In healthcare,the persistent challenge of arrhythmias,a leading cause of global mortality,has sparked extensive research into the automation of detection using machine learning(ML)algorithms.However,traditional ML and...In healthcare,the persistent challenge of arrhythmias,a leading cause of global mortality,has sparked extensive research into the automation of detection using machine learning(ML)algorithms.However,traditional ML and AutoML approaches have revealed their limitations,notably regarding feature generalization and automation efficiency.This glaring research gap has motivated the development of AutoRhythmAI,an innovative solution that integrates both machine and deep learning to revolutionize the diagnosis of arrhythmias.Our approach encompasses two distinct pipelines tailored for binary-class and multi-class arrhythmia detection,effectively bridging the gap between data preprocessing and model selection.To validate our system,we have rigorously tested AutoRhythmAI using a multimodal dataset,surpassing the accuracy achieved using a single dataset and underscoring the robustness of our methodology.In the first pipeline,we employ signal filtering and ML algorithms for preprocessing,followed by data balancing and split for training.The second pipeline is dedicated to feature extraction and classification,utilizing deep learning models.Notably,we introduce the‘RRI-convoluted trans-former model’as a novel addition for binary-class arrhythmias.An ensemble-based approach then amalgamates all models,considering their respective weights,resulting in an optimal model pipeline.In our study,the VGGRes Model achieved impressive results in multi-class arrhythmia detection,with an accuracy of 97.39%and firm performance in precision(82.13%),recall(31.91%),and F1-score(82.61%).In the binary-class task,the proposed model achieved an outstanding accuracy of 96.60%.These results highlight the effectiveness of our approach in improving arrhythmia detection,with notably high accuracy and well-balanced performance metrics.展开更多
This editorial,comments on the article by Spartalis et al published in the recent issue of the World Journal of Cardiology.We here provide an outlook on potential ethical concerns related to the future application of ...This editorial,comments on the article by Spartalis et al published in the recent issue of the World Journal of Cardiology.We here provide an outlook on potential ethical concerns related to the future application of gene therapy in the field of inherited arrhythmias.As monogenic diseases with no or few therapeutic options available through standard care,inherited arrhythmias are ideal candidates to gene therapy in their treatment.Patients with inherited arrhythmias typically have a poor quality of life,especially young people engaged in agonistic sports.While genome editing for treatment of inherited arrhythmias still has theoretical application,advances in CRISPR/Cas9 technology now allows the generation of knock-in animal models of the disease.However,clinical translation is somehow expected soon and this make consistent discussing about ethical concerns related to gene editing in inherited arrhythmias.Genomic off-target activity is a known technical issue,but its relationship with ethnical and individual genetical diversity raises concerns about an equitable accessibility.Meanwhile,the costeffectiveness may further limit an equal distribution of gene therapies.The economic burden of gene therapies on healthcare systems is is increasingly recognized as a pressing concern.A growing body of studies are reporting uncertainty in payback periods with intuitive short-term effects for insurance-based healthcare systems,but potential concerns for universal healthcare systems in the long term as well.Altogether,those aspects strongly indicate a need of regulatory entities to manage those issues.展开更多
This research introduces an innovative ensemble approach,combining Deep Residual Networks(ResNets)and Bidirectional Gated Recurrent Units(BiGRU),augmented with an Attention Mechanism,for the classification of heart ar...This research introduces an innovative ensemble approach,combining Deep Residual Networks(ResNets)and Bidirectional Gated Recurrent Units(BiGRU),augmented with an Attention Mechanism,for the classification of heart arrhythmias.The escalating prevalence of cardiovascular diseases necessitates advanced diagnostic tools to enhance accuracy and efficiency.The model leverages the deep hierarchical feature extraction capabilities of ResNets,which are adept at identifying intricate patterns within electrocardiogram(ECG)data,while BiGRU layers capture the temporal dynamics essential for understanding the sequential nature of ECG signals.The integration of an Attention Mechanism refines the model’s focus on critical segments of ECG data,ensuring a nuanced analysis that highlights the most informative features for arrhythmia classification.Evaluated on a comprehensive dataset of 12-lead ECG recordings,our ensemble model demonstrates superior performance in distinguishing between various types of arrhythmias,with an accuracy of 98.4%,a precision of 98.1%,a recall of 98%,and an F-score of 98%.This novel combination of convolutional and recurrent neural networks,supplemented by attention-driven mechanisms,advances automated ECG analysis,contributing significantly to healthcare’s machine learning applications and presenting a step forward in developing non-invasive,efficient,and reliable tools for early diagnosis and management of heart diseases.展开更多
BACKGROUND Individuals diagnosed with gastrointestinal tumors are at an increased risk of developing cardiovascular diseases.Among which,ventricular arrhythmia is a prevalent clinical concern.This suggests that ventri...BACKGROUND Individuals diagnosed with gastrointestinal tumors are at an increased risk of developing cardiovascular diseases.Among which,ventricular arrhythmia is a prevalent clinical concern.This suggests that ventricular arrhythmias may have predictive value in the prognosis of patients with gastrointestinal tumors.AIM To explore the prognostic value of ventricular arrhythmias in patients with gastrointestinal tumors receiving surgery.METHODS We retrospectively analyzed data from 130 patients undergoing gastrointestinal tumor resection.These patients were evaluated by a 24-h ambulatory electrocardiogram(ECG)at the Sixth Affiliated Hospital of Sun Yat-sen University from January 2018 to June 2020.Additionally,41 general healthy age-matched and sexmatched controls were included.Patients were categorized into survival and non-survival groups.The primary endpoint was all-cause mortality,and secondary endpoints included major adverse cardiovascular events(MACEs).RESULTS Colorectal tumors comprised 90%of cases.Preoperative ambulatory ECG monitoring revealed that among the 130 patients with gastrointestinal tumors,100(76.92%)exhibited varying degrees of premature ventricular contractions(PVCs).Ten patients(7.69%)manifested non-sustained ventricular tachycardia(NSVT).The patients with gastrointestinal tumors exhibited higher PVCs compared to the healthy controls on both conventional ECG[27(21.3)vs 1(2.5),P=0.012]and 24-h ambulatory ECG[14(1.0,405)vs 1(0,6.5),P<0.001].Non-survivors had a higher PVC count than survivors[150.50(7.25,1690.50)vs 9(0,229.25),P=0.020].During the follow-up period,24 patients died and 11 patients experienced MACEs.Univariate analysis linked PVC>35/24 h to all-cause mortality,and NSVT was associated with MACE.However,neither PVC burden nor NSVT independently predicted outcomes according to multivariate analysis.CONCLUSION Patients with gastrointestinal tumors exhibited elevated PVCs.PVCs>35/24 h and NSVT detected by 24-h ambulatory ECG were prognostically significant but were not found to be independent predictors.展开更多
