Background: Early electrocardiograph predates electronic amplification and therefore required innovative and highly sensitive instrumentation. Willem Einthoven's introduction of the string galvanometer in 1903 enabled recording of clinically useful electrocardiograms and established electrocardiography as a diagnostic method.
Objectives: To describe the provenance and technical features of a uniquely complete string-galvanometer system preserved in Lund, Sweden, and to review early commercial production and surviving string galvanometers manufactured before 1910.
Methods: The Lund electrocardiograph was examined and compared with historical photographs, documentation from Einthoven's laboratory, archival sources, and contemporary literature. Museum and institutional collections as well as manufacturers' records were surveyed for surviving old instruments.
Results: The Lund string galvanometer electrocardiograph, constructed in 1909 from Einthoven's original drawings, retains its optical, magnetic coil system, cooling, and recording components and closely matches documented laboratory models. Only two companies produced string galvanometers commercially by then: Professor Max Th. Edelmann's Physikalisch-mechanisches Institut (Munich, Germany) and the Cambridge Scientific Instrument Company (Cambridge, England). Cambridge sold only 14 devices before 1910, and no complete instrument is known to have survived; Edelmann's production is poorly documented, with only few examples preserved.
Conclusions: Intact electrocardiographs from the earliest period of electrocardiography are extremely rare. The Lund instrument represents one of the best-preserved surviving complete devices and underscores the importance of documenting and conserving early biomedical technology.
{"title":"Electrocardiographs before 1910: Manufacturers and surviving instruments","authors":"Olle Pahlm MD PhD , Bengt Uvelius MD PhD , Anders Widell MD PhD","doi":"10.1016/j.jelectrocard.2025.154178","DOIUrl":"10.1016/j.jelectrocard.2025.154178","url":null,"abstract":"<div><div>Background: Early electrocardiograph predates electronic amplification and therefore required innovative and highly sensitive instrumentation. Willem Einthoven's introduction of the string galvanometer in 1903 enabled recording of clinically useful electrocardiograms and established electrocardiography as a diagnostic method.</div><div>Objectives: To describe the provenance and technical features of a uniquely complete string-galvanometer system preserved in Lund, Sweden, and to review early commercial production and surviving string galvanometers manufactured before 1910.</div><div>Methods: The Lund electrocardiograph was examined and compared with historical photographs, documentation from Einthoven's laboratory, archival sources, and contemporary literature. Museum and institutional collections as well as manufacturers' records were surveyed for surviving old instruments.</div><div>Results: The Lund string galvanometer electrocardiograph, constructed in 1909 from Einthoven's original drawings, retains its optical, magnetic coil system, cooling, and recording components and closely matches documented laboratory models. Only two companies produced string galvanometers commercially by then: Professor Max Th. Edelmann's Physikalisch-mechanisches Institut (Munich, Germany) and the Cambridge Scientific Instrument Company (Cambridge, England). Cambridge sold only 14 devices before 1910, and no complete instrument is known to have survived; Edelmann's production is poorly documented, with only few examples preserved.</div><div>Conclusions: Intact electrocardiographs from the earliest period of electrocardiography are extremely rare. The Lund instrument represents one of the best-preserved surviving complete devices and underscores the importance of documenting and conserving early biomedical technology.</div></div>","PeriodicalId":15606,"journal":{"name":"Journal of electrocardiology","volume":"94 ","pages":"Article 154178"},"PeriodicalIF":1.2,"publicationDate":"2025-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145810046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In patients with acute anterior myocardial infarction (MI), abnormalities in conduction intervals and waveform amplitudes observed on admission electrocardiograms may reflect the extent of myocardial damage. However, their prognostic significance following percutaneous coronary intervention (PCI) remains incompletely understood.
Methods
We enrolled consecutive patients undergoing emergent PCI for acute anterior MI and performed hierarchical cluster analysis based on P-wave duration (Pd), P-wave amplitude (PWA), PQ interval, QRS duration, and corrected QT interval (QTc). The primary outcome was a composite of heart failure hospitalization and all-cause mortality after PCI, which was compared across the identified phenogroups.
Results
A total of 426 patients were included. Optimal cut-off values for Pd, PWA (leads II, V2, and V6), PQ interval, QRS duration, and QTc in predicting the composite outcome were determined via receiver operating characteristic (ROC) curve analysis. Hierarchical clustering identified four distinct electrocardiographic phenotypes: Phenotype 1 (“Normal morphology”), Phenotype 2 (“Low PWA and wide QRS”), Phenotype 3 (“Prolonged Pd/PQ, low PWA, wide QRS, and prolonged QTc”), and Phenotype 4 (“Prolonged Pd/PQ”). Kaplan–Meier analysis revealed that Phenotype 3 was significantly associated with the highest risk of the composite outcome. This phenotype also exhibited the highest prevalence of atrial fibrillation, along with more frequent renal dysfunction and multivessel coronary artery disease, suggesting the coexistence of pre-existing atrial dysfunction and ventricular electrical–structural abnormalities possibly related to ischemia.
