Clinical management of arrhythmias in elderly patients: results of the European Heart Rhythm Association survey

Ventricular arrhythmia inducibility in porcine infarct model after stereotactic body radiation therapy

BACKGROUND

Ventricular arrhythmia (VA) is the primary mechanism of sudden death in patients with structural heart disease. Cardiac stereotactic body radiation therapy (SBRT) delivered to the scar in the left ventricle significantly reduces the burden of VA.

OBJECTIVE

The goal of this study was to investigate the impact of SBRT on scar morphology and VA inducibility in a porcine infarct model.

METHODS

Myocardial infarction (MI) was created in 10 Yorkshire pigs involving the left anterior descending artery territory. Cardiac positron emission tomography and computed tomography were performed for targeted SBRT. Alternative pigs received SBRT at 25 Gy in a single fraction. The terminal experiment included endocardial mapping, programmed ventricular stimulation, and tissue harvesting.

RESULTS

Of the 10 pigs infarcted, 2 died prematurely after MI and 8 (4 MI and 4 MI+SBRT) survived. Mean time from MI to SBRT was 48 ± 12 days, and mean time from SBRT to harvest was 32 ± 12 days. Scar was localized on intracardiac mapping in all pigs, and the scar was denser in the MI+SBRT compared with the MI-only group (33% ± 20% vs 14% ± 11%; P = .07). All 4 MI pigs had inducible VA during programmed stimulation, whereas only 1 of 4 pigs had inducible VA in the MI+SBRT arm (100% vs 25%; P = .07). No myocardial fibrosis was seen in the remote areas in either group.

CONCLUSION

SBRT reduced VA inducibility in pigs with scarring after MI. Endocardial mapping revealed denser scar in pigs receiving SBRT compared with those that did not, suggesting that SBRT suppresses VA inducibility through better scar homogenization.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society (HRS), the Asia Pacific HRS, and the Latin American HRS.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society .

Index and Repeat Ablation for Atrial Fibrillation in Older versus Younger Patients: A Propensity-Score Matching Analysis

Catheter ablation is a well-established rhythm control therapy in atrial fibrillation (AF). Although the prevalence of AF increases dramatically with age, the prognosis and safety profile of index and repeat ablation procedures remain unclear in the older population. The primary endpoint of this study was to assess the arrhythmia recurrence, reablation and complication rates in older patients. Secondary endpoints were the identification of independent predictors of arrhythmia recurrence and reablation, including information on pulmonary vein (PV) reconnection and other atrial foci. Older (n=129, ≥70 years) and younger (n=129, <70 years) patients were compared using a propensity-score matching analysis based on age, gender, obesity, hypertension, dyslipidemia, diabetes mellitus, dilated left atrium, severe obstructive sleep apnea, cardiac disease, left systolic ventricular function, AF pattern and ablation technique. Arrhythmia recurrence and reablation were evaluated in both groups using a Cox regression analysis in order to identify predictors. During a 30-month follow-up period, there were no significant differences between older and younger patients in the arrhythmia-free survival (65.1% and 59.7%; log-rank test p=0.403) and complication (10.1% and 10.9%; p>0.999) rates after the index ablation. However, the reablation rate was significantly different (46.7% and 69.2%; p<0.05, respectively). In those patients who underwent reablation procedure (redo subgroups), there were no differences in the incidence of PV reconnection (38.1% redo-older and 27.8% redo-younger patients; p=0.556). However, the redo-older patients had lower reconnected PVs per patient (p<0.01) and lower atrial foci (2.3 and 3.7; p<0.01) than the redo-younger patients. A further important finding was that age was not an independent predictor of arrhythmia recurrence or reablation. Our data reveal that the AF index ablation in older patients had a similar efficacy and safety profile to younger patients. Therefore, age alone must not be considered a prognostic factor for AF ablation but the presence of limiting factors such as frailty and multiple comorbidities.

Impact of age on the prognosis of patients with ventricular tachyarrhythmias and aborted cardiac arrest

BACKGROUND

This study evaluated the prognostic impact of age on patients presenting with ventricular tachyarrhythmias (VTA) and aborted cardiac arrest.