Objective:To investigate the clinical efficacy of metoprolol succinate extended-release tablets in the treatment of post-myocardial infarction ventricular arrhythmias.Methods:The clinical data of 84 patients with post...Objective:To investigate the clinical efficacy of metoprolol succinate extended-release tablets in the treatment of post-myocardial infarction ventricular arrhythmias.Methods:The clinical data of 84 patients with post-myocardial infarction ventricular arrhythmia included in the study were collected and they were divided into Groups A and B with 42 cases each using the randomization method.Group A was treated with oral glucosamine hydrochloride,while Group B was administered oral metoprolol succinate extended-release tablets.Combined indicators were used to evaluate the improvement of clinical indicators,therapeutic effects,and the incidence of adverse reactions in the two groups.Results:The baseline data of the two groups of patients were not statistically significant(Pall>0.05);after treatment,the QT dispersion,corrected QT dispersion,and heart rate of Group B were lower than that of Group A(Pall=0.000<0.001);the 2 total clinical effectiveness of Group B was 95.24%,which was significantly higher than 80.95%in Group A(χ=4.087,P=0.043<0.05);the total incidence of adverse reactions in Group B was 4.76%,which was significantly lower than 219.04%in Group A(χ=4.087,P=0.043<0.05).Conclusion:In the treatment of post-myocardial infarction ventricular arrhythmia,the use of metoprolol succinate extended-release tablets can effectively correct the QT dispersion of patients,improve their heart rate,increase clinical effectiveness,and reduce the incidence of adverse reactions.展开更多
Objective: To explore the effect and mechanism of angiotensin II receptor blockers-Irbesartan on occurrence of ventricular arrhythmias in rats with myocardial ischemia. Methods: Rats with embryonic cardiomyocytes-H9c2...Objective: To explore the effect and mechanism of angiotensin II receptor blockers-Irbesartan on occurrence of ventricular arrhythmias in rats with myocardial ischemia. Methods: Rats with embryonic cardiomyocytes-H9c2 were randomly divided into control group. ischemia group. Irbesartan group and Irbesartan+ischemia group. The cell viability of rats in each group was tested using MTT. Real-time PCR was employed to detect the expression of connexin43 (Cx43) mRNA and western blot to detect the expression of Cx43 and phosphorylated Cx43. SD rats were randomly divided into the sham-operation group (SO). myocardial infarction group (MI). Irbesartan group and MI+ Irbesartan group, with 10 rats in each group. HE staining was employed to observe the change in the pathomorpholouy of left ventricular tissue and TUNEL method to analyze the cell apoptosis in the tissue. The immunofluorescence was adopted to observe the expression and distribution of Cx43 in the left ventricular myocardium and study the change in the expression of Cx43 in the cardiac muscular tissue at mRNA and protein level. Results: The intervention of lrbesartan in the condition of ischemia indicated the significant decrease in the number of necrotic cells. The expression of Cx43 was significantly decreased under the culture of ischemia (P<0.05), but in the presence of Irbesartan, the expression of Cx43 was increased compared with the ischemia group (p<0.01). The results of WB assay showed the similar trend of change at mRNA level. There was the significant difference in the score of ventricular arerythmia between MI group and SO group (P<0.01). The incidence of ventricular tachycardia or ventricular fibrillation was significantly increased compared with the one in SO group (P<0.05). There was the significant difference in the overall score between MI+Irbesartan group and MI group (P<0.05). The expression of Cx43 in the cardiac muscular tissue in MI group was significantly decreased (P<0.01(US) SO group). But the expression of Cx43 was increased after the treatment with Irbesartan. Conclusions: Irbesartan can inhibit the injury of H9c2 cardiomyocytes and the decreased expression of Cx43 that are induced by the ischemic myocardial infarction. Irbesartan can also improve the reconstruction of Cx43 in rats with ischemic myocardium to inhibit the myocardial infarction-induced arrhythmias.展开更多
This work is aimed at exploring the clinical efficacy of continuous positive airway pressuie(CPAP)in treatment of patients with arrhythmias combined with obstructive sleep apnea(OSA).Through evaluating serum native th...This work is aimed at exploring the clinical efficacy of continuous positive airway pressuie(CPAP)in treatment of patients with arrhythmias combined with obstructive sleep apnea(OSA).Through evaluating serum native thiol,malonaldehyde(MDA)and nicotinamide adenine dinucleotide phosphate oxidase(NADPH oxidase)in these patients and describing the effects on oxidative parameters of CPAP therapy for 3 months,we confirmed the impact of oxidative stress on arrhythmias.A total of 64 patients with OSA combined with arrhythmias were collected from April 2014 to April 2017 with full clinical information.Patients were divided into two groups(paired experiment design):32 patients in group A(control group),who received unchanged anti-arrhythmia treatment and 32 patients in group B,who were subjected to unchanged pharmacological anti-arrhythmia therapy combined with CPAP.OSA related parameters were compared between the two groups after 3-month therapy.And the levels of parameters of oxidative stress in patients were measured before and after CPAP therapy.After 3 months of CPAP therapy,compared with the control group,the percentage of sage N3(NREM 3)and stage R(REM)in total sleep time was significantly increased,while apnea-hypopnea index(AHI)and the Epworth Sleepiness Scale(ESS)score were evidently decreased.Meanwhile,the lowest oxygen saturation(LSpCh)was also elevated after CPAP treatment for 3 months.The CPAP therapy significantly prevented the occurrence of arrhythmias(P<0.05).Both the MDA level and NADPH oxidase levels were significantly lower in the group B than in the group A(P<0.05).But serum native thiol was improved by CPAP treatment(P<0.05).In conclusion,proper use of CPAP therapy provides significant benefits for the treatment of arrhythmia in patients with OSA.展开更多
