Pulsed Field or Conventional Thermal Ablation for Paroxysmal Atrial Fibrillation.

BACKGROUND: Catheter-based pulmonary vein isolation is an effective treatment for paroxysmal atrial fibrillation. Pulsed field ablation, which delivers microsecond high-voltage electrical fields, may limit damage to tissues outside the myocardium. The efficacy and safety of pulsed field ablation as compared with conventional thermal ablation are not known. METHODS: In this randomized, single-blind, noninferiority trial, we assigned patients with drug-refractory paroxysmal atrial fibrillation in a 1:1 ratio to undergo pulsed field ablation or conventional radiofrequency or cryoballoon ablation. The primary efficacy end point was freedom from a composite of initial procedural failure, documented atrial tachyarrhythmia after a 3-month blanking period, antiarrhythmic drug use, cardioversion, or repeat ablation. The primary safety end point included acute and chronic device- and procedure-related serious adverse events. RESULTS: A total of 305 patients were assigned to undergo pulsed field ablation, and 302 were assigned to undergo thermal ablation. At 1 year, the primary efficacy end point was met (i.e., no events occurred) in 204 patients (estimated probability, 73.3%) who underwent pulsed field ablation and 194 patients (estimated probability, 71.3%) who underwent thermal ablation (between-group difference, 2.0 percentage points; 95% Bayesian credible interval, -5.2 to 9.2; posterior probability of noninferiority, >0.999). Primary safety end-point events occurred in 6 patients (estimated incidence, 2.1%) who underwent pulsed field ablation and 4 patients (estimated incidence, 1.5%) who underwent thermal ablation (between-group difference, 0.6 percentage points; 95% Bayesian credible interval, -1.5 to 2.8; posterior probability of noninferiority, >0.999). CONCLUSIONS: Among patients with paroxysmal atrial fibrillation receiving a catheter-based therapy, pulsed field ablation was noninferior to conventional thermal ablation with respect to freedom from a composite of initial procedural failure, documented atrial tachyarrhythmia after a 3-month blanking period, antiarrhythmic drug use, cardioversion, or repeat ablation and with respect to device- and procedure-related serious adverse events at 1 year. (Funded by Farapulse-Boston Scientific; ADVENT ClinicalTrials.gov number, NCT04612244.).

Pulmonary vein narrowing after pulsed field versus thermal ablation.

AIMS: When it occurs, pulmonary vein (PV) stenosis after atrial fibrillation (AF) ablation is associated with significant morbidity. Even mild-to-moderate PV narrowing may have long-term implications. Unlike thermal ablation energies, such as radiofrequency (RF) or cryothermy, pulsed field ablation (PFA) is a non-thermal modality associated with less fibrotic proliferation. Herein, we compared the effects of PFA vs. thermal ablation on PV narrowing after AF ablation. METHODS AND RESULTS: ADVENT was a multi-centre, randomized, single-blind study comparing PFA (pentaspline catheter) with thermal ablation-force-sensing RF or cryoballoon (CB)-to treat drug-refractory paroxysmal AF. Pulmonary vein diameter and aggregate cross-sectional area were obtained by baseline and 3-month imaging. The pre-specified, formally tested, secondary safety endpoint compared a measure of PV narrowing between PFA vs. thermal groups, with superiority defined by posterior probability > 0.975. Among subjects randomized to PFA (n = 305) or thermal ablation (n = 302), 259 PFA and 255 thermal ablation (137 RF and 118 CB) subjects had complete baseline and 3-month PV imaging. No subject had significant (≥70%) PV stenosis. Change in aggregate PV cross-sectional area was less with PFA (-0.9%) than thermal ablation (-12%, posterior probability > 0.999)-primarily driven by the RF sub-cohort (-19.5%) vs. CB sub-cohort (-3.3%). Almost half of all PFA PV diameters did not decrease, but the majority (80%) of RF PVs decreased, regardless of PV anatomic location. CONCLUSION: In this first randomized comparison of PFA vs. thermal ablation, PFA resulted in less PV narrowing-thereby underscoring the qualitatively differential and favourable impact of PFA on PV tissue.