MATERIAL AND METHODS

The present registry-based, monocentric cohort study included all consecutive patients presenting at the University Medical Center Mannheim (UMM) between 2002 and 2016 with ventricular tachycardia (VT), ventricular fibrillation (VF) and aborted cardiac arrest. Middle-aged (40-60 years old) were compared to older patients (> 60 years old). Furthermore, age was analyzed as a continuous variable. The primary endpoint was all-cause mortality at 2.5 years. The secondary endpoints were cardiac death at 24 h, all-cause mortality at index hospitalization, all-cause mortality after index hospitalization and the composite endpoint at 2.5 years of cardiac death at 24 h, recurrent VTA, and appropriate implantable cardioverter defibrillator (ICD) treatment.

RESULTS

A total of 2259 consecutive patients were included (28% middle-aged, 72% older). Older patients were more often associated with all-cause mortality at 2.5 years (27% vs. 50%; hazard ratio, HR = 2.137; 95% confidence interval, CI 1.809-2.523, p = 0.001) and the secondary endpoints. Even patient age as a continuous variable was independently associated with mortality at 2.5 years in all types of VTA. Adverse prognosis in older patients was demonstrated by multivariate Cox regression analyses and propensity score matching. Chronic kidney disease (CKD), systolic left ventricular dysfunction (LVEF) < 35%, cardiopulmonary resuscitation (CPR) and cardiogenic shock worsened the prognosis for both age groups, whereas acute myocardial infarction (STEMI/NSTEMI) and the presence of an ICD improved prognosis.

CONCLUSION

The results of this study suggest that increasing age is associated with increased mortality in VTA patients. Compared to the middle-aged, older patients were associated with higher all-cause mortality at 2.5 years and the secondary endpoints.

Cryoballoon ablation for atrial fibrillation in octogenarians: a propensity score-based analysis with a younger cohort

BACKGROUND

In terms of safety and efficacy, cryoballoon ablation (CB-A) has become a valid option for achieving pulmonary vein isolation (PVI) in patients affected by symptomatic atrial fibrillation. However, CB-A data in octogenarians are still scarce and limited to single-centre experiences. The present multicentre study aimed to compare the outcomes and complications of index CB-A in patients older than 80 years with a cohort of younger patients.

METHODS AND RESULTS

We retrospectively enrolled 97 consecutive patients aged ≥80 years who underwent PVI using the second-generation CB-A. This group was compared with a younger cohort of patients using a 1:1 propensity score matching. After the matching, 70 patients from the elderly group were analysed and compared with 70 younger patients (control group). The mean age was 81.4 ± 1.9 years among octogenarians and 65.2 ± 10.2 years in the younger cohort. The global success rate after a median follow-up of 23 [18-32.5] months was 60.0% in the elderly group and 71.4% in the control group (P = 0.17). Phrenic nerve palsy was the most common complication occurring in a total of 11 patients (7.9%): in 6 (8.6%) patients in the elderly group and in 5 patients (7.1%) in the younger group (P = 0.51). Only two (1.4%) major complications occurred: one (1.4%) femoral artery pseudoaneurysm in the control group, which resolved with a tight groin bandage, and one (1.4%) case of urosepsis in the elderly group. Arrhythmia recurrence during the blanking period and the need for electrical cardioversion to restore sinus rhythm after PVI were found to be the only independent predictors of late arrhythmia relapses.

CONCLUSIONS

The present study showed that CB-A PVI is as feasible, safe and effective among appropriately selected octogenarians as it is in younger patients.

Catheter Ablation for Atrial Fibrillation in the Elderly > 75 Years old: Systematic Review and Meta-Analysis

INTRODUCTION

Atrial fibrillation (AF) ablation is increasingly performed worldwide. As comfort with AF ablation increases, the procedure is increasingly used in patients that are older and in those with more comorbidities. However, it is not well established whether AF ablation in the elderly, especially those >75 years old, has comparable safety and efficacy to younger populations.

OBJECTIVE

To compare the efficacy and safety profiles in patients older than 75years undergoing AF ablation with younger patients.

METHODS

Databases from EMBASE, Medline, PubMed and Cochrane, were searched from inception through September 2021. Studies that compared the success rates in AF catheter ablation and all complications rates between patients who were older vs under 75 years were included. Effect estimates from the individual studies were extracted and combined using random effect, generic inverse variance method of DerSimonian and Laird.

