Beta-blocker use and risk of symptomatic bradyarrhythmias： a hospital-based case-control study

Objective To investigate the risk factors of symptomatic bradyarrhythrnias in relation to β-blockers use. Methods A hospital-based case-control study [228 patients： 108 with symptomatic bradyarrhythmias （cases） and 120 controls] was conducted in Sultanah Aminah Hospital, Malaysia between January 2011 and January 2014. Results The mean age was 61.1 ~ 13.3 years with a majority of men （68.9%）. Cases were likely than control to be older, hypertensive, lower body mass index and concomitant use of rate-controlling drugs （such as digoxin, verapamil, diltiazem, ivabradine or amiodarone）. Significantly higher level of serum potassium, urea, creatinine and lower level of estimated glomerular filtration rate （eGFR） were observed among cases as compared to controls. On univariate analysis among patients on β-blockers, older age （crude OR： 1.07; 95% CI： 1.03-1.11, P = 0.000）, hypertension （crude OR： 5.6; 95% CI： 1.51-20.72, P = 0.010）, lower sodium （crude OR： 0.04; 95% CI： 0.81-0.99, P = 0.036）, higher potassium （crude OR： 2.36; 95% CI： 1.31-4.26, P = 0.004） and higher urea （crude OR： 1.23; 95% CI： 1.11-1.38, P = 0.000） were associated with increased risk of symptomatic bradyarrhythmias; eGFR was inversely and significantly associated with symptomatic bradyarrhythmias in both ＇β-blockers＇ （crude OR： 0.97; 95% CI： 0.964）.98, P = 0.000） and ＇non-β-blockers＇ （crude OR： 0.99; 95% CI： 0.97-0.99, P = 0.023） arms. However, eGFR was not significantly associated with symptomatic bradyarrhythmias in the final model of both ＇β-blockers＇ （adjusted OR： 0.98; 95% CI： 0.96-0.98, P = 0.103） and ＇non-p-blockers＇ （adjusted OR： 0.99; 95% CI： 0.97-1.01, P = 0.328） arms. Importantly, older age was a significant predictor of symptomatic bradyarrhythmias in the ＇β-blockers＇ as compared to the ＇non-β-blockers＇ arms （adjusted OR： 1.09; 95% CI： 1.03-1.15, P = 0.003 vs. adjusted OR： 1.03; 95% CI： 0.98-1.09, P = 0.232, respectively）. Conclusion Older age was a significant predictor of symptomatic bradyarrhythmias in patients on β-blockers than those without β-blockers.

Study of Bradyarrhythmias in Acute Myocardial Infarction

Background: Arrhythmias after acute myocardial infarction are common. Bradyarrhythmias need specific insight into when and how to treat them. Objectives: To delineate the incidence, course, and management of different types of bradyarrhythmias after acute myocardial infarction, the study period was five years. Methods: 453 patients with Acute Myocardial Infarction (AMI) were admitted to intensive care in five years. ECGs were analyzed for the presence of bradyarrhythmias and details of management. Results: 65 patients with bradycardia were found. Sinus bradycardia in 40, sick sinus syndrome in 10, junctional rhythm in 10, second-degree block in 10, complete heart block in 24. We divided patients with sinus bradycardia into a stable group and an unstable group. Unstable sinus bradycardia is more prevalent in cases with hypotension or shock, slower heart rates, gross or transmural infarction. Also, predictors of instability were changeable morphology of the “P” wave and inferior rather than anterior infarction. The indications and danger of atropine are defined. Complete heart block was found in 24 patients (0.053%). 13 were managed by drug therapy (isoprenaline, corticosteroids, and atropine);Eleven patients were paced. 14 out of the 24 patients died (58%), the total mortality rate among the 453 patients was 22%. The prognostic factors of CHB were defined. Techniques of introduction of the lead in RV without fluoroscopy are described. Conclusions: Sinus bradycardia in AMI is accompanied by a lower incidence of mortality. Atropine is not a safe drug to be given as routine. Complete heart block predictors of mortality are the association with heart failure, early-onset, and persistence of the block.

Fetal Bradyarrhythmias:Etiopathogenesis,Diagnosis and Treatment:Between Literature Review and Experience of a Tertiary Center

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.

Impact of chronic kidney disease on mortality in older adults treated with pacemaker implantation