Clinical significance of unexplained persistent sinus tachycardia in women with structurally normal heart during the peripartum period.

BACKGROUND: Persistent sinus tachycardia (ST) is frequently encountered during pregnancy and peripartum period and its etiology often remains elusive. We sought to examine the possible association between unexplained persistent ST and obstetric outcomes. METHODS: A case control study was conducted using chart review of women admitted in labor to one of 7 hospitals of Northwell Health between January 2015 to June 2021. After excluding women with structurally abnormal hearts, we identified patients with persistent ST during the peripartum period, defined as a heart rate of more than 100 bpm for more than 48 h. A control group was created by randomly subsampling those who did not meet the inclusion criteria for sinus tachycardia. Obstetric outcomes were measured as mother's length of stay (LOS), pre-term labor (PTL), admission to the neonatal ICU (NICU), and whether she received cesarean-section (CS). RESULTS: Seventy-eight patients with persistent ST were identified, out of 141,769 women admitted for labor throughout the Northwell Health system. 23 patients with ST attributable to infection or hypovolemia from anemia requiring transfusion and 55 with unclear etiology were identified. After adjusting for age and parity, pregnant mothers with ST were 2.35 times more likely to have a CS than those without (95% CI: 1.46-3.81, p = 0.0005) and had 1.38 times the LOS (1.21- 1.56, p < 0.0001). Among mothers with ST, those with unexplained ST were 2.14 times more likely to have a CS (1.22-3.75, p = 0.008). CONCLUSION: Among pregnant patients, patients with ST have higher rates of CS.This association is unclear, however potential mechanisms include catecholamine surge, indolent infection, hormonal fluctuations, and medications. More studies are needed to explore the mechanism of ST in pregnant woman to determine the clinical significance and appropriate management.

Surface unipolar electrogram characteristics to predict site of origin of outflow tract arrhythmias using noninvasive mapping.

BACKGROUND: Noninvasive electroanatomic mapping (NIEAM) demonstrate patterns of depolarization that are useful in identifying the chamber of origin (COO) in outflow tract ventricular arrhythmias (OTVA). However, its use in predicting exact site of origin (SOO) has not yet been validated. METHODS: NIEAMs (CardioInsight, Medtronic) from 40 patients (age 62.5 ± 2.6) undergoing ablation for OTVA were reviewed for diagnostic accuracy in predicting the SOO. Earliest arrhythmia breakout and directionality of earliest instantaneous unipolar electrograms (uEGMs) on NIEAMs were evaluated subjectively by two observers for quality and amplitude. Sites with most negative earliest uEGMs on right and left ventricular outflow tracts, as well as epicardial surface were manually identified. Using NIEAM-based activation timing of the lateral mitral annulus and basal septum COO was identified for each OTVA. Predictions of SOO using NIEAMs was compared with true SOO from invasive study. NIEAMs SOO predictions were compared with subjective 12 lead electrocardiogram (ECG) review by two observers. RESULTS: Review of arrhythmia breakout and signal directionality had poor diagnostic value in predicting SOO in OTVA (50.6% and 49.4%, 56.6% and 43.4%, respectively) and underperformed compared with ECG interpretation (59.1% and 80.5%). After excluding uEGMs with poor characteristics, the uEGM with most negative amplitude at the COO was predictive of the true SOO with 96.4% sensitivity and specificity. CONCLUSION: We propose a stepwise approach when interpreting NIEAMs for OTVA where patterns of activation are evaluated first to determine the COO, followed by identification of the site with most negative amplitude instantaneous uEGM to determine SOO.

Clinical predictors of heart block during atrioventricular nodal reentrant tachycardia ablation: A multicenter 18-year experience.

