Rates of pulmonary vein reconnection at repeat ablation for recurrent atrial fibrillation and its impact on outcomes among females and males.

BACKGROUND: Several studies have demonstrated that females have a higher risk of arrhythmia recurrence after pulmonary vein (PV) isolation for atrial fibrillation (AF). There are limited data on sex-based differences in PV reconnection rates at repeat ablation. We aimed to investigate sex-based differences in electrophysiological findings and atrial arrhythmia recurrence after repeat AF ablation METHODS: We conducted a retrospective study of 161 consecutive patients (32% female, age 65 ± 10 years) who underwent repeat AF ablation after index PV isolation between 2010 and 2022. Demographics, procedural characteristics and follow-up data were collected. Recurrent atrial tachycardia (AT)/AF was defined as any atrial arrhythmia ≥30 s in duration. RESULTS: Compared to males, females tended to be older and had a significantly higher prevalence of prior valve surgery (10 vs. 2%; P = .03). At repeat ablation, PV reconnection was found in 119 (74%) patients. Males were more likely to have PV reconnection at repeat ablation compared to females (81 vs. 59%; P = .004). Excluding repeat PV isolation, there were no significant differences in adjunctive ablation strategies performed at repeat ablation between females and males. During follow-up, there were no significant differences in freedom from AT/AF recurrence between females and males after repeat ablation (63 vs. 59% at 2 years, respectively; P = .48). CONCLUSIONS: After initial PV isolation, significantly fewer females have evidence of PV reconnection at the time of repeat ablation for recurrent AF. Despite this difference, long-term freedom from AT/AF was similar between females and males after repeat ablation.

Site-specific effects of dobutamine on cardiac conduction and refractoriness.

BACKGROUND: Isoproterenol, a non-specific beta agonist, is commonly used during electrophysiology studies (EPS). However, with the significant increase in the price of isoproterenol in 2015 and the increasing number of catheter ablations performed, the cost implications cannot be ignored. Dobutamine is a less expensive synthetic compound developed from isoproterenol with a similar mechanism to enhance cardiac conduction and shorten refractoriness, thus making it a feasible substitute with a lower cost. However, the use of dobutamine for EPS has not been well-reported in the literature. OBJECTIVE: To determine the site-specific effects of various doses of dobutamine on cardiac conduction and refractoriness and assess its safety during EPS. METHODS: From February 2020 to October 2020, 40 non-consecutive patients scheduled for elective EPS, supraventricular tachycardia, atrial fibrillation, and premature ventricular contraction ablations at a single center were consented and prospectively enrolled to assess the effect of dobutamine on the cardiac conduction system. At the end of each ablation procedure, measures of cardiac conduction and refractoriness were recorded at baseline and with incremental doses of dobutamine at 5, 10, 15, and 20 mcg/kg/min. For the primary analysis, the change per dose of dobutamine from baseline to each dosing level of dobutamine received by the patients, comparing atrioventricular node block cycle length (AVNBCL), ventricular atrial block cycle length (VABCL) and sinus cycle length (SCL), was tested using mixed-effect regression. For the secondary analysis, dobutamine dose level was tested for association with relative changes from baseline of each electrophysiologic parameter (SCL, AVNBCL, VABCL, atrioventricular node effective refractory period (AVNERP), AH, QRS, QT, QTc, atrial effective refractory period (AERP), ventricular effective refractory period (VERP), using mixed-effect regression. Changes in systolic and diastolic blood pressures were also assessed. The Holm-Bonferroni method was used to adjust for multiple testing. RESULTS: For the primary analysis there was no statistically significant change of AVNBCL and VABCL relative to SCL from baseline to each dose level of dobutamine. The SCL, AVNBCL, VABCL, AVNERP, AERP, VERP and the AH, and QT intervals all demonstrated a statistically significant decrease from baseline to at least one dose level with incremental dobutamine dosing. Two patients (5%) developed hypotension during the study and one patient (2.5%) received a vasopressor. Two patients (5%) had induced arrhythmias but otherwise no major adverse events were noted. CONCLUSION: In this study, there was no statistically significant change of AVNBCL and VABCL relative to SCL from baseline to any dose level of dobutamine. As expected, the AH and QT intervals, and the VABCL, VERP, AERP and AVNERP all significantly decreased from baseline to at least one dose level with an escalation in dobutamine dose. Dobutamine was well-tolerated and safe to use during EPS.

