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Background: The majority of data on left bundle branch area pacing (LBBAP) are on a lumenless lead. Data on the safety and effectiveness of stylet driven leads are comparatively lacking., Methods: We retrospectively analyzed 265 patients who underwent attempted LBBAP with an 7842 (Boston Scientific, Marlborough, MA) lead in the Duke University Health System between 1/1/2020 and 9/1/2023. Outcomes of interest included post-operative 7842 helix extension (≥2 helix rotations beyond the lead tip), complications, and lead parameters. A nested analysis of single and dual chamber LBBAP attempts was performed to compare outcomes among similar patients who underwent attempted LBBAP with the lumenless 3830 (Medtronic, Mineappolis, MN) lead., Results: LBBAP success with 7842 was 89.8%. Characteristics were similar among patients with (n = 238) and without (n = 27) successful implants. Helix extension was evaluable for 222 of 238 successful 7842 implants. Of evaluable leads, helix extension was complete for 174 leads (78%), and partial for 48 (21.6%). A trend towards lower dislodgement rates was observed in patients with full versus partial extension (2.9% vs. 8.3%, p = 0.0895) and the rate of full helix extension increased over time (64.1% over 24 months vs. 81.4% over 21 months, p = 0.0162). The success rate of 3830 LBBAP implants (n = 140) was 92.8% (p = 0.069 vs. 7842). At implant, R waves were similar for 7842 and 3830 leads but were greater for 7842 during follow-up (14.4 + /-0.77 vs. 11.3 + /-0.68, p = 0.004). Pacing impedances were higher with 7842 compared with 3830 at baseline (838 + /-10.44 ohms vs. 772 + /-14.58 ohms, p < 0.001) and during follow-up (652 + /-11.0 ohms vs. 513 + /-9.18 ohms, p < 0.001); similarly, 7842 pacing thresholds (@ 0.4 ms) were slightly higher at baseline (0.85 V + /-0.03 vs. 0.68 V + /-0.03, p < 0.001) and 6 months (0.95 V + /-0.03 vs. 0.80 V + /-0.03, p < 0.001) compared with those for the lumenless 3830., Conclusion: LBBAP implant success rates, complications, and pacing parameters using the 7842 lead are stable over time, and appeared overall similar to the 3830 lead. Incomplete 7842 helix extension is a modifiable risk factor for lead dislodgement., (© 2025 Wiley Periodicals LLC.)

Introduction: Accurate localization of septal outflow tract premature ventricular contractions (PVCs) is often difficult due to frequent mid-myocardial or protected origin. Compared with traditional activation mapping, CARTO Ripple mapping provides visualization of all captured electrogram data without assignment of a specific local activation time and thus may enhance PVC localization., Methods: Electroanatomic maps for consecutive catheter ablation procedures for septal outflow tract PVCs (July 2018-December 2020) were analyzed. For each PVC, we identified the earliest local activation point (EA), defined by the point of maximal -dV/dt in a simultaneously recorded unipolar electrogram, and the earliest Ripple signal (ERS), defined as the earliest point at which three grouped simultaneous Ripple bars appeared in late diastole. Immediate success was defined as full suppression of the clinical PVC., Results: Fifty-seven unique PVCs in 55 procedures were included. When ERS and EA were in the same chamber (RV, LV, or CS), the odds ratio for the successful procedure was 13.1 (95% confidence interval [CI] 2.2-79.9, p = .005). Discordance between sites was associated with a higher likelihood of needing multi-site ablation (odds ratio [OR] 7.9 [1.4-4.6; p = .020]). Median EA-ERS distance in successful versus unsuccessful cases was 4.6 mm (interquartile range 2.9-8.5) versus 12.5 mm (7.8-18.5); (p = .020)., Conclusion: Greater EA-ERS concordance was associated with higher odds of single-site PVC suppression and successful septal outflow tract PVC ablation. Visualization of complex signals via automated Ripple mapping may offer rapid localization information complementary to local activation mapping for PVCs of mid-myocardial origin., (© 2023 Wiley Periodicals LLC.)