BACKGROUND: Catheter ablation is considered the first-line treatment of symptomatic atrioventricular nodal reentrant tachycardia (AVNRT). It has been associated with a risk of heart block (HB) requiring a pacemaker. This study aims to determine potential clinical predictors of complete heart block as a result AVNRT ablation. METHODS: Consecutive patients undergoing catheter ablation for AVNRT from January 2001 to June 2019 at two tertiary hospitals were included. We defined ablation-related HB as the unscheduled implantation of pacemaker within a month of the index procedure. Use of electroanatomic mapping (EAM), operator experience, inpatient status, age, sex, fluoroscopy time, baseline PR interval, and baseline HV interval was included in univariate and multivariate models to predict HB post ablation. RESULTS: In 1708 patients (56.4 ± 17.0 years, 61% females), acute procedural success was 97.1%. The overall incidence of HB was 1.3%. Multivariate analysis showed that age more than 70 (odds ratio [OR] 7.907, p ≤ .001, confidence interval [CI] 2.759-22.666), baseline PR ≥ 190 ms (OR 2.867, p = .026, CI 1.135-7.239) and no use of EAM (OR 0.306, p = .037, CI 0.101-0.032) were independent predictors of HB. CONCLUSION: Although the incidence of HB post AVNRT ablation is generally low, patients can be further stratified using three simple predictors.

A standardized protocol to reliably visualize the left atrial appendage with intracardiac echocardiography: Importance of multiple imaging sites.

BACKGROUND: Currently, there is no accepted protocol for left atrial appendage (LAA) imaging with intracardiac echocardiography (ICE). OBJECTIVE: This study aimed to assess the utility of ICE to reliably visualize the entire cavity of the LAA and propose a specific procedural protocol to achieve the above objective. METHODS: We created a three-dimensional reconstruction of the LAA, using two-dimensional ICE sections obtained from three different location (the right atrium [RA], right ventricle inflow [RVI], and right ventricular outflow [RVOT]). We then compared the three-dimensional LAA reconstruction by ICE with one obtained by cardiac computed tomography angiography (CCTA) for morphological and volume differences. RESULTS: Three-dimensional reconstruction with ICE could reliably reproduce the LAA as visualized with CCTA but only when ICE sampling was performed from at least two catheter positions. There was no statistically significant difference between LAA volumes obtained with ICE and CCTA (P = 0.33). The contribution of each anatomical location to the total volume was 17% ± 16.6%, 74% ± 13.3%, and 33% ± 26% for RA, RVI, and RVOT, respectively. CONCLUSION: In comparison with CCTA, the LAA can be reliably visualized in its entity by ICE, but only if multiple imaging positions (RA, RV inflow, and RVOT) are used.

Provocation of atrial fibrillation triggers during ablation: does the use of general anesthesia affect inducibility?

INTRODUCTION: The autonomic nervous system exerts important effects upon atrial fibrillation (AF) initiation. The strategy of anesthesia used during AF ablation may impact the provocation of AF triggers. We hypothesized that the use of general anesthesia (GA) would reduce the incidence of provokable AF triggers in patients undergoing AF ablation compared to patients studied while receiving only conscious sedation (CS). METHODS AND RESULTS: We performed a prospective, case control study comparing the incidence of provokable AF triggers in a consecutive series of patients undergoing AF ablation under GA using a standard trigger induction protocol. We compared the frequency and distribution of AF triggers to a second cohort of historical controls (matched for age, gender, left atrial dimension, and AF phenotype) who underwent ablation while receiving CS. We calculated that 44 total subjects (22 patients in each group) were required to detect a 50% reduction in the incidence of AF triggers in the GA cohort. There was no difference between the 2 groups in the rate of AF trigger inducibility (77% vs. 68%, P = 0.26) or the number of triggers provoked per patient (1.2 ± 0.8 vs. 1.3 ± 0.8, P = 0.38). Patients ablated under GA required higher doses of phenylephrine during the trigger induction protocol (408.3 mg [52-600] vs. 158.3 mg [0-75]; P = 0.003), and tended to require higher doses of isoproterenol to initiate triggers (92.8 mg [20-111] vs. 63.6 mg [6-103]; P = 0.25). CONCLUSION: AF trigger induction during GA is both safe and efficacious.

Same-day contralateral implantation of a permanent device after lead extraction for isolated pocket infection.

