Faculty Bibliography

BACKGROUND:Leadless pacemakers (LPs) avoid the lead- and pocket-related complications of transvenous systems, but they pace exclusively from the right ventricle (RV), and chronic RV pacing carries a recognized risk of pacing-induced cardiomyopathy (PICM). Whether implant location within the RV, a potentially modifiable factor, contributes to this risk has not been established. METHODS:Patients undergoing LP implantation with ≥50% RV pacing, pre-and post-procedural echocardiograms, and post-implant 3-dimensional radiographic imaging were included. All implants targeted the RV septum per manufacturer recommendation. PICM was defined as ≥10% decline in left ventricular ejection fraction (LVEF) to <50% without alternative cause. RESULTS:PICM developed in 20/81 patients (24.7%), with LVEF declining from 61±8% to 37±9%. Post-implant 3-dimensional radiographic imaging demonstrated inadvertent free wall implantation in 15/20 patients who developed PICM (75%) compared with 8/61 patients who did not (13%; P <0.001). Paced QRS duration was wider in patients with PICM than in those without (186±19 vs 155±13 ms, P <0.001) and discriminated free wall from non-free wall implantation with an area under the receiver operating characteristic curve (AUC) of 0.85; a QRS duration of 172 ms provided optimal discrimination. Baseline LVEF, baseline QRS duration, and comorbidity burden did not differ between groups. CONCLUSIONS:Inadvertent free wall LP implantation is strongly associated with the subsequent development of PICM. Paced QRS duration is a readily available surrogate for implant location, and targeting a paced QRS duration below approximately 172 ms at the time of implant may serve as a practical, non-invasive check on appropriate septal placement.

BACKGROUND:Systematic left atrial appendage (LAA) exclusion during mitral valve surgery reduces thromboembolic risk in patients with pre- or postoperative atrial fibrillation. Rare residual LAA-left atrial (LA) communications may occasionally occur after surgical exclusion and increase thromboembolic risk, particularly in patients not receiving anticoagulation. CASE SERIES/METHODS:Among more than 2,000 robotic mitral valve surgeries performed at NYU Langone Health from 2010 to 2025, LAA closure with LA posterior wall plication was performed using a continuous back-and-forth suture technique. We identified 4 patients with elongated residual LAA-LA communications that were occult on transesophageal echocardiography (TEE) but clearly visualized by cardiac computed tomography angiography (CCTA). TEE demonstrated persistent echolucency and color Doppler flow within the excluded LAA without a visible communication entrance. A tubular channel extending from the LAA, termed the "panhandle sign," was consistently observed. CCTA identified the communication orifices and guided successful transcatheter vascular plug closure. CONCLUSIONS:Rare elongated residual LAA-LA communications may be missed on routine TEE after LAA exclusion with LA plication. Persistent LAA flow and echolucency should prompt CCTA to detect occult communications and guide percutaneous closure. The "panhandle sign" may represent an imaging marker specific to our institutional extended-suture technique that facilitates earlier recognition.

BACKGROUND AND AIMS/OBJECTIVE:Pulsed field (PF) ablation is increasingly used to treat paroxysmal atrial fibrillation (PAF). FlexPulse (NCT06676072) was conducted to evaluate safety and effectiveness of a novel dual-energy, flexible-tip focal ablation catheter with radiofrequency and PF for treatment of symptomatic, drug-refractory PAF. METHODS:FlexPulse was a global, prospective, single arm, multicentre study. The ablation procedures targeted pulmonary vein isolation (PVI) and adjunctive ablation at operators' discretion. The primary safety endpoint was occurrence of pre-defined safety events within 7-days of any ablation procedure. The primary effectiveness endpoint was freedom from a composite of recurrent AF/atrial tachycardia/atrial flutter, repeat procedure, new use or escalation of class I/III AAD, and/or cardioversion through 12-months. RESULTS:Overall, 180 subjects underwent PAF ablation. Successful PVI was achieved in all participants. Additional non-PV ablations were performed in 37.2% (67/180) of subjects. The primary safety endpoint event rate was 1.7%. The primary effectiveness endpoint was 74.6% at 12-months, and freedom from documented AF/AFL/AT recurrence was 77.4% (92.6% without weekly transtelephonic monitoring). In 15 subjects who underwent repeat ablation after the blanking period, remapping indicated that 79.7% (47/59) of the PVs were durably isolated from the index procedures. Retrospective analysis found that workflows with PFA Index (PI) ≥30 and AutoMark distance up to 6 mm target had a 12-month freedom from AF/AFL/AT of 84.6%. CONCLUSIONS:In this trial, ablation with TactiFlex Duo in patients with symptomatic, drug-refractory PAF was safe and effective.