Background: Cardiac implanted electronic device (CIED) pocket and systemic infection remain common complications with traditional CIEDs and are associated with high morbidity and mortality. Leadless pacemakers may be an attractive pacing alternative for many patients following complete hardware removal for a CIED infection by eliminating surgical pocket-related complications as well as lower risk of recurrent complications., Objective: To describe use and outcomes associated with leadless pacemaker implantation following extraction of a CIED system due to infection., Methods: Patient characteristics and postprocedural outcomes were described in patients who underwent leadless pacemaker implantation at Duke University Hospital between November 11, 2014 and November 18, 2019, following CIED infection and device extraction. Outcomes of interest included procedural complications, pacemaker syndrome, need for system revision, and recurrent infection., Results: Among 39 patients, the mean age was 71 ± 17 years, 31% were women, and the most frequent primary pacing indication was complete heart block (64.1%) with 9 (23.1%) patients being pacemaker dependent at the time of Micra implantation. The primary organism implicated in the CIED infection was Staphylococcus aureus (43.6%). Nine of the 39 patients had a leadless pacemaker implanted before or on the same day as their extraction procedure, and the remaining 30 patients had a leadless pacemaker implanted after their extraction procedure. During follow-up (mean 24.8 ± 14.7 months) after leadless pacemaker implantation, there were a total of 3 major complications: 1 groin hematoma, 1 femoral arteriovenous fistula, and 1 case of pacemaker syndrome. No patients had evidence of recurrent CIED infection after leadless pacemaker implantation., Conclusions: Despite a prior CIED infection and an elevated risk of recurrent infection, there was no evidence of CIED infection with a mean follow up of over 2 years following leadless pacemaker implantation at or after CIED system removal. Larger studies with longer follow-up are required to determine if there is a long-term advantage to implanting a leadless pacemaker versus a traditional pacemaker following temporary pacing when needed during the periextraction period in patients with a prior CIED infection., (© 2022 Wiley Periodicals LLC.)

Background: Visual confirmation of radiofrequency ablation (RFA) lesions during clinical cardiac ablation procedures could improve procedure efficacy, safety, and efficiency. It was previously shown that acoustic radiation force impulse (ARFI) imaging can identify RFA lesions in vitro and in vivo in an animal model. This is the "first-in-human" feasibility demonstration of intracardiac ARFI imaging of RFA lesions in patients undergoing catheter ablation for atrial flutter (AFL) or atrial fibrillation (AF)., Methods and Results: Patients scheduled for right atrial (RA) ablation for AFL or left atrial (LA) ablation for drug refractory AF were eligible for imaging. Diastole-gated intracardiac ARFI images were acquired using one of two equipment configurations: (1) a Siemens ACUSON S2000™ ultrasound scanner and 8/10Fr AcuNav™ ultrasound catheter, or (2) a CARTO 3™ integrated Siemens SC2000™ and 10Fr SoundStar™ ultrasound catheter. A total of 11 patients (AFL = 3; AF = 8) were imaged. ARFI images were acquired of ablation target regions, including the RA cavotricuspid isthmus (CTI), and the LA roof, pulmonary vein ostia, posterior wall, posterior mitral valve annulus, and the ridge between the pulmonary vein and LA appendage. ARFI images revealed increased relative myocardial stiffness at ablation catheter contact sites after RFA and at anatomical mapping-tagged RFA treatment sites., Conclusions: ARFI images from a pilot group of patients undergoing catheter ablation for AFL and AF demonstrate the ability of this technique to identify intra-procedure RFA lesion formation. The results encourage further refinement of ARFI imaging clinical tools and continued investigation in larger clinical trials., (© 2014 Wiley Periodicals, Inc.)

Unlabelled:  , Introduction: Cardiovascular magnetic resonance imaging (cMRI) may provide a noninvasive method to test for pulmonary vein (PV) isolation after ablation for atrial fibrillation (AF) by detecting changes in PV contraction., Methods: PV contraction (the maximal percentage change in PV cross-sectional area [CSA] during the cardiac cycle) measured 1 month before and 2 months after PV isolation was compared in 63 PVs from 16 patients with medically refractory AF. Repeat cMRI imaging and invasive catheter mapping was performed prior to repeat PV ablation in 50 PVs from 14 additional patients with recurrent AF. Contraction in PVs with sustained isolation after the initial ablation was compared to contraction in PVs with electrical reconnection to adjacent atrium. Receiver operating characteristic (ROC) curve analysis was performed to determine the optimal cutoff PV contraction value for prediction of PV-atrial reconnection after ablation. The cutoff value was then prospectively tested in 40 PVs from 12 additional patients., Results: PV contraction decreased after AF ablation (22.4 ± 10% variation in CSA before ablation vs 10.1 ± 8% variation in CSA after ablation, P < 0.00001). PVs with sustained isolation on invasive mapping contracted less than PVs with electrical reconnection to adjacent atrium (13.7 ± 10.6% vs 21.4 ± 9.3%, P = 0.021). PV contraction produced a c-index of 0.74 for prediction of PV-atrial reconnection after ablation and >17% variation in PV CSA predicted reconnection with a sensitivity of 84.6% and specificity of 66.7%., Conclusion: PV contraction is reduced by ablation. PV contraction measurement may provide a noninvasive method to test for PV isolation after ablation procedures., (© 2010 Wiley Periodicals, Inc.)