Conclusions
In patients with acute anterior MI undergoing PCI, electrocardiographic markers indicative of atrial dysfunction, particularly abnormal P-wave morphology, were significantly associated with adverse clinical outcomes.
{"title":"Prognostic value of electrocardiographic phenotypes based on conduction intervals and waveform amplitudes in acute anterior myocardial infarction","authors":"Masamichi Yano MD, PhD , Yasuyuki Egami MD , Noriyuki Kobayashi MD , Ayako Sugino MD , Masaru Abe MD , Mizuki Ohsuga MD , Hiroaki Nohara MD , Shodai Kawanami MD , Kohei Ukita MD , Akito Kawamura MD , Koji Yasumoto MD , Naotaka Okamoto MD , Yasuharu Matsunaga-Lee MD , Masami Nishino MD, PhD","doi":"10.1016/j.jelectrocard.2025.154175","DOIUrl":"10.1016/j.jelectrocard.2025.154175","url":null,"abstract":"<div><h3>Background</h3><div>In patients with acute anterior myocardial infarction (MI), abnormalities in conduction intervals and waveform amplitudes observed on admission electrocardiograms may reflect the extent of myocardial damage. However, their prognostic significance following percutaneous coronary intervention (PCI) remains incompletely understood.</div></div><div><h3>Methods</h3><div>We enrolled consecutive patients undergoing emergent PCI for acute anterior MI and performed hierarchical cluster analysis based on P-wave duration (Pd), P-wave amplitude (PWA), PQ interval, QRS duration, and corrected QT interval (QTc). The primary outcome was a composite of heart failure hospitalization and all-cause mortality after PCI, which was compared across the identified phenogroups.</div></div><div><h3>Results</h3><div>A total of 426 patients were included. Optimal cut-off values for Pd, PWA (leads II, V2, and V6), PQ interval, QRS duration, and QTc in predicting the composite outcome were determined via receiver operating characteristic (ROC) curve analysis. Hierarchical clustering identified four distinct electrocardiographic phenotypes: Phenotype 1 (“Normal morphology”), Phenotype 2 (“Low PWA and wide QRS”), Phenotype 3 (“Prolonged Pd/PQ, low PWA, wide QRS, and prolonged QTc”), and Phenotype 4 (“Prolonged Pd/PQ”). Kaplan–Meier analysis revealed that Phenotype 3 was significantly associated with the highest risk of the composite outcome. This phenotype also exhibited the highest prevalence of atrial fibrillation, along with more frequent renal dysfunction and multivessel coronary artery disease, suggesting the coexistence of pre-existing atrial dysfunction and ventricular electrical–structural abnormalities possibly related to ischemia.</div></div><div><h3>Conclusions</h3><div>In patients with acute anterior MI undergoing PCI, electrocardiographic markers indicative of atrial dysfunction, particularly abnormal P-wave morphology, were significantly associated with adverse clinical outcomes.</div></div>","PeriodicalId":15606,"journal":{"name":"Journal of electrocardiology","volume":"94 ","pages":"Article 154175"},"PeriodicalIF":1.2,"publicationDate":"2025-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145819368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-17DOI: 10.1016/j.jelectrocard.2025.154177
Hedieh Alimi , Ali Tajik , Mohsen Moohebati , Alireza Heidari-Bakavoli , Naghmeh Layegh Khavidaki , Alireza Ghajari , Zahra Ghazizadeh , Habibollah Esmaily , Gordon A. Ferns , Sara Saffar Soflaei , Majid Ghayour-Mobarhan
Background and objective
P wave indices obtained from the electrocardiogram (ECG) serve as indicators of atrial conduction. P-wave duration (PWD) has been associated with various pathological conditions. The relationship between this factor and cardiovascular mortality remains insufficiently explored. To ascertain the association of PWD and cardiovascular and all-cause mortality in the MASHAD cohort study population.
Method
Participants were recruited from the Mashhad Stroke and Heart Atherosclerotic Disorder (MASHAD) cohort study. Participants' demographic information were recorded by checklist. Additionally, a comprehensive medical history was collected to identify cardiovascular risk factors, and history of pre-existing cardiovascular disease (CVD). A 12‑lead electrocardiogram (ECG) was obtained from the participants and they were subsequently categorized into two groups based on their PWD (≥ 120 msec and < 120 msec). All participants were followed for a minimum of 10 years for mortality assessment. We employed Cox regression to evaluate the relationship between PWD and cardiovascular and all-cause mortality. In order to evaluate the incremental predictive value of P wave duration, we calculated the net reclassification improvement (NRI) and integrated discrimination improvement (IDI) at 10-year follow-up timepoint. Subsequently, we developed Kaplan-Meier plots, time-dependent ROC curves, and restricted cubic splines (RCS) to thoroughly evaluate the association between PWD and cardiovascular mortality. Subgroup analysis was conducted to evaluate the impact of PWD across various distinct groups.
