-
Journal of the American Heart... Dec 2019Background Persistent atrial fibrillation may lead to a higher probability of inappropriate shocks in heart failure patients with an implantable...
Feasibility and Efficacy of His Bundle Pacing or Left Bundle Pacing Combined With Atrioventricular Node Ablation in Patients With Persistent Atrial Fibrillation and Implantable Cardioverter-Defibrillator Therapy.
Background Persistent atrial fibrillation may lead to a higher probability of inappropriate shocks in heart failure patients with an implantable cardioverter-defibrillator (ICD). The aim of this study was to evaluate the impact of His-Purkinje conduction system pacing combined with atrioventricular node ablation in improving heart function and preventing inappropriate shock therapy in these patients. Methods and Results A total of 86 consecutive patients with persistent atrial fibrillation and heart failure who had indications for ICD implantation were enrolled from January 2010 to March 2018. His-Purkinje conduction system pacing with ICD and atrioventricular node ablation was attempted in 55 patients, and the remaining patients underwent ICD implantation only. Left ventricular (LV) ejection fraction, LV end-systolic volume, New York Heart Association (NYHA) classification, shock therapies, and drug therapy were assessed during follow-up. Overall, 31 patients received ICD implantation with optimal drug therapy (group 1). atrioventricular node ablation combined with His-Purkinje conduction system pacing was successfully achieved in 52 patients (group 2). During follow-up, patients in group 2 had lower incidence of inappropriate shock (15.6% versus 0%, <0.01) and adverse events (=0.011). Meanwhile, improvement in LV ejection fraction and reduction in LV end-systolic volume were significantly higher in group 2 than in group 1 (15% versus 3%, <0.001; and 40 versus 2 mL, <0.01, respectively). NYHA functional class improved in both groups from a baseline 2.57±0.68 to 1.73±0.74 in group 1 and 2.73±0.59 to 1.42±0.53 in group 2 (<0.01). Conclusions His-Purkinje conduction system pacing combined with atrioventricular node ablation is feasible and safe with a high success rate in persistent atrial fibrillation patients with heart failure and ICD indication. It can significantly reduce the incidence of inappropriate shocks and improve LV function.
Topics: Aged; Atrial Fibrillation; Atrioventricular Node; Bundle of His; Cardiac Pacing, Artificial; Case-Control Studies; Catheter Ablation; Combined Modality Therapy; Defibrillators, Implantable; Feasibility Studies; Female; Heart Failure; Humans; Male; Middle Aged; Retrospective Studies; Treatment Outcome
PubMed: 31830874
DOI: 10.1161/JAHA.119.014253 -
Medicine Aug 2020Substantial advances in cardiac pacing technology have been developed in the past decades. However, efforts to improve pacing technology to achieve physiological...
INTRODUCTION
Substantial advances in cardiac pacing technology have been developed in the past decades. However, efforts to improve pacing technology to achieve physiological electrical activity, such as with cardiac resynchronization therapy, are underway. Permanent His bundle pacing, which directly stimulates the His-Purkinje network and electrically activates both ventricles, simulates physiological electric activity in the heart, and has been considered an ideal pacing strategy to treat arrhythmias. For patients with atrial fibrillation complicated by third-degree atrioventricular block (AVB), permanent His bundle pacing is a better option than conventional right ventricular apical or septal pacing, the latter of which may be associated with risks, such as heart failure. However, His bundle pacing exhibits some shortcomings, including elevated pacing threshold, dislocation, and abnormal sensing.
CASE PRESENTATION
A 69-year-old female patient who had atrial fibrillation (AF) complicated by third-degree AVB and who was treated with permanent His bundle pacing combined with left bundle branch pacing.
DIAGNOSIS
AF complicated by third-degree AVB.
INTERVENTIONS
We used the left bundle branch as a backup pacing site to overcome any shortcomings related to permanent His bundle pacing.
OUTCOMES
The patient recovered well without any events.
