Pacing-induced cardiomyopathy (PICM) is among the most common right ventricular pacing complications. Upgrading to cardiac resynchronization therapy (CRT) is the recommended treatment option. Conduction system pacing with His bundle pacing (HBP) has the potential to restore synchronous ventricular activation and can be an alternative to biventricular pacing (BVP). Patients with PICM scheduled for a system upgrade to CRT were included in the prospective cohort study. Either HBP or BVP was used for CRT. Electrocardiographic, clinical, and echocardiographic measurements were recorded at baseline and six-month follow-up. HBP was successful in 44 of 53 patients (83%). Thirty-nine patients with HBP and 22 with BVP completed a 6-month follow-up. HBP led to a higher reduction in QRS duration than BVP, 118.3 ± 14.20 ms vs. 150.5 ± 18.64 ms, p < 0.0001. The improvement in New York Heart Association (NYHA) class by one or two was more common in patients with HBP than those with BiV (p = 0.04). Left ventricular ejection fraction (LVEF) improved in BVP patients from 32.9 ± 7.93% to 43.9 ± 8.07%, p < 0.0001, and in HBP patients from 34.9 ± 6.45% to 48.6 ± 7.73%, p < 0.0001. The improvement in LVEF was more considerable in HBP patients than in BVP patients, p = 0.019. The improvement in clinical outcomes and left ventricle reverse remodeling was more significant with HBP than BVP. HBP can be a valid alternative to BVP for upgrade procedures in PICM patients.

Aims: Electromechanical coupling in patients receiving cardiac resynchronization therapy (CRT) is not fully understood. Our aim was to determine the best combination of electrical and mechanical substrates associated with effective CRT.Methods and results: Sixty-two patients were prospectively enrolled from two centres. Patients underwent 12-lead electrocardiogram (ECG), cardiovascular magnetic resonance (CMR), echocardiography, and anatomo-electromechanical mapping (AEMM). Remodelling was measured as the end-systolic volume (ΔESV) decrease at 6 months. CRT was defined effective with ΔESV ≤ −15%. QRS duration (QRSd) was measured from ECG. Area strain was obtained from AEMM and used to derive systolic stretch index (SSI) and total left-ventricular mechanical time. Total left-ventricular activation time (TLVAT) and transeptal time (TST) were derived from AEMM and ECG. Scar was measured from CMR. Significant correlations were observed between ΔESV and TST [rho = 0.42; responder: 50 (20–58) vs. non-responder: 33 (8–44) ms], TLVAT [−0.68; 81 (73–97) vs. 112 (96–127) ms], scar [−0.27; 0.0 (0.0–1.2) vs. 8.7 (0.0–19.1)%], and SSI [0.41; 10.7 (7.1–16.8) vs. 4.2 (2.9–5.5)], but not QRSd [−0.13; 155 (140–176) vs. 167 (155–177) ms]. TLVAT and SSI were highly accurate in identifying CRT response [area under the curve (AUC) > 0.80], followed by scar (AUC > 0.70). Total left-ventricular activation time (odds ratio = 0.91), scar (0.94), and SSI (1.29) were independent factors associated with effective CRT. Subjects with SSI >7.9% and TLVAT <91 ms all responded to CRT with a median ΔESV ≈ −50%, while low SSI and prolonged TLVAT were more common in non-responders (ΔESV ≈ −5%).Conclusion: Electromechanical measurements are better associated with CRT response than conventional ECG variables. The absence of scar combined with high SSI and low TLVAT ensures effectiveness of CRT.

Aims: The application of conduction system pacing (CSP) in clinical practice is growing, and the need for lead extraction will also increase. The data on outcomes and safety of CSP lead extraction are limited. The aim of this study was to assess procedural outcomes and safety of CSP lead removal. Methods and results: Forty-seven patients from the EXTRACT Registry with the indication for CSP lead removal were enrolled in the study conducted at the Department of Electrocardiology in Katowice, Poland. Extraction technique, outcomes, safety, and complication were evaluated. Forty-three (91.5%) leads were successfully removed, and 41 (87.2%) were removed with traction only. The dwelling time of 28 extracted leads was longer than 1 year, and the oldest extracted lead was implanted for 89 months. Seven (14.9%) leads were removed from the left bundle branch (LBB) area and 36 from the His bundle (HB). Transient complete atrioventricular block occurred during the procedure in two patients. In 27 out of 31 attempts (87.1%), new CSP leads were implanted: nine (33.3%) HB pacing leads and 18 (66.7%) LBB area pacing leads. Conclusion: The CSP lead extraction is safe and feasible with a low complication rate and high rate of CSP lead reimplantation.