AIMS: The purpose of this study is to examine the safety and outcomes of same-day reimplantation at the contralateral pectoral site in patients with device extraction for pocket infection but with negative blood cultures and no signs of systemic infection. METHODS AND RESULTS: Clinical and procedure-related data were retrospectively collected on 15 (11 male, mean age 77) device-dependent patients who underwent device and complete lead extraction (mean 2.5 leads per patient, mean implant duration 6.2 years) for local pocket infection, and who had a new contralateral device implanted on the same day. Temporary pacing via the femoral vein was used during extraction. The infected pocket was managed with an elliptical skin incision, debridement, full capsule resection, and primary wound closure with the end of the wound left open for a Penrose drain. Intravenous antibiotics were used prior to and through the procedure, and continued for a mean of 2 days post-procedure, with oral antibiotics used thereafter for a mean course of 2 weeks. No infections of the new device system occurred, with a mean follow-up of 39.6 months (range 12-74 months). CONCLUSION: In the setting of device erosion and isolated pocket infection without systemic or bloodstream involvement, a new contralateral device may be implanted on the same day as pocket debridement and system extraction without developing infection of the new permanent hardware. This strategy can be useful in patients with pacemaker-dependence, as an alternative to using a temporary pacing system.

Anatomically Based Ablation of Left Ventricular Summit Premature Ventricular Complexes Guided by Intracardiac Echocardiography.

Catheter ablation of premature ventricular contractions (PVCs) arising from the left ventricular summit (LVS) presents technical challenges due to the regional anatomy and frequent intramural site of origin (SOO). Intracardiac echocardiography (ICE) and the CARTOSOUND® (Biosense Webster, Diamond Bar, CA, USA) module allow the operator to directly reconstruct and visualize the dimensions and orientation of the LVS live and present it in relation to neighboring structures. We retrospectively reviewed consecutive cases between January 2021 and December 2022 of patients undergoing PVC ablation for a presumed LVS origin. The LVS was reconstructed by creating a three-dimensional representation of the left ventricular septum, using two-dimensional ICE sections. The earliest site in each chamber was tagged on the reconstructed LVS, and the presumed SOO was localized using a geometrical center point from all sites. Ablation was first delivered to the earliest site, except when the presence of coronary branches precluded radiofrequency delivery within the great cardiac vein. Of 20 patients (8 women, 62.4 ± 7.1 years old) with a presumed LVS origin, 12 had PVC recurrence within the monitoring period after the initial ablation for 192.5 ± 37.2 s at the earliest site. Among them, earliest activation was seen at the sinus of Valsalva (SoV), coronary venous system (CVS), and left ventricular endocardium (LVE) in four, six, and two patients, respectively. Using the reconstructed LVS, the anatomically closest site to the SOO was identified in the SoV, CVS, and LVE in four, two, and six cases, respectively. Throughout the study period (14.5 months; range, 9.3-19.7 months), 17 patients (85%) had complete elimination of PVCs as evaluated by 24-h event monitors at the 12-month visit. In 50% of cases, among patients in whom ablation at the earliest signal was unsuccessful, the site of successful ablation did not correlate with the second earliest signal or had no identifiable signal during initial activation mapping. The reconstructed LVS not only guided activation mapping but also identified sites proximal to the center point that had either a late activation signal, a low-amplitude signal, or no signal at all.

Clinical Significance of Supraventricular Tachycardia During Pregnancy in Healthy Women.