Results
A total of 8885 participants were enrolled in the study. Prolonged PWD was associated with higher all-cause, cardiovascular mortality in unadjusted model. After controlling for covariates, PWD remained significantly associated with all-cause and cardiovascular mortality in continuous form of it. However, PWD in categorical form did not show significant association with cardiovascular mortality. The addition of P wave duration to the conventional model did not provide statistically significant improvement in risk reclassification or discrimination for either all-cause or cardiovascular mortality. The RCS models indicated that the PWD displayed a positive linear correlation with the risk of all-cause mortality across all models. The time-dependent ROC curve demonstrated favorable predictive performance for the adjusted models at both the 5-year and 10-year timepoints. The subgroup analysis revealed no interaction among the subgroups in our statistically significant multivariable models (all p for interaction >0.05).
Conclusion
Continuous P-wave duration predicted all-cause and cardiovascular mortality, whereas the conventional 120 ms cut-off showed limited prognostic utility.
{"title":"Association of P-wave duration with all-cause and cardiovascular mortality in MASHAD cohort study","authors":"Hedieh Alimi , Ali Tajik , Mohsen Moohebati , Alireza Heidari-Bakavoli , Naghmeh Layegh Khavidaki , Alireza Ghajari , Zahra Ghazizadeh , Habibollah Esmaily , Gordon A. Ferns , Sara Saffar Soflaei , Majid Ghayour-Mobarhan","doi":"10.1016/j.jelectrocard.2025.154177","DOIUrl":"10.1016/j.jelectrocard.2025.154177","url":null,"abstract":"<div><h3>Background and objective</h3><div>P wave indices obtained from the electrocardiogram (ECG) serve as indicators of atrial conduction. P-wave duration (PWD) has been associated with various pathological conditions. The relationship between this factor and cardiovascular mortality remains insufficiently explored. To ascertain the association of PWD and cardiovascular and all-cause mortality in the MASHAD cohort study population.</div></div><div><h3>Method</h3><div>Participants were recruited from the Mashhad Stroke and Heart Atherosclerotic Disorder (MASHAD) cohort study. Participants' demographic information were recorded by checklist. Additionally, a comprehensive medical history was collected to identify cardiovascular risk factors, and history of pre-existing cardiovascular disease (CVD). A 12‑lead electrocardiogram (ECG) was obtained from the participants and they were subsequently categorized into two groups based on their PWD (≥ 120 msec and < 120 msec). All participants were followed for a minimum of 10 years for mortality assessment. We employed Cox regression to evaluate the relationship between PWD and cardiovascular and all-cause mortality. In order to evaluate the incremental predictive value of P wave duration, we calculated the net reclassification improvement (NRI) and integrated discrimination improvement (IDI) at 10-year follow-up timepoint. Subsequently, we developed Kaplan-Meier plots, time-dependent ROC curves, and restricted cubic splines (RCS) to thoroughly evaluate the association between PWD and cardiovascular mortality. Subgroup analysis was conducted to evaluate the impact of PWD across various distinct groups.</div></div><div><h3>Results</h3><div>A total of 8885 participants were enrolled in the study. Prolonged PWD was associated with higher all-cause, cardiovascular mortality in unadjusted model. After controlling for covariates, PWD remained significantly associated with all-cause and cardiovascular mortality in continuous form of it. However, PWD in categorical form did not show significant association with cardiovascular mortality. The addition of P wave duration to the conventional model did not provide statistically significant improvement in risk reclassification or discrimination for either all-cause or cardiovascular mortality. The RCS models indicated that the PWD displayed a positive linear correlation with the risk of all-cause mortality across all models. The time-dependent ROC curve demonstrated favorable predictive performance for the adjusted models at both the 5-year and 10-year timepoints. The subgroup analysis revealed no interaction among the subgroups in our statistically significant multivariable models (all p for interaction >0.05).</div></div><div><h3>Conclusion</h3><div>Continuous P-wave duration predicted all-cause and cardiovascular mortality, whereas the conventional 120 ms cut-off showed limited prognostic utility.</div></div>","PeriodicalId":15606,"journal":{"name":"Journal of electrocardiology","volume":"94 ","pages":"Article 154177"},"PeriodicalIF":1.2,"publicationDate":"2025-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145819564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-16DOI: 10.1016/j.jelectrocard.2025.154176