CONCLUSION
We selected His bundle pacing as the primary pacing, but also used left bundle branch pacing as a backup approach. If His bundle pacing results in an increased sensing threshold, pacing threshold changes, or dislocations, left bundle branch pacing can compensate for dysfunction of permanent deficiencies in His bundle pacing, preserving physiological pacing.
Topics: Aged; Atrial Fibrillation; Atrioventricular Block; Bundle of His; Cardiac Resynchronization Therapy; Female; Humans
PubMed: 32871980
DOI: 10.1097/MD.0000000000021097 -
Kardiologia Polska 2022Left bundle branch area pacing (LBBAP) has emerged as a promising physiologic pacing strategy. Though many clinical studies have established the feasibility and safety...
BACKGROUND
Left bundle branch area pacing (LBBAP) has emerged as a promising physiologic pacing strategy. Though many clinical studies have established the feasibility and safety of LBBAP, the data for very elderly patients are lacking.
AIMS
This study aimed to assess the feasibility and safety of LBBAP in very elderly patients (≥80 years).
METHODS
Two hundred and forty consecutive patients who received LBBAP implantation were retrospectively enrolled in the present study. Inclusion criteria were patients with atrioventricular block, atrial fibrillation with a slow ventricular response, and heart failure with bundle branch block. The patients were divided into two groups: those aged ≥80 years and those aged <80 years. LBBAP implantation was successfully performed in 48 of 53 (90.6%) very elderly patients and 162 of 187 (86.5%) counterparts. In the very elderly group, the mean (standard deviation [SD]) age was 84 (3) years, mean (SD) paced QRS duration was 112.4 (9.0), and the mean (SD) stimulus to R wave peak time was 82.0 (14.2) ms. Mean (SD) pacing thresholds and mean (SD) R wave sensing were 0.61(0.21) V and 12.1 (4.7) mV at implant. Pacing parameters in very elderly patients were similar to those in their counterparts. During a median follow-up of 6 months, pacing parameters remained stable. Five patients in the very elderly group developed complications (1 with septal perforation during the procedure, 1 with pocket hematoma, 1 with pacing threshold increase, and 2 with micro lead dislodgement during follow-up).
CONCLUSION
LBBAP is safe and effective in patients ≥80 years old. LBBAP can be considered as an alternative method for delivering physiological pacing in this special population.
Topics: Aged; Aged, 80 and over; Atrial Fibrillation; Bundle of His; Cardiac Pacing, Artificial; Electrocardiography; Feasibility Studies; Humans; Retrospective Studies; Treatment Outcome
PubMed: 35167114
DOI: 10.33963/KP.a2022.0048 -
Circulation Mar 2011
Review
Topics: Arrhythmias, Cardiac; Bundle of His; Heart Conduction System; Humans; Mutation; Neuromuscular Diseases; Sinoatrial Node
PubMed: 21357845
DOI: 10.1161/CIRCULATIONAHA.110.942284 -
JACC. Clinical Electrophysiology Jun 2021
Topics: Arrhythmias, Cardiac; Bundle of His; Humans; Radiofrequency Ablation
PubMed: 34167750
DOI: 10.1016/j.jacep.2020.11.014 -
JACC. Clinical Electrophysiology Apr 2021
Topics: Bundle of His; Bundle-Branch Block; Heart Block; Humans
PubMed: 33888270
DOI: 10.1016/j.jacep.2020.12.008 -
Cardiology Journal 2023His bundle (HB) potentials vary in amplitude and duration in patients with and without slow pathways. The aim of this study was to determine the characteristics of HB...
BACKGROUND
His bundle (HB) potentials vary in amplitude and duration in patients with and without slow pathways. The aim of this study was to determine the characteristics of HB potentials and to elucidate whether they can provide clues for identification of slow pathway (SP).
