Repolarization Pattern Research Articles

Refractory Angina Confounded by Preexcitation Syndrome.

Scenario: This 12-lead electrocardiogram (ECG) was obtained on a 48-year-old man who came to the emergency department with progressively worsening left lateral crushing chest pain and dyspnea of 3 hours’ duration. The patient drinks 9 beers daily, is an active smoker, and is treated for hypertension and hypercholesterolemia. His initial vital signs during prehospital transport showed a heart rate of ~110/minute and blood pressure of 151/100 mm Hg. Paramedics administered aspirin and sublingual nitroglycerin during ambulance transport, and this ECG was obtained upon arrival in the emergency department.Sinus rhythm with Wolff-Parkinson-White (WPW) syndrome type A.In the normal electrical conduction system, the atrioventricular (AV) node serves as a gatekeeper to regulate the propagation of signals from the atria into the ventricles. When an accessory pathway exists, ventricular activation occurs through both the AV node and the extra anatomical pathway, yielding a shorter PR interval and a slurred upstroke of the QRS complex (ie, delta wave). When the accessory pathway connects to the left ventricle, the preexcitation starts in the left ventricle first before it proceeds normally through the bundle of His and bundle branches (called WPW type A). This syndrome manifests as a wide QRS complex with pseudo right bundle branch block pattern (ie, tall R wave in right precordial leads). Because of the temporal heterogeneity in ventricular activation, repolarization abnormalities (or non-specific ST-segment and T-wave changes) are common, including early repolarization pattern (eg, J-point elevation best seen in lead V3 in this example). Such dispersion in ventricular depolarization and repolarization might lead to back propagation of the signal to the atria either through the bundle of His or through the accessory pathway. This back propagation may create an atrioventricular reentry circuit and sustained tachycardia. Although WPW syndrome is usually benign, curative catheter ablation is considered in symptomatic or hemodynamically unstable patients.Although secondary repolarization changes are common in WPW syndrome, the ST-segment elevation in the anterior wall that is accompanied with reciprocal changes in the inferolateral walls, coupled with the highly suspicious presenting symptoms and history, are worrisome for acute myocardial infarction. In this specific patient, the initial cardiac workup was negative, and the patient was admitted to the telemetry unit for serial ECGs and troponin assays. Owing to persistent refractory angina, the patient was referred for cardiac angiography the following morning, which revealed normal left ventricular function and mild atherosclerotic disease in the right coronary artery at 20% to 30% occlusion. The patient was discharged home on oral anti-ischemic therapy (eg, aspirin, nitroglycerin) with a referral to cardiac electrophysiology for further management of the underlying WPW syndrome. Long-term ambulatory monitoring (eg, Holter ECG) is warranted to rule out reentry tachyarrhythmias.

Evaluation of Early Repolarization Pattern in Male Teenage Competitive Athletes and Association With Left Ventricular Remodeling.

Objective:Early repolarization pattern (ERP) on electrocardiogram is more common among young athletes than in the general population, and has been considered a benign finding. However, ERP has been associated with increased risk of sudden cardiac death. The objectives of this study were to evaluate ERP in teenage athletes; investigate associations between ERP and echocardiographic findings of the left ventricle (LV); and to describe the impact of different sports disciplines on ERP.Methods:ERP was assessed in male teenage athletes from sports institutions for 5 different types of sport––basketball, swimming, football, wrestling, and tennis. All had been training for at least 3 hours per week for over at least 2 years. ERP was defined as J-point elevation ≥ 1 mV in 2 contiguous and/or lateral leads. A conventional echocardiography was performed in all athletes.Results:ERP was evaluated in 159 athletes with a mean age of 14 (range 10-18 years). It was more common in those training with combined exercise. There was no association between ERP and echocardiographic findings of left ventricular remodeling and geometric pattern.Conclusion:ERP is a frequent finding among teenage athletes. However, frequency varies by sports type, being more common in those training with combined exercise. It is not associated with structural echocardiographic alterations and is primarily seen as an electrophysiological change.