Background: The lead breakage (LB) during transvenous lead extraction (TLE) increases procedural complexity, increases the risk of complications, and decreases procedural efficiency. This study aimed to identify protective and risk factors for the breakage of cardiac electronic device leads during extraction. Methods: Data were sourced from the EXTRACT prospective registry for TLE procedures conducted between January 2016 and June 2025. A total of 702 consecutive TLE procedures involving 1375 leads were enrolled. Multivariate logistic regression was used to identify independent protective and risk factors and develop a model to predict the occurrence of LB during TLE. Results: In the analysed group, 56 (7.98%) of 702 TLE procedures were disrupted by the breakage of at least one lead. The model showed a lower lead breakage rate in procedures when an atrial lead was simultaneously extracted, a locking stylet was used, and when the procedure was conducted in older patients or those who had undergone prior cardiac surgery. Higher risk of LB was proven in the following cases: the extraction of leads implanted a long time ago; the extraction of VDD-type leads; the extraction of abandoned leads; extraction during a prolonged procedure. Occurrence of lead breakage may lead to pericardial effusion requiring intervention, acute kidney injury, or leaving remnants of the leads. Conclusions: Lead breakage is an underestimated procedural difficulty that can occur during transvenous lead extraction. In this study, several clinical and procedural variables were independently associated with lead breakage. Abandoned leads, VDD leads, and prolonged procedure time were associated with increased risk. In contrast, older age, use of a locking stylet, atrial lead extraction, prior cardiac surgery, and later year of implantation demonstrated independent protective associations.

Background/Objective: The EXTRACT registry cohort of 504 patients undergoing transvenous lead extraction (TLE) has been previously reported in terms of periprocedural safety and short-term outcomes. Data on long-term mortality and its predictors in this population remain limited. The study aimed to identify risk factors for overall mortality at three years following TLE. Methods: This is a secondary, long-term follow-up analysis of the previously published EXTRACT registry cohort of 504 consecutive patients who underwent TLE between 2016 and 2022. We conducted a univariate analysis to predict mortality risk following TLE, followed by Cox regression with cross-validation to identify independent predictors of mortality over a 3-year follow-up period; Brier score assessed prediction accuracy for mortality; and decision curve analysis evaluated the clinical usefulness of the model. Results: Mortality data were completed for 487 patients at three-year follow-up. Long-term outcomes of TLE showed that patients with CIED infection (p = 0.0091), higher NYHA class (p < 0.0001), arterial hypertension (p = 0.0068), previous stroke (p = 0.0092), upgraded to condition pacing post-TLE (p = 0.0092), and higher CHA₂DS₂-VA score (p = 0.0026) had markedly higher mortality at three-year follow-up. Increased mortality was independently associated with estimated glomerular filtration rate (eGFR) and the CHA₂DS₂-VA score. Risk increased incrementally with each 1 mL/min/1.73 m² decrease in eGFR (hazard ratio, 0.99; 95% CI, 0.98–0.99), and each 1-point increase in CHA₂DS₂-VA conferred a 12% higher mortality rate (hazard ratio, 1.12; 95% CI, 1.02–1.23). Conclusions: In this prospective registry, 3-year mortality after TLE was driven predominantly by baseline clinical risk rather than procedural factors. Renal dysfunction and a higher CHA₂DS₂-VA score independently predicted death, supporting the incorporation of kidney function and global vascular risk into pre-extraction assessment and post-extraction management.

Sleep-disordered breathing (SDB), i.e., central sleep apnea (CSA) and obstructive sleep apnea (OSA), affects the prognosis of patients with heart failure with reduced ejection fraction (HFrEF). The study assessed the relationships between heart chamber size or function and respiratory parameters in patients with HFrEF and various types of SDB. The 84 participants were patients aged 68.3 ± 8.4 years (80% men) with an average left ventricular ejection fraction (LVEF) of 25.5 ± 6.85% who qualified for cardioverter-defibrillator implantation with or without cardiac resynchronization therapy. SDB, defined by an apnea–hypopnea index (AHI) ≥ five events/hour, was diagnosed in 76 patients (90.5%); SDB was severe in 31 (36.9%), moderate in 26 (31.0%), and mild in 19 (22.6%). CSA was the most common type of SDB (64 patients, 76.2%). A direct proportional relationship existed only in the CSA group between LVEF or stroke volume (SV) and AHI (p = 0.02 and p = 0.07), and between LVEF or SV and the percentage of total sleep time spent with hemoglobin oxygen saturation < 90% (p = 0.06 and p = 0.07). In contrast, the OSA group was the only group in which right ventricle size showed a positive relationship with AHI (for basal linear dimension [RVD1] p = 0.06), mean duration of the respiratory event (for RVD1 p = 0.03, for proximal outflow diameter [RVOT proximal] p = 0.009), and maximum duration of respiratory event (for RVD1 p = 0.049, for RVOT proximal p = 0.006). We concluded that in HFrEF patients, SDB severity is related to LV systolic function and SV only in CSA, whereas RV size correlates primarily with apnea/hypopnea episode duration in OSA.