1.Bursts beneath the surface: Using the electrocardiogram as a blueprint to arrhythmogenesis.
Jose Donato A. MAGNO ; Michael Joseph F. AGBAYANI ; Jerome Joseph T. GALEON ; Amraphel L. NICOLAS ; Peter Carlo M. NIERRAS
Philippine Journal of Cardiology 2026;54(S1):82-84
The surface electrocardiogram (ECG) can provide many clues to a patient’s underlying medical condition or tendency for arrhythmogenesis. An 80-year-old man with severe aortic stenosis and an implantable cardioverter-defibrillator (ICD) for advanced heart block presented with burping, chest discomfort and intermittent pounding sensations. His ECG showed atrial fibrillation with intermittent ventricular pacing at 60 bpm characterized by irregularly irregular rhythm, absent P waves, narrow intrinsic QRS complexes alternating with wide-paced beats (left bundle branch block [LBBB] morphology, superior axis) and visible pacing spikes. Device interrogation revealed ventricular tachycardia (VT) storm with multiple appropriate ICD shocks explaining his pounding sensations. This report highlights two key teaching points: recognizing atrial fibrillation during ventricular pacing—a frequently missed diagnosis affecting nearly half of patients with pacemakers—and managing VT storm to reduce shock burden. After device reprogramming and antiarrhythmic adjustment, the patient became asymptomatic.
Human ; Male ; Aged: 65-79 Yrs Old ; Thorax ; Teaching ; Tachycardia, Ventricular ; Electrocardiography ; Atrial Fibrillation ; Bundle-branch Block ; Constriction, Pathologic
2.Epidemiologic burden of atrial fibrillation-related hospitalization in the Philippines.
Erdie C. FADREGUILAN ; Bernadette A. TUMANAN-MENDOZA ; Victor L. MENDOZA ; Giselle G. GERVACIO
Philippine Journal of Cardiology 2026;54(1):72-76
BACKGROUND
Hospitalization is a major complication of atrial fibrillation (AF) and its burden has been rising across Asia. In Korea alone, AF-related hospitalizations increased by 420% from 2006 to 2015. However, comparable data are lacking in the Philippines. This study aimed to determine the prevalence of AF-related hospitalizations among adult patients aged 19 years or older using database claims of the Philippine Health Insurance Corporation (PhilHealth) in 2017 and 2018.
RESULTSIn both 2017 and 2018, approximately 19–20 per 10,000 total hospital admissions were due to AF. The median patient age was 68 years in 2017 and 69 years in 2018. Most admissions occurred in private tertiary hospitals located in urban areas, with a median length of stay of three days. The in-hospital mortality rate was 1.1% for both years.
CONCLUSIONAmong the arrhythmias, AF was the most common cause of hospitalization in the Philippines in 2017 and 2018, which accounted for 19 per 10,000 hospitalizations. Despite this burden, the associated in-hospital mortality rate remained low.
Atrial Fibrillation ; Hospitalization ; Mortality ; Philippines
3.Epidemiologic burden of atrial fibrillation-related hospitalization in the Philippines.
Erdie C. FADREGUILAN ; Bernadette A. TUMANAN-MENDOZA ; Victor L. MENDOZA ; Giselle G. GERVACIO
Philippine Journal of Cardiology 2026;54(1):72-76
BACKGROUND
Hospitalization is a major complication of atrial fibrillation (AF) and its burden has been rising across Asia. In Korea alone, AF-related hospitalizations increased by 420% from 2006 to 2015. However, comparable data are lacking in the Philippines. This study aimed to determine the prevalence of AF-related hospitalizations among adult patients aged 19 years or older using database claims of the Philippine Health Insurance Corporation (PhilHealth) in 2017 and 2018.
RESULTSIn both 2017 and 2018, approximately 19–20 per 10,000 total hospital admissions were due to AF. The median patient age was 68 years in 2017 and 69 years in 2018. Most admissions occurred in private tertiary hospitals located in urban areas, with a median length of stay of three days. The in-hospital mortality rate was 1.1% for both years.
CONCLUSIONAmong the arrhythmias, AF was the most common cause of hospitalization in the Philippines in 2017 and 2018, which accounted for 19 per 10,000 hospitalizations. Despite this burden, the associated in-hospital mortality rate remained low.
