The prevalence and prognosis of third-degree atrioventricular conduction block: the Reykjavik study

The impact of smoking on third-degree atrioventricular block outcomes: A propensity-matched analysis

Background

Third-degree atrioventricular (AV) blocks are rare but cause significant symptoms and require immediate intervention. Coronary artery disease (CAD) is felt to be the most common etiology. Although smoking is a prominent risk factor for CAD, there is a paucity of data assessing the direct effect of smoking on third-degree AV block.

Methods

We performed a retrospective cohort study on adult-weighted admissions in 2019-2020 with a primary diagnosis of third-degree AV block and a history of smoking using the National Inpatient Sample (NIS) database. In-hospital mortality, rates of pacemaker insertion, cardiogenic shock, cardiac arrest, acute kidney injury (AKI), stroke, tracheal intubation, mechanical ventilation, mechanical circulatory support, vasopressor use, length of stay (LOS), and total hospitalization costs were analyzed using regression analysis. We performed a secondary analysis using propensity score matching to confirm the results.

Results

A total of 77,650 admissions met inclusion criteria (33,625 females [43.3 %], 58,315. Caucasians [75 %], 7030 African American [9 %], 6155 Hispanic [7.9 %]; mean [SD] age 75.4.[10.2] years) before propensity matching. A total of 29,380 (37.8 %) patients with AV block were smokers.A total of 5560 patients with and without a history of smoking were matched for the analysis. Smokers had.decreased odds of mortality (aOR, 0.59; CI, 0.44-0.78; p < 0.001), cardiogenic shock, cardiac arrest, tracheal intubation, mechanical ventilation, shorter LOS, and lower total hospital costs in both the multivariable regression and propensity-matched analyses.

Conclusion

Third-degree AV block had lower in-hospital mortality, cardiogenic shock, cardiac arrest, LOS, and total hospitalization cost in patients with smoking history.

Disruption of the endothelial glycocalyx layer is associated with idiopathic complete atrioventricular block in the elderly population: An observational pilot study

Idiopathic atrioventricular block (iCAVB) is the most common reason for the need for a permanent pacemaker in the elderly population. The fibrotic process that occurs in the conduction system of the heart with aging is the main pathogenesis in the development of iCAVB. However, the processes that trigger the development of iCAVB in the elderly population have not been fully elucidated. In this study, we aimed to reveal the possible relationship between the endothelial glycocalyx (EG) layer and idiopathic complete atrioventricular block. A group of 68 consecutive patients who developed iCAVB and a group of 68 healthy subjects matched for age, sex, and cardiovascular risk factors were included in the study. The groups were compared for clinical, laboratory, and levels of Syndecan-1 (SDC1), an EG layer marker. In the study, SDC1 levels were found to be significantly higher in the iCAVB group compared to the control group (23.7 ± 7.5 vs 16.7 ± 5.2; p = 0.009). In multivariable regression analysis, SDC1 was determined as an independent potential predictor for iCAVB (OR: 1.200; 95% CI: 1.119-1.287; p < 0.001). In the receiver operating characteristic curve analysis, SDC1 predicted iCAVB with 74% sensitivity and 72% specificity at the best cut-off value of 18.5 ng/mL (area under the curve: 0.777; confidence interval: 0.698-0.856; p < 0.001). Disruption of the endothelial glycolic layer may be one of the main triggering factors for the process leading to iCAVB.

Exploring the prevalence of undetected bradyarrhythmia in dementia with Lewy bodies

PURPOSE

To explore the prevalence of undetected bradyarrhythmia in a cohort of people with dementia with Lewy bodies.

METHODS

Thirty participants diagnosed with dementia with Lewy bodies were enrolled from three memory clinics in southern Sweden between May 2021 and November 2022. None had a history of high-grade atrioventricular block or sick sinus syndrome. Each participant underwent orthostatic testing, cardiac [123I]metaiodobenzylguanidine scintigraphy and 24-h ambulatory electrocardiographic monitoring. Concluding bradyarrhythmia diagnosis was obtained until the end of December 2022.

