Search

Several complex mechanisms, working alone, or together, initiate and maintain atrial fibrillation (AF). At disease onset, pulmonary vein-atrial triggers, producing ectopy, predominate. Then, as AF progresses, a shift toward substrate occurs, which AF also self-perpetuates. The autonomic nervous system (ANS) plays an important role as trigger and substrate. Although the efferent arm of the ANS as AF trigger is well-established, there is emerging evidence to show that (1) the ANS is a substrate for AF and (2) afferent or regulatory ANS dysfunction occurs in AF patients. These findings could represent a mechanism for the progression of AF. [ABSTRACT FROM AUTHOR]

Cardiac resynchronization therapy (CRT) is typically attempted with biventricular (BiV) pacing. One-third of patients are nonresponders. Left bundle branch area pacing (LBBAP) has been evaluated as an alternative means. The purpose of this study was to assess the feasibility and clinical response of permanent LBBAP as an alternative to BiV pacing. Of 479 consecutive patients referred with heart failure, 50 with BiV-CRT and 51 with LBBAP-CRT were included in this analysis after study exclusions. Quality-of-Life (QoL) assessments, echocardiographic measurements, and New York Heart Association (NYHA) class were obtained at baseline and at 6-monthly intervals. There were no differences in baseline characteristics between groups (all P >.05). Clinical outcomes such as left ventricular ejection fraction, left ventricular end-systolic volume, QoL, and NYHA class were significantly improved for both pacing groups compared to baseline. The LBBAP-CRT group showed greater improvement in left ventricular ejection fraction at 6 months (P =.001) and 12 months (P =.021), accompanied by greater reduction in left ventricular end-systolic volume (P =.007). QRS duration < 120 ms (baseline 160.82 ± 21.35 ms vs 161.08 ± 24.48 ms) was achieved in 30% in the BiV-CRT group vs 71% in the LBBAP-CRT group (P ≤.001). Improvement in NYHA class (P =.031) and QoL index was greater (P =.014). Reduced heart failure admissions (P =.003) and health care utilization (P <.05) and improved lead performance (P <.001) were observed in the LBBAP-CRT group. LBBAP-CRT is feasible and effective CRT. It results into a meaningful improvement in QoL and reduction in health care utilization. This can be offered as an alternative to BiV-CRT or potentially as first-line therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Sex-specific outcomes after catheter ablation (CA) for atrial fibrillation (AF) have reported conflicting findings. We examined the impact of female sex on outcomes in patients with persistent AF (PsAF) from the Catheter Ablation for Persistent Atrial Fibrillation: A Multicentre Randomized Trial of Pulmonary Vein Isolation vs PVI with Posterior Left Atrial Wall Isolation (CAPLA) randomized trial. A total of 338 patients with PsAF were randomized to pulmonary vein isolation (PVI) or PVI with posterior wall isolation (PWI). The primary outcome was arrhythmia recurrence at 12 months. Clinical and electroanatomical characteristics, arrhythmia recurrence, and quality of life were compared between women and men. Seventy-nine women (23.4%; PVI 37; PVI + PWI 42) and 259 men (76.6%; PVI 131; PVI + PWI 128) underwent AF ablation. Women were older {median age 70.4 (interquartile range [IQR] 64.8–74.6) years vs 64.0 (IQR 56.7–69.7) years; P <.001} and had more advanced left atrial electroanatomical remodeling. At 12 months, arrhythmia-free survival was lower in women (44.3% vs 56.8% in men; hazard ratio 1.44; 95% confidence interval 1.02–2.04; log-rank, P =.036). PWI did not improve arrhythmia-free survival at 12 months (hazard ratio 1.02; 95% confidence interval 0.74–1.40; log-rank, P =.711). The median AF burden was 0% in both groups (women: IQR 0.0%–2.2% vs men: IQR 0.0%–2.8%; P =.804). Health care utilization was comparable between women (36.7%) and men (30.1%) (P =.241); however, women were more likely to undergo a repeat procedure (17.7% vs 6.9%; P =.007). Women reported more severe baseline anxiety (average Hospital Anxiety and Depression Scale [HADS] anxiety score 7.5 ± 4.9 vs 6.3 ± 4.3 in men; P =.035) and AF-related symptoms (baseline Atrial Fibrillation Effect on Quality-of-Life Questionnaire [AFEQT] score 46.7 ± 20.7 vs 55.9 ± 23.0 in men; P =.002), with comparable improvements in psychological symptoms (change in HADS anxiety score −3.8 ± 4.6 vs −3.0 ± 4.5; P =.152 (change in HADS depression score −2.9 ± 5.0 vs −2.6 ± 4.0; P =.542) and greater improvement in AFEQT score compared with men at 12 months (change in AFEQT score +45.9 ± 23.1 vs +39.2 ± 24.8; P =.048). Women undergoing CA for PsAF report more significant symptoms and poorer quality of life at baseline than men. Despite higher arrhythmia recurrence and repeat procedures in women, the AF burden was comparably low, resulting in significant improvements in quality of life and psychological well-being after CA in both sexes. [ABSTRACT FROM AUTHOR]