Atrial Fibrillation ; Hospitalization ; Mortality ; Philippines
4.Thyroid-Stimulating Hormone (TSH)-Secretory Macroadenoma Presenting with Recurrent Atrial Fibrillation in Failure
Muzhaffar Mokhtar ; Masliza Hanuni Mohd Ali ; Wan Mohd Hafez Wan Hamzah
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):95-96
Introduction:
Accounting for less than 2% of all pituitary adenomas, TSHsecreting pituitary adenomas (TSHoma) are an uncommon
cause of hyperthyroidism. Majority are macroadenomas
with delayed diagnosis as most patients are unwittingly
treated for primary hyperthyroidism. Recurring discordant
thyroid function test (TFT) with elevated thyroidstimulating hormone (TSH) and Free T4 is a hint and
warrants additional investigation to facilitate diagnosis.
Case:
We report a case of a 48-year-old female who was treated
for primary hyperthyroidism since her late 20s with
multiple admissions for recurrent congestive heart failure and atrial fibrillation. The cardiac issue was preceded by
worsening thyrotoxicosis. Previous thyroid autoantibodies
were negative. Of note, she had recurring discordant
TFT results from two different assays (TSH:84.7, free
thyroxine 4 [FT4]:75.43) (TSH:37.86, FT4:27.34) during
admission, excluding assay interference and prompting
toward TSHoma or Resistance to Thyroid Hormone (RTH).
Examination revealed a large goiter (10 × 8 cm) hard in
consistency, and pansystolic murmur over tricuspid area.
No thyroid eye disease nor bitemporal hemianopia or
clinical sign of acromegaly.
Echocardiography showed dilated left atrium and mild
to moderate tricuspid regurgitation with preserved
ejection fraction. Thyroid-releasing hormone (TRH)
stimulation test demonstrated blunted TSH response
confirming TSHoma. Anterior pituitary hormone profile
revealed normal insulin-like growth factor-1 level with
suppressed sex hormones and prolactin, thus excluding
co-secreting hormone. Sex hormone-binding globulin
level, α-subunit, and T3 suppression test were not done
due to unavailability. Magnetic resonance imaging
pituitary uncovered pituitary mass measuring (2.6 × 3.3 ×
2.2 cm) suggestive of macroadenoma with encasement of
cavernous internal carotid arteries and cavernous sinus
compression. Computed tomography neck revealed diffuse
thyroid enlargement with compressive mass effects onto
adjacent structure with trachea narrowing. After discussing
with a multidisciplinary team, we planned her for total
thyroidectomy followed by transsphenoidal surgery.
Conclusion
Late presentation and diagnosis in TSHoma remain a
major challenge. TFT interpretation is fundamental in
identifying the causes of secondary hyperthyroidism to
avert detrimental sequalae and to guide optimal treatment.
Atrial Fibrillation
;
Thyrotropin
5.Electrocardiographic manifestations of hospitalized adult patients with coronavirus disease 19 (COVID-19): UP-PGH DCVM ECG study.
Felix Eduardo R. PUNZALAN ; Paul Anthony O. ALAD ; Tam Adrian P. AYA-AY ; Kaye Eunice L. LUSTESTICA ; Nigel Jeronimo C. SANTOS ; Jaime Alfonso M. AHERRERA ; Elmer Jasper B. LLANES ; Giselle G. GERVACIO ; Eugenio B. REYES ; John C. AÑONUEVO
Acta Medica Philippina 2025;59(16):41-45
BACKGROUND AND OBJECTIVE
COVID-19 has been associated with cardiac injury, often detectable through electrocardiographic (ECG) changes. This study seeks to characterize the cardiovascular and electrocardiographic profiles of adult patients diagnosed with COVID-19.
METHODSThis study included adult patients with confirmed COVID-19 from June 2021 to June 2022. Clinical profiles and 12-lead ECG tracings were obtained from electronic medical records and reviewed independently by three cardiologists. Descriptive analysis was performed to summarize the cardiovascular and electrocardiographic findings in this population.
RESULTSThe study included 998 COVID-19 patients (mean age: 50 years; 53.7% male). The most common comorbidities were hypertension, diabetes, and dyslipidemia. A majority (31.36%) presented with severe COVID-19 infection. The most frequent significant ECG abnormalities observed at admission were sinus tachycardia (22.8%), and atrial fibrillation (11.02%). Additional ischemic findings included ST segment depression (2.91%), T-wave inversion (1.70%), and ST segment elevation (2.71%).