RESULTS

Thirteen participants (46.4%) had bradycardia at rest during orthostatic testing and four had an average heart rate < 60 beats per minute during ambulatory electrocardiographic monitoring. Three participants (10.7%) received a diagnosis of sick sinus syndrome, of whom two received pacemaker implants to manage associated symptoms. None received a diagnosis of second- or third-degree atrioventricular block.

CONCLUSION

This report showed a high prevalence of sick sinus syndrome in a clinical cohort of people with dementia with Lewy bodies. Further research on the causes and consequences of sick sinus syndrome in dementia with Lewy bodies is thus warranted.

Management of Complete Heart Block in a Pregnant Woman with Systemic Lupus Erythematosus-Associated Complications: Treatment Considerations and Pitfalls

We present a case of a pregnant woman with systemic lupus erythematosus (SLE) who was diagnosed with asymptomatic complete heart block (CHB) during pregnancy. To evaluate possible risks and benefits of pacemaker (PM) implantation, a multidisciplinary counselling board was held. Its recommendation was to perform PM implantation to prevent intra-uterine growth restriction from insufficient cardiac output using a fluoroscopic protective shield. The procedure was performed without complications and established permanent pacing on onwards ECG examinations. The patient subsequently gave birth to a healthy newborn. After a retrospective clinical case evaluation and review of relevant literature, a presumptive association between CHB and the primary diagnosis was proposed. Above that, pregnant women with SLE who develop hypertension are commonly treated with methyldopa, which may cause conduction abnormalities. Clinical recommendations for young female patients expecting pregnancy are lacking in this area. Careful diagnostic and treatment approaches should be used in the management of possible SLE-related complications in women of child-bearing age, focusing on preventable events.

Pathological and Comprehensive Genetic Investigation of Autopsy Cases of Idiopathic Bradyarrhythmia

BACKGROUND

Idiopathic bradyarrhythmia is considered to be due to pathological degeneration of the cardiac conduction system (CCS) during aging. There appears to have been no comprehensive genetic investigations in patients with idiopathic bradyarrhythmia.Methods and Results: Ten autopsy cases with advanced bradyarrhythmia (6 men and 4 women; age: 70-94 years, 81.5±6.9 years; 5 cases each of sinus node dysfunction [SND] and complete atrioventricular block [CAVB]) were genetically investigated by using whole-exome sequencing. Morphometric analysis of the CCS was performed with sex-, age- and comorbidity-matched control cases. As a result, severe loss of nodal cells and distal atrioventricular conduction system were found in SND and CAVB, respectively. However, the conduction tissue loss was not significant in either the atrioventricular node or the proximal bundle of His in CAVB cases. A total of 13 heterozygous potential variants were found in 3 CAVB and 2 SND cases. Of these 13 variants, 4 were missense in the known progressive cardiac conduction disease-related genes: GATA4 and RYR2. In the remaining 9 variants, 5 were loss-of-function mutation with highly possible pathogenicity.

CONCLUSIONS

In addition to degenerative changes of selectively vulnerable areas in the heart during advancing age, the vulnerability of the CCS, which may be associated with "rare variants of small effect," may also be a contributing factor to the degeneration of CCS, leading to "idiopathic" bradyarrhythmia.

Sex differences in rates of permanent pacemaker implantation and in-hospital complications: A statewide cohort study of over 7 million persons from 2009–2018

Background

Whether a bias exists in the implantation of permanent pacemakers (PPI) and complications according to sex and age in the Australian population is unclear.

Hypothesis

Population rate of PPI and its complications differed between men and women.

Methods

We examined the prevalence of PPI from January-2009 to December-2018 from datasets held by the New South Wales (NSW) Centre-for-Health-Record-Linkage, including patient’s characteristics and in-hospital complications. All analysis was stratified by sex and age by decade.