BACKGROUND: Supraventricular tachycardias (SVT) are the most frequently encountered arrhythmias in pregnancy with unclear clinical significance. OBJECTIVES: This study sought to report the prevalence, describe the management, and explore the association between SVT and adverse obstetric outcomes. METHODS: Cohort study of primiparous and multiparous women without history of Cesarean section (CS), and with structurally normal hearts admitted in labor. The study group consisted of women with at least 1 SVT episode during pregnancy, and the control group was randomly selected in a 4:1 ratio. RESULTS: Of 141,769 women meeting the inclusion criteria, SVT diagnosis was confirmed in 122. A total of 76 (age 33.2 ± 4.8 years) had at least 1 symptomatic and documented episode during pregnancy. In women with a known SVT diagnosis before pregnancy, medical therapy was not associated with a lower risk of SVT recurrence (OR: 1.07; 95% CI: 0.41-2.80). However, catheter ablation before pregnancy was associated with significantly lower risk of SVT recurrence (OR: 0.09; 95% CI: 0.04-0.23). Women with SVT during pregnancy had higher incidence of CS (39.5% vs 27.0%; P = 0.03), and preterm labor (PTL) (30.3% vs 8.6%; P < 0.001). Adjusting for age and parity, SVT during pregnancy was an independent predictor of CS (OR: 1.80; 95% CI: 1.03-3.10), particularly planned CS (OR: 2.89; 95% CI: 1.06-7.89) and PTL (OR: 4.37; 95% CI: 2.30-8.31). CONCLUSIONS: SVT during pregnancy is associated with increased risk for CS and PTL in healthy women. History of SVT should be sought as early as preconception counseling, and a multidisciplinary approach is warranted for both prevention and management of SVT occurrence.

In-hospital outcomes and postdischarge mortality in patients with acute coronary syndrome and atrial fibrillation.

BACKGROUND: It is unclear whether advances in management of acute coronary syndrome (ACS) and introduction of novel oral anticoagulants have changed outcomes in patients with ACS with concomitant atrial fibrillation (AF). OBJECTIVE: This study aimed to examine the incidence of AF in patients admitted for ACS and to evaluate its association with adverse outcomes, given the recent advances in management of both diseases. METHODS: Natural language processing search algorithms identified AF in patients admitted with ACS across 13 Northwell Health Hospitals from 2015 to 2021. Hierarchical generalized linear mixed modeling was used to assess the association between AF and in-hospital mortality, bleeding, and stroke outcomes; marginal Cox regression modeling was used to assess the association between AF and postdischarge mortality. RESULTS: Of 12,315 patients admitted for ACS, 3018 (24.5%) had AF with 1609 (53.3%) newly diagnosed. AF patients more commonly received anticoagulation with an oral anticoagulant (80.4% vs 12.3%) or heparin (61.9% vs 56.9%), had lengthier intensive care unit stay (72 vs 49 hours), and underwent fewer percutaneous coronary interventions (31.9% vs 53.1%). In-hospital bleeding, stroke, and mortality were higher in the AF group (15.3% vs 5.0%, 7.4% vs 2.4%, and 6.9% vs 2.1%, respectively). AF was an independent risk factor for all in-hospital outcomes (odds ratios of 2.5, 2.7, and 2.0 for bleeding, stroke, and mortality, respectively) as well as for postdischarge mortality (hazard ratio, 1.3; 95% CI, 1.2-1.5). CONCLUSION: AF is present in 25% of ACS patients and increases risk of in-hospital and postdischarge adverse outcomes. Additional data are required to direct optimal management.

Rhythm vs Rate Control Strategy for Atrial Fibrillation: A Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Rhythm control, either with antiarrhythmic drugs or catheter ablation, and rate control strategies are the cornerstones of atrial fibrillation (AF) management. Despite the increasing role of rhythm control over the past few years, it remains inconclusive which strategy is superior in improving clinical outcomes. OBJECTIVES: This study summarizes the total and time-varying evidence regarding the efficacy of rhythm- vs rate-control strategies in the management of AF. METHODS: We systematically perused the MEDLINE, CENTRAL (Cochrane Central Register of Controlled Trials), and Web of Science databases for randomized controlled trials from inception to November 2023. We included studies that compared the efficacy of rhythm control (ie, antiarrhythmic drugs classes Ia, Ic, or III, AF catheter ablation, and electrical cardioversion) and rate control (ie, beta-blocker, digitalis, or calcium antagonist) strategies among patients with nonvalvular AF. The primary outcome was cardiovascular (CV) death, whereas secondary outcomes included all-cause death, stroke, hospitalization for heart failure (HF), sinus rhythm at the end of the follow-up, and rhythm control-related adverse events. A cumulative meta-analysis to assess temporal trends and a meta-regression analysis using the percentage of ablation use was performed. RESULTS: We identified 18 studies with a total of 17,536 patients (mean age: 68.6 ± 9.7 years, 37.9% females) and a mean follow-up of 28.5 months. Of those, 31.9% had paroxysmal AF. A rhythm control strategy reduced CV death (HR: 0.78; 95% CI: 0.62-0.96), stroke (HR: 0.801; 95% CI: 0.643-0.998), and hospitalization for HF (HR: 0.80; 95% CI: 0.69-0.94) but not all-cause death (HR: 0.86; 95% CI: 0.73-1.02) compared with a rate control strategy. This benefit was driven by contemporary studies, whereas more ablation use within the rhythm control arm was associated with improved outcomes, except stroke. CONCLUSIONS: In patients with AF, a contemporary rhythm control strategy leads to reduced CV mortality, HF events, and stroke compared with a rate control strategy.

