Late Outcome and Predictors of Adverse Events Related to the Implantation of a Permanent Pacemaker in Patients with Isolated Congenital Atrioventricular Block

Clinical Characteristics of Patients with Tetralogy of Fallot who Underwent an Invasive Procedure for Arrhythmias

Introduction: Tetralogy of Fallot (TOF) is a cyanotic congenital heart disease that has an incidence of sudden cardiac death of 0.2% per year, being arrhythmias the main cause of its occurrence. Objective: To compare characteristics of TOF patients referred for electrophysiological study (EPS) against those that were not (No-EPS). Method: Retrospective cohort with 215 patients (57.2% men; age = 29 ± 4) with corrected TOF (median of three years, ranging from 0.33 to 51) that underwent EPS between 2009-2020. The primary outcome was composed of death, implantable cardiac defibrillator (ICD) requirement and hospitalization. Results: Pre-syncope (EPS = 4.7%, No-EPS = 0%; p = 0.004), syncope (EPS = 7.1%, No-EPS = 1.7%; p = 0.056) and palpitations (EPS = 31%, No-EPS = 5.8%; p < 0.001) were symptoms that justified electrophysiological investigation. ICD was implanted in 24% of EPS and 0.6% of No-EPS (p=0.001). Twenty-six percent of the EPS group presented non-sustained ventricular tachycardia, while 0% in No-EPS (p = 0.012). The EPS group had more atrial fibrillation or atrial Flutter (35.7% vs. 6.9%; p < 0.001). The EPS patients had a wider QRS duration than the no-EPS group (171.12 ± 29.52 ms vs. 147 ± 29.77 ms; p < 0.001). Also, 26.2% of EPS performed ablation to correct macroreentrant atrial tachycardias. The incidence of primary outcome (death + ICD requirement + hospitalization) was higher in patients in the EPS group compared to the No-EPS group (p = 0.001). However, the total of seven deaths occurred during the clinical follow-up, but without differences between the groups (EPS = 4.7% vs. No-EPS = 2.8%; p = 0.480). Conclusion: EPS group had a profile of greater risk, more complex heart disease, and a greater occurrence of the primary outcome when compared to the No-EPS group.

Epicardial Pacemaker in Neonates and Infants: Is There a Relationship Between Patient Size, Device Size, and Wound Complicatıon?

We aimed to investigate the complications after epicardial pacemaker (PM) implantation in neonates and infants and their relationship with factors such as device size and patient size. Between May 2010 and July 2018, 55 patients under 1 year of age who underwent epicardial PM placement were retrospectively evaluated. PM-related complications requiring rehospitalization were determined as wound site problems requiring surgical intervention, battery pocket infection, battery pocket dehiscence without infection, PM removal, relocation of the PM system, and replacement of the PM system with another system. The patients were divided into three groups: < 3 kg, 3-5 kg and > 5 kg. Fifty-five patients underwent PM implantation, 43 (78.2%) because of postoperative atrioventricular block (AVB), 10 (18.2%) because of congenital AVB, and two (3.6%) with diagnoses of c-TGA and AVB. Five (9%) patients incurred 18 complications. No statistically significant difference was observed in complication development between the groups (p > 0.05). Single- or dual-chamber device implantation did not affect complication development (p > 0.05). Despite the role of factors such as low weight, low age, and device volume in the development of wound complications, the relationship between these factors and complications is not statistically significant. Therefore, our results are encouraging in terms of the use of dual-chamber PMs instead of single-chamber ones in heart diseases in which AV synchronization is important.

New-onset left bundle branch block after transcatheter aortic valve replacement is associated with adverse long-term clinical outcomes in intermediate-risk patients: an analysis from the PARTNER II trial

Aims

Transcatheter aortic valve replacement (TAVR) is now an established therapy for intermediate-risk surgical candidates with symptomatic, severe aortic stenosis. The clinical impact of new-onset left bundle branch block (LBBB) after TAVR remains controversial and has not been studied in intermediate-risk patients. We therefore sought to analyse outcomes associated with new LBBB in a large cohort of intermediate-risk patients treated with TAVR.

Methods and results

A total of 2043 patients underwent TAVR in the PARTNER II trial and S3 intermediate-risk registry and survived to hospital discharge. Patients were excluded from the current analysis due to baseline conduction disturbances, pre-existing permanent pacemaker (PPM), and new PPM during the index hospitalization. Clinical outcomes at 2 years were compared between patients with and without persistent, new-onset LBBB at hospital discharge, and multivariable analysis was performed to identify predictors of mortality. Among 1179 intermediate-risk patients, new-onset LBBB at discharge occurred in 179 patients (15.2%). Patients with new LBBB were similar to those without except for more frequent diabetes and more frequent treatment with SAPIEN 3 vs. SAPIEN XT. At 2 years, new LBBB was associated with increased rates of all-cause mortality (19.3% vs. 10.8%, P = 0.002), cardiovascular mortality (16.2% vs. 6.5%, P < 0.001), rehospitalization, and new PPM implantation. By multivariable analysis, new LBBB remained an independent predictor of 2-year all-cause [hazard ratio (HR) 1.98, 95% confidence interval (95% CI) 1.33, 2.96; P < 0.001] and cardiovascular (HR 2.66 95% CI 1.67, 4.24; P < 0.001) mortality. New LBBB was also associated with worse left ventricular systolic function at 1 and 2-year follow-up.

Conclusions

In a large cohort of intermediate-risk patients from the PARTNER II trial and registry, persistent, new-onset LBBB occurred in 15.2% of patients without baseline conduction disturbances or pacemaker. New LBBB was associated with adverse clinical outcomes at 2 years, including all-cause and cardiovascular mortality, rehospitalization, new pacemaker implantation, and worsened left ventricular systolic function.

Clinical Trial Registration

ClinicalTrials.gov #NCT01314313 and NCT03222128.