BACKGROUND:The prognostic significance of blanking period arrhythmic events following extensive substrate modification ablation, such as the STABLE-SR procedure, remains inadequately defined. METHODS:In this single-center retrospective study, we analyzed data from 411 consecutive patients with non-paroxysmal atrial fibrillation (AF) undergoing first-time catheter ablation using the STABLE-SR technique. The incidence and characteristics of blanking period events (within 3 months post-ablation) were assessed. All patients were followed for 1 year to determine AF recurrence. Univariable and multivariable Logistic regression analyses were performed to identify predictors of recurrence. RESULTS:Among the 373 patients who completed follow-up, blanking period events occurred in 106 patients (28.4%). The 1-year recurrence rate was significantly higher in patients with blanking period events compared to those without (46.2% vs. 16.9%, p < 0.001). Multivariable analysis identified the presence of any blanking period event (odds ratio [OR] 2.73, 95% confidence interval [CI] 1.22-6.11, p = 0.014), adjunctive cavotricuspid isthmus ablation (OR 1.91, 95% CI 1.01-3.36, p = 0.047), and the need for end-procedural electrical cardioversion (OR 3.10, 95% CI 1.01-9.48, p = 0.047) as independent predictors of long-term recurrence. CONCLUSIONS:In patients undergoing STABLE-SR ablation for non-paroxysmal AF, arrhythmias during the blanking period are common and constitute the strongest independent predictor of 1-year recurrence. Specific procedural characteristics further stratify recurrence risk.
BACKGROUND:Prior reports of internal jugular vein (IJV) access for implantation of leadless pacemakers (LLPM) are primarily small series and for ventricular LLPM. OBJECTIVES:To describe outcomes of consecutive patients undergoing IJV access for both atrial and ventricular LLPM implantation. METHODS:This observational multicenter study included 32 consecutive patients (17 female; 69 ± 14 years; range 17-91) undergoing LLPM implantation via IJV access. Dual chamber LLPM was implanted in 16 patients, right ventricular (RV) only in 13, and right atrial (RA) only in 3. Electrical parameters were measured at implantation, 7-10 days post implantation, and at last follow-up (mean 215 ± 98 days). RESULTS:IJV access was successful in all patients. Mean procedure and fluoroscopy times were 82 ± 40 and 16 ± 9 min, respectively. RV implant required 1.3 ± 0.6 deployments with mean of 21 min and RA implant required 1.6 ± 0.9 deployments with mean of 31 min. Electrical parameters were excellent. Current of injury for the RA LLPM is the primary indicator of engagement of the atrial myocardium. Two device-related complications occurred without clinical sequelae; no late complications were observed. Fifteen patients were discharged the same day. CONCLUSIONS:IJV access for atrial and ventricular LLPM implantation is safe and effective across a broad age range and is an alternative to FV access, enabling same-day discharge and early ambulation. Elevated acute atrial capture thresholds with robust current of injury should not prompt repositioning, as thresholds significantly improve at early follow-up.
Superior vena cava (SVC) syndrome is an uncommon complication of transvenous cardiac device leads. Diagnosis may be challenging due to gradually developing and nonspecific symptoms. Furthermore, anatomical imaging does not always reflect the hemodynamic significance of venous stenosis. We retrospectively evaluated seven patients treated for lead-associated SVC syndrome. Diagnostic delay was at least ten months in five patients. Computed tomography (CT) established the diagnosis in five patients, whereas invasive pressure measurement of the right atrium and SVC was performed in two patients for diagnostic certainty. In one patient, resting pressure measurements were non-diagnostic, while exercise provoked symptoms and an increase in SVC pressure. These findings highlight that SVC syndrome is a hemodynamical disorder rather than solely an anatomical stenosis. Invasive pressure measurements, including symptom provocation, may provide important diagnostic value.