RESULTS

Twenty-seven observational studies were included in the analysis consisting of 363,542 patients who underwent AF ablation. Comparing patients older than 75 years old to younger patients, there was no difference in the success of ablation rates between elderly and younger patients (pooled OR 0.85: 95% CI:0.69 - 1.05, p=0.131). On the other hand, AF ablation in the elderly was associated with higher complication rates (pooled OR 1.43: 95% CI:1.21 - 1.68, p<0.001) CONCLUSION: As AF ablation is expanded to elderly populations, our study found that AF ablation success rates were similar in both elderly and younger patients. However, older patients experience higher rates of complications that should be considered when offering the procedure and as a means to improve outcomes with future innovations. This article is protected by copyright. All rights reserved.

Cardiac resynchronization therapy using a pacemaker or a defibrillator: Patient selection and evidence to support it

Cardiac resynchronization therapy (CRT) is an established treatment for patients with heart failure (HF), myocardial dysfunction and prolonged ventricular depolarization on surface electrocardiogram. CRT can be delivered by a pacemaker (CRT-P) or a combined pacemaker-defibrillator (CRT-D). Although these two types of devices are very different in size, function, and cost, current published guidelines do not distinguish between them, leaving the choice of which device to implant to the treating physician and the informed patient. In this paper, we review the published CRT clinical trial literature with focus on the outcomes of HF patients treated with CRT-P versus CRT-D. We also attempt to provide guidance as to the appropriate choice of CRT device type, in the absence of randomized prospective trials geared to answer this specific question.

Melatonin to Rescue the Aged Heart: Antiarrhythmic and Antioxidant Benefits

Aging comes with gradual loss of functions that increase the vulnerability to disease, senescence, and death. The mechanisms underlying these processes are linked to a prolonged imbalance between damage and repair. Damaging mechanisms include oxidative stress, mitochondrial dysfunction, chronodisruption, inflammation, and telomere attrition, as well as genetic and epigenetic alterations. Several endogenous tissue repairing mechanisms also decrease. These alterations associated with aging affect the entire organism. The most devastating manifestations involve the cardiovascular system and may lead to lethal cardiac arrhythmias. Together with structural remodeling, electrophysiological and intercellular communication alterations during aging predispose to arrhythmic events. Despite the knowledge on repairing mechanisms in the cardiovascular system, effective antiaging strategies able to reduce the risk of arrhythmias are still missing. Melatonin is a promising therapeutic candidate due to its pleiotropic actions. This indoleamine regulates chronobiology and endocrine physiology. Of relevance, melatonin is an antiaging, antioxidant, antiapoptotic, antiarrhythmic, immunomodulatory, and antiproliferative molecule. This review focuses on the protective effects of melatonin on age-induced cardiac functional and structural alterations, potentially becoming a new fountain of youth for the heart.

VT ablation in geriatric patients with structural heart disease: Should there still be an age limit?

INTRODUCTION

This study sought to examine the feasibility and outcome of ablation of ventricular tachycardias (VTs) in a contemporary cohort of geriatric patients with structural heart disease (SHD).

BACKGROUND

Geriatric patients are often underrepresented in large studies. As frailty is becoming an increasing problem, we need to examine the best course of action for this population.

METHODS AND RESULTS

We investigated 68 SHD-patients ≥ 75 years old undergoing VT-ablation (men 88%, ischemic cardiomyopathy 77%, electrical storm 72%, mean left ventricular ejection fraction 31%) and divided the cohort into two groups: 75-79 years old (n = 51) and ≥80 years old (n = 17). The two groups showed similar results regarding noninducibility as ablation endpoint (p = .693), major procedure-related complications (p = .488), and VT-recurrence (p = .882) during the 39-month follow-up. At the end of the follow-up, 10 patients in the octogenarian group (59%) versus 16 patients of the other group (31%) died.

CONCLUSION

Geriatric patients with SHD including octogenarians showed similar results regarding procedural endpoints, freedom of VT, and major procedure-associated complications after VT-ablation. When ablation is indicated, age alone should not be an inhibiting factor to treat these patients.

Ablation of paroxysmal and persistent atrial fibrillation in the very elderly real-world data on safety and efficacy

Background

The role and technique of catheter ablation of atrial fibrillation (AF) in the elderly is unclear. While in young patients pulmonary vein isolation (PVI) has evolved as first option, in older patients decision is often made in favor of drugs as higher complication rates and less benefit are suspected. Therefore, data on PVI of paroxysmal and persistent AF in these patients is still sparse but of eminent importance.