Results

A total of 28,714 admissions involved PPI (40% women). The mean PPI rate (±standard-deviation) and median age (interquartile range) was 2,871±242 per-annum and 80yrs (73-86yrs), respectively. At the same time-period, the mean NSW population size was 7,487,393±315,505 persons (50% women; n = 3,773,756±334,912). The mean annual age-adjusted rate of PPI was 125.5±11.6 per-100,000-men, compared to 63.4±14.3 per-100,000-women (P<0.01). The mean annual rate of PPI increased from 2009–2017 by 0.9±3.3% in men, compared to 0.4±4.4% in women (P<0.01) suggesting a widening disparity. Total non-fatal in-hospital complications was higher in women compared to men (8.2% vs 6.6%, P<0.01), and this persisted throughout study period even after adjusting for multiple covariates. Overall, in-hospital mortality was low (0.73%) and similar between sexes.

Conclusion

In a statewide Australian population exceeding 7 million, PPI rates were consistently nearly two-fold higher for men compared to women over 10-years, with an apparently widening disparity, that was not explained by age. Overall complication rates were higher in women. Future studies should examine the aetiology behind this disparity in PPI rates, as well as its complications.

Heart Disease and Stroke Statistics-2022 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2022 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population and an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, and the global burden of cardiovascular disease and healthy life expectancy.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Prevalence and risk factors of atrioventricular block among 15 million Chinese health examination participants in 2018: a nation-wide cross-sectional study

Background

Nationwide data on the prevalence of atrioventricular (AV) block are currently unavailable in China. Thus, we aimed to assess the prevalence and risk factors of AV block among Chinese health examination adults.

Methods

A total of 15,181,402 participants aged ≥ 18 years (mean age 41.5 ± 13.4 years, 53.2% men) who underwent an electrocardiogram as a part of routine health examination in 2018 were analyzed. AV block was diagnosed by physicians using 12-lead electrocardiogram. Overall and stratified prevalence (by age, sex, and city size) of all, first-, second- and third-degree AV block were calculated. Multivariable logistic regression analyses were performed to explore risk factors associated with AV block.

Results

AV block was observed in 88,842 participants, including 86,153 with first-degree, 2249 with second-degree and 440 with third-degree AV block. The age- and sex-standardized prevalence rate [95% confidence interval (CI)] of all, first-, second- and third-degree AV block were 7.06‰ (7.01–7.11), 6.84‰ (6.79–6.89), 0.18‰ (0.17–0.18) and 0.04‰ (0.03–0.04) respectively. After multivariable adjustment, the risk of AV block was positively associated with older age, being male, lower heart rate, higher body mass index, hypertension, diabetes and low high-density lipoprotein cholesterol. High total cholesterol was associated with a lower risk of AV block.

Conclusion

First-degree AV block is relatively common while severe AV block is rare in health examination adults. Besides, AV block was highly prevalent among the elderly. The risk of AV block was associated with older age, being male and metabolic factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02105-3.

Heart Disease and Stroke Statistics-2021 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2021 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, an enhanced focus on social determinants of health, adverse pregnancy outcomes, vascular contributions to brain health, the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors related to cardiovascular disease.

RESULTS

Each of the 27 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

A case report of one vasovagal syncope patient with third-degree atrioventricular block caused by SCN5A gene mutation and literature review

BACKGROUND

Vasovagal syncope (VVS) is common in children and significantly affects their quality of life. To our knowledge, this the first case report of SCN5A gene mutation associated with VVS and third-degree atrioventricular block (atrioventricular block, AVB), which could help pediatricians aware that VVS is not always a benign condition and help to identify VVS children at the risk of sudden death.

CASE PRESENTATION

A twelve-year-old male child was admitted to Beijing Children's Hospital of Capital Medical University for chest tightness for 9 days and syncope in July 2018. The child was diagnosed as VVS with third-degree AVB after complete investagations. A heterozygous mutation in the exon coding region of the SCN5A gene, C. 5851G > T (coding region 5551 nucleotide changed from G to T), was detected in the peripheral blood of the child. Electrophysiological examination and modified vagal ganglion radiofrequency ablation were performed in the child. The ECG playback was normal on the second day after operation. Holter showed no abnormality and no chest tightness or syncope occurred after 3 months and 1 year follow-up.