Frequent additional tachyarrhythmias in patients with inappropriate sinus tachycardia undergoing sinus node modification: an important cause of symptom recurrence.

BACKGROUND: Symptom recurrence following sinus node modification (SNM) for inappropriate sinus tachycardia (IST) remains significant despite achieving acute procedural success. The impact of non-IST tachyarrhythmias on symptom recurrence remains poorly characterized. OBJECTIVES: The objective was to determine the prevalence and nature of additional tachyarrhythmias preceding and following SNM for IST. METHODS: Consecutive patients with IST undergoing SNM at the University of Pennsylvania were studied. SNM was initially performed using an anatomic approach targeting the superolateral crista terminalis under intracardiac echocardiographic guidance and later using an electrophysiologic approach, targeting the site of the earliest right atrial activation during maximum heart rate (HR) with isoproterenol infusion. An effort was made to shift the site more caudally until a decrease of >25% in resting HR was achieved, with a blunted response to isoproterenol and flattening of the P-wave axis in leads III and aVF. Patients were followed for arrhythmia recurrence. Tachyarrhythmias were documented with electrocardiographic monitoring and then characterized during EP study. RESULTS: Thirty-three patients underwent SNM and were followed for a mean of 2.0 ± 1.5 years. During follow-up, 27% developed a non-IST tachyarrhythmia and 18% developed recurrent IST. Additionally, 42% of patients had a non-IST tachyarrhythmia prior to SNM. CONCLUSIONS: Non-IST tachyarrhythmias are common in patients with IST before and after SNM. A major reason for symptom recurrence following SNM is development of a non-IST tachyarrhythmia. These tachyarrhythmias should be detected and treated to optimize patient outcomes.

Leveraging electronic health record query to streamline adverse event reporting and protocol compliance.

Electronic medical records are increasingly being leveraged to improve the efficiency and effectiveness of clinical trials. Reporting safety data and adhering to follow-up schedules are two challenges faced by study centers conducting a large number of clinical trials led by a single principal investigator. The Lenox Hill Electrophysiology Research Department collaborated with Northwell Health's informatics department to develop a live query accessing both inpatient and outpatient data. To demonstrate the efficacy of this approach we compared the compliance rate of adverse event reporting and patient follow-up visits between a clinical trial run using this approach and a clinical trial conducted prior to use. We compared the number of out of window visits, missed visits, missed assessments, subject drop out and number of late reported adverse events between both studies. The trial run using the described query method had a marked reduction in these categories. Leveraging available informatics resources have allowed for improved efficiency, accurate adverse even reporting and improved follow-up scheduling.

Delayed cardiac repolarisation as a predictor of in-hospital mortality in patients with COVID-19.