Hypothesis

PVI is comparably safe in the very elderly with similar recurrence and complication rates.

Methods

We enrolled all patients (n = 146) aged >75 years who underwent a first PVI over a period of 10 years (2009‐2019) from our prospective single‐center ablation registry. Mean follow‐up time was 231 ± 399 days.

Results

Acute ablation success defined as complete PVI and sinus rhythm at the end of the ablation procedure was high (99%). Severe periprocedural complications occurred in 3.3% (stroke/TIA n = 2; 1.3%; pericardial effusion n = 3; 2%). In 4.6% of patients symptomatic sick‐sinus‐syndrome was unmasked after PVI resulting in pacemaker implantation. There were no deaths related to PVI. Recurrence rate of symptomatic AF was 37.3% resulting in a Re‐PVI and/or substrate ablation in 32 pts (20.9%). During follow‐up pacemaker implantation plus atrioventricular node ablation was performed in 10 pts (6.8%). There was a trend toward lower recurrence rates with single‐shot devices (cryoballoon, multielectrode phased‐radiofrequency ablation catheter) than with point‐by‐point radiofrequency while complication rates did not differ.

Conclusion

PVI for AF is a feasible treatment option also in patients >75 years with a reasonable success and safety profile. Higher success rates occurred in patients treated with a single‐shot device as compared to point‐by‐point ablation.

Clinical efficacy and safety of radiofrequency catheter ablation for atrial fibrillation in patients aged ≥80 years

AIM

To evaluate the clinical safety and efficacy of radiofrequency catheter ablation for atrial fibrillation (AF) in patients aged ≥80 years.

METHODS

A total of 333 AF patients aged ≥60 years were enrolled, who underwent contact force-guided radiofrequency catheter ablation with uninterrupted anticoagulation. All patients were followed-up for at least 12 months. Success was defined by the absence of episodes of AF/atrial tachycardia lasting more than 30 seconds after a 3-month blanking period, without antiarrhythmic drugs.

RESULTS

Compared to patients aged 60-79 years (Group 2, n = 244), patients aged ≥80 years (Group 1, n = 89) were presented with higher rate of diabetes (36.0% vs 22.1%, P = .011), lower body mass index (23.4 ± 3.1 vs 24.9 ± 3.4 kg/m² , P = .001), lower creatinine clearance (56.9 ± 16.5 vs 83.3 ± 24.5 mL/min, P < .001), higher CHA₂ DS₂ -VASc score (4.3 ± 1.3 vs 3.3 ± 1.4, P < .001), and HAS-BLED score (2.2 ± 0.8 vs 1.8 ± 0.8, P < .001). Wide antral pulmonary vein isolation was achieved in all patients, and there was no significant difference in procedure time, ablation time, fluoroscopy time, and complications rate between two age groups (P > .05). After a mean follow-up of 24.4 ± 9.6 months, the overall success rate was 78.2% in Group 1 and 78.9% in Group 2 (P = .622).

CONCLUSIONS

Radiofrequency ablation with contact force sensing catheters for AF is safe and effective in selected patients aged ≥80 years.

Predictors of clinical outcomes after cardiac resynchronization therapy in patients ≥75 years of age: a retrospective cohort study

Background

Cardiac resynchronization therapy has been shown to benefit selected patients with heart failure and reduced ejection fraction. Older patients have been underrepresented in randomized trials. This study was conducted to determine whether predictive factors for cardiac resynchronization therapy outcomes differ in patients older and younger than 75 years of age.

Methods

Consecutive patients who received a cardiac resynchronization device cardiac resynchronization therapy between 2013 and 2016 in our center were retrospectively included in this cohort study. The primary endpoint was cardiac resynchronization therapy effectiveness, which was defined as survival for one year with both no heart failure hospitalization and improvement by one or more NYHA class. The secondary endpoints were mortality, complications, and device therapies.

Results

Among the 243 patients included, 102 were ≥ 75 years old. Cardiac resynchronization therapy effectiveness was observed in 70 patients (50%) < 75 years old and in 48 patients (47%) ≥75 years old (p = 0.69). NYHA class ≥III (OR = 6.02; CI95% [1.33–18.77], p = 0.002) was a predictive factor for cardiac resynchronization therapy effectiveness only in the ≥75-year-old group, while atrial fibrillation was independently negatively associated with the primary endpoint in the < 75-year-old group (OR = 0.28; CI95% [0.13–0.62], p = 0.001). The one-year mortality rate was 14%, with no difference between age groups. Rescue cardiac resynchronization therapy and atrial fibrillation were independent predictive factors for mortality in both age groups. Eighty-two complications occurred in 45 patients (19%), with no difference between groups. Defibrillator use and QRS duration were independent predictive factors for complications in both age groups. There was no difference between groups considering device therapies.

