Prevalence Of Early Repolarization Research Articles

Identification of Large Families in Early Repolarization Syndrome

The aim of this study was to identify families affected by early repolarization syndrome (ERS) and to determine the mode of transmission of the disease. Early repolarization (ER) has recently been linked to idiopathic ventricular fibrillation. Familial inheritance of the disease has been suggested but not demonstrated. We screened relatives of 4 families affected by ERS. ER was defined as a distinct J-wave in at least 2 consecutive leads and a 1-mm amplitude above baseline. The Valsalva maneuver was performed in affected and unaffected family members to decrease heart rate and thus increase or reveal an ER pattern. Twenty-two sudden cardiac deaths occurred in the 4 families including 10 before 35 years of age. In the 4 families, the prevalence of ER was 56%, 34%, 61%, and 33% of, respectively, 30, 82, 29, and 30 screened relatives. In these families, transmission of an ER pattern is compatible with an autosomal dominant mode of inheritance. All probands were screened for genes identified in ERS, and no mutation was found. The Valsalva maneuver was performed in 80 relatives, resulting in increased J-wave amplitude for 17 of 20 affected patients and revealing an ER pattern in 17 relatives in whom 5 are obligate transmitters of an ER pattern. ERS can be inherited through autosomal dominant transmission and should be considered a real inherited arrhythmia syndrome. Familial investigation can be facilitated by using the Valsalva maneuver to reveal the electrocardiographic pattern in family members. The prognosis value of this test remains to be assessed.

Early repolarization with horizontal ST segment may be associated with aborted sudden cardiac arrest: a retrospective case control study

BackgroundRisk stratification of the early repolarization pattern (ERP) is needed to identify malignant early repolarization. J-point elevation with a horizontal ST segment was recently suggested as a malignant feature of the ERP. In this study, the prevalence of the ERP with a horizontal ST segment was examined among survivors of sudden cardiac arrest (SCA) without structural heart disease to evaluate the value of ST-segment morphology in risk stratification of the ERP.MethodsWe reviewed the data of 83 survivors of SCA who were admitted from August 2005 to August 2010. Among them, 25 subjects without structural heart disease were included. The control group comprised 60 healthy subjects who visited our health promotion center; all control subjects were matched for age, sex, and underlying disease (diabetes mellitus, hypertension). Early repolarization was defined as an elevation of the J point of at least 0.1 mV above the baseline in at least two continuous inferior or lateral leads that manifested as QRS slurring or notching. An ST-segment pattern of <0.1 mV within 100 ms after the J point was defined as a horizontal ST segment.ResultsThe SCA group included 17 men (64%) with a mean age of 49.7 ± 14.5 years. The corrected QTc was not significantly different between the SCA and control groups (432.7 ± 37.96 vs. 420.4 ± 26.3, respectively; p = 0.089). The prevalence of ERP was not statistically different between the SCA and control groups (5/25, 20% vs. 4/60, 6.7%, respectively; p = 0.116). The prevalence of early repolarization with a horizontal ST segment was more frequent in the SCA than in the control group (20% vs. 3.3%, respectively; p = 0.021). Four SCA subjects (16%) and one control subject (1.7%) had a J-point elevation of >2 mm (p = 0.025). Four SCA subjects (16%) and one (1.7%) control subject had an ERP in the inferior lead (p = 0.025).ConclusionThe prevalence of ERP with a horizontal ST segment was higher in patients with aborted SCA than in matched controls. This result suggests that ST morphology has value in the recognition of malignant early repolarization.

The Prevalence of Early Repolarization in Patients with Noncompaction Cardiomyopathy Presenting with Malignant Ventricular Arrhythmias

Early Repolarization in Noncompaction Cardiomyopathy. Early repolarization (ER) is associated with malignant ventricular arrhythmias, including ventricular fibrillation (VF) and sudden cardiac death (SCD). One possible mechanism is increased trabeculation with deep intramyocardial invagination, carrying the Purkinje system deeper into the myocardium resulting in delayed depolarization and inhomogenous repolarization. Noncompaction cardiomyopathy (NCCM) is a recently classified, primary cardiomyopathy with excessive trabeculations. In these patients ventricular arrhythmias, including sustained VT and VF, occur frequently. The aim of this study was to determine the prevalence of ER in NCCM patients, especially in those primarily presenting with malignant ventricular arrhythmias or SCD. We analyzed prospective data from our NCCM registry including 84 patients, median age: 40 (3-79) years. Fourteen patients (17%) initially presented with sustained VT (n = 5) or VF (n = 9) and 70 (83%) with heart failure or else. After the exclusion of 20 patients with the left bundle branch block, 25 (39%) NCCM patients had ER; 3 (6%) located in inferior leads, 14 (27%) in lateral leads, and 8 (15%) in both. None had ER in leads V1 to V3. In those presenting with VT/VF, 9/12 (75%) had ER (2 in inferior leads, 3 in lateral leads and 4 in both), versus 16/52 (31%) in the other patients (P = 0.02). If the NCCM population was dichotomized according to the presence or absence of ER, the long-term outcome for VT/VF appeared worse in the ER positive patients (P = 0.05). There is a high prevalence of ER in NCCM patients, especially in those who present with malignant ventricular arrhythmias. (J Cardiovasc Electrophysiol, Vol. 23, pp. 938-944, September 2012).