Objective To investigate whether chronic kidney disease could negatively impact survival in older adults needing pacemaker implantation after admission for bradyarrhythmias. Methods This retrospective observational study considered 538 older adults consecutively admitted, who had been followed-up for 31 ± 20 months. Subjects with poor short-term prognosis were excluded. Charlson comorbidity index （CCI） and estimated glomerular filtration rate （eGFR） was calculated, along with the independent relationship between all-cause mortality and clinical data. Hazard Ratio （HR） was calculated by Cox regression analysis. Results Mean age of the population was 85 ± 3.7 years, and causes for implantation were atrioventricular block in 51.9% and other bradyarrhythmias in 48.1% of cases. Mean eGFR was 58.3 ± 24 mL/min per 1.73 m2, and mean CCI was 3.65 ± 2.28. Death for all-causes was recorded in 213 subjects. Deceased patients were older, had lower eGFR, higher comorbidity, higher prevalence of myocardial infarction, congestive heart failure, cerebrovascular disease, dementia and chronic pulmonary disease. Age （HR： 1.081, 95% CI： 1.044-1.119; P 〈 001）, CCI （HR： 1.651, 95% CI： 1.286-2.121, P 〈 001） and eGFR 〈 45 mL/min per 1.73 m2 （HR： 1.360, 95% CI： 1.024-1.806; P = 0.033） were predictors of death. Conclusions Renal dysftmction, as well as comorbidity, impacts negatively survival of older adults treated with pacemaker implantation because of bradyarrhythmias.

Bradyarrythmias: A Study of Anthropometric, Demographic and Comorbidity Profiles in an African Population

Background: Bradyarrhythmias are a group of cardiac rhythm disorders that are characterized by bradycardia and they are cosmopolitan in distribution. Their demographic, anthropometric and comorbidity attributes are yet to be clearly established in Africa. Aims and Objectives: This study was conducted to determine the anthropometric, demographic and comorbidity factors in an African population. Methods: We got data from two groups of patients—Group A were bradyarrhythmia patients who already had permanent pacemaker insertion (PPI). Group B were non-cardiac non-debilitated patients of similar age bracket. The sample population consisted of referrals received via clinics, admission through the emergency centres and wards. Their bio-data, hospital identification numbers, ages and gender and other relevant parameters were carefully documented. The ensuing data was analyzed with SPSS 21 statistical software. Results: There were 31 patients in group A (17 male and 14 female patients) and 36 in group B (22 male and 14 female patients). They were all above 20 years of age. Group A had a mean age of 65.8 ± 4.76 years while group B had a mean age of 62.2 ± 4.47 years. Body Mass Index (BMI ≥ 25 Kg·m-2), elevated BP, and diabetes mellitus were important clinical attributes of bradyarrhythmias in the studied group. Discussion and Conclusion: Our study showed that the stated anthropometric, demographic and comorbidity parameters are important attributes for bradyarrhythmias in African population.

Berberine behind the thriller of marked symptomatic bradycardia

Berberine is used in traditional Chinese medicine for the treatment of congestive heart failure, hypertension, diabetes, and dyslipidaemia and has a good safety profile. We report a case of a 53-year-old sportsman referred to our hospital for the onset of fatigue and dyspnoea upon exertion after he started berberine to treat hypercholesterolaemia. An electrocardiogram showed sinus bradycardia (45 bpm), first-degree atrioventricular block, and competitive junctional rhythm. An ergometric stress test showed slightly reduced chronotropic competence and the presence of runs of competitive junctional rhythm, atrial tachycardia, and sinus pauses in the recovery. After 10 d of wash-out from berberine, the patient experienced a complete resolution of symptoms, and an ergometric stress test showed good chronotropic competence. An electrocardiogram Holtershowed a latent hypervagotonic state. This is the first case report that shows that berberine could present certain side effects in hypervagotonic people, even in the absence of a situation that could cause drug accumulation. Therefore, berberine's use should be carefully weighed in hypervagotonic people due to the drug's bradycardic and antiarrhythmic properties, which could became proarrhythmic, exposing patients to potential health risks.

Arrhythmogenic epilepsy and pacing need: A matter of controversy

There is increasing awareness among the cardiology community regarding ictal bradyarrhythmias as a cause of loss of consciousness. A high degree of suspicion is necessary when diagnosing ictal bradyarrhythmias, and delay in diagnosing this condition may lead to morbidity associated with falls and trauma. Ictal bradyarrhythmias have also been suggested to be associated with sudden unexplained death in epilepsy, although evidence related to this association is limited. There is no guidelinedirected therapy for symptomatic ictal bradyarrhythmias due to a lack of randomized, controlled trials. Cardiac pacemaker therapy is commonly used for these patients; however, currently, there is no universal agreement on the pacing indications for these patients. In this review, we focus on the pathophysiology and clinical presentation of ictal bradyarrhythmias and then discuss the pacing need based on the available literature data.

Temporary pacemaker protected transjugular intrahepatic portosystemic shunt in a patient with acute variceal bleeding and bradyarrhythmia:A case report

BACKGROUND Esophagogastric varices are a common complication of cirrhosis with portal hypertension and endoscopic treatment has been recognized as a primary preventive and therapeutic option for such patients;however,it should be noted that bradyarrhythmia is regarded as one of the contraindications to endoscopic examination.Meanwhile,acute variceal bleeding may result in a high mortality rate in cirrhotic patients with portal hypertension accompanied by bradyarrhythmia.At present,there is an absence of reports concerning the treatment of such group of patients who underwent transjugular intrahepatic portosystemic shunt(TIPS).The present report details the case of a cirrhotic patient with acute variceal bleeding accompanied by bradyarrhythmia who underwent TIPS under temporary pacemaker protection.CASE SUMMARY We report the case of a 64-year-old male patient who was confirmed with bradyarrhythmia by ambulatory electrocardiogram 24 h before the operation.The patient was successfully treated by TIPS under temporary pacemaker protection.CONCLUSION In terms of cirrhotic patients with abnormal cardiac electrophysiological conduction,TIPS may be effective in reducing the complications of portal hypertension following the exclusion of severe pulmonary hypertension and heart failure,showing moderate feasibility in clinical applications.