BACKGROUND:The value of additional lesion sets beyond pulmonary vein isolation (PVI) for atrial fibrillation (AF) ablation is unclear. However, existing studies evaluated the utility of substrate modification with conventional energy sources. There is limited data evaluating PVI with posterior wall isolation (PWI) using pulsed field ablation (PFA). METHODS:We studied consecutive cases of patients with paroxysmal AF undergoing first-time ablation with PFA between May 6, 2024 and March 10, 2025. Procedural data collected included the number of PFA applications administered, total procedure time, and major periprocedural complications. Clinical data collected included atrial tachyarrhythmia (ATA) recurrence, stroke, and major bleeding at 1-year follow-up. Outcomes were compared in patients undergoing PVI alone versus PVI plus PWI. RESULTS:A total of 249 patients were included in this study (104 PVI alone, 145 PVI plus PWI). There was no difference in ATA recurrence by Kaplan-Meier survival analysis comparing PVI alone versus PVI plus PWI (log rank test p = 0.89). When comparing PVI alone versus PVI plus PWI, there was no difference in ATA recurrence at 1 year (16% vs. 16%; p = 0.92), AF burden on continuous monitoring (2% vs. 2%; p = 0.81), total procedure time (114 vs. 107 min; p = 0.14), or major periprocedural complications (0 vs. 3; p = 0.14). CONCLUSION/CONCLUSIONS:PFA for paroxysmal AF with PVI alone or PVI plus PWI produces similar sinus rhythm maintenance without affecting procedure times or complication rates.

BACKGROUND:The optimal number of pulsed field ablation (PFA) applications during atrial fibrillation (AF) ablation is unclear. We hypothesized that the number of PFA applications would predict atrial tachyarrhythmia (ATA) recurrence rates. OBJECTIVE:To determine whether higher numbers of PFA applications would decrease ATA recurrence rates. METHODS:We studied cases of patients with AF undergoing first-time ablation with PFA between 5/6/24 and 10/7/24. All patients underwent pulmonary vein and posterior wall isolation. The primary outcome was ATA recurrence. Additional outcomes included stroke, post-procedural acute kidney injury (AKI), total procedure time, and major periprocedural complications. Univariable and multivariable analyses were performed to determine if the number of PFA applications predicted ATA recurrence. RESULTS:In a cohort consisting of 177 patients, univariable and multivariable analysis showed that the number of PFA applications split at the smallest quartile (< 57 applications) versus the largest three quartiles (≥ 57 applications) was the strongest predictor of ATA recurrence (p = 0.03). ATA recurrence at 1 year (29% vs. 8%; p < 0.01) and AF burden on continuous monitor (4% vs. 0%; p < 0.01) was higher with the standard (< 57 applications) vs higher (≥ 57 applications) PFA dose groups. When comparing the standard versus higher PFA dose groups, there was no difference in total procedure time (106 vs. 107 min; p = 0.77), major periprocedural complications (0% vs. 2%; p = 0.33), or post-procedural AKI (2% vs. 2%; p = 0.69). CONCLUSION/CONCLUSIONS:Increasing number of PFA applications is associated with reduced ATA recurrence. A higher number of PFA applications may decrease ATA recurrence without affecting procedure times or complication rate.

BACKGROUND:Intracardiac echocardiography (ICE) is widely used during electrophysiology and structural heart procedures; however, image interpretation remains operator-dependent and procedural views are not standardized. Although artificial intelligence has been increasingly applied to transthoracic and transesophageal echocardiography, applications to ICE remain limited. OBJECTIVES/OBJECTIVE:The objective of the study was to develop and evaluate Auto-Contour, a deep-learning pipeline for multistructure semantic segmentation of ICE anatomy and assess its feasibility for real-time procedural guidance. METHODS:In this retrospective multicenter study, 5,496 deidentified ICE cine loops from 249 procedures of unique patients, including routine clinical cases and the ViewFlex™ X first-in-human study, were analyzed. ICE experts classified each cine into 1 of 20 procedural views and annotated key anatomic structures, including the left atrium, left atrial appendage, pulmonary vein ostia, valves, cusps, papillary muscles, and left ventricle, at end-systole, and end-diastole, yielding 65,117 segmentations. A deep-learning segmentation model was trained using patient-level splits, standard augmentations, and early stopping. RESULTS:Segmentation performance was highest for larger cardiac chambers, with Dice scores of 0.94 for the left atrium and 0.82 for the left ventricle, and corresponding 95th-percentile Hausdorff distance values of 1.18 mm and 3.27 mm. Smaller structures also demonstrated acceptable performance, including the left atrial appendage, pulmonary veins, papillary muscles, and aortic cusps. The mean per-frame inference time was <0.03 seconds. CONCLUSIONS:Auto-Contour demonstrated robust multistructure segmentation of ICE anatomy with real-time inference, supporting prospective evaluation of artificial intelligence-assisted ICE for procedural standardization, efficiency, and safety.