PROGNOSTIC IMPLICATIONS OF Q WAVES AND T WAVE INVERSION ASSOCIATED WITH EARLY REPOLARIZATION

Recent studies suggest an association between early repolarization (ER) and increased cardiovascular mortality. It has been reported, however, that this mortality is due to associated ECG abnormalities rather than the ER itself. Thus, given the high prevalence of ER, defining its associated risk

The prevalence of early repolarization in Wolff-Parkinson-White syndrome with a special reference to J waves and the effects of catheter ablation

We determined the prevalence of J waves in the electrocardiograms (ECG) of 120 patients with Wolff-Parkinson-White syndrome in comparison with J-wave prevalence in a control group of 1936 men and women with comparable demographic and ECG characteristics and with normal atrioventricular conduction. J waves were present only during manifest preexcitation in 22 of 120 patients (18.3%), disappearing after catheter ablation and suggesting that J waves were associated with the presence of preexcitation. J waves were present in 19 (15.8%) of 120 patients only after ablation, apparently having been masked by early depolarization of the preexcited myocardial region, and in 22 patients (18.3%), J waves were not altered significantly by preexcitation. Thus, the overall J-wave prevalence was 52.5% (63/120) and, excluding those apparently due to preexcitation, 34.8% (41/120), both substantially higher than the prevalence (11.5%) in the control group ( P < .001 for both). The patients with J waves appearing only during preexcitation were younger, predominantly females. The presence of J waves after ablation was associated with a history of atrial fibrillation and shorter ventricular effective refractory period. It is concluded that the prevalence of J waves is high in patients with Wolff-Parkinson-White syndrome and is influenced by manifest preexcitation.

Early repolarization in Wolff-Parkinson-White syndrome: prevalence and clinical significance

Idiopathic ventricular fibrillation (IVF) with early repolarization (ER) has recently been reported; however, ER is a common finding in healthy subjects and is also found sporadically in patients with Wolff-Parkinson-White (WPW) syndrome. The present study was designed to evaluate the prevalence and clinical significance of ER in patients with WPW syndrome. One hundred and eleven patients with WPW syndrome were studied retrospectively. Early repolarization was defined as QRS slurring or notching with J-point elevation ≥ 1 mm. The prevalence of ER was determined before and after successful catheter ablation. Before ablation, ER was found in 35 of 75 patients with a left free wall, 6 of 23 with a right free wall, and 7 of 13 with a septal accessory pathway (48 of 111, 43% as a whole). Early repolarization was always observed in leads with positive deflection of the initial part of the delta wave. After successful ablation of accessory pathways, ER was preserved in 28 (25%), disappeared in 20 (18%), and newly developed in 8 (7%) patients. In the remaining 55 (50%) patients, ER was not observed either before or after ablation. In patients with persistent ER, the amplitude and width of ER were significantly decreased 3-7 days after the ablation (1.7 ± 0.7 vs. 1.4 ± 0.6 mm, P < 0.005 and 42 ± 11 vs. 34 ± 9 ms, P < 0.001, respectively). In patients with WPW syndrome, ER could be partly related to early depolarization through the accessory pathway. However, persistent ER and new ER appearing after the ablation were frequently found. Therefore, in these patients, mechanisms other than early depolarization may be involved in the genesis of ER.

Heritability of Early Repolarization

Background— Early repolarization (ER), defined by J-point elevation in 12-lead ECG, was recently associated with increased risk for idiopathic ventricular fibrillation and cardiovascular mortality. The determinants of ER are unknown. We investigated its heritability in a large, family-based cohort. Methods and Results— The study sample comprised 1877 individuals from 505 white nuclear families representative of the British general population. Standard 12-lead ECGs were evaluated for the presence of ER, defined as J-point elevation of ≥0.1 mV in at least 2 adjacent inferior (II, III, and aVF) or anterolateral (I, aVL, and V 4 through V 6 ) leads. Narrow sense heritability estimates were computed adjusting for age, age 2 , and sex. The prevalence of ER was 7.7% (n=145) in the whole cohort, 5.9% (n=56) in parents, and 9.6% (n=89) in offspring. Heritability estimate for the presence of ER was calculated at h 2 =0.49 (standard error=0.14; P =2.7*10 −4 ) and was higher when restricted to its presence in inferior leads (h 2 =0.61, standard error=0.18, P =4.3*10 −4 ) or for the notching ER morphology (h 2 =0.81, standard error=0.19, P =2.4*10 −5 ). Individuals with at least 1 affected parent had a 2.5-fold increased risk for presenting with ER on ECG (odds ratio, 2.54; 95% confidence interval, 1.33 to 4.84; P =0.005). Familial transmission was more frequent when the mother was affected (odds ratio, 3.84; 95% confidence interval, 1.41 to 10.43; P =0.008) than when the father was affected (odds ratio, 1.82; 95% confidence interval, 0.82 to 4.03; P =0.141), although this difference was not statistically significant ( P =0.18). Conclusions— ER is a heritable phenotype. Offspring of ER-positive parents have a 2.5-fold increased risk of presenting with ER on their ECG.