CONCLUSIONThe baseline ECG findings among COVID-19 patients were predominantly normal; however, significant abnormalities were also identified. The most frequent abnormalities included sinus tachycardia, atrial fibrillation, and ischemic changes, all of which may have clinical implications.
Human ; Coronavirus Disease 19 ; Covid-19 ; Electrocardiography ; Atrial Fibrillation
6.An atrial fibrillation prediction model based on quantitative features of electrocardiogram during sinus rhythm in the Chinese population.
Xiaoqing ZHU ; Yajun SHI ; Juan SHEN ; Qingsong WANG ; Tingting SONG ; Jiancheng XIU ; Tao CHEN ; Jun GUO
Journal of Southern Medical University 2025;45(2):223-228
OBJECTIVES:
To develop an early atrial fibrillation (AF) risk prediction model based on large-scale electrocardiogram (ECG) data from the Chinese population.
METHODS:
The data of multiple ECG records of 30 383 patients admitted in the Chinese PLA General Hospital between 2009 and 2023 were randomly divided into the training set and the internal testing set in a 7:3 ratio. The predictive factors were selected based on the training set using univariate analysis, LASSO regression, and the Boruta algorithm. Cox proportional hazards regression was used to establish the ECG model and the composite model incorporating age, gender, and ECG model score. The discrimination power, calibration, and clinical net benefits of the models were evaluated using the area under the receiver operating characteristic curve (AUROC), calibration curves, and decision curves.
RESULTS:
The cohort included 51.1% male patients with a median age of the patients of 51 (36, 62) years and an AF incidence of 4.5% (1370/30 383). In the ECG model, the parameters related to the P wave and QRS complex were identified as significant predictors. In the testing set, the AUROC of the ECG model for predicting 5-year AF risk was 0.77 (95% CI: 0.74-0.80), which was increased to 0.81 (95% CI: 0.78-0.83) after incorporating age and gender, with a net reclassification improvement of 0.123 and an integrated discrimination improvement of 0.04 (P<0.05). The calibration curve of the model was close to the diagonal line. Decision curve analysis showed that the clinical net benefit of the composite model was higher than that of the ECG model across the majority of threshold probability.
CONCLUSIONS
The composite model incorporating quantitative ECG features during sinus rhythm, along with age and gender, can effectively predict AF risk in the Chinese population, thus providing a low-cost screening tool for early AF risk assessment and management.
Humans
;
Atrial Fibrillation/epidemiology*
;
Electrocardiography
;
Middle Aged
;
Male
;
Female
;
China/epidemiology*
;
Proportional Hazards Models
;
Adult
;
Risk Factors
;
Risk Assessment
;
East Asian People
7.A lightweight classification network for single-lead atrial fibrillation based on depthwise separable convolution and attention mechanism.
Yong HONG ; Xin ZHANG ; Mingjun LIN ; Qiucen WU ; Chaomin CHEN
Journal of Southern Medical University 2025;45(3):650-660
OBJECTIVES:
To design a deep learning model that balances model complexity and performance to enable its integration into wearable ECG monitoring devices for automated diagnosis of atrial fibrillation.
METHODS:
This study was performed based on data from 84 patients with atrial fibrillation, 25 patients with atrial fibrillation, and 18 subjects without obvious arrhythmia collected from the publicly available datasets LTAFDB, AFDB, and NSRDB, respectively. A lightweight attention network based on depthwise separable convolution and fusion of channel-spatial information, namely DSC-AttNet, was proposed. Depthwise separable convolution was introduced to replace standard convolution and reduce model parameters and computational complexity to realize high efficiency and light weight of the model. The multilayer hybrid attention mechanism was embedded to compute the attentional weights of the channels and spatial information at different scales to improve the feature expression ability of the model. Ten-fold cross-validation was performed on LTAFDB, and external independent testing was conducted on AFDB and NSRDB datasets.
RESULTS:
DSC-AttNet achieved a ten-fold average accuracy of 97.33% and a precision of 97.30% on the test set, both of which outperformed the other 4 comparison models as well as the 3 classical models. The accuracy of the model on the external test set reached 92.78%, better than those of the 3 classical models. The number of parameters of DSC-AttNet was 1.01M, and the computational volume was 27.19G, both smaller than the 3 classical models.