Objective To investigate whether C-reactive protein (CRP) is a biomarker of malignant ventricular arrhythmias (MVA) occurring in non-ST elevation myocardial infarction (NSTEMI) patients with Global Registry of Acute C...Objective To investigate whether C-reactive protein (CRP) is a biomarker of malignant ventricular arrhythmias (MVA) occurring in non-ST elevation myocardial infarction (NSTEMI) patients with Global Registry of Acute Coronary events (GRACE) scores < 140. Methods A total of 1450 NSTEMI patients were included in this study. Hs-CRP blood levels were measured via a turbidimetric immunoassay after confirming the diagnosis of NSTEMI with GRACE scores < 140. Results Consistent with prior studies, the MVA occurrence rate in our cohort was 6.7%, and patients with MVA exhibited a reduced left ventricular ejection fraction (46.1%± 6.9% vs. 61.5%± 8.7%, P = 0.032), a higher incidence of Killip classification > 1 (34.1% vs. 24.2%, P < 0.001), an increased surgical revascularization rate (34.1% vs. 9.7%, P < 0.001), and increased mortality (16.5% vs. 5.8%, P < 0.001). Serum hs-CRP levels were higher (P = 0.003) in NSTEMI patients with MVA, and this increase appeared unrelated to other clinical parameters. The C-statistic to discriminate MVA was 0.82 (95% CI: 0.74–0.89). Using receiver operating characteristics analysis, we optimized a cutoff point of 16 mL/L, and the sensitivity and specificity were 95% and 61%, respectively;the positive predictive value was 20% and the negative predictive value was 99%. Conclusions An hs-CRP assay is a potential MVA biomarker in low-risk NSTEMI patients with GRACE scores < 140. If validated in prospective studies, hs-CRP may offer a low-cost supplementary strategy for risk stratification for NSTEMI patients.展开更多
Objective To evaluate the PR to RR interval ratio (PR/RR,heart rate-adjusted PR) as a prognostic marker for long-term ventricular arrhythmias and cardiac death in patients with implantable cardioverter defibrillator (...Objective To evaluate the PR to RR interval ratio (PR/RR,heart rate-adjusted PR) as a prognostic marker for long-term ventricular arrhythmias and cardiac death in patients with implantable cardioverter defibrillator (ICDs) and cardiac resynchronization therapy with defibrillators (CRT-D).Methods We retrospectively analyzed data from 428 patients who had an ICD/CRT-D equipped with home monitoring.Baseline PR and RR interval data prior to ICD/CRT-D implantation were collected from standard 12-lead electrocardiograph,and the PR/RR was calculated.The primary endpoint was appropriate ICD/CRT-D treatment of ventricular arrhythmias (VAs),and the secondary endpoint was cardiac death.Results During a mean follow-up period of 38.8 ± 10.6 months,197 patients (46%) experienced VAs,and 47 patients (11%) experienced cardiac death.The overall PR interval was 160 ± 40 ms,and the RR interval was 866 ± 124 ms.Based on the receiver operating characteristic curve,a cut-off value of 18.5% for the PR/RR was identified to predict VAs.A PR/RR ≥ 18.5% was associated with an increased risk of VAs [hazard ratio (HR)= 2.243,95% confidence interval (CI)= 1.665–3.022,P < 0.001) and cardiac death (HR = 2.358,95%CI = 1.240–4.483,P = 0.009) in an unadjusted analysis.After adjustment in a multivariate Cox model,the relationship remained significant among PR/RR ≥ 18.5%,VAs (HR = 2.230,95%CI = 1.555–2.825,P < 0.001) and cardiac death (HR = 2.105,95%CI = 1.101–4.025,P = 0.024.Conclusions A PR/RR ≥ 18.5% at baseline can serve as a predictor of future VAs and cardiac death in ICD/CRT-D recipients.展开更多
Cardiac Arrhythmias shows a condition of abnor-mal electrical activity in the heart which is a threat to humans. This paper presents a method to analyze electrocardiogram (ECG) signal, extract the fea-tures, for the c...Cardiac Arrhythmias shows a condition of abnor-mal electrical activity in the heart which is a threat to humans. This paper presents a method to analyze electrocardiogram (ECG) signal, extract the fea-tures, for the classification of heart beats according to different arrhythmias. Data were obtained from 40 records of the MIT-BIH arrhythmia database (only one lead). Cardiac arrhythmias which are found are Tachycardia, Bradycardia, Supraventricular Tachycardia, Incomplete Bundle Branch Block, Bundle Branch Block, Ventricular Tachycardia. A learning dataset for the neural network was obtained from a twenty records set which were manually classified using MIT-BIH Arrhythmia Database Directory and docu- mentation, taking advantage of the professional experience of a cardiologist. Fast Fourier transforms are used to identify the peaks in the ECG signal and then Neural Networks are applied to identify the diseases. Levenberg Marquardt Back-Propagation algorithm is used to train the network. The results obtained have better efficiency then the previously proposed methods.展开更多
In March 2020,the WHO defined the diffusion of novel coronavirus,Severe Acute Respiratory Syndrome-Coronavirus-2(SARS-CoV-2)as pandemic.[1-3]As a consequence,the Italian Government among others has enforced quarantine...In March 2020,the WHO defined the diffusion of novel coronavirus,Severe Acute Respiratory Syndrome-Coronavirus-2(SARS-CoV-2)as pandemic.[1-3]As a consequence,the Italian Government among others has enforced quarantine on the population to contain the diffusion of the infection.Quarantine refers to the separation of communities who have been exposed to an infectious disease.[1-3]Elderly people's lives have been drastically affected by the lockdown and the fear related to the disease’s potential effects and transmission.Fear of contracting COVID-19 is on the rise due to the death toll and alarming news reports in the media.[2,3].展开更多
Fetal arrhythmias reach up around 10%of the total third-level perinatal cardiology references.Sustained bradycardia is defined as a baseline fetal heart rate(FHR)of less than 110 bpm sustained for at least 10 min.The ...Fetal arrhythmias reach up around 10%of the total third-level perinatal cardiology references.Sustained bradycardia is defined as a baseline fetal heart rate(FHR)of less than 110 bpm sustained for at least 10 min.The overall incidence of malignant fetal bradyarrhythmias,such as complete atrioventricular block(AVB)and channellopathies,is relatively rare,1:5000 pregnancies,but represents a serious emergency for the gynecologist,neonatologists,and pediatric cardiologists.Fetal complete AVB is strongly associated with maternal connective tissue disease,but it can be also associated with congenital heart disease and usually with a poorer prognosis with high risk of fetal hydrops and abortion.Currently,the treatment of severe fetal bradyarrhythmias is principally pharmacological and aims to increase the FHR,besides an early resolution of underlying causes,when possible,and a promptly management of fetal heart failure.Intrauterine electrostimulation nowadays is an experimental pioneering method,reserved for limited selected cases.展开更多