Conclusion

At one year, cardiac resynchronization therapy response is not compromised by patient age. In older patients, highly symptomatic individuals with NYHA class ≥III have better outcomes after cardiac resynchronization therapy.

Anxiety, age, education and activities of daily living as predictive factors of the occurrence of frailty syndrome in patients with heart rhythm disorders

OBJECTIVES

Frailty is one of the geriatric syndromes that are caused by subclinical impairment of many organs, leading to the loss of reserves and the ability to maintain homeostasis. Aim of the study was to assess which factors including anxiety and depression can be predictive factors for the occurrence of frailty syndrome in patients with heart rhythm disorders.

METHODS

The study included 171 consecutive patients >64 years (73.91 ± 6.72; 48.5% W) with diagnosed cardiac arrhythmias who had been qualified for pacemaker implantation. The Tilburg Frailty Indicator scale as well as the Hospital Anxiety and Depresion Scale (HADS) were used.

RESULTS

The average HADS results in the frailty group was significantly higher 7.42 ± 2.63 compared to the robust patients 6.33 ± 2.83; p =0.0019. Similar results were observed in patients with atrio-ventricular blocks (AVB): HADS-A: frail 8.23 ± 2.13 vs. robust 6.62 ± 2.27; p = 0.0036 and HADS-D: frail 8.84 ± 2.85 vs. robust 7.17 ± 2.48; p =0.0086. The multiple regression model showed that age (p =0.0023), education (p =0.0001), ADL (p =0.0001) and the severity of the anxiety (p = 0.0414) were important predictors of the dependent variable and predicted higher levels of frailty syndrome.

CONCLUSION

Anxiety, age, education and the activities of daily living can be predictive factors of the occurrence of frailty syndrome in patients with heart rhythm disorders who have been qualified for pacemaker implantation.

Team Management of the Ventricular Tachycardia Patient

Ventricular tachycardia is a common arrhythmia in patients with structural heart disease and heart failure, and is now seen more frequently as these patients survive longer with modern therapies. In addition, these patients often have multiple comorbidities. While anti-arrhythmic drug therapy, implantable cardioverter-defibrillator implantation and ventricular tachycardia ablation are the mainstay of therapy, well managed by the cardiac electrophysiologist, there are many other facets in the care of these patients, such as heart failure management, treatment of comorbidities and anaesthetic interventions, where the expertise of other specialists is essential for optimal patient care. A coordinated team approach is therefore essential to achieve the best possible outcomes for these complex patients.

Ventricular Tachycardia Ablation in the Elderly: An International Ventricular Tachycardia Center Collaborative Group Analysis

BACKGROUND

Successful ventricular tachycardia (VT) ablation is associated with improved survival in patients with heart failure. However, the safety and efficacy of VT ablation in the elderly, a population with higher competing nonsudden death risk and comorbidities, have not been well defined.

METHODS AND RESULTS

The International Ventricular Tachycardia Center Collaborative Study Group registry of 2061 patients who underwent VT ablation at 12 international centers was analyzed. Kaplan-Meier analysis was used to estimate survival of patients ≥70 years with and without VT recurrence. Of the 2049 patients who met inclusion criteria, 681 (33%) patients were ≥70 years of age (mean age, 75±4 years). Among these, 92% were men, 71% had ischemic VT, and 42% had VT storm at presentation. Mean (±SD) left ventricular ejection fraction was 30±11%. Compared with patients <70 years, patients ≥70 years had higher in-hospital (4.4% versus 2.3%; P=0.01) and 1-year mortality (15% versus 11%; P=0.002) but a similar incidence of VT recurrence at 1 year (26% versus 25%; P=0.74) and time to VT recurrence (280 versus 289 days; P=0.20). Absence of VT recurrence during follow-up was strongly associated with improved survival in patients ≥70 years.