CONCLUSIONS

Our case report firstly reported that SCN5A mutation contributed to the pathogenesis of VVS with third-degree AVB. Vagal ganglion modified ablation have obtained good therapeutic effect. Gene analysis was of great value to the accurate diagnosis and treatment of VVS children.

Heart Disease and Stroke Statistics-2020 Update: A Report From the American Heart Association

BACKGROUND

The American Heart Association, in conjunction with the National Institutes of Health, annually reports on the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, diet, and weight) and health factors (cholesterol, blood pressure, and glucose control) that contribute to cardiovascular health. The Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, congenital heart disease, rhythm disorders, subclinical atherosclerosis, coronary heart disease, heart failure, valvular disease, venous disease, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The American Heart Association, through its Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States to provide the most current information available in the annual Statistical Update. The 2020 Statistical Update is the product of a full year's worth of effort by dedicated volunteer clinicians and scientists, committed government professionals, and American Heart Association staff members. This year's edition includes data on the monitoring and benefits of cardiovascular health in the population, metrics to assess and monitor healthy diets, an enhanced focus on social determinants of health, a focus on the global burden of cardiovascular disease, and further evidence-based approaches to changing behaviors, implementation strategies, and implications of the American Heart Association's 2020 Impact Goals.

RESULTS

Each of the 26 chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policy makers, media professionals, clinicians, healthcare administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Novel missense variant in TTN cosegregating with familial atrioventricular block

BACKGROUND

Cardiovascular diseases are the most common cause of death globally. In which atrioventricular block (AVB) is a common disorder with genetic causes, but the responsible genes have not been fully identified yet. To determine the underlying causative genes involved in cardiac AVB, here we report a three-generation Chinese family with severe autosomal dominant cardiac AVB that has been ruled out as being caused by known genes mutations.

METHODS

Whole-exome sequencing was performed in five affected family members across three generations, and co-segregation analysis was validated on other members of this family.

RESULTS

Whole-exome sequencing and subsequent co-segregation validation identified a novel germline heterozygous point missense mutation, c.49287C > A (p.N16429K), in the titin (TTN, NM_001267550.2) gene in all 5 affected family members but not in the unaffected family members, neither in the large population according to the Genome Aggregation Database (https://gnomad.broadinstitute.org/). The point mutation is predicted to be functionally deleterious by in-silico software tools. Our finding was further supported by the conservative analysis across species.

CONCLUSION

Based on this study, TTN was identified as a potential novel candidate gene for autosomal dominant AVB; this study expands the mutational spectrum of TTN gene and is the first to implicate TTN mutations as AVB disease causing in a Chinese pedigree.

A unique case of bradycardia recognized by wearable technology as first presentation of complete heart block

Wearable technology has advanced significantly, and the proposed health benefits have been widely touted. Most of the discussion has been surrounding the identification and diagnosis of asymptomatic atrial fibrillation. However, the heart monitoring functions of the wearable technology can also identify other abnormalities as well. We present the first case of wearable technology identified bradycardia diagnosed as the primary presentation of complete heart block. Wearable technology has advanced significantly, but still poses questions regarding its use in screening for rare conditions. One remaining challenge is balancing the desire to screen for rare asymptomatic conditions without overburdening emergency departments with patients responding to alarms on their devices.

Occurrence of complete heart block associated with acute renal infarction

Complete heart block (CHB) and acute renal infarction (ARI) are both uncommon diseases and seldom encountered in the clinical practice. We describe a rare case of pre-existing left bundle branch block, presenting simultaneously with CHB and ARI. The possible mechanism depends on prior presence of either CHB or ARI. If ARI occurs first, severe pain and embolism may enhance the vagal tone resulting in decrease in the heart rate and transient intraventricular conduction interruption, which subsequently causes CHB. The opposite scenario, CHB preceding ARI, is also possible. CHB can be physiologic and transient, with higher risk of development in the circumstance of pre-existing conduction system disturbances. Patients with CHB are predisposed to formation of thrombi and thromboemboli, giving rise to ARI. In conclusion, awareness and timely identification of the clinical manifestations of these two diseases may facilitate early diagnosis and prompt management.