Objective The exact biological mechanism whereby exposure to ambient ozone(O3)may contribute to clinical onset of cardiovascular events remains unclear.In this study,we aim to examine the impacts of O3 exposure on car...Objective The exact biological mechanism whereby exposure to ambient ozone(O3)may contribute to clinical onset of cardiovascular events remains unclear.In this study,we aim to examine the impacts of O3 exposure on cardiac arrhythmias and potential pathways involved through autonomic dysfunction and myocardial injury.Methods Seventy-three non-smoking healthy adults were followed with 4 repeated measurements of 24-hour ambulatory arrhythmias,heart rate variability,ST-segment deviation,and blood pressure(BP)in Beijing,China,2014‒2016.Generalized additive mixed models coupled with distributed lag nonlinear models were constructed to evaluate the associations and potential interlinks between O3 exposure and outcome measurements.Results During the study period,24-hour average concentrations of ambient O3 were 47.4µg/m3(ranging from 1.0 to 165.9µg/m3).Increased risks of premature ventricular contraction and ventricular tachycardia were associated with interquartile range increases in O3 exposure during the last 5 days before each participant's clinic visit,with relative risks of 2.14(95%confidence interval[CI]:1.95 to 2.32)and 5.47(95%CI:3.51 to 7.43),respectively.Mediation analyses further showed that sympathetic activation,parasympathetic inhibition,and elevated BP levels,as well as heightened risks of ST-segment depression could mediate up to 47.74%of the risks of arrhythmias attributable to O3 exposure.Conclusion Our results suggest that short-term exposure to ambient O3 could prompt the genesis of arrhythmias partially through worsening autonomic function and myocardial burden.展开更多
Amiodarone is used worldwide to treat cardiac arrhythmias, as well as highly symptomatic cases of atrial fibrillation. With this expanded use, especially following its 1985 United States Food and Drug Administration a...Amiodarone is used worldwide to treat cardiac arrhythmias, as well as highly symptomatic cases of atrial fibrillation. With this expanded use, especially following its 1985 United States Food and Drug Administration approval, and its use as a long-term therapy in common practice, reports of cancers temporarily related to amiodarone have begun to increase. Animal studies, several clinical trials, numerous case reports, and a population-based cohort study have suggested that cancers may be associated with amiodarone use. This review focuses on the ever increasing evidence in the literature that suggests amiodarone therapy, especially with long-term use, may increase the potential risk of cancer development. It also expresses the need for more definitive studies to be conducted to provide clinicians with a clear answer to this important question.展开更多
A canine model of ischemic ventricular tachyarrhythmias was established in open-chest dogs subjected to programmed electrical stimulation (PES) for 5 ̄8 days after acute myocardial infarction. The electrophysiologic e...A canine model of ischemic ventricular tachyarrhythmias was established in open-chest dogs subjected to programmed electrical stimulation (PES) for 5 ̄8 days after acute myocardial infarction. The electrophysiologic effects of sophoridine (Sop) and procainamide (PA) were observed in this canine model. With routine methods of PES, ventricular tachycardia (VT) and ventricular fibrilation (VF) could be reproducibly initiated in this model. Both drugs distinctly lengthened the QTc interval ( P <0.01) and the effective refractory period (ERP) in normal and ischemic ventricular myocardium ( P <0.01), decreased the dispersion of ERP in ischemic myocardium and the dispersion of ERP in left ventricle (P <0.05), and increased the diastolic excitability threshold of normal and ischemic ventricular myocardium remarkably ( P <0.01). Both drugs effectively prevented the PES-induced VT or VF and ischemia-induced VF ( P <0.05). The results indicated that this canine model is a good and reliable one, sophoridine and procainamide may be effective in preventing the onset of reentrant ventricular tachyarrhythmias after myocardial ischemic damage.展开更多
Prophylactic effect of magnesium sulfate on reperfusion arrhythmias was studiedusing a left anterior descending coronary artery occlusion followed by reperfusion in theisolated rat heart.In the first studies,we have o...Prophylactic effect of magnesium sulfate on reperfusion arrhythmias was studiedusing a left anterior descending coronary artery occlusion followed by reperfusion in theisolated rat heart.In the first studies,we have observed a bell-shaped relationship be-tween the incidence of reperfusion-induced ventricular fibrillation(VF)and the durationof preceding ischemia.With 5,10,15,20 and 25 min of ischemia,10,70,60,50 and 20per cent of the hearts exhibited irreversible VF,respectively.In the second studies(10 minischemia),perfusate magnesium sulfate was increased to 3.6,4.8 and 6.0 mmol/L 1 min be-fore coronary ligation,VF fell in a dose-dependent manner from its control total inci-dence of 100%(1.2mmol/L MgSO<sub>4</sub>)to 82%,73% and 18%(P【0.01),respectively.Heartrate was also reduced in a dose-dependent manner,falling from its control value of326±11 to 227±22 beats/min with the highest concentration of magnesium sulfate.Asperfusate magnesium sulfate was increased to 6.0 mmol/L just before reperfusion,no an-ti-arrhythmic effects were observed.With an anti-arrhythmic concentration of magnesiumsulfate(6.0 mmol/L,increased 1 min before ligation),calcium concentration was increasedby 1.5 mmol/L at the same time,under these conditions the anti-arrhythmic effect of mag-nesium sulfate was lost and its negative chronotropic effect was also partially abolished.We conclude that magnesium sulfate has a certain prophylactic effect againstreperfusion induced arrhythmias and this could be due to a direct or indirect calci-um-antagonist action.展开更多
Sudden cardiac death related to athletic competition is a rare but tragic event.The victims are typically young with no previous cardiovascular symptoms or limitations.The majority of sudden cardiac death events in at...Sudden cardiac death related to athletic competition is a rare but tragic event.The victims are typically young with no previous cardiovascular symptoms or limitations.The majority of sudden cardiac death events in athletes are due to ventricular arrhythmias as a result of underlying molecular and/or structural level pathologic substrate.In this article,we will review the physiologic cardiac adaptations to exercise along with arrhythmias seen in athletes with a focus on those commonly associated with sudden cardiac death.展开更多
Effect of berberine on reperfusion arrhythmias was studied using a10min left anterior descending coronary artery occlusion followed by reperfusionin the isolated rat heart.Berberine when given 10min before coronary li...Effect of berberine on reperfusion arrhythmias was studied using a10min left anterior descending coronary artery occlusion followed by reperfusionin the isolated rat heart.Berberine when given 10min before coronary ligation re-duced the incidence of reperfusion arrhythmias in a dose-dependent manner.With10<sup>-5</sup>,3.16×10<sup>-5</sup> and 10<sup>-4</sup>mol/L of berberine,ventricular fibrillation was reducedfrom its control incidence of 100% to 90%,70% and 40% (P【0.05) respectively.Heart rate was also reduced in a dose-dependent manner,falling from its controlvalue of 282±11 to 180±11 beats/min with the highest concentration of berberine.Coronary flow was increased in all berberine treated groups.With anantiarrhythmic dose of berberine (10<sup>-4</sup>mol/L),hearts were paced (5 Hz) duringischemia period;under these conditions the anti-arrhythmic effect of berberinewas lost.When berberine (3.16×10<sup>-5</sup> and 10<sup>-4</sup>mol/L) was administered just beforereperfusion,no anti-arrhythmic effects were observed.The α-adrenoceptor antago-nist phentolamine (2.6×10<sup>-5</sup>mol/L) prevented reperfusion arrhythmias and ismuch more effective than berberine.These results suggest that the prophylatic ef-fects of berberine on reperfusion arrhythmias in the isolated rat heart are due toits negative chronotropic properties.展开更多
