Long-term outcome of the atrioventricular node ablation and pacemaker implantation for symptomatic refractory atrial fibrillation

Atherosclerotic Cardiovascular Disease: Risk Assessment, Prevention and Treatment Strategies

Despite enormous advances in both surgical and pharmacological treatment, cardiovascular diseases are still the most common cause of morbidity and disability in the western world [...].

Biventricular versus Conduction System Pacing after Atrioventricular Node Ablation in Heart Failure Patients with Atrial Fibrillation

Conduction system pacing (CSP) modalities, including His-bundle pacing (HBP) and left bundle branch pacing (LBBP), are increasingly used as alternatives to biventricular (BiV) pacing in heart failure (HF) patients scheduled for pace and ablate strategy. The aim of the study was to compare clinical outcomes of HF patients with refractory AF who received either BiV pacing or CSP in conjunction with atrio-ventricular node ablation (AVNA). Fifty consecutive patients (male 48%, age 70 years (IQR 9), left ventricular ejection fraction (LVEF) 39% (IQR 12)) were retrospectively analysed. Thirteen patients (26%) received BiV pacing, 27 patients (54%) HBP and 10 patients (20%) LBBP. All groups had similar baseline characteristics and acute success rate. While New York Heart. Association (NYHA) class improved in both HBP (p < 0.001) and LBBP (p = 0.008), it did not improve in BiV group (p = 0.096). At follow-up, LVEF increased in HBP (form 39% (IQR 15) to 49% (IQR 16), p < 0.001) and LBBP (from 28% (IQR 13) to 40% (IQR 13), p = 0.041), but did not change in BiV group (p = 0.916). Conduction system pacing modalities showed superior symptomatic and echocardiographic improvement compared to BiV pacing after AVNA. With more stable pacing parameters, LBBP could present a more feasible pacing option compared to HBP.

Biventricular versus His bundle pacing after atrioventricular node ablation in heart failure patients with narrow QRS

Background: His bundle pacing (HBP) is a physiological alternative to biventricular (BiV) pacing. We compared short-term results of both pacing approaches in symptomatic atrial fibrillation (AF) patients with moderately reduced left ventricular (LV) ejection fraction (EF ≥35% and <50%) and narrow QRS (≤120 ms) who underwent atrioventricular node ablation (AVNA).Methods: Thirty consecutive AF patients who received BiV pacing or HBP in conjunction with AVNA between May 2015 and January 2020 were retrospectively assessed. Electrocardiographic, echocardiographic, and clinical data at baseline and 6 months after the procedure were assessed.Results: Twenty-four patients (age 68.8 ± 6.5 years, 50% female, EF 39.6 ± 4%, QRS 95 ± 10 ms) met the inclusion criteria, 12 received BiV pacing and 12 HBP. Both groups had similar acute procedure-related success and complication rates. HBP was superior to BiV pacing in terms of post-implant QRS duration, implantation fluoroscopy times, reduction of indexed LV volumes (EDVi 63.8 (49.6-81) mL/m² vs. 79.9 (66-100) mL/m², p = 0.055; ESVi 32.7 (25.6-42.6) mL/m² vs. 46.4 (42.9-68.1) mL/m², p = 0.009) and increase in LVEF (46 (41-55) % vs. 38 (35-42) %, p = 0.005). However, the improvement of the NYHA class was similar in both groups.Conclusions: In symptomatic AF patients with moderately reduced EF and narrow QRS undergoing AVNA, HBP could be a conceivable alternative to BiV pacing. Further prospective studies are warranted to address the outcomes between both 'ablate and pace' strategies.

Long-term outcomes after radiofrequency catheter ablation of the atrioventricular node: The experience of a Portuguese tertiary center

INTRODUCTION

In patients with supraventricular arrhythmias and high ventricular rate, unresponsive to rate and rhythm control therapy or catheter ablation, atrioventricular (AV) node ablation may be performed.

OBJECTIVES

To assess long-term outcomes after AV node ablation and to analyze predictors of adverse events.

METHODS

We performed a detailed retrospective analysis of all patients who underwent AV node ablation between February 1997 and February 2019, in a single Portuguese tertiary center.