Complete Heart Block in a Diabetic Patient with a Preexisting LBBB and Normal Coronaries, Paradoxically Responding to Atropine

We present a case of a complete atrioventricular block (AV block) with different aberrancy patterns during sinus rhythm and escape rhythm. A 66-year-old woman visited our emergency department complaining of sudden onset dizziness and fatigue over the past thirty minutes. Her medical history was remarkable for arterial hypertension, type 2 diabetes mellitus, and hypothyroidism. The patient had a known Left Bundle Branch Block (LBBB) on past ECGs. Upon palpation of peripheral pulse, a measurement of 32 beats per minute was obtained. No other sign of hemodynamic instability was present. A 12-Lead ECG revealed a complete heart block with sparse QRS complexes with a Right Bundle Branch Block (RBBB) morphology. Before the insertion of a temporary transvenous pacemaker, atropine was administered intravenously. Shortly after the administration, the patient's heart rhythm was restored to sinus rhythm (SR) with LBBB. The patient remained hemodynamically stable and in sinus rhythm at the cardiac ICU and was scheduled for implantation of a permanent pacemaker at a specialized tertiary center. Before successful implantation, a coronary angiography revealed normal coronary anatomy with no atherosclerotic lesions.

Takotsubo cardiomyopathy in the setting of complete heart block

Few cases of coincident takotsubo cardiomyopathy and complete heart block (CHB) have been reported. A 62-year-old woman presented with typical chest pain and was found to have CHB with a left ventricular ejection fraction of 35% and apical ballooning on ventriculogram. The patient was transvenously paced and a permanent biventricular pacemaker was placed when the CHB did not resolve. Repeat echocardiography 15 days after the event showed the ejection fraction to be 50%. This case highlights management strategies in this unique situation.

A Rare Case of Complete Heart Block in a Young Patient

Introduction

Complete heart block (CHB) is considered as one of the dangerous rhythms since it can progress to lethal arrhythmias such as ventricular tachycardia. It can be congenital or acquired. Patients may present with frequent palpitations, presyncope, dyspnea, or chest pain but also may remain asymptomatic. Extensive work-up should be conducted to exclude secondary causes such as infections, cardiac ischemia or myopathies, autoimmune diseases, or endocrinological diseases. In our paper, we would like to present a case of CHB in the setting of aortic abdominal thrombus that nearly occluded both renal arteries. The CHB in this case is thought to be caused by hypertensive cardiomyopathy due to ongoing uncontrolled hypertension, which is caused by bilateral renal artery stenosis.

Case Presentation

A 31-year-old male with history of active smoking was incidentally found to have high blood pressure, bradycardia, and CHB on electrocardiogram. The patient was admitted to a cardiology ward and extensive work-up revealed hypokinesia of the left ventricle with low ejection fraction and left ventricle concentric hypertrophy, large abdominal aortic thrombus with bilateral renal artery stenosis, and evidence of arterial collateral connections, which suggest chronicity. The patient then was placed on four antihypertensive medications but eventually, he underwent bilateral renal artery stenting and insertion of permanent pacemaker for his CHB. The patient's blood pressure then was under control with only one medication, and subsequent CT angiogram showed no evidence of stenosis of both renal arteries.

Conclusion

Uncontrolled hypertension can lead to hypertensive cardiomyopathy, which in turn can cause conduction abnormalities such as CHB. Although hypertension can be secondary to a treatable underlying cause, permanent pacemaker is essential to treat CHB.