CONCLUSIONS
This proposed method has a smaller complexity, achieves better classification performance, and has a better generalization ability for atrial fibrillation classification.
Atrial Fibrillation/diagnosis*
;
Humans
;
Electrocardiography
;
Deep Learning
;
Wearable Electronic Devices
;
Neural Networks, Computer
8.Epidemiology of atrial fibrillation/atrial flutter and its risk factors from 1990 to 2021: a systematic analysis and Mendelian randomization study based on the China and Global Burden of Disease Study 2021.
Huihua MA ; Kuipo YAN ; Gang LIU ; Yazhou XU ; Lei ZHANG ; Yizhuo LI
Journal of Southern Medical University 2025;45(10):2182-2190
OBJECTIVES:
To analyze the changes in disease burden and risk factors of atrial fibrillation/atrial flutter (AF/AFL) in China and globally from 1990 to 2021 to provide epidemiological evidence for developing effective preventive measures for AF/AFL in China.
METHODS:
Based on data from the Global Burden of Disease Study 2021, we analyzed sex- and age-specific AF/AFL burden metrics across 204 countries or territories. Age-standardized incidence rate (ASIR), prevalence, mortality rate (ASMR), and disability-adjusted life-years (DALYs) rate (ASDR) were calculated. Joinpoint regression was employed to compute average annual percentage changes (AAPC) in trends. The risk factors were systematically evaluated and further validated using Mendelian randomization analysis.
RESULTS:
From 1990 to 2021, China experienced an increase in ASIR of AF/AFL (from 42.63 to 44.93 per 100 000), contrasting with the global decline. While China's ASMR decreased (from 4.93 to 4.33 per 100 000), global ASMR rose slightly (from 4.24 to 4.36 per 100 000). China's ASDR remained stable at 93.29 per 100 000, whereas global ASDR increased marginally (100.81 to 101.40 per 100 000). Significant sex disparities were observed: males showed higher ASIR and ASDR, while females exhibited greater ASMR and ASDR. China had higher incidence and prevalence but lower mortality and DALY rates compared to global averages. In 2021, the key risk factors for AF/AFL included elevated systolic blood pressure, high BMI, smoking, alcohol use, high-sodium diet, and low temperature. Gender-specific patterns emerged: smoking was predominant in males, whereas high BMI disproportionately affected females.
CONCLUSIONS
AF/AFL incidence and prevalence keep increasing in China, and its large population base and demographic aging pose significant public health challenges. Maintaining healthy lifestyle habits, including smoking cessation, alcohol moderation, and a low-sodium diet can help to lower AF/AFL incidence, and regular screenings is crucial for its early detection and treatment.
Humans
;
China/epidemiology*
;
Risk Factors
;
Atrial Flutter/epidemiology*
;
Atrial Fibrillation/epidemiology*
;
Mendelian Randomization Analysis
;
Male
;
Female
;
Global Burden of Disease
;
Incidence
;
Prevalence
;
Middle Aged
;
Disability-Adjusted Life Years
;
Aged
9.Acupuncture activates vagus nerve-macrophage axis and improves cardiac electrophysiology and inflammatory response in rats with atrial fibrillation via α7nAChR-JAK2/STAT3 pathway.
Zhi-Han LI ; Wen-Min YANG ; Qi HUANG ; Guang-Xia SHI ; Cun-Zhi LIU ; Yu-Qin ZHANG
Journal of Integrative Medicine 2025;23(4):398-414
OBJECTIVE:
The occurrence and development of atrial fibrillation (AF) are influenced by the autonomic nervous system and inflammation. Acupuncture is an effective treatment for AF. This study explored the protective effects of acupuncture in a rat model of paroxysmal AF and investigated its mechanisms.