BACKGROUND:Conduction system pacing (CSP) is an emerging alternative modality of cardiac resynchronization therapy (CRT). However, not all patients obtain electrical resynchronization with CSP, there is a clinical need for reliable non-invasive predictors of response. We aimed to assess the ability of several non-invasive modalities to predict electrical resynchronization with CSP-CRT. METHODS:Patients with standard heart failure CRT indications (excluding right-bundle branch block) underwent CSP-CRT using His-bundle and left-bundle branch pacing. Electrical resynchronization was defined as a >10 ms reduction in left ventricular activation time or conversion to a physiological left ventricular activation pattern on non-invasive multi-electrode mapping. We assessed whether 12-lead ECG morphology, vector electrocardiogram (VCG) derived QRS area, Ultra High Frequency (UHF)-ECG parameters or MRI scar burden predicted electrical resynchronization. RESULTS:Thirty four patients were analyzed (mean age 69±10 years; 82% male; LVEF 30±6%; QRS duration 161±23 ms; 32% ischemic cardiomyopathy). Electrical resynchronization was achieved in 24/34 (71%; 95%CI 53-85). Strauss criteria positivity on 12-lead ECG yielded a positive predictive value (PPV) of 83% (95%CI 61-95%) and negative predictive value (NPV) of 55% (95%CI 23-83%). VCG QRS area >100µVs demonstrated PPV 100% (95% CI 81-100%) and NPV 73% (95%CI 85-100%). UHF-ECG e-DYS >50 ms gave PPV 93% (95%CI 66-100%) and NPV 47% (23%-72%); >60 ms gave PPV 90% (95%CI 66-100%) and NPV 38% (95%CI 18-62%). MRI scar burden <15% resulted in PPV 88% (95%CI 64-99%) and NPV 56% (95%CI 21-86%). Lines of propagation discontinuity on multi-electrode mapping showed PPV 100% (95%CI 85-100%) and NPV 83% (95%CI 52-98%). CONCLUSIONS:Multiple non-invasive markers, including QRS morphology, VCG QRS area, UHF-ECG e-DYS, MRI scar burden showed potential to identify patients who are likely to electrically resynchronize with CSP-CRT, although their NPVs were generally modest. Non-invasive propagation mapping had the highest PPV and NPV.
BACKGROUND:Pulmonary vein isolation (PVI) often yields suboptimal success, particularly in persistent atrial fibrillation (AF). This systematic review, frequentist meta-analysis, and Bayesian hierarchical meta-analysis evaluated whether adjunctive low-voltage area (LVA) ablation improves atrial tachyarrhythmia (ATa) outcomes, while assessing safety and potential effect modifiers. METHODS:PubMed, SCOPUS, and ScienceDirect were systematically searched for randomized controlled trials comparing PVI with versus without adjunctive LVA ablation. The primary outcome was ATa recurrence. Frequentist and Bayesian random-effects models, meta-regression, trial sequential analysis (TSA), and sensitivity analyses were performed. RESULTS:Seven RCTs comprising 1468 patients (730 receiving PVI+LVA) with a mean follow-up of 16.2±4.5 months were included. Adjunctive LVA ablation significantly reduced ATa recurrence in the frequentist analysis (RR 0.80, 95% CI 0.70-0.92; p = 0.001; I2 = 0%) and time-to-event analysis (HR 0.78, 95% CI 0.65-0.95; p = 0.012; I2 = 3.2%). Bayesian hierarchical meta-analysis demonstrated concordant findings (posterior pooled RR 0.768, 95% credible interval [CrI] 0.655-0.898) with minimal between-study heterogeneity (τ = 0.077, 95% CrI 0.004-0.241). Bayesian inference showed a 99.9% posterior probability of treatment benefit (RR<1.0), a 97.6% probability of ≥10% relative risk reduction, and a 90.8% probability of ≥15% reduction. Posterior predictive analysis yielded a 97.6% probability of benefit in a future trial. Leave-one-out and prior sensitivity analyses confirmed robust, data-driven results. Meta-regression identified no significant effect modifiers. Procedure and ablation times were not significantly prolonged, and serious complications were comparable between groups (RR 1.52, 95% CI 0.84-2.74; p = 0.169). TSA showed that 47% of the required information size had been accrued. Evidence certainty was moderate by GRADE. CONCLUSIONS:Adjunctive LVA ablation was associated with reduced ATa recurrence compared with PVI without adjunctive LVA ablation, with consistent findings across frequentist and Bayesian analyses, without increasing serious complications.