Lead management in patients undergoing percutaneous tricuspid valve replacement or repair: a 'heart team' approach.

Clinically significant tricuspid regurgitation (TR) has historically been managed with either medical therapy or surgical interventions. More recently, percutaneous trans-catheter tricuspid valve (TV) replacement and tricuspid trans-catheter edge-to-edge repair have emerged as alternative treatment modalities. Patients with cardiac implantable electronic devices (CIEDs) have an increased incidence of TR. Severe TR in this population can occur for multiple reasons but most often results from the interactions between the CIED lead and the TV apparatus. Management decisions in patients with CIED leads and clinically significant TR, who are undergoing evaluation for a percutaneous TV intervention, need careful consideration as a trans-venous lead extraction (TLE) may both worsen and improve TR severity. Furthermore, given the potential risks of 'jailing' a CIED lead at the time of a percutaneous TV intervention (lead fracture and risk of subsequent infections), consideration should be given to performing a TLE prior to a percutaneous TV intervention. The purpose of this 'state-of-the-art' review is to provide an overview of the causes of TR in patients with CIEDs, discuss the available therapeutic options for patients with TR and CIED leads, and advocate for including a lead management specialist as a member of the 'heart team' when making treatment decisions in patients TR and CIED leads.

Safety and Efficacy of a Novel Approach to Pulmonary Vein Isolation Using Prolonged Apneic Oxygenation.

BACKGROUND: Improved ablation catheter-tissue contact results in more effective ablation lesions. Respiratory motion causes catheter instability, which impacts durable pulmonary vein isolation (PVI). OBJECTIVES: This study sought to evaluate the safety and efficacy of a novel ablation strategy involving prolonged periods of apneic oxygenation during PVI. METHODS: We conducted a multicenter, prospective controlled study of 128 patients (mean age 63 ± 11 years; 37% women) with paroxysmal atrial fibrillation undergoing PVI. Patients underwent PVI under general anesthesia using serial 4-minute runs of apneic oxygenation (apnea group; n = 64) or using standard ventilation settings (control group; n = 64). Procedural data, arterial blood gas samples, catheter position coordinates, and ablation lesion characteristics were collected. RESULTS: Baseline characteristics between the 2 groups were similar. Catheter stability was significantly improved in the apnea group, as reflected by a decreased mean catheter displacement (1.55 ± 0.97 mm vs 2.25 ± 1.13 mm; P < 0.001) and contact force SD (4.9 ± 1.1 g vs 5.2 ± 1.5 g; P = 0.046). The percentage of lesions with a mean catheter displacement >2 mm was significantly lower in the apnea group (22% vs 44%; P < 0.001). Compared with the control group, the total ablation time to achieve PVI was reduced in the apnea group (18.8 ± 6.9 minutes vs 23.4 ± 7.8 minutes; P = 0.001). There were similar rates of first-pass PVI, acute PV reconnections and dormant PV reconnections between the two groups. CONCLUSIONS: A novel strategy of performing complete PVI during apneic oxygenation results in improved catheter stability and decreased ablation times without adverse events. (Radiofrequency Ablation of Atrial Fibrillation Under Apnea; NCT04170894).

Concomitant leadless pacing in pacemaker-dependent patients undergoing transvenous lead extraction for active infection: Mid-term follow-up.