METHODS:
Male Sprague-Dawley rats (n = 130) were randomly divided into blank control (Con), sham operation (Sham), AF, and acupuncture treatment (Acu) groups. A paroxysmal AF model was established by rapid atrial pacing through the jugular vein. Rats in the Acu group were immobilized to receive acupuncture treatment at Neiguan acupoint (PC6) for 20 min daily for seven days. The other groups were immobilized for the same duration over the treatment period but did not receive acupuncture. The AF induction rate, AF duration, cardiac electrophysiological parameters, and heart rate variability were evaluated by monitoring surface electrocardiogram and vagus nerve discharge signals. After the intervention, the rats were euthanized, and atrial morphology was assessed using haematoxylin and eosin staining. The expression of macrophage F4/80 antigen (F4/80) and cluster of differentiation (CD) 86 in atrial myocardial tissue was detected using immunohistochemistry, immunofluorescence and flow cytometry. The expression levels or contents of interleukin (IL)-1β, IL-6, tumor necrosis factor-α (TNF-α), α7 nicotinic acetylcholine receptor (α7nAChR), phosphorylated Janus kinase 2 (p-JAK2), and phosphorylated signal transducer and activator of transcription 3 (p-STAT3) in atrial myocardial tissue were detected using Western blotting, reverse transcription-quantitative polymerase chain reaction, or enzyme-linked immunosorbent assay. The role of α7nAChR in acupuncture treatment was verified by intraperitoneal injection of the α7nAChR antagonist methyllycaconitine (MLA).
RESULTS:
Compared with the AF group, acupuncture significantly reduced AF duration and induction rate, improved cardiac electrophysiology by enhancing vagus nerve activity and regulating autonomic balance. It also decreased the pro-inflammatory M1 macrophage proportion, alleviating myocardial injury and infiltration. MLA weakened acupuncture's electrophysiological improvement and anti-inflammatory effect. Results suggest that acupuncture triggers the α7nAChR-JAK2/STAT3 pathway and exerts cardioprotection via neuroimmune regulation.
CONCLUSION
Acupuncture significantly reduced the AF induction rate, shortened AF duration, improved cardiac electrophysiological parameters, enhanced vagus nerve activity, and decreased the expression of pro-inflammatory M1 macrophages and inflammatory factors in rats with paroxysmal AF. Its positive effects are related to the activation of the α7nAChR-mediated JAK2/STAT3 signalling pathway, indicating that the interaction between cardiac vagus nerve and macrophages may be a potential target for acupuncture in the prevention and treatment of AF. Please cite this article as: Li ZH, Yang WM, Huang Q, Shi GX, Liu CZ, Zhang YQ. Acupuncture activates vagus nerve-macrophage axis and improves cardiac electrophysiology and inflammatory response in rats with atrial fibrillation via α7nAChR-JAK2/STAT3 pathway. J Integr Med. 2025; 23(4): 398-414.
Animals
;
Male
;
Rats, Sprague-Dawley
;
STAT3 Transcription Factor/metabolism*
;
alpha7 Nicotinic Acetylcholine Receptor/metabolism*
;
Janus Kinase 2/metabolism*
;
Atrial Fibrillation/metabolism*
;
Vagus Nerve/physiopathology*
;
Rats
;
Acupuncture Therapy
;
Signal Transduction
;
Macrophages/metabolism*
;
Inflammation/therapy*
10.Technical standards for performing radiofrequency catheter ablation for atrial fibrillation: a series of consortium standards.
Chinese Journal of Internal Medicine 2025;64(1):23-35
Atrial fibrillation (AF) has emerged as a major global cardiovascular disease in the 21st century. In China, there are greater than 12 million patients with AF, and its incidence continues to rise. AF affects patients' quality of life and significantly increases the risks of mortality, stroke, heart failure, cognitive impairment, and dementia. In recent years, multiple clinical guidelines have expanded the indications for catheter ablation and raised its level of recommendation. Concurrently, there has been a rapid and sustained increase in the number of AF ablation procedures performed across China. Among these, radiofrequency catheter ablation remains the most used method. Consequently, the Chinese Heart Rhythm Society of the Chinese Society of Biomedical Engineering, in collaboration with 40 arrhythmia centers and 60 leading clinical experts specializing in AF catheter ablation, developed a comprehensive set of standards. These standards were developed based on extensive clinical experience accumulated in recent years and the latest national and international AF guidelines and consensus documents. They address five critical domains: periprocedural management, intra-atrial septal puncture, anatomical reconstruction and electroanatomic mapping, ablation, and complication identification and management. By providing a structured framework, these standards aim to guide AF catheter ablation practice, thereby enhancing procedural safety and efficacy.
Humans
;
Catheter Ablation/standards*
;
Atrial Fibrillation/surgery*
;
China


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