Early Repolarization in Pediatric Athletes: A Dynamic Electrocardiographic Pattern With Benign Prognosis

BackgroundEarly repolarization pattern (ERP) is considered a common training‐related and benign ECG finding in young adult athletes. Few data exist on ERP in the pediatric athletes population. Therefore, we aimed to evaluate the ERP prevalence, characteristics, and prognosis in pediatric athletes aged ≤16 years.Methods and ResultsEight‐hundred eighty‐six consecutive pediatric athletes engaged in 17 different sports (mean age, 11.7±2.5 years; 7–16 years) were enrolled and prospectively evaluated with medical history, physical examination, resting and exercise ECGs, and transthoracic echocardiography during their preparticipation screening. Known cardiovascular diseases associated with sudden cardiac death was considered exclusion criteria. Athletes were followed up yearly for 4 years. The prevalence of ERP was 117 (13.2%), equally distributed in both sexes (P=0.072), irrespectively of body mass index and classification of sports. The most common ERP localizations were inferolateral and inferior leads (53.8% and 27.3%, respectively). Notching J‐point morphology was the most prevalent (70%), and rapidly ascending ST elevation (96%) was the most common ST‐segment morphology. Athletes with ERP were older (P<0.001) had lower rest and recovery heart rates (P<0.001), increased precordial and limb R‐wave voltages (P<0.001), increased R/S Sokolow index (P<0.001), and longer PR interval (P=0.006) in comparison with the athletes without ERP. Neither major cardiovascular nor arrhythmic events, nor sudden cardiac death were recorded over a median follow‐up of 4.2 years. One hundred seventeen (80.3%) athletes with ERP exhibited a persistent ERP. ERP localization and J‐point morphology changed during follow‐up in 11 (11.7%) and 17 (18%) of athletes, respectively.ConclusionsERP is common in pediatric athletes. It was mostly located in the inferolateral leads and associated with concave ascending ST segment with other training‐related ECG changes. The lack of either sudden cardiac death or cardiomyopathies linked to sudden cardiac death over follow‐up suggests that in pediatric athletes, ERP may be considered a benign training‐related ECG phenomenon with a potential dynamic pattern.

Canine Myocytes Represent a Good Model for Human Ventricular Cells Regarding Their Electrophysiological Properties.

Due to the limited availability of healthy human ventricular tissues, the most suitable animal model has to be applied for electrophysiological and pharmacological studies. This can be best identified by studying the properties of ion currents shaping the action potential in the frequently used laboratory animals, such as dogs, rabbits, guinea pigs, or rats, and comparing them to those of human cardiomyocytes. The authors of this article with the experience of three decades of electrophysiological studies, performed in mammalian and human ventricular tissues and isolated cardiomyocytes, summarize their results obtained regarding the major canine and human cardiac ion currents. Accordingly, L-type Ca2+ current (ICa), late Na+ current (INa-late), rapid and slow components of the delayed rectifier K+ current (IKr and IKs, respectively), inward rectifier K+ current (IK1), transient outward K+ current (Ito1), and Na+/Ca2+ exchange current (INCX) were characterized and compared. Importantly, many of these measurements were performed using the action potential voltage clamp technique allowing for visualization of the actual current profiles flowing during the ventricular action potential. Densities and shapes of these ion currents, as well as the action potential configuration, were similar in human and canine ventricular cells, except for the density of IK1 and the recovery kinetics of Ito. IK1 displayed a largely four-fold larger density in canine than human myocytes, and Ito recovery from inactivation displayed a somewhat different time course in the two species. On the basis of these results, it is concluded that canine ventricular cells represent a reasonably good model for human myocytes for electrophysiological studies, however, it must be borne in mind that due to their stronger IK1, the repolarization reserve is more pronounced in canine cells, and moderate differences in the frequency-dependent repolarization patterns can also be anticipated.