BACKGROUND: The rate of transvenous lead extraction (TLE) due to cardiac implantable electronic device (CIED) infection continues to rise. CIED infections are associated with significant morbidity and mortality. Temporary pacing in patients with active CIED infections after TLE can be challenging. Leadless pacing has emerged as an alternative approach in this patient population. OBJECTIVE: The purpose of this study was to describe the outcomes of a strategy using concomitant leadless pacemaker implantation and TLE in patients with active infections and ongoing pacing requirements. METHODS: This study involved all leadless pacemaker implantation procedures performed during TLE between June 2018 and September 2022 in the setting of active infection. Demographic characteristics, procedural details, and clinical outcomes were analyzed. RESULTS: The study included 86 patients with indications for ongoing pacing, 60 (70%) men with mean age 77.4 ± 10.5 years, who underwent TLE and concomitant leadless pacemaker implantation in the setting of active infection. There were no procedure-related complications. Sixty-five patients (76%) had evidence of bacteremia, 80% of whom were discharged to complete their antimicrobial treatment. During a median follow-up of 163 days (interquartile range 57-403 days), there were no recurrent infections. Of the 25 deaths (29%) during the study period, 22 (88%) were unrelated to the initial infection. Nine deceased patients (36%) had methicillin-resistant Staphylococcus aureus or Candida infections, 3 of whom had persistent infection despite TLE. CONCLUSION: Leadless pacing is a safe and efficacious approach for the management of patients with pacing requirements that undergo CIED extraction in the setting of active infection.

Initial experience with stylet-driven versus lumenless lead delivery systems for left bundle branch area pacing.

INTRODUCTION: Left bundle branch area pacing (LBBP) has emerged as an alternative method for conduction system pacing. While initial experience with delivery systems for stylet-driven and lumenless lead implantation for LBBP has been described, data comparing outcomes of stylet-driven versus lumenless lead implantation for LBBP are limited. In this study, we compare success rates and outcomes of LBBP with stylet-driven versus lumenless lead delivery systems. METHODS: Eighty-three consecutive patients (mean age 74.1 ± 11.2 years; 56 [68%] male) undergoing attempted LBBP at a single institution were identified. Cases were grouped by lead delivery systems used: stylet-driven (n = 53) or lumenless (n = 30). Baseline characteristics and procedural findings were recorded and compared between the cohorts. Intermediate term follow-up data on ventricular lead parameters were also compared. RESULTS: Baseline characteristics were similar between groups. Successful LBBP was achieved in 77% of patients, with similar success rates between groups (76% in stylet-driven, 80% in lumenless, p = 0.79), and rates of adjudicated LBB capture and other paced QRS parameters were also similar. Compared with the lumenless group, the stylet-driven group had significantly shorter procedure times (90 ± 4 vs. 112 ± 31 min, p = 0.004) and fluoroscopy times (10 ± 5 vs. 15 ± 6 min, p = 0.003). Ventricular lead parameters at follow-up were similar, and rates of procedural complications and need for lead revision were low in both groups. CONCLUSION: Delivery systems for stylet-driven and for lumenless leads for LBBP have comparable acute success rates. Long-term follow-up of lead performance following use of the various delivery systems is warranted.

Temporal Changes and Clinical Implications of Delayed Peridevice Leak Following Left Atrial Appendage Closure.

OBJECTIVES: The aim of this study was to assess temporal changes and clinical implications of peridevice leak (PDL) after left atrial appendage closure. BACKGROUND: Endocardial left atrial appendage closure devices are alternatives to long-term oral anticoagulation (OAC) for patients with atrial fibrillation. PDL >5 mm may prohibit discontinuation of OAC. METHODS: Patients included in the study had: 1) successful Watchman device implantation without immediate PDL; 2) new PDL identified at 45 to 90 days using transesophageal echocardiography; 3) eligibility for OAC; and 4) 1 follow-up transesophageal echocardiographic study for PDL surveillance. Relevant clinical and imaging data were collected by chart review. The combined primary outcome included failure to stop OAC after 45 to 90 days, transient ischemic attack or stroke, device-related thrombi, and need for PDL closure. RESULTS: Relevant data were reviewed for 1,039 successful Watchman device implantations. One hundred eight patients (10.5%) met the inclusion criteria. The average PDL at 45 to 90 days was 3.2 ± 1.6 mm. On the basis of a median PDL of 3 mm, patients were separated into ≤3 mm (n = 73) and >3 mm (n = 35) groups. In the ≤3 mm group, PDL regressed significantly (2.2 ± 0.8 mm vs 1.6 ± 1.4 mm; P = 0.002) after 275 ± 125 days. In the >3 mm group, there was no significant change in PDL (4.9 ± 1.4 mm vs 4.0 ± 3.0 mm; P = 0.12) after 208 ± 137 days. The primary outcome occurred more frequently (69% vs 34%; P = 0.002) in the >3 mm group. The incidence of transient ischemic attack or stroke in patients with PDL was significantly higher compared with patients without PDL, irrespective of PDL size. CONCLUSIONS: New PDL detected by transesophageal echocardiography at 45 to 90 days occurred in a significant percentage of patients and was associated with worse clinical outcomes. PDL ≤3 mm tended to regress over time.