CONCLUSION

VT ablation in the elderly is feasible and reasonably safe with a modestly higher in-hospital and 1-year mortality, with similar rates of VT recurrence at 1 year compared with younger patients. Successful VT ablation, that is, lack of VT recurrence, is strongly associated with improved survival even in this elderly subgroup.

DIAGNOSIS OF MULTICLASS TACHYCARDIA BEATS USING RECURRENCE QUANTIFICATION ANALYSIS AND ENSEMBLE CLASSIFIERS

Atrial Fibrillation (A-Fib), Atrial Flutter (AFL) and Ventricular Fibrillation (V-Fib) are fatal cardiac abnormalities commonly affecting people in advanced age and have indication of life-threatening condition. To detect these abnormal rhythms, Electrocardiogram (ECG) signal is most commonly visualized as a significant clinical tool. Concealed non-linearities in the ECG signal can be clearly unraveled using Recurrence Quantification Analysis (RQA) technique. In this paper, RQA features are applied for classifying four classes of ECG beats namely Normal Sinus Rhythm (NSR), A-Fib, AFL and V-Fib using ensemble classifiers. The clinically significant ([Formula: see text]) features are ranked and fed independently to three classifiers viz. Decision Tree (DT), Random Forest (RAF) and Rotation Forest (ROF) ensemble methods to select the best classifier. The training and testing of the feature set is accomplished using 10-fold cross-validation strategy. The RQA coefficients using ROF provided an overall accuracy of 98.37% against 96.29% and 94.14% for the RAF and DT, respectively. The results achieved evidently ratify the superiority of ROF ensemble classifier in the diagnosis of A-Fib, AFL and V-Fib. Precision of four classes is measured using class-specific accuracy (%) and reliability of the performance is assessed using Cohen’s kappa statistic ([Formula: see text]). The developed approach can be used in therapeutic devices and help the physicians in automatic monitoring of fatal tachycardia rhythms.

EHRA research network surveys: 6 years of EP wires activity

Clinical practice should follow guidelines and recommendations mainly based on the results of controlled trials, which are often conducted in selected populations and special conditions, whereas clinical practice may be influenced by factors different from controlled scientific studies. Hence, the real-world setting is better assessed by the observational registries enrolling patients for longer periods of time. However, this may be difficult, expensive, and time-consuming. In 2009, the Scientific Initiatives Committee of the European Heart Rhythm Association (EHRA) has instigated a series of surveys covering the controversial issues in clinical electrophysiology (EP). With this in mind, an EHRA EP research network has been created, which included EP centres in Europe among which the surveys on 'hot topic' were circulated. This review summarizes the overall experience conducting EP wires over the past 6 years, categorizing and assessing the topics regarding clinical EP, and evaluating the acceptance and feedback from the responding centres, in order to improve participation in the surveys and better address the research needs and aspirations of the European EP community.

Primary prevention implantable cardioverter-defibrillator and cardiac resynchronization therapy-defibrillator in elderly patients: results of a Spanish multicentre study

AIMS

Currently, there continues to be a lack of evidence regarding outcomes associated with device-based therapy for ventricular arrhythmias in elderly patients, even more in primary-prevention indications. We aimed to describe the follow-up in terms of efficacy and safety of implantable cardioverter-defibrillator (ICD) therapy in a large cohort of elderly patients.

METHODS AND RESULTS

Retrospective multicentre study performed in 15 Spanish hospitals. Consecutive patients referred for ICD implantation before 2011 were included. One hundred and sixty-two of 1174 patients (13.8%) ≥75 years were considered as 'elderly'. When compared with those patients <75, this subgroup presented more co-morbid conditions, including hypertension, chronic obstructive pulmonary disease , and renal failure, and more previous hospitalizations due to heart failure (HF). During a mean follow-up of 104.4 ± 3.3 months, 162 patients (14%) died, 120 in the younger age (12.4%), and 42 (24.4%) in the elderly. Kaplan-Meier analysis showed an increased probability of death with increasing age (17, 24, 28, and 69% at 12, 24, 48, and 60 months of follow-up in the elderly group). There was neither difference regarding the rate of appropriate nor inappropriate ICD intervention.

CONCLUSION

In a real-world scenario, elderly patients comprise ∼15% of ICD implantations for primary prevention of sudden cardiac death (SCD). Although the rate of appropriate therapy is similar between groups, the benefit of ICD is attenuated for a major increase in mortality risk among those patients ≥75 years at the moment of device implantation.