Fidelity of electrogram sensing may reduce false alerts from an insertable cardiac monitor (ICM). The purpose of this study was to assess the effect of vector length, implant angle, and patient factors on electrogram sensing using surface electrocardiogram (ECG) mapping. Twelve separate precordial single-lead surface ECGs were acquired from 150 participants at 2 interelectrode distances (75 and 45 mm), at 3 vector angles (vertical, oblique, and horizontal), and in 2 postures (upright and supine). A subset of 50 patients also received a clinically indicated ICM implant in 1:1 ratio (Reveal LINQ [Medtronic, Minneapolis, MN]/BIOMONITOR III [Biotronik, Berlin, Germany]). All ECGs and ICM electrograms were analyzed by blinded investigators using DigitizeIt software (V2.3.3, Braunschweig, Germany). The P-wave visibility threshold was set at > 0.015 mV. Logistic regression was used to identify factors affecting P-wave amplitude. A total of 1800 tracings from 150 participants (44.5% [n = 68] female; median age 59 [35–73] years) were assessed. The median P- and R-wave amplitudes were 45% and 53% larger with vector lengths of 75 and 45 mm, respectively (P <.001 for both). The oblique orientation yielded the best P- and R-wave amplitudes, while posture change did not affect P-wave amplitude. Mixed effects modeling found that visible P-waves occur more frequently with a vector length of 75 mm than with 45 mm (86% vs 75%, respectively; P <.0001). A longer vector length improved both P-wave amplitude and visibility in all body mass index categories. There was a moderate correlation of P- and R-wave amplitudes from the ICM electrograms to those from surface ECG recordings (intraclass correlation coefficient 0.74 and 0.80, respectively). Longer vector length and oblique implant angle yielded the best electrogram sensing and are relevant considerations for ICM implantation procedures. [ABSTRACT FROM AUTHOR]

Freedom from atrial arrhythmia (AA) recurrence ≥30 seconds after pulsed field ablation (PFA) in patients with atrial fibrillation (AF) was reported in PULSED AF (Pulsed Field Ablation to Irreversibly Electroporate Tissue and Treat AF; ClinialTrials.gov Identifier: NCT04198701). AA burden may be a more clinically meaningful endpoint. The purpose of this study was to determine the influence of monitoring strategies on AA detection and AA burden association with quality of life (QoL) and health care utilization (HCU) after PFA. Patients underwent 24-hour Holter monitoring at 6 and 12 months and weekly, and symptomatic transtelephonic monitoring (TTM). AA burden post-blanking was calculated as the greater of (1) percentage of AA on total Holter time; or (2) percentage of weeks with ≥1 TTM with AA out of all weeks with ≥1 TTM. Freedom from all AAs varied by >20% when differing monitoring strategies were used. PFA resulted in zero burden in 69.4% of paroxysmal atrial fibrillation (PAF) and 62.2% of persistent atrial fibrillation (PsAF) patients. Median burden was low (<9%). Most PAF and PsAF patients had ≤1 week of AA detection on TTM (82.6% and 75.4%) and <30 minutes of AA per day of Holter monitoring (96.5% and 89.6%), respectively. Only PAF patients with <10% AA burden averaged a clinically meaningful (>19 point) QoL improvement. PsAF patients experienced clinically meaningful QoL improvements irrespective of burden. Repeat ablations and cardioversions significantly increased with higher AA burden (P <.01). The ≥30-second AA endpoint is dependent on the monitoring protocol used. PFA resulted in low AA burden for most patients, which was associated with clinically relevant improvement in QoL and reduced AA-related HCU. [ABSTRACT FROM AUTHOR]

The prevalence of atrial fibrillation (AF) and obesity are rising significantly. There is a shared association between these conditions with obesity predisposing individuals to a number of shared risk factors. In addition, obesity in itself has been shown to cause changes to the structure, function and hemodynamics of the heart. There is evidence to show that weight-loss has significant impact on AF symptoms, burden and more recently the potential to reverse the type of AF. Through risk factor management and in the case of morbid obesity, bariatric surgery, there is an improved prognosis for patients with AF and obesity. In this paper we provide a review of the current data on obesity and AF prevalence, pathogenesis and prognosis. [ABSTRACT FROM AUTHOR]

Although cardiac resynchronization therapy (CRT) is an established therapy in selected patients with heart failure with reduced ejection fraction (HFrEF), its role in orthotopic heart transplant (OHT) recipients remains understudied. We describe a case of successful CRT implantation in an OHT recipient for HFrEF and high-grade atrioventricular block. This case highlights the deliberations made given the lack of clinical trial and observational evidence for this therapy in OHT recipients. This case demonstrates the feasibility of cardiac resynchronization therapy (CRT) in an orthotopic heart transplant (OHT) recipient and adds to the scarcely reported data on the utility of CRT in this population. Given the exclusion of OHT recipients from the major CRT trials, further research is required to refine the indications for CRT implantation in this population. [ABSTRACT FROM AUTHOR]