BACKGROUND:Percutaneous left atrial appendage occlusion (LAAO) is an alternative strategy for stroke prevention in patients with nonvalvular atrial fibrillation (AF) with contraindications to long-term oral anticoagulation therapy. However, evidence comparing the long-term outcomes of LAAO with those of direct oral anticoagulants (DOAC) remains limited. METHODS:A systematic search was conducted across PubMed, Scopus, and the Cochrane databases through April 2026. Co-primary outcomes were major adverse cardiovascular and cerebrovascular events (MACCE; composite of cardiac death, stroke, or systemic embolism) and net adverse clinical events (NACE; composite of MACCE and non-procedure-related bleeding). Secondary endpoints included individual components of co-primary endpoints, ischemic and hemorrhagic stroke, all-cause death, major or clinically significant bleeding (procedure + non-procedure related), and stroke or systemic embolism. The random-effects model was used to generate risk ratios (RRs) and 95% CIs. RESULTS:Four randomized controlled trials comprising 5890 AF patients and a median follow-up of 3 years were included. There was no significant difference between LAAO and DOAC therapy in the risk of MACCE (RR 1.17; 95%CI 0.96-1.41; I2 = 0%) or NACE (RR 0.89; 95%CI 0.65-1.24; I2 = 85%). Both LAAO and DOAC therapy were similar in risk of cardiac death, stroke, systemic embolism, hemorrhagic stroke, ischemic stroke, all-cause mortality, stroke or systemic embolism, and pericardial effusion. LAAO was associated with a lower risk of non-procedure-related bleeding (RR 0.60; 95%CI 0.47-0.76; I2 = 59%). CONCLUSION:LAAO demonstrated efficacy comparable to DOAC therapy in reducing the risk of MACCE, NACE, and ischemic events, while significantly reducing the risk of non-procedure-related bleeding. Our findings support a tailored approach to stroke prevention in AF, wherein LAAO serves as an effective alternative for patients with contraindications to DOAC therapy.
BACKGROUND:In Wolff-Parkinson-White (WPW) syndrome, accurate localization of accessory pathways before catheter ablation can improve procedural planning and efficiency. Several 12-lead electrocardiographic (ECG) algorithms have been proposed, but their diagnostic performance has not been consistently established. We performed a systematic review and meta-analysis to assess the accuracy of ECG-based algorithms for accessory pathway localization in manifest WPW. METHODS:Following PRISMA-DTA recommendations, PubMed, EMBASE, Cochrane CENTRAL, Web of Science, and Scopus were searched from January 1990 to January 2026. Studies enrolling adult or pediatric patients with manifest pre-excitation who underwent electrophysiological study (EPS) and catheter ablation were included. Successful localization during EPS/ablation served as the reference standard. Random-effects models were used to calculate pooled diagnostic accuracy, sensitivity, specificity, and diagnostic odds ratios (DOR). Summary receiver operating characteristic and leave-one-out sensitivity analyses were also performed. RESULTS:Seventeen studies involving 3159 patients met inclusion criteria. The pooled diagnostic accuracy of ECG algorithms was 0.91 (95% CI 0.85-0.94), although heterogeneity was substantial (I2 = 91.4%). Pooled sensitivity was 0.87 (95% CI 0.73-0.94), and pooled specificity was 0.98 (95% CI 0.95-0.99; I2 = 0%). The pooled DOR was 297.17 (95% CI 46.33-1906.19; p<0.0001). Sensitivity analyses showed stable results after sequential exclusion of individual studies. CONCLUSION:Twelve-lead ECG algorithms provide high diagnostic performance for accessory pathway localization in manifest WPW and may be useful adjuncts for pre-ablation planning, although invasive electrophysiological mapping remains essential.
INTRODUCTION:Contemporary, real-world adherence to guideline-directed transvenous cardiac implantable electronic device (CIED) extraction for patients with CIED infections in the US remains incompletely characterized. As such, we sought to evaluate national trends in CIED extraction and identify factors associated with extraction and in-hospital mortality. METHODS:A retrospective analysis of adult hospitalizations with CIED infection using the National Inpatient Sample from 2016 to 2022 was performed. National trends in extraction, factors associated with extraction, and predictors of in-hospital mortality were evaluated. Multivariable logistic regression and propensity score matching were used to estimate adjusted associations with mortality. RESULTS:Among 47,835 adults hospitalized with a CIED infection, 10,905 (22.8%) underwent extraction. National extraction rates increased modestly from 16.2% in 2016 to 23.8% in 2022 (p < 0.001) but remained low overall. Unadjusted in-hospital mortality was lower among patients who underwent extraction compared with those who did not (2.8% vs. 4.4%; p = 0.001). After adjustment, extraction was independently associated with lower mortality (OR 0.59 [95% CI, 0.44-0.80]). Higher mortality was associated with increasing age, greater comorbidity burden, and markers of acute illness severity, including acute kidney injury, cardiogenic shock, and respiratory failure. Among patients who underwent extraction, markers of acute organ failure remained associated with adjusted in-hospital mortality. CONCLUSIONS:In this contemporary, multi-payor, national cohort of patients with CIED infections, CIED extraction was independently associated with lower in-hospital mortality, but was significantly underutilized despite guideline recommendations. Mortality among those who underwent extraction was driven primarily by acute illness severity, emphasizing the need for early recognition and timely intervention. System-level strategies to improve access to extraction may help align real-world practice with guidelines.