BACKGROUND:Buckling of a transesophageal echocardiography (TEE) probe is a rare but potentially life-threatening complication that carries a significant risk of esophageal perforation. CASE SUMMARY/METHODS:We report 3 cases of buckled TEE probes that were promptly recognized, diagnosed, and managed using multimodal imaging. In each instance, the location of the buckled probe was confirmed with bedside imaging. Subsequently, the patient was taken to the interventional suite for advancement of the probe to the stomach under fluoroscopic guidance. Finally, the buckled TEE probe was straightened and removed successfully from the patient without difficulty. DISCUSSION/CONCLUSIONS:Early recognition of buckled TEE probes and employment of a structured, algorithmic management approach are essential to optimizing outcomes and preventing associated morbidity and mortality. TAKE HOME MESSAGES/CONCLUSIONS:Buckling of the TEE probe requires a high index of suspicion and prompt diagnosis to prevent catastrophic complications such as esophageal perforation. Advancement of the TEE probe in the stomach under fluoroscopic guidance facilitates straightening and removal of the probe without the risk of esophageal perforation.

UNLABELLED:Oral anticoagulation (OAC) remains the primary means of stroke prevention in patients with atrial fibrillation (AF). However, there are patients at greater risk of bleeding or who have experienced major bleeding, whereby long term OAC is relatively contraindicated. Additionally, up to 55% of eligible AF patients do not utilize OAC. Thus, transcatheter left atrial appendage occlusion devices (LAAOD) present an attractive alternative to mitigate stroke risk. Randomized trials have demonstrated the noninferiority of LAAOD to OAC in reducing stroke risk. However, treatment with LAAODs presents its own risks, including the risk of device-related thrombus (DRT). In this report, we describe an unusual case of a patient with a small DRT initially identified on transesophageal echocardiography (TEE) 6 weeks after implantation of a Watchman FLX (Boston Scientific, Marlborough, MA, USA) LAAOD that was appropriately treated and resolved on TEE 6 months after implantation. However, a massive late DRT recurred 2 years after implantation. This case highlights the importance of continued device monitoring for unfavorable evolution of DRT beyond the currently recommended 45-day to 1-year monitoring period, and especially after suspected thrombus resolution. Furthermore, it underlines the importance of developing newer generation LAAOD that reduces DRT risk. LEARNING OBJECTIVE/UNASSIGNED:Left atrial appendage occlusion devices can mitigate stroke risk in atrial fibrillation patients with contraindications to oral anticoagulation. However, these devices present with their own risks, including the risk of device-related thrombus (DRT). This case highlights the importance of continued device monitoring for unfavorable evolution of DRT beyond the recommended 45-day to 1-year monitoring period.

Randomized trials of ethanol infusion into the vein of Marshall (EIVOM) have shown efficacy in preventing atrial fibrillation (AF) recurrence in patients presenting for de novo ablation. The utility of EIVOM in AF patients who present for redo ablation is unclear. This meta-analysis was reported according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Medline, Scopus, and Cochrane Central Register of Controlled Trials were systematically searched to identify relevant studies. Risk of bias was assessed using the Modified Newcastle-Ottawa scale. Eligible studies reported outcomes in AF patients with previous ablation who underwent redo catheter ablation (CA) alone vs. combined redo CA and EIVOM. Five observational studies comprising 568 patients were included. When comparing combined redo CA and EIVOM vs. redo CA alone, pooled results showed no difference in freedom from arrhythmia (FFA) in all patients (risk ratio [RR] 1.13; 95% confidence interval [CI] 0.96-1.33), FFA in persistent AF patients only (RR 1.08; 95% CI 0.90-1.29), total procedure time (mean difference -0.59; 95% CI -41.04-39.85), or major periprocedural complications (RR 0.81; 95% CI 0.06-11.64). Patients with AF recurrence after ablation represent a difficult-to-treat population. Salvage therapy with combined CA and EIVOM did not improve arrhythmic outcomes compared to CA alone in AF patients who presented for redo ablation.