Evaluation of the Seattle and International Criteria in elite Nigerian athletes

BackgroundThe Seattle Criteria (SC) and International Criteria (IC) were both developed for cardiovascular pre-participation screening in young athletes. Neither set of Criteria has been systematically evaluated in high level indigenous black African athletes. Objectives(1) To determine the pattern of ECG findings in athletes of the University of Port Harcourt, Nigeria; (2) To determine the predictors of altered repolarization in these athletes; and (3) To evaluate the diagnostic performance of the SC and IC in these athletes. Methods77 athletes (42 males, 35 females) without any known cardiovascular disease were recruited alongside 78 similarly healthy non-athletic controls (44 males, 34 females). The two groups were matched for age, sex, and body mass index. Clinical assessment was according to the Lausanne Recommendations. All subjects underwent electrocardiography and echocardiography. Analysis with the IC was retrospective. ResultsThe most common physiological finding in the athletes was sinus bradycardia (n = 37; 48.1%). Early repolarization pattern, ERP (n = 27, 35.1% with SC; n = 42, 54.5% with IC), and dome-shaped ST-segment elevation with T-wave inversion (DSSTWI) in leads V1–4 (n = 21, 29.3% with both criteria), were also prevalent. Compared to controls, only male sex (adjusted odds ratio 2.89, 1.05 to 7.97, p = .040 with SC; OR 2.57, 1.19 to 5.53, p = .016 with IC) and ECG LVH (OR 2.82, 1.18 to 6.75, p = .020 with SC alone) independently predicted ERP, while athletic status (OR 4.76, 1.66 to 13.68, p = .004 with both criteria) alone had a significant multivariate association with DSSTWI. Three athletes (3.9%) had abnormal ECGs while two (2.6%) had major echocardiographic abnormalities. The sensitivity, specificity and accuracy of the SC for structural cardiac disease in the athletes were 50.0% (1.3 to 98.7), 97.3% (90.7 to 99.7) and 96.1% (89.0 to 99.2) respectively. The respective figures for the IC were 50.0% (1.3 to 98.7), 98.7% (92.8 to 100) and 97.4% (90.9 to 99.7). ConclusionBoth criteria showed high accuracy in this Black African cohort with a high frequency of electrocardiographic repolarization changes. While ERP seems to be primarily related to black ethnicity, DSSTWI appears to be a bona fide marker of Athlete's Heart in blacks.

J wave syndrome: Benign or malignant?

J wave syndrome is an electrical disease of the heart due to pathologic early repolarization. It encompasses a clinical spectrum from aborted sudden cardiac death due to ventricular arrhythmia (VA) usually in young affected patients to self-terminating ventricular ectopies, and finally, asymptomatic relatives of probands detected during electrocardiography acquisition (early repolarization pattern). This syndrome consists of 2 phenotypes, early repolarization and Brugada syndrome. Herein, we first describe 2 patients with early repolarization and Brugada syndrome, then, discuss their definition, epidemiology, genetics, cellular mechanism, diagnosis, risk stratification, and finally, therapeutic challenges and options one by one in detail.

The β-angle can help guide clinical decisions in the diagnostic work-up of patients suspected of Brugada syndrome: a validation study of the β-angle in determining the outcome of a sodium channel provocation test.

AimsIn patients with Brugada syndrome (BrS) but without spontaneous Type-1 electrocardiogram, several electrocardiographic characteristics have been studied, including the β-angle. Previous studies suggested that the β-angle might be useful in distinguishing BrS-patients from patients with only suggestive repolarization patterns without performing sodium channel blocker provocation testing. In this study, we aimed to determine the diagnostic value of the β-angle in patients suspected of BrS.Methods and resultsA large cohort (n = 1430) of consecutive patients who underwent provocation testing was evaluated. β-angles were measured in leads V1, V2, and their corresponding positions over the second and third intercostal space. Receiver-operating characteristic curves were constructed and the diagnostic accuracy of previously reported β-angle cut-offs were calculated and evaluated. The importance of the β-angle for predicting the provocation test outcome was determined using a prediction model constructed with logistic regression. The optimum β-angle cut-off in our cohort for ruling out a positive provocation test was 15°; sensitivities were 80–98% and negative predictive values were 79–96% among the right precordial leads. Previously reported β-angle cut-offs performed less well, indicated by lower Youden indices. In the optimism-corrected prediction model [C-statistic: 0.78 (95% CI: 0.75–0.81)], the β-angle had large value (Z-score: 2.1–10.3) and aided construction of a nomogram to predict test outcome.ConclusionTo predict the outcome of provocation testing for BrS, the β-angle alone does not demonstrate strong diagnostic characteristics. However, the β-angle is an important variable to predict provocation test outcome and thus has added value.