OBJECTIVE: With the rapid influx of COVID-19 admissions during the first wave of the pandemic, there was an obvious need for an efficient and streamlined risk stratification tool to aid in triaging. To this date, no clinical prediction tool exists for patients presenting to the hospital with COVID-19 infection. METHODS: This is a retrospective cohort study of patients admitted in one of 13 Northwell Health Hospitals, located in the wider New York Metropolitan area between 1 March 2020 and 27 April 2020. Inclusion criteria were a positive SARS-CoV-2 nasal swab, a 12-lead ECG within 48 hours, and a complete basic metabolic panel within 96 hours of presentation. RESULTS: All-cause, in-hospital mortality was 27.1% among 7098 patients. Independent predictors of mortality included demographic characteristics (male gender, race and increased age), presenting vitals (oxygen saturation <92% and heart rate >120 bpm), metabolic panel values (serum lactate >2.0 mmol/L, sodium >145, mmol/L, blood urea nitrogen >40 mmol/L, aspartate aminotransferase >40 U/L, Creatinine >1.3 mg/dL and glycose >100 mg/L) and comorbidities (congestive heart failure, chronic obstructive pulmonary disease and coronary artery disease). In addition to those, our analysis showed that delayed cardiac repolarisation (QT corrected for heart rate (QTc) >500 ms) was independently associated with mortality (OR 1.41, 95% CI 1.05 to 1.90). Previously mentioned parameters were incorporated into a risk score that accurately predicted in-hospital mortality (AUC 0.78). CONCLUSION: In the largest cohort of COVID-19 patients with complete ECG data on presentation, we found that in addition to demographics, presenting vitals, clinical history and basic metabolic panel values, QTc >500 ms is an independent risk factor for in-hospital mortality.

Prevalence and clinical significance of arrhythmias during labour in women with structurally normal hearts.

OBJECTIVES: Examine the association between arrhythmias and adverse maternal outcomes in women with structurally normal hearts. METHODS: This was a case-control study of women admitted in labour to one of eight hospitals of Northwell Health from January 2015 to June 2021. After excluding women with structurally abnormal hearts, we identified women with an arrhythmic event and randomly subsampled the rest of the cohort to create a control group of 1025 patients. Multivariate analysis was performed to examine the association between arrhythmias and the incidence of caesarean section (CS), preterm labour (PTL), admission to the neonatal intensive care unit and longer length of stay (LOS). RESULTS: Of 1 41 769 women admitted in labour with a structurally normal heart, 137 had at least one arrhythmic event (0.097%). Supraventricular tachycardia (SVT), atrial fibrillation/flutter (AF) and frequent premature ventricular complexes or non-sustained ventricular tachycardia (VA) were present in 65 (0.046%), 22 (0.016%) and 46 (0.032%) women, respectively. Arrhythmia was previously diagnosed in 58.0% SVT cases but only in 9.7% AF and 8.1% VA cases. After adjusting for age, parity and comorbidities, the presence of any arrhythmia was an independent predictor of CS (OR 1.7 95% CI 1.2 to 2.5), PTL (OR 1.8, CI 1.1 to 3.0) and LOS (mean ratio 1.6, CI 1.4 to 1.8). This association was driven by presence of SVT and AF, whereas VAs were not associated with adverse outcomes. CONCLUSIONS: Arrhythmias, specifically SVT and AF, during labour in women with structurally normal heart are independently associated with adverse obstetrical outcomes.

Autonomic Neuromodulation for Atrial Fibrillation Following Cardiac Surgery: JACC Review Topic of the Week.

Autonomic neuromodulation therapies (ANMTs) (ie, ganglionated plexus ablation, epicardial injections for temporary neurotoxicity, low-level vagus nerve stimulation [LL-VNS], stellate ganglion block, baroreceptor stimulation, spinal cord stimulation, and renal nerve denervation) constitute an emerging therapeutic approach for arrhythmias. Very little is known about ANMTs' preventive potential for postoperative atrial fibrillation (POAF) after cardiac surgery. The purpose of this review is to summarize and critically appraise the currently available evidence. Herein, the authors conducted a systematic review of 922 articles that yielded 7 randomized controlled trials. In the meta-analysis, ANMTs reduced POAF incidence (OR: 0.37; 95% CI: 0.25 to 0.55) and burden (mean difference [MD]: -3.51 hours; 95% CI: -6.64 to -0.38 hours), length of stay (MD: -0.82 days; 95% CI: -1.59 to -0.04 days), and interleukin-6 (MD: -79.92 pg/mL; 95% CI: -151.12 to -8.33 pg/mL), mainly attributed to LL-VNS and epicardial injections. Moving forward, these findings establish a base for future larger and comparative trials with ANMTs, to optimize and expand their use.