Reappraisal of electrocardiographic criteria for localization of idiopathic outflow region ventricular arrhythmias.

BACKGROUND: Electrocardiographic (ECG) criteria have been proposed to localize the site of origin of outflow region ventricular arrhythmias (VAs). Many factors influence the QRS morphology of VAs and may limit the accuracy of these criteria. OBJECTIVE: The purpose of this study was to assess the accuracy of ECG criteria that differentiate right from left outflow region VAs and localize VAs within the aortic sinus of Valsalva (ASV). METHODS: One hundred one patients (mean age 52 ± 16 years; 55 [54%] women) undergoing catheter ablation of right ventricular outflow tract (RVOT) or ASV VAs with a left bundle branch block, inferior axis morphology were studied. ECG measurements including V2 transition ratio, transition zone index, R-wave duration index, R/S amplitude index, V2S/V3R index, V1-3 QRS morphology, R-wave amplitude in the inferior leads were tabulated for all VAs. Comparisons were made between the predicted site of origin using these criteria and the successful ablation site. RESULTS: Patients had successful ablation of 71 RVOT and 38 ASV VAs. For the differentiation of RVOT from ASV VAs, the positive predictive values and negative predictive values for all tested ECG criteria ranged from 42% to 75% and from 71% to 82%, respectively, with the V2S/V3R index having the largest area under the curve of 0.852. Morphological QRS criteria in leads V1 through V3 did not localize ASV VAs. The maximum R-wave amplitude in the inferior leads was the sole criterion demonstrating a significant difference between right ASV, right-left ASV commissure, and left ASV sites. CONCLUSION: ECG criteria for differentiating right from left ventricular outflow region VAs and for localizing ASV VAs have a limited accuracy.

Intermittent Epicardial Lead Failure Detected Using a Continuous Ambulatory Electrocardiogram Monitor.

A 69-year-old man received epicardial pacing leads for complete atrioventricular block that occurred during a mechanical tricuspid valve replacement procedure. During follow-up, the patient reported intermittent episodes of dizziness and bradycardia. Remote transmissions and device interrogations failed to elucidate the cause of his symptoms. A continuous ambulatory electrocardiogram (ECG) monitor was used as an alternative diagnostic tool. Multiple pauses were detected by the monitor and, upon review, these events were deemed to be due to the intermittent loss of capture by the epicardial lead. Once this diagnosis was made and the malfunctioning lead was replaced, the patient's symptoms resolved. This case highlights the novel use of a continuous ambulatory ECG monitor in diagnosing intermittent loss of capture, which was not detected by remote monitoring or device interrogations.

Concomitant leadless pacemaker implantation and lead extraction during an active infection.

INTRODUCTION: The need for transvenous lead extractions due to cardiac implantable electronic device (CIED)-related infections continues to rise. Current guidelines recommend complete device removal in the setting of an active infection, which can be challenging in pacemaker-dependent patients. METHODS: We retrospectively reviewed all leadless pacemaker implants between January 2018 and November 2019 and identified a subset of patients who had undergone a concomitant CIED extraction in the setting of an active infection. Baseline characteristics, procedural details, and clinical follow-ups were recorded. RESULTS: Seventeen patients received a leadless pacemaker during the same procedure as the CIED extraction. There were no procedural complications. All patients were being treated for an active CIED infection at the time of the procedure. Fourteen patients (82.4%) were completely pacemaker-dependent and four patients (23.5%) had positive blood cultures at the time of the leadless pacemaker implantation. During a median follow-up of 143 days (interquartile range: 57, 181 days), there were no recurrent infections. CONCLUSION: Simultaneous leadless pacemaker implantation and CIED extraction are safe and feasible in the setting of an active infection. This strategy may be particularly useful in patients that are pacemaker-dependent.