RESULTS

A total of 123 patients, mean age 69±9 years and 52% male, underwent AV node ablation. Most of them presented atrial fibrillation at baseline (65%). During a median follow-up of 8.5 years (interquartile range 3.8-11.8), patients improved heart failure (HF) functional class (NYHA class III-IV 46% versus 13%, p=0.001), and there were reductions in hospitalizations due to HF (0.98±1.3 versus 0.28±0.8, p=0.001) and emergency department (ED) visits (1.1±1 versus 0.17±0.7, p=0.0001). There were no device-related complications. Despite permanent pacemaker stimulation, left ventricular ejection fraction did not worsen (47±13% vs. 47%±12, p=0.63). Twenty-eight patients died (23%). The number of ED visits due to HF before AV node ablation was an independent predictor of the composite adverse outcome (OR 1.8, 95% CI 1.24-2.61, p=0.002).

CONCLUSIONS

Despite pacemaker dependency, the clinical benefit of AV node ablation persisted at long-term follow-up. The number of ED visits due to HF before AV node ablation was an independent predictor of the composite adverse outcome. AV node ablation should probably be considered earlier in the treatment of patients with supraventricular arrhythmias and HF, especially in cases that are unsuitable for selective ablation of the specific arrhythmia.

A Novel and Practical Method of Performing Atrioventricular Nodal Ablation via a Superior Approach in Patients with Refractory Atrial Fibrillation Undergoing Cardiac Resynchronization Device Implantation

Atrioventricular node (AVN) ablation is a strategy to manage patients with drug-refractory atrial fibrillation (AF) and heart failure in whom cardiac resynchronization therapy (CRT) device implantation has been prescribed. This study describes a practical method to perform these two procedures using the same surgical site. Twenty-seven patients were indicated for AVN ablation and concurrent CRT device implantation while presenting with AF and rapid ventricular response (RVR) refractory to medical therapy. After placement of the right and left ventricular leads, a third puncture was made in the axillary vein to obtain access to perform the ablation. After hand-injecting contrast media through a RAMP™ (Abbott Laboratories, Chicago, IL, USA) sheath positioned in the right atrial cavity, the anatomical area corresponding to the AVN was identified using fluoroscopy cine runs obtained in the right anterior oblique and left anterior oblique projections. The adequate site for ablation was confirmed by the bipolar recording of a His-bundle deflection at the tip of the ablation catheter. Radiofrequency energy was delivered to achieve complete heart block. Subsequently, device implant was completed. The method was successfully applied in 27 consecutive cases, achieving permanent complete heart block in all patients. The mean radiofrequency time to achieve heart block was 110 seconds ± 43 seconds. The average procedural time including AVN ablation and device implant was 87 minutes ± 21 minutes. The images obtained with the hand-injected contrast media provided adequate information to readily identify the anatomical area corresponding to the AVN with 100% accuracy. This study suggests that ablation of the AVN can be safely and effectively accomplished via a superior approach in patients undergoing a CRT device implant.

Long-term experience of atrioventricular node ablation in patients with refractory atrial arrhythmias

Atrial fibrillation and other atrial tachyarrhythmias are increasing with age and concomitant morbidity. First options in symptomatic patients are drug treatment and catheter ablation. Nevertheless, a considerable number of patients suffer from refractory atrial tachyarrhythmias despite treatment. Atrioventricular node ablation (AVNA) may be helpful in many of these patients. Therefore, we investigated AVNA patients with a long-term follow-up. We enrolled 82 patients with a follow-up longer than 1 year receiving AVNA for drug- and ablation-resistant atrial tachyarrhythmias (AA) in a retrospective manner. Mean follow-up duration was 48 ± 24 months. 50% of the patients initially received AVNA to optimize biventricular pacing in cardiac resynchronization therapy, the other 50% because of refractory symptomatic tachyarrhythmias. Persistent AV block was achieved in every patient. Symptom relief and patient satisfaction were high during follow-up. Due to system upgrades there were 63% of patients with a biventricular system during follow-up. In these patients, left-ventricular ejection fraction (LV-EF) increased by 7% (42-49%) after ablation. AVNA is effective in increasing biventricular pacing as well as for symptom relief in patients with refractory atrial tachyarrhythmias. AVNA should be considered as a valuable option in patients with refractory atrial tachyarrhythmias lacking other treatment options.