Early repolarization pattern in adult females with eating disorders.

IntroductionThe risk of cardiovascular death is increased in patients with eating disorders (ED), but the background for this is unknown. Early repolarization pattern (ERP) on the electrocardiogram (ECG) has been associated with increased risk of sudden cardiac death.MethodsWe investigated the prevalence of ERP in 233 female patients with anorexia nervosa (AN) and bulimia nervosa (BN) (age 18–35 years) compared with 123 healthy female controls.ResultsEarly repolarization pattern was present in 52 (22%) of ED patients (16 (15%) AN patients and 36 (29%) BN patients) and 17 (14%) of healthy controls. When adjusting for age, BMI, heart rate, use of selective serotonin reuptake inhibitors (SSRI), and potassium level, the odds ratio (OR) for ERP was 2.1 (95% CI 1.1–4.2, p = .03). There was an increased prevalence of inferolateral ERP in patients with ED compared with healthy controls (OR = 4.3, 95% CI 1.7–11.3, p = .003) as well as ERP with a downward/horizontal sloping ST segment (OR = 3.1, 95% CI 1.3–7.6, p = .01). Additionally, J‐point elevation >0.2 mV was more prevalent in patients with ED (OR = 3.3, 95% CI 1.1–9.7, p = .03).ConclusionThe prevalence of ERP was increased in patients with ED compared with healthy controls. This finding may provide a possible explanation for the increased cardiovascular mortality in ED patients.

The diagnostic value of 2D-speckle tracking echocardiography for identifying subclinical ventricular dysfunction in subjects with early repolarization pattern.

Early repolarization pattern (ERP) can exist a silent substrate for arrhytmic events in accordance with the previous studies which have shown there has been evidence of morphological changes in left ventricle (LV) in ERP subjects. Despite structural changes in ERP subjects, it has not exactly known whether a change in LV functional parameters occur in ERP. The aim of our study was to investigate LV functional parameters in ERP athletes evaluated by 2D- speckle tracking echocardiography (2D-STE). In this study, athletes with ERP (n=50) and athletes without ERP (n=50) were recruited between April 2018 and September 2018. For each case, 2D- TTE and 2D- STE evaluation were performed by the same cardiologist. Left ventricle mean global longitudinal strain (GLS) (P<.001) and GLS at all apical chamber views (P<.001), longitudinal peak systolic strain rate (SRS) at A3C (P: .011), early diastolic strain rate (SRE) at A3C (P<.001) and late diastolic strain rate (SRA) at A3C (P: .034) in the ERP athletes were significantly lower than those in the athletes without ERP. LV basal segment circumferential SRS (P: .002) and SRE (P: .006) were significantly lower in ERP athletes compared to athletes without ERP. LV mechanical dispersion was significantly higher in ERP athletes compared to athletes without ERP (P<.001). Our study suggests ERP can be more associated with impaired LV longitudinal function than circumferential function. In addition, both LV inferolateral region and basal segment can be more affected functionally in ERP athletes.

Worldwide prevalence of early repolarization pattern in general population and physically active individuals: A meta-analysis.

Background:The early repolarization pattern (ERP) has recently been associated with cardiac events such as ventricular arrhythmias and sudden cardiac death. However, estimates of the prevalence of ERP vary widely, especially between the general population and physically active individuals. We performed this systematic review and meta-analysis to quantitatively evaluate the worldwide prevalence of ERP in the general population and physically active individuals.Methods:We thoroughly searched the PubMed, EMBASE, Web of science, the Cochrane Library, and Scopus databases for relevant studies published until December 20, 2020. Studies in which prevalence was presented or could be estimated from eligible data were included. The pooled prevalence was analyzed using a random-effect model.Results:Finally, we included 29 studies (182,135 subjects) in the general population and 14 studies (8087 subjects) in the physically active individuals. The worldwide pooled prevalence of ERP in the general population was 11.6% (95% confidence interval [CI]: 10.0%–13.3%). The incidence of ERP was 17.0% and 6.2% in men and women, respectively. The prevalence was 20.9% in blacks, 13.4% in Asians, and 10.1% in Caucasians. Additionally, the prevalence of ERP in physically active individuals was 33.9% (95% CI: 25.3%–42.6%).Conclusion:A significant difference in the worldwide prevalence of ERP is revealed in this study. The ERP is highly prevalent in men, blacks, and physically active individuals.