S.R. Breesha , S.S. Vinsley , M. Nisha
The FHR Detection employing dynamic encoding and parallel decoding swin transformer-based fetal R-peak detection network (DPSTFR-Net) was developed to address this issue. A cascaded Sparse Low-Rank and Kernel Recursive Least Squares (CSKL) filter is used to pre-process the input signals in order to eliminate high-frequency noise and baseline interference. DPSTFR-Net with adaptive position encoding is used to combine the position information of multiple receptor fields in order to perform the binary classification. Additionally, the parallel decoder's contextual information is used to reduce the impact of incorrectly categorized data points. Accuracy, precision, Mean Average Error (MAE), and other metrics are assessed using the PhysioNet/Computing in Cardiology Challenge database (PCDB) and the abdominal and direct fECG database (ADFECGDB). The proposed approach obtained 97.02 % accuracy, 98.25 % precision, 97.35 % recall, 97.28 % F1-score, 0.10 TNR, 0.55 FPR, and 0.56 MAE on the PCDB dataset. The approach obtained 97.52 % accuracy, 98.25 % precision, 97.05 % recall, 97.28 % F1-score, 0.09 TNR, 0.60 FPR, and 0.66 MAE for the ADFECGDB dataset. The outcomes of the experiment show that the proposed method is capable of effectively estimating FHR from abdominal ECG data. Commercial applications, such as long-term maternal and fetal monitoring systems, can use the proposed paradigm.
针对这一问题,开发了基于动态编码和并行解码的swin变压器胎儿r峰检测网络(DPSTFR-Net)。采用级联稀疏低秩和核递归最小二乘(CSKL)滤波器对输入信号进行预处理,以消除高频噪声和基线干扰。采用自适应位置编码的DPSTFR-Net对多个受体场的位置信息进行组合,实现二值分类。此外,并行解码器的上下文信息用于减少不正确分类数据点的影响。使用PhysioNet/Computing in Cardiology Challenge数据库(PCDB)和腹部和直接fECG数据库(ADFECGDB)评估准确性、精密度、平均误差(MAE)和其他指标。该方法在PCDB数据集上的准确率为97.02%,精密度为98.25%,召回率为97.35%,f1评分为97.28%,TNR为0.10,FPR为0.55,MAE为0.56。该方法对ADFECGDB数据集的准确率为97.52%,精密度为98.25%,召回率为97.05%,f1评分为97.28%,TNR为0.09,FPR为0.60,MAE为0.66。实验结果表明,该方法能够有效地从腹部心电图数据中估计出FHR。商业应用,如长期母体和胎儿监测系统,可以使用所提出的范例。
{"title":"Fetal R-peak detection using a swin transformer network with dynamic encoding and parallel decoding","authors":"S.R. Breesha , S.S. Vinsley , M. Nisha","doi":"10.1016/j.jelectrocard.2025.154176","DOIUrl":"10.1016/j.jelectrocard.2025.154176","url":null,"abstract":"<div><div>The FHR Detection employing dynamic encoding and parallel decoding swin transformer-based fetal R-peak detection network (DPSTFR-Net) was developed to address this issue. A cascaded Sparse Low-Rank and Kernel Recursive Least Squares (CSKL) filter is used to pre-process the input signals in order to eliminate high-frequency noise and baseline interference. DPSTFR-Net with adaptive position encoding is used to combine the position information of multiple receptor fields in order to perform the binary classification. Additionally, the parallel decoder's contextual information is used to reduce the impact of incorrectly categorized data points. Accuracy, precision, Mean Average Error (MAE), and other metrics are assessed using the PhysioNet/Computing in Cardiology Challenge database (PCDB) and the abdominal and direct fECG database (ADFECGDB). The proposed approach obtained 97.02 % accuracy, 98.25 % precision, 97.35 % recall, 97.28 % F1-score, 0.10 TNR, 0.55 FPR, and 0.56 MAE on the PCDB dataset. The approach obtained 97.52 % accuracy, 98.25 % precision, 97.05 % recall, 97.28 % F1-score, 0.09 TNR, 0.60 FPR, and 0.66 MAE for the ADFECGDB dataset. The outcomes of the experiment show that the proposed method is capable of effectively estimating FHR from abdominal ECG data. Commercial applications, such as long-term maternal and fetal monitoring systems, can use the proposed paradigm.</div></div>","PeriodicalId":15606,"journal":{"name":"Journal of electrocardiology","volume":"95 ","pages":"Article 154176"},"PeriodicalIF":1.2,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145870488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-13DOI: 10.1016/j.jelectrocard.2025.154154
Anton P.M. Gorgels MD, PhD
{"title":"Electrocardiographic criteria and algorithms to identify the culprit artery in inferior wall infarction. Back to the basics","authors":"Anton P.M. Gorgels MD, PhD","doi":"10.1016/j.jelectrocard.2025.154154","DOIUrl":"10.1016/j.jelectrocard.2025.154154","url":null,"abstract":"","PeriodicalId":15606,"journal":{"name":"Journal of electrocardiology","volume":"94 ","pages":"Article 154154"},"PeriodicalIF":1.2,"publicationDate":"2025-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145781155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-07DOI: 10.1016/j.jelectrocard.2025.154173