Crdiovascular diseases (CVD) incur a heavy burden of morbidity and mortality among patients with chronic kidney disease (CKD),particularly among the elderly.It is estimated that about 22-25% of all adults beyond the a...Crdiovascular diseases (CVD) incur a heavy burden of morbidity and mortality among patients with chronic kidney disease (CKD),particularly among the elderly.It is estimated that about 22-25% of all adults beyond the age of 65 years have moderate or severe renal dysfunction.1。展开更多
Sleep is essential to the normal psychological and physiological activities of the human body.Increasing evidence indicates that sleep deprivation is associated with the occurrence,development,and poor treatment effec...Sleep is essential to the normal psychological and physiological activities of the human body.Increasing evidence indicates that sleep deprivation is associated with the occurrence,development,and poor treatment effects of various arrhythmias.Sleep deprivation affects not only the peripheral nervous system but also the central nervous system,which regulates the occurrence of arrhythmias.In addition,sleep deprivation is associated with apoptotic pathways,mitochondrial energy metabolism disorders,and immune system dysfunction.Although studies increasingly suggest that pathological sleep patterns are associated with various atrial and ventricular arrhythmias,further research is needed to identify specific mechanisms and recommend therapeutic interventions.This review summarizes the findings of sleep deprivation in animal experiments and clinical studies,current challenges,and future research directions in the field of arrhythmias.展开更多
文摘In healthcare,the persistent challenge of arrhythmias,a leading cause of global mortality,has sparked extensive research into the automation of detection using machine learning(ML)algorithms.However,traditional ML and AutoML approaches have revealed their limitations,notably regarding feature generalization and automation efficiency.This glaring research gap has motivated the development of AutoRhythmAI,an innovative solution that integrates both machine and deep learning to revolutionize the diagnosis of arrhythmias.Our approach encompasses two distinct pipelines tailored for binary-class and multi-class arrhythmia detection,effectively bridging the gap between data preprocessing and model selection.To validate our system,we have rigorously tested AutoRhythmAI using a multimodal dataset,surpassing the accuracy achieved using a single dataset and underscoring the robustness of our methodology.In the first pipeline,we employ signal filtering and ML algorithms for preprocessing,followed by data balancing and split for training.The second pipeline is dedicated to feature extraction and classification,utilizing deep learning models.Notably,we introduce the‘RRI-convoluted trans-former model’as a novel addition for binary-class arrhythmias.An ensemble-based approach then amalgamates all models,considering their respective weights,resulting in an optimal model pipeline.In our study,the VGGRes Model achieved impressive results in multi-class arrhythmia detection,with an accuracy of 97.39%and firm performance in precision(82.13%),recall(31.91%),and F1-score(82.61%).In the binary-class task,the proposed model achieved an outstanding accuracy of 96.60%.These results highlight the effectiveness of our approach in improving arrhythmia detection,with notably high accuracy and well-balanced performance metrics.
文摘This editorial,comments on the article by Spartalis et al published in the recent issue of the World Journal of Cardiology.We here provide an outlook on potential ethical concerns related to the future application of gene therapy in the field of inherited arrhythmias.As monogenic diseases with no or few therapeutic options available through standard care,inherited arrhythmias are ideal candidates to gene therapy in their treatment.Patients with inherited arrhythmias typically have a poor quality of life,especially young people engaged in agonistic sports.While genome editing for treatment of inherited arrhythmias still has theoretical application,advances in CRISPR/Cas9 technology now allows the generation of knock-in animal models of the disease.However,clinical translation is somehow expected soon and this make consistent discussing about ethical concerns related to gene editing in inherited arrhythmias.Genomic off-target activity is a known technical issue,but its relationship with ethnical and individual genetical diversity raises concerns about an equitable accessibility.Meanwhile,the costeffectiveness may further limit an equal distribution of gene therapies.The economic burden of gene therapies on healthcare systems is is increasingly recognized as a pressing concern.A growing body of studies are reporting uncertainty in payback periods with intuitive short-term effects for insurance-based healthcare systems,but potential concerns for universal healthcare systems in the long term as well.Altogether,those aspects strongly indicate a need of regulatory entities to manage those issues.
基金supported by the research project—Application of Machine Learning Methods for Early Diagnosis of Pathologies of the Cardiovascular System funded by the Ministry of Science and Higher Education of the Republic of Kazakhstan.Grant No.IRN AP13068289.
文摘This research introduces an innovative ensemble approach,combining Deep Residual Networks(ResNets)and Bidirectional Gated Recurrent Units(BiGRU),augmented with an Attention Mechanism,for the classification of heart arrhythmias.The escalating prevalence of cardiovascular diseases necessitates advanced diagnostic tools to enhance accuracy and efficiency.The model leverages the deep hierarchical feature extraction capabilities of ResNets,which are adept at identifying intricate patterns within electrocardiogram(ECG)data,while BiGRU layers capture the temporal dynamics essential for understanding the sequential nature of ECG signals.The integration of an Attention Mechanism refines the model’s focus on critical segments of ECG data,ensuring a nuanced analysis that highlights the most informative features for arrhythmia classification.Evaluated on a comprehensive dataset of 12-lead ECG recordings,our ensemble model demonstrates superior performance in distinguishing between various types of arrhythmias,with an accuracy of 98.4%,a precision of 98.1%,a recall of 98%,and an F-score of 98%.This novel combination of convolutional and recurrent neural networks,supplemented by attention-driven mechanisms,advances automated ECG analysis,contributing significantly to healthcare’s machine learning applications and presenting a step forward in developing non-invasive,efficient,and reliable tools for early diagnosis and management of heart diseases.
基金Supported by the Sixth Affiliated Hospital of Sun Yat-sen University Clinical Research-1010 Program,No.1010PY(2023)-06the National Nature Science Foundation of China,No.81400301+1 种基金the Fundamental Research Funds for the Central Universities,No.19ykpy10Guangzhou Health Science and Technology Project,No.20231A010068.