Early repolarization in children with unexplained syncope

Introduction: It has traditionally been believed that early repolarization (ER) is benign. Significant association between ER and sudden cardiac arrest due to idiopathic ventricular fibrillation was recently found in a large cohort of adult survivors of sudden cardiac arrest. In some prior studies, unexplained syncope has been linked to risk of sudden death, but the mechanisms remain speculative.We assessed herein the prevalence of ER in children referred to our center for unexplained syncope. Methods: We evaluated retrospectively electrocardiograms from such children (n = 29; mean age, 12.1 years; range, 7-18 years) for presence of ER, which was defined as an elevation of the QRS-ST junction (J-point) in at least 2 leads of at least 1 mm (0.1 mV) above the baseline level. The anterior precordial leads (V1-V3) were excluded from the analysis to avoid inclusion of patients with right ventricular dysplasia or Brugada syndrome. Agematched children (n = 33; mean age, 12.3 years; range, 7-16 years) with noncardiac chest pain were included as controls. Results: Early repolarization was detected in 45% (13/29) of children with unexplained syncope vs 24% (8/33) in the chest pain group. Among children with syncope, ER was far more frequent in males than in females (8/12 vs 5/ 17, respectively). Echocardiography showed normal functional and structural findings in all children. Conclusion: In this relatively small-scale retrospective study of children with unexplained syncope with otherwise normal cardiac findings, we found particularly among those of male gender a greater prevalence of ER than in controls (noncardiac chest pain).With view to earlier findings of Haisaguerre et al (NEJM 2008), this intriguing association warrants further prospective studies addressing its precise clinical implication and underlying mechanisms. (Less)

Prevalence of Early Repolarization in Acute Period after Cardiac Defibrillation

Prevalence of Early Repolarization in Acute Period after Cardiac Defibrillation

Early Repolarization Is a Risk Marker of Ventricular Fibrillation and Prognosis in Anterior Acute Myocardial Infarction

Background: In patients without structural heart disease, the presence of early repolarization on ECG is associated with ventricular fibrillation (VF). However, it is unclear the correlation between early repolarization and VF in patients with acute myocardial infarction (AMI). Methods: We studied 162 patients with first-anterior-acute-ST-elevation MI received percutaneous coronary intervention, and evaluated ECG after successful reperfusion. Early repolarization was defined as an elevation of the QRS-ST junction of >0.1 mV from baseline in the inferior or lateral lead. VF was defined as that not terminated spontaneously and required electrical cardioversion. Patients were classified into two groups (VF group and non-VF group). Results: VF occurred in 22 patients (13.6%). Early repolarization was present in 47 of the 162 patients (29%). The prevalence of early repolarization was significantly higher (54.5% vs. 25%; p 2 (β-coefficient 0.31 (95%CI; 0.179 to 0.448), p<0.01) and early repolarization (β-coefficient 0.18 (95%CI; 0.074 to 0.289), p<0.01). Conclusions: Despite degree of initial TIMI flow grade, the presence of infero-lateral early repolarization may be a potential risk factor for VF leading to poor prognosis in anterior AMI patients.

Inferolateral early repolarization in athletes

Early repolarization (ER) has been considered a common benign ECG pattern among young athletes. In contrast, an inferolateral early repolarization pattern has been associated with an increased risk for sudden cardiac death (SCD). The aim of the study was to assess the prevalence of inferolateral ER among young collegiate athletes and to describe the characteristics associated to the pattern. We analyzed ECGs from 503 athletes (51% males; age range, 17-24). Information on gender, body weight, race, sport, and family history of SCD was collected. ER was defined as a slow deflection of the down slope of the R wave (≥0.1mV) or positive wave at J point (≥0.1mV) in two consecutive inferior or in lateral leads. Additionally, we included voltage measurements according to the Sokolow-Lyon criteria and RR interval measurement. The prevalence of ER was 30% (inferior, 20%; lateral, 21%; both, 11%). Male gender (59% vs. 48%, p = 0.019), left ventricular hypertrophy (LVH) voltage (39% vs. 12%, p < 0.001) was significantly associated with the ER pattern. In addition, there was a trend towards longer RR interval in the inferior ER group (p = 0.06) and there were slightly more African-Americans with ER compared to non-African-American (34% vs. 28%, p = 0.22). Among females (p = 0.039) and African-Americans (p = NS), the association of LVH to ER was not as strong. ER is a common finding among young athletes. The ECG marker of LVH is the dominant shared characteristic among the athletes with ER, along with male gender and a trend to greater prevalence among African-American athletes.