Clinical predictors of challenging atrioventricular node ablation procedure for rate control in patients with atrial fibrillation

INTRODUCTION

Atrioventricular node (AVN) ablation is usually a simple procedure but may sometimes be challenging. We aimed at identifying pre-procedural clinical predictors of challenging AVN ablation.

METHODS

Patients referred for AVN ablation from 2009 to 2015 were retrospectively included. Baseline clinical data, procedural variables and outcomes of AVN ablation were collected. A "challenging procedure" was defined 1) total radiofrequency delivery to get persistent AVN block≥400s, 2) need for left-sided arterial approach or 3) failure to obtain AVN ablation.

RESULTS

200 patients were included (71±10years). A total of 37 (18.5%) patients had "challenging" procedures (including 9 failures, 4.5%), while 163 (81.5%) had "non-challenging" ablations. In multivariable analysis, male sex (Odds ratio (OR)=4.66, 95% confidence interval (CI): 1.74-12.46), body mass index (BMI, OR=1.08 per 1kg/m², 95%CI 1.01-1.16), operator experience (OR=0.40, 95%CI 0.17-0.94), and moderate-to-severe tricuspid regurgitation (TR, OR=3.65, 95%CI 1.63-8.15) were significant predictors of "challenging" ablations. The proportion as a function of number of predictors was analyzed (from 0 to 4, including male sex, operator inexperience, a BMI>23.5kg/m² and moderate-to-severe TR). There was a gradual increase in the risk of "challenging" procedure with the number of predictors by patient (No predictor: 0%; 1 predictor: 6.3%; 2 predictors: 16.5%; 3 predictors: 32.5%; 4 predictors: 77.8%).

CONCLUSIONS

Operator experience, male sex, higher BMI and the degree of TR were independent predictors of "challenging" AVN ablation procedure. The risk increases with the number of predictors by patient.

The current approach of atrial fibrillation management

Atrial fibrillation (AF) is the most commonly encountered arrhythmia in clinical practice. Aging populations coupled with improved outcomes for many chronic medical conditions has led to increases in AF diagnoses. AF is also known to be associated with an increased risk of adverse events such as transient ischemic attack, ischemic stroke, systemic embolism, and death. This association is enhanced in select populations with preexisting comorbid conditions such as chronic heart failure. The aim of this review is to highlight the advances in the field of cardiology in the management of AF in both acute and long-term settings. We will also review the evolution of anticoagulation management over the past few years and landmark trials in the development of novel oral anticoagulants (NOACs), reversal agents for new NOACs, nonpharmacological options to anticoagulation therapy, and the role of implantable loop recorder in AF management.

Atrial fibrillation in the elderly: a review

Atrial fibrillation (AF) is common in the elderly population. Elderly patients with AF are often asymptomatic, may have atypical presentation or may present with heart failure or thromboembolic complications. The optimal management strategy of AF in the elderly population is challenging. We present an overview of AF in elderly patients, in particular addressing the pros and cons of various management strategies, and provide a practical approach within the guidelines.

Device therapy for acute systolic heart failure and atrial fibrillation

Patients with newly diagnosed cardiomyopathy require careful assessment of cause and initiation of treatment before the decision is made to implant an internal cardiac defibrillator. In patients with medicine-refractory atrial fibrillation and cardiomyopathy, atrioventricular node ablation and implantation of a biventricular pacemaker is the therapy of choice when tachycardia-induced cardiomyopathy is suspected and curative therapy is not possible.

Effect Of Catheter Ablation On Quality Of Life In Atrial Fibrillation

Atrial fibrillation (AF) is the most common sustained arrhythmia seen in clinical practice, affecting approximately 1% of the overall population. While rarely life-threatening, AF is almost universally associated with increased morbidity and mortality, predominantly through an increased risk of thromboembolic events, left ventricular dysfunction, as well as significant impairments in functional capacity and health-related quality of life (HRQOL).[1-8] Improvement in HRQOL, with a secondary reduction of disability and health-care resource utilization, is one of the major therapeutic goals in the management of AF.