文摘BACKGROUND Individuals diagnosed with gastrointestinal tumors are at an increased risk of developing cardiovascular diseases.Among which,ventricular arrhythmia is a prevalent clinical concern.This suggests that ventricular arrhythmias may have predictive value in the prognosis of patients with gastrointestinal tumors.AIM To explore the prognostic value of ventricular arrhythmias in patients with gastrointestinal tumors receiving surgery.METHODS We retrospectively analyzed data from 130 patients undergoing gastrointestinal tumor resection.These patients were evaluated by a 24-h ambulatory electrocardiogram(ECG)at the Sixth Affiliated Hospital of Sun Yat-sen University from January 2018 to June 2020.Additionally,41 general healthy age-matched and sexmatched controls were included.Patients were categorized into survival and non-survival groups.The primary endpoint was all-cause mortality,and secondary endpoints included major adverse cardiovascular events(MACEs).RESULTS Colorectal tumors comprised 90%of cases.Preoperative ambulatory ECG monitoring revealed that among the 130 patients with gastrointestinal tumors,100(76.92%)exhibited varying degrees of premature ventricular contractions(PVCs).Ten patients(7.69%)manifested non-sustained ventricular tachycardia(NSVT).The patients with gastrointestinal tumors exhibited higher PVCs compared to the healthy controls on both conventional ECG[27(21.3)vs 1(2.5),P=0.012]and 24-h ambulatory ECG[14(1.0,405)vs 1(0,6.5),P<0.001].Non-survivors had a higher PVC count than survivors[150.50(7.25,1690.50)vs 9(0,229.25),P=0.020].During the follow-up period,24 patients died and 11 patients experienced MACEs.Univariate analysis linked PVC>35/24 h to all-cause mortality,and NSVT was associated with MACE.However,neither PVC burden nor NSVT independently predicted outcomes according to multivariate analysis.CONCLUSION Patients with gastrointestinal tumors exhibited elevated PVCs.PVCs>35/24 h and NSVT detected by 24-h ambulatory ECG were prognostically significant but were not found to be independent predictors.
文摘Objective:To investigate the clinical efficacy of metoprolol succinate extended-release tablets in the treatment of post-myocardial infarction ventricular arrhythmias.Methods:The clinical data of 84 patients with post-myocardial infarction ventricular arrhythmia included in the study were collected and they were divided into Groups A and B with 42 cases each using the randomization method.Group A was treated with oral glucosamine hydrochloride,while Group B was administered oral metoprolol succinate extended-release tablets.Combined indicators were used to evaluate the improvement of clinical indicators,therapeutic effects,and the incidence of adverse reactions in the two groups.Results:The baseline data of the two groups of patients were not statistically significant(Pall>0.05);after treatment,the QT dispersion,corrected QT dispersion,and heart rate of Group B were lower than that of Group A(Pall=0.000<0.001);the 2 total clinical effectiveness of Group B was 95.24%,which was significantly higher than 80.95%in Group A(χ=4.087,P=0.043<0.05);the total incidence of adverse reactions in Group B was 4.76%,which was significantly lower than 219.04%in Group A(χ=4.087,P=0.043<0.05).Conclusion:In the treatment of post-myocardial infarction ventricular arrhythmia,the use of metoprolol succinate extended-release tablets can effectively correct the QT dispersion of patients,improve their heart rate,increase clinical effectiveness,and reduce the incidence of adverse reactions.
基金supported by Research Topic of Department of Health of Jiangxi Province(No.20131074)Natural Science Fund of Jiangxi Province(No:20122BAB205028)
文摘Objective: To explore the effect and mechanism of angiotensin II receptor blockers-Irbesartan on occurrence of ventricular arrhythmias in rats with myocardial ischemia. Methods: Rats with embryonic cardiomyocytes-H9c2 were randomly divided into control group. ischemia group. Irbesartan group and Irbesartan+ischemia group. The cell viability of rats in each group was tested using MTT. Real-time PCR was employed to detect the expression of connexin43 (Cx43) mRNA and western blot to detect the expression of Cx43 and phosphorylated Cx43. SD rats were randomly divided into the sham-operation group (SO). myocardial infarction group (MI). Irbesartan group and MI+ Irbesartan group, with 10 rats in each group. HE staining was employed to observe the change in the pathomorpholouy of left ventricular tissue and TUNEL method to analyze the cell apoptosis in the tissue. The immunofluorescence was adopted to observe the expression and distribution of Cx43 in the left ventricular myocardium and study the change in the expression of Cx43 in the cardiac muscular tissue at mRNA and protein level. Results: The intervention of lrbesartan in the condition of ischemia indicated the significant decrease in the number of necrotic cells. The expression of Cx43 was significantly decreased under the culture of ischemia (P<0.05), but in the presence of Irbesartan, the expression of Cx43 was increased compared with the ischemia group (p<0.01). The results of WB assay showed the similar trend of change at mRNA level. There was the significant difference in the score of ventricular arerythmia between MI group and SO group (P<0.01). The incidence of ventricular tachycardia or ventricular fibrillation was significantly increased compared with the one in SO group (P<0.05). There was the significant difference in the overall score between MI+Irbesartan group and MI group (P<0.05). The expression of Cx43 in the cardiac muscular tissue in MI group was significantly decreased (P<0.01(US) SO group). But the expression of Cx43 was increased after the treatment with Irbesartan. Conclusions: Irbesartan can inhibit the injury of H9c2 cardiomyocytes and the decreased expression of Cx43 that are induced by the ischemic myocardial infarction. Irbesartan can also improve the reconstruction of Cx43 in rats with ischemic myocardium to inhibit the myocardial infarction-induced arrhythmias.
文摘This work is aimed at exploring the clinical efficacy of continuous positive airway pressuie(CPAP)in treatment of patients with arrhythmias combined with obstructive sleep apnea(OSA).Through evaluating serum native thiol,malonaldehyde(MDA)and nicotinamide adenine dinucleotide phosphate oxidase(NADPH oxidase)in these patients and describing the effects on oxidative parameters of CPAP therapy for 3 months,we confirmed the impact of oxidative stress on arrhythmias.A total of 64 patients with OSA combined with arrhythmias were collected from April 2014 to April 2017 with full clinical information.Patients were divided into two groups(paired experiment design):32 patients in group A(control group),who received unchanged anti-arrhythmia treatment and 32 patients in group B,who were subjected to unchanged pharmacological anti-arrhythmia therapy combined with CPAP.OSA related parameters were compared between the two groups after 3-month therapy.And the levels of parameters of oxidative stress in patients were measured before and after CPAP therapy.After 3 months of CPAP therapy,compared with the control group,the percentage of sage N3(NREM 3)and stage R(REM)in total sleep time was significantly increased,while apnea-hypopnea index(AHI)and the Epworth Sleepiness Scale(ESS)score were evidently decreased.Meanwhile,the lowest oxygen saturation(LSpCh)was also elevated after CPAP treatment for 3 months.The CPAP therapy significantly prevented the occurrence of arrhythmias(P<0.05).Both the MDA level and NADPH oxidase levels were significantly lower in the group B than in the group A(P<0.05).But serum native thiol was improved by CPAP treatment(P<0.05).In conclusion,proper use of CPAP therapy provides significant benefits for the treatment of arrhythmia in patients with OSA.