Giuseppe Mascia , Josep Brugada , Elena Arbelo , Andrea Minghini , Lorenzo Bianchi , Luca Barca , Nicola Pierucci , Cinzia Monaco , Paolo Di Donna , Italo Porto
A short-QT interval is a potential electrocardiographic finding, while short-QT syndrome (SQTS) is a rare, inherited channelopathy characterized by pathological shortening of the action potential duration leading to an increased risk of life-threatening arrhythmias. In contrast to the long QT syndrome (LQTS), data on the prevalence, diagnosis, risk stratification, treatment and prognosis of short-QT syndrome are scarce. Understanding the true risk of adverse events in exercise population or sporting activities by the patient with short-QT on 12‑leads electrocardiogram is complex: here, we summarize current knowledge and raise questions regarding the challenging relationship between the difficult SQTS diagnosis and exercise practice.
{"title":"Exercise practice and short-QT interval on ECG","authors":"Giuseppe Mascia , Josep Brugada , Elena Arbelo , Andrea Minghini , Lorenzo Bianchi , Luca Barca , Nicola Pierucci , Cinzia Monaco , Paolo Di Donna , Italo Porto","doi":"10.1016/j.jelectrocard.2025.154173","DOIUrl":"10.1016/j.jelectrocard.2025.154173","url":null,"abstract":"<div><div>A short-QT interval is a potential electrocardiographic finding, while short-QT syndrome (SQTS) is a rare, inherited channelopathy characterized by pathological shortening of the action potential duration leading to an increased risk of life-threatening arrhythmias. In contrast to the long QT syndrome (LQTS), data on the prevalence, diagnosis, risk stratification, treatment and prognosis of short-QT syndrome are scarce. Understanding the true risk of adverse events in exercise population or sporting activities by the patient with short-QT on 12‑leads electrocardiogram is complex: here, we summarize current knowledge and raise questions regarding the challenging relationship between the difficult SQTS diagnosis and exercise practice.</div></div>","PeriodicalId":15606,"journal":{"name":"Journal of electrocardiology","volume":"94 ","pages":"Article 154173"},"PeriodicalIF":1.2,"publicationDate":"2025-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145733855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-06DOI: 10.1016/j.jelectrocard.2025.154174
R. Brandon Stacey MD, MS , Ronald J. Prineas MD, PhD , Zhu-Ming Zhang MD, MPH , Bruce M. Psaty MD, PhD , Wayne Rosamond PhD , Lynne Wagenknecht DrPH , Elsayed Z. Soliman MD, MSc, MS
Introduction
It is unclear how differences in the electrocardiographic (ECG) definition of myocardial infarction (MI) impact detection rates and prognostic significance of silent MI (SMI).
Methods
This analysis included 9188 participants (57.4 % women, 20 % black, age 62.6 ± 6.0 years) enrolled in the Atherosclerosis Risk in Communities study who had serial ECGs obtained between visit 1 (1987–1989) and visit 4 (1996–1998). Exclusions included known cardiovascular disease (CVD) prior to visit 1, ECG findings of MI or bundle branch block (BBB) at visit 1, or an adjudicated fatal and non-fatal MI events between visits 1 and 4. Using the Minnesota Code (MC) ECG Classification and in the absence of adjudicated MI, the following SMI definitions were derived: Standard MC MI [major Q-wave abnormality, or minor Q-wave abnormality plus major ST/T abnormality], only major Q-wave abnormality, standard significant serial Q-wave changes [Q1 to Q7], expanded MC serial Q-wave changes[Q1 to Q8], standard MC significant serial Q-wave changes or Standard MC significant serial ST/T changes, and evolving MC BBB. Cox proportional hazard models were used to examine the association of different definitions of SMI (compared to no new MI or evolving BBB) with fatal or non-fatal MI events ascertained after visit 4 until December 2016.
Results
The prevalence of SMI ranged from 0.6 % to 7.0 % depending on the ECG criteria defining SMI. Presence of SMI was predictive of fatal/non-fatal MI regardless of the definition but with varying levels of association. Standard MC expanded serial Q-wave changes had the strongest adjusted relationship [Hazard Ratio: 2.53 (95 % Confidence Interval (CI): 1.60–4.01)] while evolving BBB had the weakest adjusted association [HR: 1.39 (95 % CI: 0.80–2.40)].