Introduction: Catheter-directed atrial fibrillation (AF) ablation is contraindicated among patients with left atrial appendage (LAA) thrombus. The prevalence of LAA thrombus among fully anticoagulated patients undergoing AF ablation is unknown., Methods and Results: We retrospectively evaluated the prevalence of LAA thrombus among 192 consecutive patients undergoing AF ablation between July 2006 and January 2009. Seven of 192 patients (3.6%) had evidence of thrombus on transesophageal echocardiogram (TEE) despite being fully anticoagulated on warfarin (international normalized ratio [INR] 2-3) for 4 consecutive weeks prior to echocardiogram. Univariate analysis demonstrated that structural heart disease, large left atrial dimension, and number of AF ablations were associated with thrombus. Three patients with thrombus had paroxysmal AF with normal LV function., Conclusion: Despite full anticoagulation, 3.6% of patients undergoing AF ablation had LAA thrombus. We recommend that all patients, regardless of LV function or left atrial size, should undergo preprocedural TEE to exclude the presence of LAA thrombus.

Introduction: Left atrial radiofrequency catheter ablation (RFA) is gaining acceptance as treatment for drug-refractory atrial fibrillation (AF). This therapy has been associated with esophageal injury and atrioesophageal fistula formation causing death., Methods: We describe 3 patients undergoing catheter ablation for AF during real-time monitoring of luminal esophageal temperature., Results: We observed heating of the esophagus during short duration low power RFA, at either the left or right pulmonary vein ostia. Cryoablation at the pulmonary vein ostium in one patient resulted in esophageal cooling. Furthermore, we observed that fluoroscopic localization of the ablation catheter at a site apparently distant from the esophagus is not adequate to assure avoidance of ablation-induced esophageal heating., Conclusions: Real-time monitoring of luminal esophageal position and temperature is feasible, enhances recognition of esophageal heating, and may add useful information beyond that provided by fluoroscopic assessment of esophageal position. There is a potential role for esophageal monitoring to help avoid thermal injury to the esophagus during catheter ablation for atrial fibrillation.

Introduction: In human type I atrial flutter, the electrophysiologic substrate is unclear. In order to determine if slow conduction is mechanistically important, we evaluated conduction velocity in the tricuspid valve-inferior vena cava (TV-IVC) isthmus, right atrial free wall, and interatrial septum in patients with and without a history of atrial flutter undergoing electrophysiologic study., Methods and Results: Nine patients with (group 1) and nine without a history of type 1 atrial flutter (group 2) were studied. Conduction time (msec) in the right atrial free wall, TV-IVC isthmus (bidirectional), and interatrial septum was measured during pacing in sinus rhythm at cycle lengths of 600, 500, 400, and 300 msec from the low lateral right atrium and coronary sinus ostium. Conduction velocity (cm/sec) was calculated by dividing the distance between pacing electrodes and sensing electrodes (cm) by the conduction time (sec). Conduction velocity was slower in the TV-IVC isthmus in group 1 (range 37 +/- 8 to 42 +/- 8 cm/sec) versus group 2 (range 50 +/- 8 to 55 +/- 9 msec) at all pacing cycle lengths (P < 0.05). However, conduction velocity was not different in the right atrial free wall or interatrial septum between groups 1 and 2. Conduction velocity was also slower in the TV-IVC isthmus than in the right atrial free wall and interatrial septum in group 1 patients, at all pacing cycle lengths (P < 0.05). Atrial flutter cycle length correlated with total atrial conduction time (r > or = 0.832, P < 0.05)., Conclusion: Slow conduction in the TV-IVC isthmus may be mechanistically important for the development of human type I atrial flutter.