基金supported by the Capital Health Research and Development of Special Foundation (2018-1-2061)
文摘Objective To investigate whether C-reactive protein (CRP) is a biomarker of malignant ventricular arrhythmias (MVA) occurring in non-ST elevation myocardial infarction (NSTEMI) patients with Global Registry of Acute Coronary events (GRACE) scores < 140. Methods A total of 1450 NSTEMI patients were included in this study. Hs-CRP blood levels were measured via a turbidimetric immunoassay after confirming the diagnosis of NSTEMI with GRACE scores < 140. Results Consistent with prior studies, the MVA occurrence rate in our cohort was 6.7%, and patients with MVA exhibited a reduced left ventricular ejection fraction (46.1%± 6.9% vs. 61.5%± 8.7%, P = 0.032), a higher incidence of Killip classification > 1 (34.1% vs. 24.2%, P < 0.001), an increased surgical revascularization rate (34.1% vs. 9.7%, P < 0.001), and increased mortality (16.5% vs. 5.8%, P < 0.001). Serum hs-CRP levels were higher (P = 0.003) in NSTEMI patients with MVA, and this increase appeared unrelated to other clinical parameters. The C-statistic to discriminate MVA was 0.82 (95% CI: 0.74–0.89). Using receiver operating characteristics analysis, we optimized a cutoff point of 16 mL/L, and the sensitivity and specificity were 95% and 61%, respectively;the positive predictive value was 20% and the negative predictive value was 99%. Conclusions An hs-CRP assay is a potential MVA biomarker in low-risk NSTEMI patients with GRACE scores < 140. If validated in prospective studies, hs-CRP may offer a low-cost supplementary strategy for risk stratification for NSTEMI patients.
文摘Objective To evaluate the PR to RR interval ratio (PR/RR,heart rate-adjusted PR) as a prognostic marker for long-term ventricular arrhythmias and cardiac death in patients with implantable cardioverter defibrillator (ICDs) and cardiac resynchronization therapy with defibrillators (CRT-D).Methods We retrospectively analyzed data from 428 patients who had an ICD/CRT-D equipped with home monitoring.Baseline PR and RR interval data prior to ICD/CRT-D implantation were collected from standard 12-lead electrocardiograph,and the PR/RR was calculated.The primary endpoint was appropriate ICD/CRT-D treatment of ventricular arrhythmias (VAs),and the secondary endpoint was cardiac death.Results During a mean follow-up period of 38.8 ± 10.6 months,197 patients (46%) experienced VAs,and 47 patients (11%) experienced cardiac death.The overall PR interval was 160 ± 40 ms,and the RR interval was 866 ± 124 ms.Based on the receiver operating characteristic curve,a cut-off value of 18.5% for the PR/RR was identified to predict VAs.A PR/RR ≥ 18.5% was associated with an increased risk of VAs [hazard ratio (HR)= 2.243,95% confidence interval (CI)= 1.665–3.022,P < 0.001) and cardiac death (HR = 2.358,95%CI = 1.240–4.483,P = 0.009) in an unadjusted analysis.After adjustment in a multivariate Cox model,the relationship remained significant among PR/RR ≥ 18.5%,VAs (HR = 2.230,95%CI = 1.555–2.825,P < 0.001) and cardiac death (HR = 2.105,95%CI = 1.101–4.025,P = 0.024.Conclusions A PR/RR ≥ 18.5% at baseline can serve as a predictor of future VAs and cardiac death in ICD/CRT-D recipients.
文摘Cardiac Arrhythmias shows a condition of abnor-mal electrical activity in the heart which is a threat to humans. This paper presents a method to analyze electrocardiogram (ECG) signal, extract the fea-tures, for the classification of heart beats according to different arrhythmias. Data were obtained from 40 records of the MIT-BIH arrhythmia database (only one lead). Cardiac arrhythmias which are found are Tachycardia, Bradycardia, Supraventricular Tachycardia, Incomplete Bundle Branch Block, Bundle Branch Block, Ventricular Tachycardia. A learning dataset for the neural network was obtained from a twenty records set which were manually classified using MIT-BIH Arrhythmia Database Directory and docu- mentation, taking advantage of the professional experience of a cardiologist. Fast Fourier transforms are used to identify the peaks in the ECG signal and then Neural Networks are applied to identify the diseases. Levenberg Marquardt Back-Propagation algorithm is used to train the network. The results obtained have better efficiency then the previously proposed methods.
文摘In March 2020,the WHO defined the diffusion of novel coronavirus,Severe Acute Respiratory Syndrome-Coronavirus-2(SARS-CoV-2)as pandemic.[1-3]As a consequence,the Italian Government among others has enforced quarantine on the population to contain the diffusion of the infection.Quarantine refers to the separation of communities who have been exposed to an infectious disease.[1-3]Elderly people's lives have been drastically affected by the lockdown and the fear related to the disease’s potential effects and transmission.Fear of contracting COVID-19 is on the rise due to the death toll and alarming news reports in the media.[2,3].
文摘Fetal arrhythmias reach up around 10%of the total third-level perinatal cardiology references.Sustained bradycardia is defined as a baseline fetal heart rate(FHR)of less than 110 bpm sustained for at least 10 min.The overall incidence of malignant fetal bradyarrhythmias,such as complete atrioventricular block(AVB)and channellopathies,is relatively rare,1:5000 pregnancies,but represents a serious emergency for the gynecologist,neonatologists,and pediatric cardiologists.Fetal complete AVB is strongly associated with maternal connective tissue disease,but it can be also associated with congenital heart disease and usually with a poorer prognosis with high risk of fetal hydrops and abortion.Currently,the treatment of severe fetal bradyarrhythmias is principally pharmacological and aims to increase the FHR,besides an early resolution of underlying causes,when possible,and a promptly management of fetal heart failure.Intrauterine electrostimulation nowadays is an experimental pioneering method,reserved for limited selected cases.
基金This work was supported by China Postdoctoral Science Foundation(2021M690249)Michigan Medicine-PKUHSC Joint Institute for Translational and Clinical Research(BMU20140467).
文摘Objective The exact biological mechanism whereby exposure to ambient ozone(O3)may contribute to clinical onset of cardiovascular events remains unclear.In this study,we aim to examine the impacts of O3 exposure on cardiac arrhythmias and potential pathways involved through autonomic dysfunction and myocardial injury.Methods Seventy-three non-smoking healthy adults were followed with 4 repeated measurements of 24-hour ambulatory arrhythmias,heart rate variability,ST-segment deviation,and blood pressure(BP)in Beijing,China,2014‒2016.Generalized additive mixed models coupled with distributed lag nonlinear models were constructed to evaluate the associations and potential interlinks between O3 exposure and outcome measurements.Results During the study period,24-hour average concentrations of ambient O3 were 47.4µg/m3(ranging from 1.0 to 165.9µg/m3).Increased risks of premature ventricular contraction and ventricular tachycardia were associated with interquartile range increases in O3 exposure during the last 5 days before each participant's clinic visit,with relative risks of 2.14(95%confidence interval[CI]:1.95 to 2.32)and 5.47(95%CI:3.51 to 7.43),respectively.Mediation analyses further showed that sympathetic activation,parasympathetic inhibition,and elevated BP levels,as well as heightened risks of ST-segment depression could mediate up to 47.74%of the risks of arrhythmias attributable to O3 exposure.Conclusion Our results suggest that short-term exposure to ambient O3 could prompt the genesis of arrhythmias partially through worsening autonomic function and myocardial burden.