Prevalence of sleep-disordered breathing in elderly patients with cardiac pacemaker: a case-control study

Objective To investigate the prevalence of sleep-disordered breathing in elderly patients with permanent cardiac pacemaker implantation due to bradyarrhythmias, and the relationship between pacing mode and patients' sleep apnea-hypopnea index.Methods Forty-four elderly patients (＞60 years) with cardiac pacemaker and their 44 controls matched for gender, age, body mass index and cardiovascular morbidity were studied using polysomnography or portable sleep monitoring device. Results Prevalence of sleep-disordered breathing (apnea-hypopnea index ≥5/h) was 44.7% and the mean apnea-hypopnea index was 8.2 ±4.1/h in the cardiac pacemaker group, which were significantly higher than those in control subjects (25% and 4.6±2.4/h, respectively, P＜0.01 and P＜0.05). The mean apnea-hypopnea index of patients with DDD or AAI pacemaker was significantly lower than that of patients with VVI pacemaker. Conclusions Sleep-disordered breathing was more common in patients who had their cardiac pacemaker implanted due to bradyarrhythmias than in their matched controls. Compared with VVI pacing, DDD or AAI pacing may be more beneficial to patients with bradyarrhythmias and sleep-disordered breathing.

Relationship among intermittent pulse,regularly intermittent pulse,and bradyarrhythmia

Pulse diagnosis is an important basis for the diagnosis of Chinese medicine.It is the rich experience accumulated by the predecessors in the long and continuous practice,and it is a unique diagnosis method of Chinese medicine.There are many names of pulse conditions in traditional Chinese medicine.The four elements are analyzed and summarized in terms of position,number,shape,and momentum.The four elements are used as 28 kinds of pulses.Among them,the regularly intermittent pulse and the intermittent pulse are characterized by arrhythmia and intermittent stop of the pulse.Intermittent pulse means irregular intervals;when a pulse comes,Regularly Intermittent pulse have regular stops.This kind of phenomenon is similar to the bradyarrhythmia in modern medicine.The knot pulse is an irregular pulse stopping,which can be seen clinically in sinus arrest,second-degree type I sinus block,second-degree type I atrioventricular block,and escape beats and so on.On the other hand,Regularly Intermittent pulse is a regular pulse stopping,which can be clinically found in the second degree type II sinus block,the second degree type II sinus block,and the second degree type I atrioventricular block with a special 2:1 type of atrioventricular block type and so on.

Evaluation of Safety and Efficacy of Qinming8631 DR Implantable Cardiac Pacemaker in Chinese Patients： A Prospective, Multicenter, Randomized Controlled Trial of the First Domestically Developed Pacemaker of China

Background：High cost of imported pacemakers is a main obstacle for Chinese patients suffering from bradyarrhythmia,and a domestically developed pacemaker will help lower the burden.This study aimed to evaluate the safety and efficacy ofQinming8631 DR （Qinming Medical,Baoji,China）,the first domestically developed dual-chamber pacemaker of China,compared with a commercially available pacemaker Talos DR （Biotronik,Berlin,Germany） in Chinese patients.Methods：A prospective randomized trial was conducted at 14 centers in China.Participants were randomized into trial （Qinming8631 DR） and control （Talos DR） groups.Parameters of the pacing systems were collected immediately after device implantation and during follow-ups.The effective pacing rate at 6-month follow-up was recorded as the primary end point.Electrical properties,magnet response,single-and double-pole polarity conversion,rate response function,and adverse events of the pacing system were analyzed.The Cochran-Mantel-Haenszel Chi-square test,paired t-test,and Wilcoxon signed-rank test were used for measuring primary qualitative outcomes and comparing normally and abnormally distributed measurement data.Results：A total of 225 patients with a diagnosis ofbradyarrhythmia and eligible for this study were randomly enrolled into the trial （n =113） and control （n =112） groups.They underwent successful pacemaker implantation with acceptable postoperative pacing threshold and sensitivity.Effective pacing rates of trial and control groups were comparable both in the full analysis set and the per protocol set （81.4% vs.79.5%,P =0.712 and 95.4% vs.89.5%,P =0.143,respectively）.In both data sets,noninferiority of the trial group was above the predefined noninferiority limit（-9.5%）.Conclusions：This study established the noninferiority ofQinming8631 DR to Talos DR.The safety and efficacy ofQinming8631 DR pacemaker were comparable to those of Talos DR in treating patients with cardiac bradyarrhythmia.