BACKGROUND:Current of injury (COI) predicts stability and acute improvement in electrical parameters in transvenous pacing or high-voltage leads; however, the periprocedural value of this marker in leadless pacemakers (LLPs) is unknown. METHODS:From March 2021 to October 2022, 66 consecutive Micra LLP pacemaker candidates were enrolled. Electrograms (EGMs) and electrical measures were acquired immediately after the deployment and 5 min after. The primary outcomes were an acute reduction in pacing threshold and, conversely, a need for device repositioning. RESULTS:Fifty-one patients were included in the final analysis after excluding poor-quality EGMs and pacemaker-dependent cases (n = 15). COI was identified in 32 (62%). There were no differences in the initial electrical measures between the COI+ and COI- groups (p value = 0.33, 0.37, 0.89 for impedance, pacing threshold, and sensing, respectively). Notably, the capture threshold significantly improved only in the COI+ group within 5 min (p = 0.002). A subgroup analysis of COI+ revealed that the saddleback type of injury (Type 2) was associated with a more significant acute reduction in the capture threshold (p = 0.02). Repositioning occurred in three subjects, and acute dislodgment at the tug-test occurred in two patients, all from the COI- group. CONCLUSIONS:COI is associated with an acute improvement of capture threshold, particularly when a Type 2 pattern is noted. The absence of injury, in contrast, could reflect inadequate fixation and a need for repositioning.
BACKGROUND:Remote monitoring (RM) enables convenient follow-up of patients with cardiac implantable electronic devices. In remote-only monitoring (RM-only), in-person visits are only scheduled if needed based on RM findings. This study evaluated the feasibility and safety of medium-term RM-only of pacemaker (PM) patients. METHODS:All patients with Biotronik PM were included in the analysis. Data on the number and causes of additional in-office device interrogations, actions due to the transmissions, hospitalizations and performance of RM were collected from a large cohort of PM patients followed by RM-only. RESULTS:In total, 606 patients (302 females) with a mean age of 78 ± 12 years were included in the analysis. During the mean follow-up of 2.8 years, 445 additional in-office device interrogations were made in 287 patients (0.3 interrogations/year), and in 110 (25%) of these cases, changes to device programming were made. In a subgroup analysis of 100 patients with at least one year of prior appointment-based device monitoring, the need for in-office visits was 6.9 times higher per follow-up year than in RM (IRR = 6.9, 95% CI 4.9-9.9; p < 0.001). The hospitalization rate in the entire cohort during RM was 0.3 / year with no difference in the rate of hospitalizations between the two monitoring methods (IRR 1, 95% CI 0.8-1.4, p = 0.8). The success of daily transmissions was 91.7%. CONCLUSION:Our real-world data indicate that RM-only may be a viable option for long-term follow-up of PM patients. Portions of this manuscript contain text overlap with our previously published work because they describe the same methodology and standard clinical procedures. All overlapping material has been appropriately cited, and no previously published data, results, or conclusions have been duplicated without attribution.