Position paper for management of elderly patients with pacemakers and implantable cardiac defibrillators: Groupe de Rythmologie et Stimulation Cardiaque de la Société Française de Cardiologie and Société Française de Gériatrie et Gérontologie

Despite the increasingly high rate of implantation of pacemakers (PMs) and implantable cardioverter defibrillators (ICDs) in elderly patients, data supporting their clinical and cost-effectiveness in this age stratum are ambiguous and contradictory. We reviewed the data regarding the applicability, safety and effectiveness of conventional pacing, ICDs and cardiac resynchronization therapy (CRT) in elderly patients. Although periprocedural risk may be slightly higher in the elderly, the implantation procedure for PMs and ICDs is still relatively safe in this age group. In older patients with sinus node disease, the general consensus is that DDD pacing with the programming of an algorithm to minimize ventricular pacing is preferred. In very old patients presenting with intermittent or suspected atrioventricular block, VVI pacing may be appropriate. In terms of correcting potentially life-threatening arrhythmias, the effectiveness of ICD therapy is similar in older and younger individuals. However, the assumption of persistent ICD benefit in the elderly population is questionable, as any advantageous effect of the device on arrhythmic death may be attenuated by higher total non-arrhythmic mortality. While septuagenarians and octogenarians have higher annual all-cause mortality rates, ICD therapy may remain effective in selected patients at high risk of arrhythmic death and with minimum comorbidities despite advanced age. ICD implantation among the elderly, as a group, may not be cost-effective, but the procedure may reach cost-effectiveness in those expected to live more than 5-7years after implantation. Elderly patients usually experience significant functional improvement after CRT, similar to that observed in middle-aged patients. Management of CRT non-responders remains globally the same, while considering a less aggressive approach in terms of reinterventions (revision of left ventricular [LV] lead placement, addition of a right ventricular or LV lead, LV endocardial pacing configuration). Overall, physiological age, general status and comorbidities rather than chronological age per se should be the decisive factors in making a decision about device implantation selection for survival and well-being benefit in elderly patients.

Medium-term effects of septal and apical pacing in pacemaker-dependent patients: a double-blind prospective randomized study

BACKGROUND

Pacing the right ventricle is established practice, but there remains controversy as to the optimal site to preserve hemodynamic function.

AIMS

To evaluate clinical and hemodynamic differences between apical and septal pacing in pacemaker-dependent patients.

METHODS

Patients receiving their first pacemaker for advanced atrioventricular block, with the atria in sinus rhythm, were randomized to receive apical (Group A) or septal (Group S) ventricular leads. After implant, with the device programmed VVI 70 beats/min fixed rate, patients underwent a 6-minute walk test and a transthoracic echocardiogram. Then, DDDR was programmed at nominal settings. The same tests were performed at 6 months and 12 months follow-up. If ventricular pacing was less than 98%, the patient was excluded.

RESULTS

A total of 142 patients were included in the study. During the study year, 71 (50%) were excluded for not fulfilling the condition of 98% ventricular pacing. Groups A and S had 34 and 37 patients, respectively. Age and gender were similar in the groups. At implant, QRS duration was significantly greater in Group A (158 ms) than Group S (146 ms; P = 0.018), and the QRS axis was different: -74.5° in Group A and 1° in Group S (P < 0.001). At 1 year, the 6-minute walk improved significantly in both groups: Group A 15% (P = 0.048) and Group S 24% (P = 0.001). Left ventricular ejection fraction (LVEF) increased from 0.57 to 0.61 (P = 0.008) in Group S, without significant change in Group A.

CONCLUSIONS

After 1 year, pacemaker-dependent patients with septal ventricular leads have better clinical and functional (LVEF) outcome.

Epidemiology of arrhythmias and conduction disorders in older adults

Normal aging is associated with a multitude of changes in the cardiovascular system, including decreased compliance of blood vessels, mild concentric left ventricular hypertrophy, an increased contribution of atrial contraction to left ventricular filling, and a higher incidence of many cardiac arrhythmias, both bradyarrhythmias and tachyarrhythmias. Conduction disorders also become more common with age, and may either be asymptomatic, or cause hemodynamic changes requiring treatment. The epidemiology of common arrhythmias and conduction disorders in the elderly is reviewed.

Temporary third-degree atrioventricular block in a case of apical ballooning syndrome

Apical ballooning is characterized by severe but reversible contractile dysfunction. The causative factor and the pathomechanism remain unknown. Several arrhythmias are reported to occur in apical-ballooning. We present a unique case of a 58-year-old man presenting with apical ballooning complicated by a prolonged third-degree atrioventricular block requiring the implantation of a pacemaker.