METHODS
The present research prospectively studied the electrophysiological findings of 162 patients with symptomatic atrioventricular nodal reentrant tachycardia (AVNRT) due to slow-fast or fast-slow type and atrioventricular reentrant tachycardia (AVRT). Maximal HB potential (HBmax, HB with the highest amplitude) among HB cloud was recorded in both groups. For AVNRT patients, the following were measured: (1) AH interval at the "jump" during programmed atrial stimulation (A2H2, taken as a reflection of SP conduction time); (2) Distance from HBmax to the successful SP ablation site (HBmax-ABL) and from HBmax to the ostium of coronary sinus (HBmax-CSO).
RESULTS
HBmax was 0.29 ± 0.10 mV in AVNRT patients, whereas it was 0.17 ± 0.05 mV in AVRT group (p < 0.0001). Likewise, the HBmax duration was 22 ± 5 ms in AVNRT group and 16 ± 3 ms in AVRT group (p < 0.0001). The area under the receiver operating characteristic curve of HBmax amplitude in AVNRT patients was 0.86 and the optimal HBmax cut-off to predict AVNRT was ≥ 0.22 mV with a sensitivity of 0.78 and specificity of 0.84. HBmax-CSO was positively correlated with HBmax-ABL, and HBmax-ABL was positively correlated with A2H2.
CONCLUSIONS
HBmax amplitudes were higher and durations longer in patients with AVNRT, as compared to those with AVRT. Moreover, the distance between HBmax and successful ablation site was positively correlated with the SP conduction time and with the distance from HBmax to the CSO.
Topics: Humans; Tachycardia, Atrioventricular Nodal Reentry; Bundle of His; Catheter Ablation; Heart Rate; Tachycardia, Supraventricular; Electrocardiography
PubMed: 34581428
DOI: 10.5603/CJ.a2021.0107 -
JACC. Clinical Electrophysiology May 2022This study sought to examine QRS and intracardiac characteristics during selective (S) and nonselective (NS) left bundle branch pacing (LBBP) from direct left septal...
OBJECTIVES
This study sought to examine QRS and intracardiac characteristics during selective (S) and nonselective (NS) left bundle branch pacing (LBBP) from direct left septal recordings.
BACKGROUND
Criteria for S-LBBP and NS-LBBP have not been validated with intracardiac mapping.
METHODS
Pacing was performed from multielectrode Purkinje recordings below the left-sided His. S-LBBP and NS-LBBP were performed in patients with narrow QRS (n = 9), right bundle branch block (n = 3), intraventricular conduction delay (n = 5), and left bundle branch block (n = 10). QRS duration was measured from stimulus onset (QRS) and from the intrinsicoid deflection of the R-wave in V-V (QRS) to QRS end. Retrograde left bundle branch conduction was assessed by stimulus-to-retrograde His intervals.
RESULTS
Among 27 patients analyzed, 20 demonstrated both NS- and S-LBBP and were studied in paired comparisons. NS-LBBP resulted in narrower QRS compared to S-LBBP (QRS: 163 ms [interquartile range (IQR): 144-179 ms] vs 181 ms [IQR: 173-203 ms]; P < 0.001; QRS: 125 ms [IQR: 117-142 ms] vs 150 ms [IQR: 135-157 ms]; P < 0.001). Left ventricular activation time was also significantly shorter for NS-LBBP compared to S-LBBP (88 ms [IQR: 75-111 ms] vs 97 ms [IQR: 82-123 ms]; P = 0.019). Left intrahisian block was bidirectional in 10 patients with long retrograde stimulus-to-His intervals. QRS duration was significantly longer in patients with complete conduction block compared to those with intact Purkinje activation during NS-LBBP (181 ms [IQR: 162-195 ms] vs 157 ms [IQR: 139-168 ms]; P = 0.022).