Ventricular rate control of atrial fibrillation in heart failure

In the last few years, there has been a major shift in the treatment of atrial fibrillation (AF) in the setting of hear failure (HF), from rhythm to ventricular rate control in most patients with both conditions. In this article, the authors focus on ventricular rate control and discuss the indications; the optimal ventricular rate-control target, including detailed results of the Rate Control Efficacy in Permanent Atrial Fibrillation: a Comparison Between Lenient versus Strict Rate Control II (RACE II) study; and the pharmacologic and nonpharmacologic options to control the ventricular rate during AF in the setting of HF.

Effect of pacing method on risk of sudden death after atrioventricular node ablation and pacemaker implantation in patients with atrial fibrillation

BACKGROUND

Sudden death may occur after radiofrequency catheter ablation of the atrioventricular node (AVN) and permanent pacemaker implantation. It is unclear whether a faster initial heart rate with gradual rate reduction decreases the risk of sudden death.

OBJECTIVE

To evaluate the effects of initial pacing at a faster rate after AVN ablation, with a gradual rate decrease over 3 months, on the rate of sudden death in patients with atrial fibrillation.

METHODS

We compared the rate of likely or possible procedure-related sudden death in 2 groups of patients who had AVN ablation and pacemaker implantation. The study cohort was treated between January 2005 and December 2009, and pacemakers were programmed to a lower rate of 90 beats/min after the procedure, with a monthly decrement of 10 beats/min until 60 beats/min was reached. The control group was treated between July 1990 and December 1998 when pacemakers were programmed to a lower rate of 60 beats/min immediately after ablation.

RESULTS

The study cohort included 520 patients (mean age 73.6 ± 10.3 years), and the control cohort comprised 334 patients (mean age 68.1 ± 1.1 years). Sudden death deemed likely or possibly related to ablation and pacemaker implantation occurred in 1 patient in the study cohort (0.2%) and in 7 patients (2.1%) in the control group (P = .007).

CONCLUSIONS

Sudden death was significantly decreased in the study cohort compared to controls. The faster lower pacing rate immediately after AVN ablation with a gradual decrease is a plausible mechanism for the improved clinical outcome.

Cardiac resynchronization therapy after atrioventricular junction ablation for symptomatic atrial fibrillation: a meta-analysis

AIMS

Atrioventricular junction (AVJ) ablation with permanent pacing improves symptoms in selected patients with atrial fibrillation (AF). The optimal pacing modality after AVJ ablation remains unclear. We performed a meta-analysis of randomized controlled trials to examine whether cardiac resynchronization therapy (CRT) is superior to right ventricular (RV) pacing in this patient population.

METHODS AND RESULTS

We searched the MEDLINE and EMBASE databases for studies evaluating the effect of CRT vs. RV pacing after AVJ ablation for AF. Pooled risk ratios (RRs) and mean differences with 95% confidence intervals (CIs) were calculated for categorical and continuous outcomes, respectively, using a random effects model. Five trials involving 686 patients (413 in CRT and 273 in RV pacing group) were included in the analysis. On the basis of the pooled estimate across the studies, CRT resulted in a non-significant reduction in mortality (RR = 0.75, 95% CI 0.43-1.30; P= 0.30) and a significant reduction in hospitalizations for heart failure (RR = 0.38, 95% CI = 0.17-0.85; P= 0.02) compared with RV pacing. Cardiac resynchronization therapy did not improve 6 min walk distance (mean difference 15.7, 95% CI -7.2 to 38.5 m; P= 0.18) and Minnesota Living with Heart Failure quality-of-life score (mean difference -3.0, 95% CI -8.6 to 2.6; P= 0.30) compared with RV pacing. The change in left ventricular ejection fraction between baseline and 6 months favoured CRT (mean change 2.0%, 95% CI 1.5-2.4%; P< 0.001).

CONCLUSION

Cardiac resynchronization therapy may be superior to RV pacing in patients undergoing AVJ ablation for AF. Further studies, adequately powered to detect clinical outcomes, are required.