His resynchronization therapy produces more physiological ventricular repolarisation compared with biventricular pacing

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): British Heart Foundation BACKGROUND Biventricular pacing (BVP) is known to shorten activation time in patients with heart failure and left bundle branch block (LBBB) but its effects on repolarisation are not well studied. His bundle pacing (HBP) can correct LBBB to deliver cardiac resynchronization therapy (HBP-CRT), producing more physiological ventricular activation time and pattern than BVP. It is not known whether this translates to more physiological repolarisation, and if so whether the effect is mediated through its effects on activation. PURPOSE We measured the effects of HBP-CRT and BVP on left ventricular repolarisation using non-invasive epicardial mapping (ECGI). METHODS Patients were recruited in two groups. 1) Patients scheduled for clinically indicated BVP procedures for heart failure with LBBB, 2) Individuals with narrow QRS, normal ventricular function and intact conduction systems. Using non-invasive electrocardiographic imaging, we identified patients with LBBB in whom HBP shortened ECGI-derived left ventricular (LV) activation time by &amp;gt;10ms. We compared the effects of HBP and BVP on ECGI-derived dispersion of LV repolarisation times and activation-recovery intervals (a surrogate for action potential duration). RESULTS 21 patients in whom HBP shortened LV activation time by &amp;gt;10ms and an equal number of individuals with narrow intrinsic QRS were recruited. LV repolarisation dispersion was reduced by HBP-CRT (-42.0 ms, 95% confidence interval (CI): -52.3 to -31.7 ms, p &amp;lt;0.001) but not by BVP (11.9 ms, 95% CI: -6.24 to 30.1 ms, p = 0.182). The mean within-patient change in LV repolarisation dispersion from BVP to HBP-CRT was -56.5 ms (95% CI: -70.5 to -42.5 ms, p &amp;lt; 0.001). LV repolarisation dispersion with HBP-CRT was not different from individuals with narrow intrinsic QRS (2.75 ms, 95% CI: -16.2 to 21.7 ms, p = 0.981). The magnitude of reduction in LV repolarisation dispersion with HBP-CRT from intrinsic LBBB appeared similar to the magnitude of LV activation time shortening (-54.9 ms, 95% CI: -68.2 to -41.6 ms, p &amp;lt; 0.001). However, LV activation-recovery interval dispersion was also reduced by HBP-CRT (-44.3 ms, 95% CI: -69.2 to -19.3 ms, p &amp;lt; 0.001). Repolarisation mapping demonstrated normalisation of repolarisation pattern by HBP-CRT. CONCLUSIONS HBP-CRT can normalise repolarisation dispersion, producing more physiological repolarisation compared with BVP, which does not resolve the repolarisation abnormality of LBBB. HBP-CRT improves repolarisation through both activation resynchronization and modulation of action-potential duration. If these acute results translate to longer term outcomes, HBP-CRT may reduce the risk of ventricular arrhythmias in heart failure with LBBB to a greater extent than BVP. Abstract Figure. Epicardial Repolarisation Maps

Early Repolarization Pattern and Idiopatic Sustained Monomorphic Ventricular Tachycardia: an Infrequent Combination

Malignant early repolarization as cause of sudden death has taken on great importance in recent years. It has been described as an entity capable of producing ventricular arrhythmic events, causing from episodes of syncope to sudden cardiac death. Ventricular fibrillation is the typical arrhythmia in these patients, with no clear relationship to date with idiopathic monomorphic ventricular tachycardia. Electrocardiographic markers related to the development of arrhythmic events in early repolarization syndrome have been described. They seem not only related to the development of ventricular fibrillation, but also to sustained monomorphic ventricular tachycardia, as is the case described in the article.