Conclusions
The prevalence and prognostic significance of SMI are impacted by the ECG criteria defining MI. A uniform approach(s) for detection of SMI in population studies which builds on the available standard definitions that fit different research scenarios is needed.
{"title":"Electrocardiographic criteria for silent myocardial infarction: Impact of different definitions on detection rates and prognostic significance in the atherosclerosis risk in communities (ARIC) study: A comparison with evolving bundle branch blocks","authors":"R. Brandon Stacey MD, MS , Ronald J. Prineas MD, PhD , Zhu-Ming Zhang MD, MPH , Bruce M. Psaty MD, PhD , Wayne Rosamond PhD , Lynne Wagenknecht DrPH , Elsayed Z. Soliman MD, MSc, MS","doi":"10.1016/j.jelectrocard.2025.154174","DOIUrl":"10.1016/j.jelectrocard.2025.154174","url":null,"abstract":"<div><h3>Introduction</h3><div>It is unclear how differences in the electrocardiographic (ECG) definition of myocardial infarction (MI) impact detection rates and prognostic significance of silent MI (SMI).</div></div><div><h3>Methods</h3><div>This analysis included 9188 participants (57.4 % women, 20 % black, age 62.6 ± 6.0 years) enrolled in the Atherosclerosis Risk in Communities study who had serial ECGs obtained between visit 1 (1987–1989) and visit 4 (1996–1998). Exclusions included known cardiovascular disease (CVD) prior to visit 1, ECG findings of MI or bundle branch block (BBB) at visit 1, or an adjudicated fatal and non-fatal MI events between visits 1 and 4. Using the Minnesota Code (MC) ECG Classification and in the absence of adjudicated MI, the following SMI definitions were derived: Standard MC MI [major Q-wave abnormality, or minor Q-wave abnormality plus major ST/T abnormality], only major Q-wave abnormality, standard significant serial Q-wave changes [Q1 to Q7], expanded MC serial Q-wave changes[Q1 to Q8], standard MC significant serial Q-wave changes or Standard MC significant serial ST/T changes, and evolving MC BBB. Cox proportional hazard models were used to examine the association of different definitions of SMI (compared to no new MI or evolving BBB) with fatal or non-fatal MI events ascertained after visit 4 until December 2016.</div></div><div><h3>Results</h3><div>The prevalence of SMI ranged from 0.6 % to 7.0 % depending on the ECG criteria defining SMI. Presence of SMI was predictive of fatal/non-fatal MI regardless of the definition but with varying levels of association. Standard MC expanded serial Q-wave changes had the strongest adjusted relationship [Hazard Ratio: 2.53 (95 % Confidence Interval (CI): 1.60–4.01)] while evolving BBB had the weakest adjusted association [HR: 1.39 (95 % CI: 0.80–2.40)].</div></div><div><h3>Conclusions</h3><div>The prevalence and prognostic significance of SMI are impacted by the ECG criteria defining MI. A uniform approach(s) for detection of SMI in population studies which builds on the available standard definitions that fit different research scenarios is needed.</div></div>","PeriodicalId":15606,"journal":{"name":"Journal of electrocardiology","volume":"94 ","pages":"Article 154174"},"PeriodicalIF":1.2,"publicationDate":"2025-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145733854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-29DOI: 10.1016/j.jelectrocard.2025.154160
Neha Pulath, Ramanathan Velayutham, Anish Bhargav, J. Barathkrishnan, Raja J. Selvaraj
Background
Atrial depolarization is represented by the P wave on the electrocardiogram (ECG), while atrial repolarization (Ta wave) is usually obscured by the QRS complex. In patients with third-degree atrioventricular block, the Ta wave can be observed and studied. Although atrial repolarization has been described in healthy subjects and in those with paroxysmal atrial fibrillation, it has not been studied in left ventricular dysfunction.
Methods
Patients with pacemaker implanted for third-degree AV block were studied. Group 1 included patients with normal ejection fraction (LVEF ≥55 %), and group 2 included patients with reduced ejection fraction (LVEF ≤40 %). Pacemakers were programmed to VVI pacing at 40 bpm, and six standard 12‑lead ECGs were recorded. P waves not followed by QRS complex for 500 ms were identified. PTa segments were extracted, averaged, and analyzed for duration, amplitude, axis and dispersion.