BACKGROUND:The Micra leadless pacemaker (LPM) should ideally be implanted in the septal location to enhance safety. However, the probability of accurate septal implantation and its predictive factors have not been fully elucidated. METHODS:Eighty-three consecutive patients who underwent computed tomography (CT) following LPM implantation were included. The ventricular septum was targeted using a standard fluoroscopic-guided transfemoral approach. The LPM implantation site was classified as septal or non-septal based on CT findings. The septal-inferior vena cava (IVC) angle was evaluated as a patient-specific anatomical parameter representing the relationship between IVC inflow and the ventricular septum. RESULTS:Accurate septal implantation was achieved in 44 patients (53.0%). The septal-IVC angle was significantly larger in the septal group than in the non-septal group (13.1 ± 11.6° vs. 2.7 ± 10.6°, p < 0.001). Multivariate logistic regression analysis indicated that the septal-IVC angle (odds ratio, 1.09; 95% confidence interval, 1.03-1.14; p = 0.002) was independently associated with the incidence of septal implantation. The optimal cutoff value for the septal-IVC angle was 6°, with a sensitivity of 77.3% and a specificity of 66.7% for predicting septal implantation. There were no cases of cardiac tamponade or pericardial effusion. No significant differences in long-term outcomes, including all-cause mortality, cardiac mortality, and heart failure hospitalization, were observed between the two groups. CONCLUSIONS:Accurate septal implantation was observed in 53.0% of patients who had undergone LPM implantation with the standard femoral approach. A larger septal-IVC angle was associated with accurate septal implantation.
INTRODUCTION:Brugada syndrome epicardial RVOT ablation reduces VF, but procedural endpoints remain debated. Automated fractionation maps are often interpreted as scattered points, which may reflect artifacts. OBJECTIVES:We propose Islands of Fractionation (IOF), a framework comparing EnSite X fractionation count settings against voltage-defined lesion-effect reference region. METHODS:This case series included six Brugada syndrome patients undergoing epicardial substrate ablation. Mapping was performed in sinus rhythm using EnSite X with an Advisor HD Grid catheter. Automated fractionation maps were generated with the EnSite X CFE-count algorithm using refractory settings of 14 and 20 ms. Abnormal points were defined as fractionation count ≥3; lesion-effect reference region was defined by voltage change (pre >0.5 mV, post <0.3 mV). Island overlap was quantified using DBSCAN clustering and mesh-based area estimation. RESULTS:IOF revealed a consistent coverage-parsimony trade-off between refractory settings. The 14-ms setting produced broader islands with higher reference-region coverage (median overlap 84.6% [IQR 80.8-93.7]) but larger extraneous mapped area (up to 72.9 cm2). The 20-ms setting produced more compact islands with markedly reduced extraneous area (0.0-34.8 cm2) but lower coverage (59.9% [IQR 37.2-74.7]). In parallel, fractionation burden within the ablated region decreased substantially after ablation in both settings (median total burden reduction 86% vs 93%), supporting lesion-effect concordance of automated fractionation metrics. CONCLUSION:IOF provides an island-based framework for interpreting automated fractionation mapping and describing its spatial concordance with lesion-effect regions. In this retrospective series, 14 ms favored broader coverage, whereas 20 ms favored greater parsimony.
OBJECTIVE:To evaluate the impact of anterior versus lateral/posterolateral left ventricular (LV) lead positioning on clinical and echocardiographic outcomes in patients undergoing cardiac resynchronization therapy (CRT). METHODS:A systematic review and meta-analysis were conducted in accordance with PRISMA guidelines. Electronic databases, including PubMed, Embase, Web of Science, and Cochrane Library, were searched for studies assessing LV lead position and CRT outcomes. Studies comparing anterior with lateral or posterolateral LV lead placement were included. Data were extracted on mortality, CRT response, and left ventricular ejection fraction (LVEF). Pooled effect estimates were calculated using a random-effects model. RESULTS:A total of six studies were included in the qualitative synthesis, with five studies eligible for quantitative meta-analysis. Lateral or posterolateral LV lead positioning was associated with significantly reduced mortality compared to anterior positioning (pooled HR 0.74, 95% CI 0.63-0.86). CRT response rates were significantly higher with lateral/posterolateral positioning (pooled OR 1.40, 95% CI 1.17-1.67). Additionally, patients with optimal lead placement demonstrated greater improvement in LVEF (mean difference 4.0%, 95% CI 1.84-6.16). Heterogeneity across studies was low. CONCLUSION:Lateral or posterolateral LV lead positioning is associated with improved survival, higher CRT response rates, and enhanced reverse remodeling compared to anterior lead placement. Optimizing LV lead position may enhance clinical outcomes in patients undergoing CRT.
