferior leads and horizontal/descending ST-segment. Patients with both ER in inferior leads and horizontal/descending ST variant and scar had an increased adjusted hazard ratio of cardiac events (hazard ratio 16.0; 95% confidence interval: 4.1 to 55.8; p<0.001).ConclusionER in inferior leads with a horizontal/descending ST variant was associated with increased risk of cardiac events. These findings suggest that ER in patients with CAD may be related to myocardial scar rather than pure ion channel problem.

Gender modulates the aging effects on different patterns of early repolarization

Distinct patterns of early repolarization (ER) are associated with ventricular fibrillation and arrhythmic death. We evaluated whether gender modulated the aging effects on different ER patterns. We studied manifestations of ER in the anterior, inferior, and lateral leads on standard 12-lead electrocardiography from male (n = 1077) and female (n = 1170) individuals of young (≤44 years), middle-aged (45-64 years), and elderly (≥65 years) subjects. Among a total of 2247 individuals, 543 (24.2 %) subjects had ER and 417 (18.6 %) had single-location ER. Single-location ER occurred less in lateral leads than in anterior or inferior leads (2.1, 7.8, 8.6 %, respectively, p < 0.05). Subjects with inferior ER (n = 193) were older (61 ± 14, 49 ± 14, 54 ± 16 years, respectively, p < 0.05) than those with anterior (n = 176) or lateral (n = 48) ER. In males with ER, the elderly group (n = 22) had fewer instances of anterior ER (34, 59, 80 %, respectively, p < 0.05) than middle-aged (n = 76) or young (n = 59) groups. Elderly males (n = 37) and females (n = 48) had greater instances of inferior ER (57, 32, 19 %, p < 0.05; 86, 62, 46 %, respectively, p < 0.05) than middle-aged males (n = 41) and females (n = 41), and young males (n = 14) and females (n = 12), respectively. In conclusion, gender modulates the aging effects on the occurrences of anterior ER and inferior ER.

Characterization of early repolarization during ajmaline provocation and exercise tolerance testing

Early repolarization (ER) in the inferior electrocardiogram leads is associated with idiopathic ventricular fibrillation, but the majority of subjects with ER have a benign prognosis. At present, there are no risk stratifiers for asymptomatic ER. To examine the response to ajmaline provocation and exercise in potentially high-risk subjects with ER and without a definitive cardiac diagnosis. Electrocardiographic data were reviewed for ER at baseline and during ajmaline and exercise testing in 229 potentially high-risk patients (mean age 37.7±14.9 years; 55.9% men). ER was defined as J-point elevation in ≥2 consecutive leads and stratified by type, territory, J-point height, and ST-segment morphology. Baseline ER was present in 26 (11.4%; 19 men) patients. During ajmaline provocation and exercise, there were no new ER changes. ER with rapidly ascending ST-segment and lateral ER consistently diminished. There were 7 patients with persistent ER during ajmaline and/or exercise. They were all men with inferior or inferolateral ER and horizontal/descending ST segment. Those with persistent ER during exercise were more likely to have a history of unexplained syncope than those in whom ER changes diminished (P<.01). Subtle nondiagnostic structural abnormalities were demonstrated in 3 of these patients. ER with horizontal/descending ST-segment morphology in the inferior or inferolateral leads that persists during exercise is more common in patients with prior unexplained syncope and may identify patients at higher risk of arrhythmic events. ER that persists during ajmaline provocation and/or exercise may reflect underlying subtle structural abnormalities and should prompt further investigation.

Natural History of Early Repolarization in the Inferior Leads

Though early repolarization (ER) in the inferior leads has been associated with increased cardiovascular risk, its natural history is uncertain. We aimed to study the serial electrocardiographic behavior of inferior ER and understand factors associated with that behavior. We selected electrocardiograms (ECGs) from patients with the greatest amplitude of ER in AVF from ECGs of 29,281 ambulatory patients recorded between 1987 and 1999 at the Palo Alto Veterans Affairs Hospital. Starting from the highest amplitude, we reviewed the ECGs and medical records from the first 85%. From this convenience sample, 36 were excluded for abnormal patterns similar to ER. The remaining 257 patients were searched for another ECG at least 5 months later, of whom, 136 satisfied this criteria. These ECGs were paired for comparison and coded by four interpreters. The average time between the first and second ECGs was 10 years. Of the 136 subjects, 47% retained ER while 53% no longer fulfilled the amplitude criteria. While no significant differences were found in initial heart rate (HR) or time interval between ECGs, those who lost the ER pattern had a greater difference in HR between the ECGs. There was no significant difference in the incidence of cardiovascular events or deaths. In conclusion, the ECG pattern of ER was lost over 10 years in over half of the cohort. The loss of ER was partially explained by changes in HR, but not higher incidence of cardiovascular events or death, suggesting the entity is a benign finding.

Wolff-Parkinson-White Syndrome Concomitant with Idiopathic Ventricular Fibrillation Associated with Inferior Early Repolarization

We encountered a 39-year-old man with documented ventricular fibrillation (VF). His ECGs showed intermittent Wolff-Parkinson-White (WPW) syndrome pattern. During electrophysiological study, no ventricular preexcitation was observed. An accessory pathway located at the posterior mitral annulus was identified, and successfully eliminated by radiofrequency catheter ablation. VF was not induced. His ECGs in the absence of delta waves demonstrated early repolarization in the inferior leads. This case raises the possibility that patients with manifest WPW syndrome may have an arrhythmogenic substrate associated with early repolarization, and the characteristic J waves can be masked by the presence of ventricular preexcitation.

Letter by Bastiaenen and Behr Regarding Article, “Early Repolarization: Electrocardiographic Phenotypes Associated With Favorable Long-Term Outcome”

To the Editor: Early repolarization (ER) was historically considered a benign ECG variant, commonly seen in the anterolateral leads of young male athletes of black ethnicity. It was defined by Wasserburger and Alt1 in 1961 as elevated take-off of the ST segment at the J junction with downward concavity of the ST segment and symmetrical T waves. In recent years it has emerged as a marker for increased risk of sudden cardiac death, particularly in the inferior ECG leads.2,3 Although ER is a common ECG finding, ER syndrome (ER with idiopathic ventricular fibrillation) is rare.2 Even in middle-aged individuals with inferior ER of ≥0.2 mV, the 3-fold …

Benign or malignant, early or delayed: the changing face of early repolarization

Early repolarization (ER) has historically been considered a benign electrocardiogram (ECG) variant, and is seen more commonly in young males and individuals who undertake high levels of athletic activity and/or are of black ethnicity.1 It has recently, however, been proposed as a marker for an increased risk of sudden cardiac death (SCD). In particular, ER in the inferior ECG leads has been associated with idiopathic ventricular fibrillation and has been termed as the ER syndrome.2,3 Although ER is a common ECG finding, the syndrome is rare. Indeed in a general population study, middle-aged individuals with inferior ER only had a three-fold increased risk of SCD which was not apparent until 10 years after their initial diagnostic ECG.3 Until recently, there have been no risk stratifiers for asymptomatic subjects with ER and no primary prevention therapy. Much of this has been complicated by uncertainties over the definition of ER, how to measure it, and its actual causation. It has therefore been impossible to make recommendations based on this incidental ECG finding in an asymptomatic individual and this has become a concern for the cardiology community. ### Historical perspectives and definitions The definition of ER has evolved. It was defined by Wasserburger1 in 1961 as elevated take-off of the ST-segment at the end of the QRS (the J junction) with downward concavity of the ST-segment and symmetrical T-waves seen particularly in the lateral ECG leads ( Figure 1C ). In 2008, it …