文摘Amiodarone is used worldwide to treat cardiac arrhythmias, as well as highly symptomatic cases of atrial fibrillation. With this expanded use, especially following its 1985 United States Food and Drug Administration approval, and its use as a long-term therapy in common practice, reports of cancers temporarily related to amiodarone have begun to increase. Animal studies, several clinical trials, numerous case reports, and a population-based cohort study have suggested that cancers may be associated with amiodarone use. This review focuses on the ever increasing evidence in the literature that suggests amiodarone therapy, especially with long-term use, may increase the potential risk of cancer development. It also expresses the need for more definitive studies to be conducted to provide clinicians with a clear answer to this important question.
文摘A canine model of ischemic ventricular tachyarrhythmias was established in open-chest dogs subjected to programmed electrical stimulation (PES) for 5 ̄8 days after acute myocardial infarction. The electrophysiologic effects of sophoridine (Sop) and procainamide (PA) were observed in this canine model. With routine methods of PES, ventricular tachycardia (VT) and ventricular fibrilation (VF) could be reproducibly initiated in this model. Both drugs distinctly lengthened the QTc interval ( P <0.01) and the effective refractory period (ERP) in normal and ischemic ventricular myocardium ( P <0.01), decreased the dispersion of ERP in ischemic myocardium and the dispersion of ERP in left ventricle (P <0.05), and increased the diastolic excitability threshold of normal and ischemic ventricular myocardium remarkably ( P <0.01). Both drugs effectively prevented the PES-induced VT or VF and ischemia-induced VF ( P <0.05). The results indicated that this canine model is a good and reliable one, sophoridine and procainamide may be effective in preventing the onset of reentrant ventricular tachyarrhythmias after myocardial ischemic damage.
文摘Prophylactic effect of magnesium sulfate on reperfusion arrhythmias was studiedusing a left anterior descending coronary artery occlusion followed by reperfusion in theisolated rat heart.In the first studies,we have observed a bell-shaped relationship be-tween the incidence of reperfusion-induced ventricular fibrillation(VF)and the durationof preceding ischemia.With 5,10,15,20 and 25 min of ischemia,10,70,60,50 and 20per cent of the hearts exhibited irreversible VF,respectively.In the second studies(10 minischemia),perfusate magnesium sulfate was increased to 3.6,4.8 and 6.0 mmol/L 1 min be-fore coronary ligation,VF fell in a dose-dependent manner from its control total inci-dence of 100%(1.2mmol/L MgSO<sub>4</sub>)to 82%,73% and 18%(P【0.01),respectively.Heartrate was also reduced in a dose-dependent manner,falling from its control value of326±11 to 227±22 beats/min with the highest concentration of magnesium sulfate.Asperfusate magnesium sulfate was increased to 6.0 mmol/L just before reperfusion,no an-ti-arrhythmic effects were observed.With an anti-arrhythmic concentration of magnesiumsulfate(6.0 mmol/L,increased 1 min before ligation),calcium concentration was increasedby 1.5 mmol/L at the same time,under these conditions the anti-arrhythmic effect of mag-nesium sulfate was lost and its negative chronotropic effect was also partially abolished.We conclude that magnesium sulfate has a certain prophylactic effect againstreperfusion induced arrhythmias and this could be due to a direct or indirect calci-um-antagonist action.
文摘Sudden cardiac death related to athletic competition is a rare but tragic event.The victims are typically young with no previous cardiovascular symptoms or limitations.The majority of sudden cardiac death events in athletes are due to ventricular arrhythmias as a result of underlying molecular and/or structural level pathologic substrate.In this article,we will review the physiologic cardiac adaptations to exercise along with arrhythmias seen in athletes with a focus on those commonly associated with sudden cardiac death.
文摘Effect of berberine on reperfusion arrhythmias was studied using a10min left anterior descending coronary artery occlusion followed by reperfusionin the isolated rat heart.Berberine when given 10min before coronary ligation re-duced the incidence of reperfusion arrhythmias in a dose-dependent manner.With10<sup>-5</sup>,3.16×10<sup>-5</sup> and 10<sup>-4</sup>mol/L of berberine,ventricular fibrillation was reducedfrom its control incidence of 100% to 90%,70% and 40% (P【0.05) respectively.Heart rate was also reduced in a dose-dependent manner,falling from its controlvalue of 282±11 to 180±11 beats/min with the highest concentration of berberine.Coronary flow was increased in all berberine treated groups.With anantiarrhythmic dose of berberine (10<sup>-4</sup>mol/L),hearts were paced (5 Hz) duringischemia period;under these conditions the anti-arrhythmic effect of berberinewas lost.When berberine (3.16×10<sup>-5</sup> and 10<sup>-4</sup>mol/L) was administered just beforereperfusion,no anti-arrhythmic effects were observed.The α-adrenoceptor antago-nist phentolamine (2.6×10<sup>-5</sup>mol/L) prevented reperfusion arrhythmias and ismuch more effective than berberine.These results suggest that the prophylatic ef-fects of berberine on reperfusion arrhythmias in the isolated rat heart are due toits negative chronotropic properties.
文摘Crdiovascular diseases (CVD) incur a heavy burden of morbidity and mortality among patients with chronic kidney disease (CKD),particularly among the elderly.It is estimated that about 22-25% of all adults beyond the age of 65 years have moderate or severe renal dysfunction.1。
文摘Sleep is essential to the normal psychological and physiological activities of the human body.Increasing evidence indicates that sleep deprivation is associated with the occurrence,development,and poor treatment effects of various arrhythmias.Sleep deprivation affects not only the peripheral nervous system but also the central nervous system,which regulates the occurrence of arrhythmias.In addition,sleep deprivation is associated with apoptotic pathways,mitochondrial energy metabolism disorders,and immune system dysfunction.Although studies increasingly suggest that pathological sleep patterns are associated with various atrial and ventricular arrhythmias,further research is needed to identify specific mechanisms and recommend therapeutic interventions.This review summarizes the findings of sleep deprivation in animal experiments and clinical studies,current challenges,and future research directions in the field of arrhythmias.