Results
Of 31 enrolled patients, 25 were included in the final analysis (13 in group 1, 12 in group 2). The mean PTa duration was 482 ± 36 ms and was not different between the groups. P wave duration, Ta amplitude, and Ta axis also were not different. Ta axis was northwest in all patients, opposite to the direction of atrial depolarisation. PTa dispersion was significantly higher in group 2 (74 ± 21 ms) compared to group 1 (54 ± 14 ms, p = 0.008).
Conclusion
PTa wave amplitude, duration, and axis are not altered in left ventricular dysfunction. PTa dispersion is increased in these patients and may be a marker of elevated risk for atrial arrhythmias.
心房去极化由心电图上的P波表示,而心房再极化(Ta波)通常被QRS复合体所掩盖。在三度房室传导阻滞患者中,可以观察和研究Ta波。虽然在健康受试者和阵发性心房颤动患者中已经有过心房复极的描述,但在左心室功能障碍中还没有研究过。方法对三度房室传导阻滞患者植入起搏器进行研究。第1组为射血分数正常(LVEF≥55%)患者,第2组为射血分数降低(LVEF≤40%)患者。起搏器设定为每分钟40次的VVI起搏,并记录6个标准的12导联心电图。在500 ms内未发现QRS复合体的P波。提取PTa片段,平均,并分析其持续时间,振幅,轴和弥散度。结果31例入组患者中,25例纳入最终分析(1组13例,2组12例)。平均PTa持续时间为482±36 ms,各组间差异无统计学意义。P波持续时间、Ta振幅和Ta轴也无差异。所有患者Ta轴均向西北方向,与心房去极化方向相反。2组PTa弥散度(74±21 ms)显著高于1组(54±14 ms, p = 0.008)。结论pta波振幅、持续时间和轴向在左心功能障碍中未发生改变。PTa弥散度在这些患者中增加,可能是心房心律失常风险升高的标志。
{"title":"Atrial repolarization in patients with left ventricular dysfunction","authors":"Neha Pulath, Ramanathan Velayutham, Anish Bhargav, J. Barathkrishnan, Raja J. Selvaraj","doi":"10.1016/j.jelectrocard.2025.154160","DOIUrl":"10.1016/j.jelectrocard.2025.154160","url":null,"abstract":"<div><h3>Background</h3><div>Atrial depolarization is represented by the P wave on the electrocardiogram (ECG), while atrial repolarization (Ta wave) is usually obscured by the QRS complex. In patients with third-degree atrioventricular block, the Ta wave can be observed and studied. Although atrial repolarization has been described in healthy subjects and in those with paroxysmal atrial fibrillation, it has not been studied in left ventricular dysfunction.</div></div><div><h3>Methods</h3><div>Patients with pacemaker implanted for third-degree AV block were studied. Group 1 included patients with normal ejection fraction (LVEF ≥55 %), and group 2 included patients with reduced ejection fraction (LVEF ≤40 %). Pacemakers were programmed to VVI pacing at 40 bpm, and six standard 12‑lead ECGs were recorded. P waves not followed by QRS complex for 500 ms were identified. PTa segments were extracted, averaged, and analyzed for duration, amplitude, axis and dispersion.</div></div><div><h3>Results</h3><div>Of 31 enrolled patients, 25 were included in the final analysis (13 in group 1, 12 in group 2). The mean PTa duration was 482 ± 36 ms and was not different between the groups. P wave duration, Ta amplitude, and Ta axis also were not different. Ta axis was northwest in all patients, opposite to the direction of atrial depolarisation. PTa dispersion was significantly higher in group 2 (74 ± 21 ms) compared to group 1 (54 ± 14 ms, <em>p</em> = 0.008).</div></div><div><h3>Conclusion</h3><div>PTa wave amplitude, duration, and axis are not altered in left ventricular dysfunction. PTa dispersion is increased in these patients and may be a marker of elevated risk for atrial arrhythmias.</div></div>","PeriodicalId":15606,"journal":{"name":"Journal of electrocardiology","volume":"94 ","pages":"Article 154160"},"PeriodicalIF":1.2,"publicationDate":"2025-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145682159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-26DOI: 10.1016/j.jelectrocard.2025.154161
Almaz Rehman Koolikad, Syed Ahmad Khan, Muhammad Shahzaib, Bushra Arif, Shivam Singla, Bhavna Singla, Muhammad Subhan, Abida Perveen, Jahanzeb Malik
Objective
To evaluate the diagnostic accuracy and clinical impact of 18‑lead electrocardiography compared with conventional 12‑lead ECG in patients with suspected acute coronary syndromes (ACS).
Methods
A systematic review and meta-analysis were conducted by searching PubMed, Embase, Scopus, and the Cochrane Library from inception to August 2025. Eligible studies compared 18‑lead with 12‑lead ECG using angiography, biomarkers, or imaging as reference standards. Data were extracted to construct 2 × 2 tables where available, and pooled sensitivity, specificity, and risk ratios were calculated using random-effects models. Risk of bias was assessed with QUADAS-2, and certainty of evidence was graded with GRADE.