CONCLUSIONS
In contrast to His-bundle pacing, S-LBBP predominantly yields a wide QRS as a result of delayed RBB synchronization, whereas NS-LBBP results in shorter QRS duration because of recruitment of the basal right ventricular septum. A wider-paced morphology of LBBP was noted in patients with complete conduction block caused by bidirectional left intrahisian block. Achievement of narrow QRS during LBBP is predicated upon capture nonselectivity or programmed atrioventricular fusion, rather than intrinsic physiologic synchrony from left bundle branch stimulation.
Topics: Atrioventricular Block; Bundle of His; Bundle-Branch Block; Cardiac Pacing, Artificial; Electrocardiography; Humans; Ventricular Septum
PubMed: 35589176
DOI: 10.1016/j.jacep.2022.01.012 -
International Journal of Cardiology Apr 2021Catheter ablation of the specialized atrioventricular junction (AVJ) with a right-side approach is an effective therapy for refractory atrial fibrillation with fast...
BACKGROUND
Catheter ablation of the specialized atrioventricular junction (AVJ) with a right-side approach is an effective therapy for refractory atrial fibrillation with fast ventricular rate. Our aim is to assess the efficacy of the procedure in a single center experience and investigate the histologic findings of AVJ after catheter ablation.
METHODS
A) Analysis of AVJ ablation efficacy in a consecutive series of patients with refractory atrial fibrillation; B) Histopathologic study of the conduction system by serial section technique and clinical-electrophysiologic correlation in four patients who underwent AVJ ablation.
RESULTS
A) Right-sided AVJ ablation was successful in all 87 consecutive patients (mean procedural time 19.2±17.9 min). Energy applications ranged from 1 to 27 (mean 5.8±5.1) with eight patients (9%) requiring > 15 applications. B) Fibrotic disruption of atrioventricular (AV) node and/or His bundle interruption was found in three cases with previous AVJ ablation. In the case requiring a left side approach, the compact AV node and common His bundle appeared undamaged whereas extensive fibrosis of the summit of the ventricular septum, branching His bundle and proximal bundle branches was found. Noteworthy, a continuity between the septal and anterior tricuspid valve leaflets was present.
CONCLUSION
Our data confirm that the ideal site for ablation of the specialized AVJ is the AV node. In selected cases with unsuccessful AV node ablation, a shift towards the His bundle is needed. A continuity between the septal and anterior leaflets of the tricuspid valve may protect the His bundle as to require multiple shocks and prolong the procedure.
Topics: Atrial Fibrillation; Atrioventricular Node; Bundle of His; Catheter Ablation; Heart Conduction System; Humans
PubMed: 33412181
DOI: 10.1016/j.ijcard.2020.12.075 -
ELife Mar 2018Mammals and birds have a specialized cardiac atrioventricular conduction system enabling rapid activation of both ventricles. This system may have evolved together with...
Mammals and birds have a specialized cardiac atrioventricular conduction system enabling rapid activation of both ventricles. This system may have evolved together with high heart rates to support their endothermic state (warm-bloodedness) and is seemingly lacking in ectothermic vertebrates from which first mammals then birds independently evolved. Here, we studied the conduction system in crocodiles (), the only ectothermic vertebrates with a full ventricular septum. We identified homologues of mammalian conduction system markers () and show the presence of a functional atrioventricular bundle. The ventricular Purkinje network, however, was absent and slow ventricular conduction relied on trabecular myocardium, as it does in other ectothermic vertebrates. We propose the evolution of the atrioventricular bundle followed full ventricular septum formation prior to the development of high heart rates and endothermy. In contrast, the evolution of the ventricular Purkinje network is strongly associated with high heart rates and endothermy.
Topics: Alligators and Crocodiles; Animals; Bundle of His; Embryo, Nonmammalian; Gene Expression Regulation, Developmental; Heart; Heart Conduction System; Heart Rate; Heart Ventricles; In Situ Hybridization; Models, Cardiovascular; Purkinje Fibers; T-Box Domain Proteins; Ventricular Septum
PubMed: 29565246
DOI: 10.7554/eLife.32120