Ventricular tachycardia ablation remains treatment of last resort in structural heart disease: argument for earlier intervention.

INTRODUCTION: Despite advances in ablation of ventricular tachycardia (VT), recognized toxicity of amiodarone, and potential harm of implantable cardioverter defibrillator (ICD) shocks, there appears to be reluctance to pursue catheter ablation. METHODS AND RESULTS: We tested the hypothesis that patients with structural heart disease and VT are referred late for ablation and may have worse outcomes as a result. Consecutive patients with VT and structural heart disease referred to a single center, between January 2008 and April 2009 were studied. Patients with prior VT ablations were excluded. Late referrals were defined as those with 2 or more episodes of VT, separated by at least 1 month. Ninety-eight consecutive patients were analyzed. Ninety-six percent of patients had an ICD implanted prior to ablation, 58% were in VT storm and 67% taking ≥400 mg daily of amiodarone or amiodarone intolerant (10%). Thirty-six patients fit the definition of early referral and 62 late. Overall acute procedural success was achieved in 89%. Amiodarone dose decreased from a mean and median of 559 and 400 mg daily preablation to 98 and 0 postablation (P < 0.01). Mean and median VT episodes decreased from 17 and 6 in the month preceding ablation to 1 and 0 in the 6 months following ablation (P < 0.01). In Kaplan-Meier analysis, the early referral group had superior 1-year VT free survival (P = 0.01). CONCLUSIONS: VT ablation is frequently reserved for patients receiving recurrent ICD shocks despite high dose amiodarone. Stronger consideration should be given to earlier referral for VT ablation in patients with structural heart disease.

The impact of mitral regurgitation on patients undergoing catheter ablation of atrial fibrillation.

AIMS: Mitral regurgitation (MR) causes left atrium (LA) enlargement and subsequent atrial fibrillation (AF). The presence of MR may increase recurrence rates after AF ablation. The purpose of this study was to determine the impact of MR on recurrence rates after catheter ablation of AF. METHODS AND RESULTS: We compared 95 patients with moderate or greater baseline MR (defined by MR jet area to LA area ratio ≥ 0.2) and AF undergoing ablation to 95 randomly selected patients without significant MR undergoing AF ablation. Electrocardiographic recurrence at 1-year follow-up was the primary outcome. Patients in the MR cohort had mean MR/LA ratio 0.37 vs. 0.09 in controls (P< 0.0001). Mitral regurgitation patients had larger LA dimension (4.5 vs. 4.1 cm, P< 0.0001) and more persistent AF (71 vs. 28%, P< 0.0001). Mitral regurgitation patients had higher recurrence rates than controls (61 vs. 46%, P= 0.04). The degree of MR was higher in patients with recurrence (MR/LA ratio 0.25 vs. 0.20, P= 0.03), as was LA dimension (4.5 vs. 4.1 cm, P< 0.0001). In multivariate analyses, only LA size was an independent predictor of recurrence (odds ratio 2.9 per centimetre increase in LA dimension, P= 0.005). Fifty-five percent of MR patients had normal leaflet motion, with MR likely due to atrial remodelling secondary to AF. CONCLUSION: Mitral regurgitation was associated with increased AF recurrence after AF ablation, but its impact was mediated by LA size. Left atrium size was the only independent predictor of AF recurrence. The high percentage of MR that was likely secondary to AF may have impacted our findings and deserves further study.

Indications for implantable cardioverter-defibrillator placement in ischemic cardiomyopathy and after myocardial infarction.

Dramatic reductions in the rate of sudden cardiac death due to use of implantable cardioverter-defibrillators (ICDs) have been well-established in several large randomized clinical trials including patients with left ventricular dysfunction after myocardial infarction. This article reviews the literature regarding ICD utilization in the postinfarction population, with a strong emphasis on recent clinical trials. The most current indications for, and timing of, ICD implantation postinfarction also are summarized.