Results
Seven studies met the inclusion criteria, of which four provided extractable diagnostic accuracy data (n ≈ 535). Across studies, 18‑lead ECG significantly improved sensitivity for posterior myocardial infarction (≈80–85 % vs 55–65 % with 12‑lead) and right ventricular infarction (≈78 % vs 58 %) while preserving specificity (≈90 %). Pooled analysis demonstrated a 34 % relative improvement in diagnostic yield (RR 1.34, 95 % CI 1.18–1.55; p < 0.01). Approximately 10–15 % of patients initially classified as NSTEMI were reclassified as STEMI-equivalents using 18‑lead recordings. Evidence of earlier catheterization laboratory activation was noted in emergency department cohorts.
Conclusion
Eighteen‑lead ECG enhances detection of posterior and right ventricular infarctions without loss of specificity and supports earlier intervention. Broader clinical adoption and outcome-focused trials are warranted.
目的:评价18导联心电图与常规12导联心电图对疑似急性冠脉综合征(ACS)的诊断准确性及临床意义。方法:通过检索PubMed、Embase、Scopus和Cochrane Library自成立至2025年8月的文献进行系统评价和meta分析。符合条件的研究比较了18导联和12导联心电图,使用血管造影、生物标志物或成像作为参考标准。在可能的情况下,提取数据构建2 × 2表,并使用随机效应模型计算合并敏感性、特异性和风险比。偏倚风险采用QUADAS-2进行评估,证据的确定性采用GRADE分级。结果:7项研究符合纳入标准,其中4项提供可提取的诊断准确性数据(n≈535)。在所有研究中,18导联心电图显著提高了对后置心肌梗死(≈80- 85% vs 55- 65%)和右心室梗死(≈78% vs 58%)的敏感性,同时保留了特异性(≈90%)。合并分析显示,诊断率相对提高34% (RR 1.34, 95% CI 1.18-1.55; p)。结论:十八导联心电图增强了对后室和右室梗死的检测,而不丧失特异性,支持早期干预。更广泛的临床应用和以结果为重点的试验是必要的。
{"title":"Diagnostic accuracy of 18-lead versus 12-lead electrocardiography in acute coronary syndrome: A systematic review and meta-analysis","authors":"Almaz Rehman Koolikad, Syed Ahmad Khan, Muhammad Shahzaib, Bushra Arif, Shivam Singla, Bhavna Singla, Muhammad Subhan, Abida Perveen, Jahanzeb Malik","doi":"10.1016/j.jelectrocard.2025.154161","DOIUrl":"10.1016/j.jelectrocard.2025.154161","url":null,"abstract":"<div><h3>Objective</h3><div>To evaluate the diagnostic accuracy and clinical impact of 18‑lead electrocardiography compared with conventional 12‑lead ECG in patients with suspected acute coronary syndromes (ACS).</div></div><div><h3>Methods</h3><div>A systematic review and meta-analysis were conducted by searching PubMed, Embase, Scopus, and the Cochrane Library from inception to August 2025. Eligible studies compared 18‑lead with 12‑lead ECG using angiography, biomarkers, or imaging as reference standards. Data were extracted to construct 2 × 2 tables where available, and pooled sensitivity, specificity, and risk ratios were calculated using random-effects models. Risk of bias was assessed with QUADAS-2, and certainty of evidence was graded with GRADE.</div></div><div><h3>Results</h3><div>Seven studies met the inclusion criteria, of which four provided extractable diagnostic accuracy data (n ≈ 535). Across studies, 18‑lead ECG significantly improved sensitivity for posterior myocardial infarction (≈80–85 % vs 55–65 % with 12‑lead) and right ventricular infarction (≈78 % vs 58 %) while preserving specificity (≈90 %). Pooled analysis demonstrated a 34 % relative improvement in diagnostic yield (RR 1.34, 95 % CI 1.18–1.55; <em>p</em> < 0.01). Approximately 10–15 % of patients initially classified as NSTEMI were reclassified as STEMI-equivalents using 18‑lead recordings. Evidence of earlier catheterization laboratory activation was noted in emergency department cohorts.</div></div><div><h3>Conclusion</h3><div>Eighteen‑lead ECG enhances detection of posterior and right ventricular infarctions without loss of specificity and supports earlier intervention. Broader clinical adoption and outcome-focused trials are warranted.</div></div>","PeriodicalId":15606,"journal":{"name":"Journal of electrocardiology","volume":"94 ","pages":"Article 154161"},"PeriodicalIF":1.2,"publicationDate":"2025-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145668673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}