Electrocardiogram Changes in the Spectrum of TTNtv Dilated Cardiomyopathy: Accuracy and Predictive Value of a New Index for LV-Changes Identification

Truncating TTN variants (TTNtv) are the main cause of dilated cardiomyopathy (DCM). The dynamic nature of this entity has previously been described. Based on own empirical observations and previous evidences, this study assessed repolarisation patterns and the possible association with morphological and functional status of TTNtv-DCM patients. Electrocardiograms (ECGs) of index patients with TTNtv-DCM and their relatives were included and matched in time with an echocardiogram. All individuals were classified into five phenotype groups: 1) Reduced left ventricular ejection fraction (LVEF <50%); 2) Recovered LVEF: at least 10% increase and LVEF >30% after optimal medical treatment; 3) Borderline phenotype (mildly enlarged ventricle and/or hyper-trabeculation); 4) Genotype positive, phenotype negative; and 5) Non-carriers. All electrocardiograms were evaluated by two blinded observers in qualitative and quantitative terms [T index (mm)=Σ T-wave amplitude (V5, V6, II, aVF)] and these data were compared with demographic and clinical information. The Δ T-index was calculated in those individuals with more than one electrocardiogram. Seventy-eight (78) electrocardiograms were included (46% female, mean age 50 years). T-index and prevalence of an abnormal T-wave had significantly different results among the groups (p<0.0001). Age and haemodynamic factors were shown to be ECG-modifiers, especially in phenotype-negative patients. T-index enabled individuals with reduced LVEF (<2.5) to be identified and to differentiate patients with favourable and unfavourable responses to treatment (Δ T index >3.5 and ≤2, respectively). Repolarisation changes enabled characterisation of the spectrum of TTNtv-DCM. The T-index identified potential carriers and patients with the worst profiles of the spectrum of the disease.

Standard ECG in Brugada Syndrome as a Marker of Prognosis: From Risk Stratification to Pathophysiological Insights.

BackgroundThe 12‐lead ECG plays a key role in the diagnosis of Brugada syndrome (BrS). Since the spontaneous type 1 ECG pattern was first described, several other ECG signs have been linked to arrhythmic risk, but results are conflicting.Methods and ResultsWe performed a systematic review to clarify the associations of these specific ECG signs with the risk of syncope, sudden death, or equivalents in patients with BrS. The literature search identified 29 eligible articles comprising overall 5731 patients. The ECG findings associated with an incremental risk of syncope, sudden death, or equivalents (hazard ratio ranging from 1.1–39) were the following: localization of type 1 Brugada pattern (in V2 and peripheral leads), first‐degree atrioventricular block, atrial fibrillation, fragmented QRS, QRS duration >120 ms, R wave in lead aVR, S wave in L1 (≥40 ms, amplitude ≥0.1 mV, area ≥1 mm2), early repolarization pattern in inferolateral leads, ST‐segment depression, T‐wave alternans, dispersion of repolarization, and Tzou criteria.ConclusionsAt least 12 features of standard ECG are associated with a higher risk of sudden death in BrS. A multiparametric risk assessment approach based on ECG parameters associated with clinical and genetic findings could help improve current risk stratification scores of patients with BrS and warrants further investigation.RegistrationURL: https://www.crd.york.ac.uk/prospero/. Unique identifier: CRD42019123794.

Pediatric athletes' ECG and diagnostic performance of contemporary ECG interpretation criteria

BackgroundElectrocardiographic (ECG) pre-participation screening(PPS) can prevent sudden cardiac death(SCD) but the Interpretation of the athlete's ECG is based on specific criteria addressed for adult athletes while few data exist about the pediatric athlete's ECG.We aimed to assess the features of pediatric athletes' ECG and compared the diagnostic performance of 2017 International ECG recommendation, 2010 European Society of Cardiology recommendation and 2013-Seattle criteria in detecting clinical conditions at risk of SCD. Methods886 consecutive pediatric athletes (mean age 11.7 ± 2.5 years; 7–16-years) were enrolled and prospectively evaluated with medical history, physical examination, resting and exercise ECG and transthoracic echocardiography during their PPS. ResultsThe most common physiological ECG patterns in pediatric athletes were isolated left ventricular hypertrophy criteria (26.9%), juvenile T-wave pattern (22%) and early repolarization pattern (13.2%). The most frequent borderline abnormalities were left axis deviation (1.8%) and right axis deviation (0.9%) while T-wave inversion (0.8%) especially located in inferior leads (0.7%) was the most prevalent abnormal findings. Seven athletes (0.79%) were diagnosed with a condition related to SCD. Compared to Seattle and ESC, the International improved ECG specificity (International = 98% ESC = 64% Seattle = 95%) with lower sensitivity (ESC and Seattle 86%vs International 57%). The false-positive rate decreases from 36% of ESC to 2.2% of International but the latter showed a higher false-negative rate(0.34%). ConclusionPediatric athletes like the adult counterpart exhibit a high prevalence of ECG abnormalities mostly representing training-related ECG adaptation. The International criteria showed a lower false-positive rate but at the cost of loss of sensitivity.