BACKGROUND:Permanent pacemaker (PPM) battery longevity impacts downstream procedures, patient outcomes, and healthcare costs. OBJECTIVES:To measure and predict PPM battery longevity in routine, clinical practice. METHODS:We analyzed a nationwide, multicenter, remote monitoring dataset (PaceMate) to evaluate PPM battery longevity from 2007 to 2023. Multivariable models identified factors associated with replacement interval (RI) across device types and manufacturers. We also compared observed versus expected battery longevity and assessed differences between newer and older generation pacemakers. RESULTS:We included 58,395 devices from 47 sites: 5803 single-chamber transvenous, 1637 single-chamber leadless, 45,293 dual-chamber transvenous, 1759 RV/LV-only CRT pacemakers, and 3903 full CRT-P systems (1888 reaching RI). Median observed battery longevity for the 1493 dual chamber transvenous pacemakers that reached RI ranged from (103 months for BSX to 125 months for MDT and BIO), with similar trends after adjustment (p<0.001). There was variability in median battery longevity across manufacturers for other device types: 105-122 months for single-chamber transvenous, 61-96 months for RV/LV-only CRT pacemakers, and 77-93 months for full CRT-P systems. Compared with older generators, those implanted in 2022-23 demonstrated improved estimated battery longevity for Medtronic devices but decreased for Abbott (no significant change for Boston Scientific). CONCLUSIONS:Observed pacemaker battery longevity, based on nearly 2000 devices reaching ERI, varies substantially by manufacturer and device type, without consistent improvement for newer devices. Device-based estimates of remaining longevity show manufacturer-specific variability and are influenced by programming and utilization, highlighting the need for individualized expectations in clinical practice. CONDENSED ABSTRACT:Permanent pacemaker (PPM) battery longevity is clinically impactful and not well described in routine, clinical practice. We quantified pacemaker battery performance in a nationwide, multicenter, remote monitoring dataset, including 58,395 devices. Pacemaker battery longevity varies by manufacturer and device type, without consistent improvement for newer devices. Manufacturer-specific accuracy of battery longevity estimates and differences in device programming and utilization highlight the need for individualized expectations in clinical practice.
BACKGROUND:Reliable catheter-tissue apposition is important for effective pulmonary vein isolation using pulsed field ablation. The contact index, derived from real-time impedance rise on the EnSite X mapping system, may provide an objective surrogate for catheter contact; however, its utility with the PulseSelect catheter remains insufficiently defined. METHODS:In this single-center pilot study, patients with paroxysmal atrial fibrillation undergoing pulmonary vein isolation with the PulseSelect catheter under general anesthesia were evaluated. High-resolution transesophageal echocardiography was used as the reference standard to classify electrode-level catheter apposition as contact or non-contact. Contact index values from electrodes 3-7 were paired with transesophageal echocardiography findings, and receiver operating characteristic curve analysis was performed. RESULTS:A total of 316 paired imaging-electrical data points were analyzed. Interobserver agreement for transesophageal echocardiography-based contact assessment was excellent (Cohen's κ = 0.86). Contact index values were higher at contact than non-contact segments. A contact index cutoff of 10% yielded an area under the curve of 0.864, with 76.1% sensitivity and 82.9% specificity. In the central electrodes 4-6, the area under the curve was 0.871, with 80.1% sensitivity and 81.2% specificity. CONCLUSIONS:Contact index was associated with transesophageal echocardiography-confirmed catheter-tissue apposition during pulsed field ablation using the PulseSelect catheter. A 10% threshold may be a useful candidate reference for real-time apposition assessment, requiring validation in larger studies.
Radiofrequency-powered and inductively coupled semi-implanted pacemakers offered an early alternative to battery-powered implantable pulse generators by transferring energy across intact skin to a small, implanted receiver. This review summarizes key clinical and engineering developments from the first reported radiofrequency-powered pacing in 1959 through subsequent refinements and commercial implementations, including the Cutler-Hammer and Cordis Transicor RF systems, and it places these efforts alongside the Abrams/Lightwood inductively coupled device commercialized by Joseph Lucas Ltd. These systems reduced implanted size and allowed external servicing, but they imposed major human factors and safety constraints because pacing depended on correct placement and continuous operation of external hardware. As implantable-grade batteries, hermetic packaging, and lead technology improved, fully implantable pacemakers became clinically dominant. The historical experience nonetheless established durable principles of transcutaneous energy transfer that continue to inform modern externally powered implantable therapies where brief interruptions are clinically tolerable.