A Patient with a 40% Ejection Fraction Undergoes Atrioventricular Nodal Ablation for the Management of Atrial Fibrillation with Rapid Ventricular Rates. What Type of Device Should He Receive?

Patients with symptomatic atrial fibrillation not amenable to pharmacologic therapy or catheter ablation may be appropriate candidates for atrioventricular nodal (AVN) ablation and placement of a permanent pacemaker. The question arises as to whether to implant a right ventricular (RV)-only pacing device or a cardiac resynchronization therapy (CRT) device. This article examines 2 similar cases of patients presenting for AVN ablation who received RV-only pacing devices but had different clinical outcomes. This article discusses existing guidelines and studies that can help clinicians address the challenging question of whether an initial implant of a CRT pacing device is warranted in such patients.

Adverse effects of permanent atrial fibrillation on heart failure in patients with preserved left ventricular function and chronic right apical pacing for complete heart block

BACKGROUND

The impact of atrial fibrillation (AF) on heart failure (HF) was evaluated in patients with preserved left ventricular (LV) function and long-term right ventricular (RV) pacing for complete heart block.

METHODS

Clinical, echocardiographic, and laboratory parameters of HF were assessed in 35 patients with established AF who had undergone ablation of the atrioventricular node and pacemaker implantation (Group A) and 31 patients who received dual-chamber pacing for spontaneous complete heart block (Group B).

RESULTS

During a follow-up period of 12.7 ± 7.5 years, New York Heart Association (NYHA) functional class increased from 1.3 ± 0.5 to 2.1 ± 0.6 (p < 0.0001) in Group A, and from 1.3 ± 0.4 to 1.6 ± 0.7 (p < 0.01) in Group B. Left ventricular ejection fraction (LVEF) decreased from 59.7 ± 5.1 to 53.0 ± 8.2 (p < 0.0001) in Group A, but remained stable (58.6 ± 4.2 vs. 56.9 ± 7.0 %, p = 0,21) in Group B. At the end of follow-up, markers of LV function were moderately depressed in Group A compared with those in Group B: NYHA class 2.1 ± 0.6 versus 1.6 ± 0.7, p = 0.001; LVEF 53.0 ± 8.2 versus 56.9 ± 7.0 %, p < 0.05; LV diastolic diameter 53.6 ± 5.8 mm versus 50.7 ± 4.9 mm, p < 0.05; N-terminal pro-brain natriuretic peptide (NT-proBNP) 1116.8 ± 883.9 versus 622.9 ± 1059.4 pg/ml, p < 0.05. Progression of paroxysmal AF to permanent AF during follow-up was common, while new onset of AF was rare. Permanent AF was an independent predictor of declining LVEF >10 %, increasing NYHA class ≥1, and NT-proBNP levels >1,000 pg/ml.

CONCLUSIONS

Permanent AF was associated with adverse effects on LV function and symptoms of HF in patients with long-term RV pacing for complete heart block, and appears to play an important role in the development of HF in this specific patient cohort.

Atrioventricular junction ablation and pacemaker implantation for heart failure associated with atrial fibrillation: potential issues and therapies in the setting of acute heart failure syndrome

Atrial fibrillation is the most common arrhythmia and is especially clinically important in patients with heart failure. Prolonged atrial fibrillation with high ventricular rate response may lead to development or worsening of left ventricular function. If adequate heart rate control cannot be obtained medically, often patients will undergo pacemaker implant and catheter ablation of the atrioventricular junction. This intervention can have profound effects on the course of heart failure. This article reviews the technique, complications, outcome data, and alternatives to this management strategy. The potential role of this therapeutic modality in those hospitalized with acute heart failure syndromes is discussed.

Cardiac resynchronization therapy in patients undergoing atrioventricular junction ablation for permanent atrial fibrillation: a randomized trial

AIMS

On the basis of the current knowledge, cardiac resynchronization therapy (CRT) cannot be recommended as a first-line treatment for patients with severely symptomatic permanent atrial fibrillation undergoing atrioventricular (AV) junction ablation. We examined whether CRT was superior to conventional right ventricular (RV) pacing in reducing heart failure (HF) events.