Gender-affirming hormone treatment causes changes in gender phenotype in a 12-lead electrocardiogram

Men and women have specific patterns in an electrocardiogram (ECG) differentiated by J-point elevation and ST-segment angle. Although gender-affirming hormone treatment is one of the treatments for gender dysphoria, its influence on an ECG has not been clarified yet. The purpose of this study was to investigate ECG changes induced by gender-affirming hormone treatment. The study population consisted of 29 transgender males and 8 transgender females and 37 age- and sex-matched cisgender females and males. Male pattern was defined as J-point elevation > 0.1 mV and ST-segment angle > 20° in precordial leads. In the comparison between 29 transgender males and cisgender females, the prevalence of the male pattern (89.7% vs 6.9%; P < .001), prevalence of the early repolarization pattern (51.7% vs 17.2%; P = .01), J-point elevation (leads V1-V6), T-wave amplitudes (leads V1-V6), QRS amplitudes (leads II, III, V1-V6), and P-wave amplitudes (leads V1-V3) were significantly higher in transgender males. The prevalence of the male pattern was lower in transgender females than in cisgender males (25.0% vs 87.5%; P= .04). In the analysis of transgender males for whom ECGs were available before and after gender-affirming hormone treatment (n = 13), J-point elevation and T-wave amplitudes significantly increased after gender-affirming hormone treatment, leading to a higher prevalence of the male pattern (23.1% vs 92.3%; P < .001). The prevalence of the early repolarization pattern and QRS amplitudes also significantly increased after the treatment, but the augmentation of P-wave amplitudes was modest. Gender-affirming hormone treatment for gender dysphoria is accompanied by a change in ECG phenotype toward affirming gender, in which change in androgen level may be involved.

Signal averaged ECG in patients with early repolarization.

BackgroundEarly repolarization (ER) pattern is diagnosed when the J‐point is elevated on the patient's electrocardiogram. The aim of this study was to evaluate signal‐averaged electrocardiography (SAECG) in patients with ER pattern.MethodsSubjects were divided into three groups: 1‐patients with normal ECG pattern (control group); 2‐patients with J‐point elevation in the inferior leads; and 3‐patients with J‐point elevation in non‐inferior leads.ResultsThe mean filtered QRS duration in groups with J‐point elevation in inferior leads and non‐inferior leads and in the control, was 86.4 ± 23.4 msec, 84.8 ± 26.6 msec, and 85.8 ± 24.8 msec, respectively, indicating no significant difference across the three groups. The mean duration of terminal QRS < 40µV was 21.2 ± 4.2 msec, 22.8 ± 4.6 msec, and 23.1 ± 4.5 msec in the mentioned groups, respectively, without a significant difference between the groups. Additionally, the mean root‐mean‐square voltage of terminal 40 msec was 34.5 ± 8.3 µV, 35.3 ± 8.6µV, and 35.7 ± 9.2 µV in patients with increased J‐point in inferior leads, non‐inferior leads, and the control group, respectively, showing no difference between the groups.ConclusionIn conclusion, we found that parameters in SAECG did not have any significant difference between patients with ER pattern and healthy individuals. Moreover, we concluded that SAECG cannot distinguish the patients with elevated J‐point in inferior leads from non‐inferior leads. Overall, SAECG does not appear to be a reliable diagnostic tool for the assessment of ER pattern.

Day-to-Day Variation of Early Repolarization Pattern Predicts Life-Threatening Arrhythmias in Patients With Brugada Syndrome.