Prevalence and QT Interval of Early Repolarization in a Hospital-based Population

Background: Early repolarization, which was regarded as benign, has recently been associated with malignant arrhythmia. Despite the newly emerged importance of early repolarization, little is known about prevalence and QT interval of early repolarization. Methods: Early repolarization (defined as an elevation at the junction between QRS complex and ST segment ≥ 0.1 mV in at least 2 leads) was assessed in database containing 308,391 ECGs consisting of 102,065 patients (52,779 males and 49,286 females).Results: A total of 1,775 patients (mean age, 49 ± 30 years) with early repolarization were chosen (1.7% of total population). The prevalence of early repolarization was about 11‐times higher in male patients (n = 1,623) than in female patients (n = 152). The prevalence of early repolarization was 1.4% at the age of 0‐9 years, peaked (5.0%) at the age of 10‐19 years, and progressively decreased with advancing age from 20 to 79 years (3.3, 2.1, 1.6, 0.9, 0.5, and 0.3% at the age of 20‐29, 30‐39, 40‐49, 50‐59, 60‐69, and 70‐79 years, respectively). Bazett's QTc interval of patients with early repolarization did not significantly differ among groups of each decade and between genders.Conclusion: The prevalence of early repolarization was both age‐ and gender‐dependent in a hospital‐based population. Yet, there was no association between QTc interval and age and between QTc interval and gender.

Prevalence and QT Interval of Early Repolarization in a Hospital-based Population

Background: Early repolarization, which was regarded as benign, has recently been associated with malignant arrhythmia. Despite the newly emerged importance of early repolarization, little is known about prevalence and QT interval of early repolarization. Methods: Early repolarization (defined as an elevation at the junction between QRS complex and ST segment ≥ 0.1 mV in at least 2 leads) was assessed in database containing 308,391 ECGs consisting of 102,065 patients (52,779 males and 49,286 females). Results: A total of 1,775 patients (mean age, 49 ± 30 years) with early repolarization were chosen (1.7% of total population). The prevalence of early repolarization was about 11-times higher in male patients (n = 1,623) than in female patients (n = 152). The prevalence of early repolarization was 1.4% at the age of 0-9 years, peaked (5.0%) at the age of 10-19 years, and progressively decreased with advancing age from 20 to 79 years (3.3, 2.1, 1.6, 0.9, 0.5, and 0.3% at the age of 20-29, 30-39, 40-49, 50-59, 60-69, and 70-79 years, respectively). Bazett's QTc interval of patients with early repolarization did not significantly differ among groups of each decade and between genders. Conclusion: The prevalence of early repolarization was both age- and gender-dependent in a hospital-based population. Yet, there was no association between QTc interval and age and between QTc interval and gender.

Early Repolarization In Patients With Spinal Cord Injury: Prevalence And Clinical Significance

Objectives: The objective was to examine the prevalence of early repolarization in a spinal cord injury (SCI) clinic and the relationship of level of injury to this electrocardiogram (ECG) finding.Background: ST elevation on the resting ECG can be either a normal variant or a sign of acute ischemia, evolving myocardial infarction, or pericarditis. It is frequently seen as a normal variant (early repolarization) in healthy individuals, but has also been reported in individuals with SCI. While the etiology of benign ST elevation (early repolarization) has not been clearly defined, current opinion is that this finding is seen in individuals with high vagal tone.Methods: Retrospective analysis was made of 315 individuals with SCI at T5 or above (140 with complete injuries), and 198 with SCI at T6 or below, and who had ECGs in the computerized database at the Palo Alto VA Medical Center. A comparison cohort of 32,841 able-bodied male controls also was identified in the same ECG database. Patient demographics and computerized ST measurements were analyzed.Results: The prevalence of ST elevation was significantly higher in both the total high-level injury group (19%) and the complete high-injury group (24.5%) than in either the low-injury (6.5%) or control groups (13%), with P < 0.001 for comparisons between both high- and low-injury groups and high injury vs control. The magnitude of ST elevation was also higher in the high-injury groups vs the low-injury and control groups.Conclusion: There is a higher prevalence of early repolarization in individuals with SCI at levels of injury that can disrupt central sympathetic command of the heart. It appears that either enhanced vagal tone or loss of sympathetic tone is responsible for ST elevation