METHODS AND RESULTS

In this prospective, multi-centre study, we randomly assigned 186 patients, in whom AV junction ablation and CRT device implantation had been successfully performed, to receive optimized echo-guided CRT (97 patients) or RV apical pacing (89 patients). The data were analysed according to the intention-to-treat principle. During a median follow-up of 20 months (interquartile range 11-24), the primary composite endpoint of death from HF, hospitalization due to HF, or worsening HF occurred in 11 (11%) patients in the CRT group and 23 (26%) patients in the RV group [CRT vs. RV group: sub-hazard ratio (SHR) 0.37 ( 95% CI 0.18-0.73), P = 0.005]. In the CRT group, compared with the RV group, fewer patients had worsening HF [SHR 0.27 (95% CI 0.12-0.58), P = 0.001] and hospitalizations for HF [SHR 0.20 (95% CI 0.06-0.72), P = 0.013]. Total mortality was similar in both groups [hazard ratio (HR) 1.57 (95% CI 0.58-4.27), P = 0.372]. The beneficial effects of CRT were consistent in patients who had ejection fraction ≤35%, New York Heart Association Class ≥III and QRS width ≥120 and in those who did not. At multi-variable Cox regression, only CRT mode remained an independent predictor of absence of clinical failure during the follow-up [HR = 0.23 (95% CI 0.08-0.66), P = 0.007].

CONCLUSIONS

In patients undergoing 'Ablate and Pace' therapy for severely symptomatic permanent atrial fibrillation, CRT is superior to RV apical pacing in reducing the clinical manifestations of HF. (ClinicalTrials.gov number: NCT00111527).

Atrioventricular nodal ablation versus antiarrhythmic drugs after permanent pacemaker implantation for bradycardia-tachycardia syndrome

Patients often require antiarrhythmic drugs to control tachycardia after permanent pacemaker implantation (PMI) for bradycardia-tachycardia syndrome. We compared atrioventricular nodal ablation (AVNA) to antiarrhythmic drugs after PMI for bradycardia-tachycardia syndrome. Twenty-eight symptomatic patients with bradycardia-tachycardia syndrome, all of which had a long pause after termination of paroxysmal atrial fibrillation, underwent PMI with RV lead placement at the mid-septum site. Among these patients, 14 underwent PMI and AVNA (AVNA group). The remaining 14 patients underwent PMI only, and continued to take anti-arrhythmic drugs (drug group). We compared cardiac function (cardio-thoracic ratio on chest X-ray, left atrial diameter, left ventricular end-diastolic dimension, and left ventricular-ejection fraction by echocardiography), exercise tolerance (6-min walking distance), symptoms, and the number of antiarrhythmic drugs just before and 6 months after PMI. Baseline characteristics were similar between the two groups, except for the number of antiarrhythmic drugs. Six months after PMI, cardiac function, exercise tolerance, and symptoms did not differ significantly between the two groups. Compared to the drug group (p < 0.01), the number of antiarrhythmic drugs was significantly smaller in the AVNA group 6 months after PMI. Patients who underwent AVNA concurrently with PMI with RV lead placement at the mid-septum site for bradycardia-tachycardia syndrome were able to reduce the intake of drugs and improve their tachycardia-related symptoms while maintaining cardiac function and exercise tolerance.

Atrial fibrillation-the final frontier

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and represents a significant health care issue. The diagnosis and management of AF uses a significant proportion of the health care budget and is responsible for substantial morbidity and mortality. Restoration and maintenance of sinus rhythm is still an important treatment option for symptomatic AF. Anti-arrhythmic drugs (AADs) have had inconsistent results for the prevention of recurrent AF and have been hampered by significant adverse effects. Catheter ablation has rapidly evolved and is fast becoming an alternative for AF prevention. Although multiple treatment options exist, no single modality is effective for all patients. This review outlines best current practice for AF prevention and future perspectives, focusing on new and promising developments in antiarrhythmic drug therapy, strategies for ablation therapy, and forms of hybrid therapy that may offer improved outcomes in selected patients.