We assessed the relationship between day-to-day variation of the early repolarization (ER) pattern and ventricular tachyarrhythmia (VTA) events in Brugada syndrome (BrS) patients because the clinical implications are unclear.Methods and Results:This retrospective study consisted of 41 patients with BrS who underwent implantable cardioverter-defibrillator (ICD) implantation. BrS was diagnosed by a spontaneous or drug-induced type 1 ECG without structural heart disease. Day-to-day variation of the ER pattern was defined as temporal change in the J-point (≥0.1 mV) on ECG. VTA events were detected via ICD interrogation: 15 patients experienced VTA events during 124±62 months' observation. Day-to-day variation of the ER pattern was positive in 7 patients (17%). In the multivariate Cox proportional hazards model, day-to-day variation of a positive ER pattern (hazard ratio [HR]: 3.475, 95% confidence interval [CI]: 1.105-10.414, P=0.034) and documented history of VTA (HR: 4.802, 95% CI: 1.547-17.995, P=0.006) were independent predictors of VTA events. In patients with electrical storm (ES: n=9), day-to-day variation of the ER pattern was positive in 5 patients (56%). ES events were more frequently observed in patients with a positive day-to-day variation of ER pattern than in those without (P<0.05). The incidence of day-to-day variation of the ER pattern was higher in patients with arrhythmic events of VTA and/or ES among BrS patients with ICD.

Electric Field-Based Dense Spatial Analysis of Unipolar Electrograms to Map Regional Activation-Repolarization Intervals

Objective: We wanted to develop a new method for processing dense spatially sampled unipolar electrograms, that yields physiological spatial distributions in activation-repolarization intervals.Background: Spatial heterogeneity in repolarization plays an important role in genesis and sustainment of cardiac arrhythmias. Reliable determination of repolarization times at high resolution on electrograms remains a difficult task. Methods: The new method describes the electrical activity on the heart's surface in terms of a physical electric field (E-field). Activation and repolarization times are calculated using an amplitude weighted average on QRS and T-waves. Activation-recovery intervals (ARI) obtained with this E-field method were validated against action potential durations (APD90) from monophasic action potential measurements. Relevance of the method was shown by calculating dense spatial distributions of beat-to-beat variability of repolarization (BVR) in myocardial infarction (MI).Results: E-field waveforms were more spatially homogeneous than the unipolar electrograms. The ARI strongly correlated with the APD90 (r2=0.94; p<0.001). Continuous activation and repolarization patterns were obtained, and the method removes non-physiological sharp spatial gradients obtained by currently adopted methods. Spatial BVR analysis revealed an increase in maximum BVR, spatial variance of BVR and spatial gradient of BVR in the border zone versus remote region of MI (all p<0.01). All BVR values were in pathophysiological range as described in other studies.Conclusion: The E-field method allows for a reliable determination of activation and repolarization times over the whole left ventricle. The new methodology confirmed that the border zone of myocardial infarction is a region with patches of increased variability of repolarization.

J waves in arrhythmogenic cardiomyopathy versus primary electrical disease

In case reports early repolarization (ER) is associated with arrhythmogenic cardiomyopathy. In smaller case analyses ER is a discussable risk marker. Furthermore, the association with inversions of right precordial T-waves should be analysed. Method: In a cohort of 360 patients with typical ESC/ISFC criteria of arrhythmogenic cardiomyopathy (176 males, mean age 47.3 +/- 13.7 years) the presentation with ER and the risk assessment for sudden cardiac arrest was analyzed. Results: A total of 113 cases (31%) with inferior (22%), inferolateral (3%), and lateral (6%) notching or slurring was presented as typical signs of early repolarization syndrome. Together with the results of ajmaline challenge it is in close relation with the number of right precodial T-wave inversions. Early repolarization does not identify patients at risk for sudden cardiac arrest. In single cases the risk was increased in cases with ST elevation in early repolarization pattern as primary electrical disease. Conclusions: The number of early repolarization pattern in typical arrhythmogenic cardiomyopathy is increased and relates to the number of right precordial T-wave inversions of 55% in this cohort. Early repolarization is generally not a risk marker, but in single cases overlapping primary electrical disease can be documented.