Intracardiac echocardiography (ICE) is an alternative to transesophageal echocardiography for imaging guidance during left atrial appendage occlusion (LAAO) in patients with atrial fibrillation with intolerance to long-term oral anticoagulation. This narrative review synthesizes contemporary evidence on ICE-guided LAAO. Across observational studies, ICE provides real-time high-resolution imaging enabling accurate trans-septal puncture, device sizing, and deployment under conscious sedation. Procedural success, peri-device leak, and device-related thrombus rates appear comparable between ICE- and TEE-guided LAAO, while ICE may also shorten fluoroscopy time and avoid general anesthesia. Challenges with ICE include operator learning curve, need for additional venous access and intracardiac catheter manipulation, that may add to risks like pericardial effusions, vascular complications and higher costs. Emerging 3D/4D ICE and artificial-intelligence-integrated computed tomographic planning may improve efficiency and allow for combined ablation and LAAO procedures. Further randomized controlled trials and cost-effectiveness studies are needed to define the role of ICE-first approach.
INTRODUCTION:SGLT2 inhibitors (SGLT2i) reduce heart failure events across the ejection fraction spectrum, but their association with device-adjudicated ventricular arrhythmias in real-world primary-prevention ICD recipients remains poorly characterized. METHODS AND RESULTS:In a prospectively maintained primary-prevention ICD registry (n = 62; January 2021 onward), 36 patients (58%) were receiving SGLT2i at implantation. The primary endpoint was first appropriate ICD shock for sustained ventricular tachyarrhythmia; death without prior shock was the pre-specified competing event. Cumulative incidence functions were estimated by the Aalen-Johansen method. Over a median follow-up of 752 days, 22 first appropriate shocks occurred. SGLT2i-treated patients had more advanced structural disease (median LVEF 31% vs. 51%) and lower baseline arrhythmic burden (NSVT 36% vs. 69%) than untreated patients. Cumulative incidence of appropriate shock differed significantly between groups (Gray test p = 0.008). In a cause-specific Cox model adjusted for LVEF and amiodarone use, SGLT2i was associated with a lower hazard of appropriate shock (HR 0.34; 95% CI 0.13-0.91; p = 0.031), confirmed by Fine-Gray subdistribution analysis (sHR 0.36; 95% CI 0.13-0.99; p = 0.047). Results were consistent in an HFrEF sub-cohort (LVEF 35% or less; HR 0.24; 95% CI 0.06-0.92; p = 0.037). Adjustment for baseline NSVT attenuated the association to non-significance (HR 0.43; p = 0.12), reflecting confounding by arrhythmic substrate. CONCLUSION:In this single-center competing-risk analysis, SGLT2i use at ICD implantation was associated with fewer device-adjudicated arrhythmic events. Whether this reflects direct electrophysiological modification or favorable patient selection requires confirmation in larger cohorts.
ABSTRACT Atrial fibrillation (AF) is the most prevalent sustained arrhythmia worldwide. Acute myocardial infarction (AMI) is closely intertwined with AF through a bidirectional relationship: pre‐existing AF is associated with increased risk of AMI, while AMI predisposes to new‐onset atrial fibrillation (NOAF). This narrative review synthesizes evidence on the global burden of AF in the setting of AMI: pre‐existing AF, NOAF following AMI, and the prognostic implications of AF in AMI, encompassing the ‘past, present and future’ of AF in AMI. Pre‐existing AF is present in 3%–4% of patients with AMI and has demonstrated an independent association with acute coronary syndromes, mediated by systemic inflammation, prothrombotic states, demand ischemia, and coronary thromboembolism. NOAF complicates 5%–20% of AMI cases, with peak onset within the first six months. Predictive factors include age, comorbidities such as chronic kidney disease, markers of inflammation (including systemic immune‐inflammation index and hs‐CRP), neurohormonal activation (NT‐proBNP), echocardiographic parameters of diastolic dysfunction and left atrial strain, and electrocardiographic features such as QRS fragmentation. Multiple predictive models for NOAF have been developed with varying discriminatory performance. Emerging research suggests that machine learning may provide superior risk stratification, though further study is needed. AF in the context of AMI confers substantially increased risk of mortality, stroke, bleeding, and heart failure, with NOAF showing particularly strong prognostic significance. Improved recognition of predictive markers, alongside development of tailored prognostic models, is essential to guide antithrombotic therapy and optimize outcomes in this high‐risk population.
