Vasileios Cheilas

Background: Reverse remodeling after cardiac resynchronization therapy with defibrillator backup (CRT-D) is heterogeneous and may reflect both pre-implant substrate and post-implant electrical response, with implications for subsequent outcomes. Objectives: This study evaluated a graded echocardiographic response framework after CRT-D as an integrative phenotype linking pre-implant substrate, peri-implant electrical features, and post-landmark clinical outcomes. Methods: The analytic cohort included 334 CRT-D recipients with complete four-group classification based on relative left ventricular end-systolic volume reduction at the first eligible post-implant echocardiogram. Baseline correlates of the 4-class response phenotype were assessed using ordinal logistic regression, supported by permutation-importance analysis. A stacked peri-implant model added ΔQRS, RV1SI pattern on ECG, left ventricular lead position, and lead depth. Time-to-event analyses used a landmark design anchored at the first post-CRT echocardiogram. Results: In the pre-implantation ordinal model, female sex (p = 0.005), higher baseline left ventricular ejection fraction (p = 0.032), left bundle branch block (p = 0.038), and dilated cardiomyopathy (p = 0.048) were associated with a more favorable response class. In the stacked peri-implant model, ΔQRS was the strongest correlate of higher response class (OR: 1.41; 95% CI: 1.15–1.73; p = 0.0008). Mortality differed across response classes (log-rank p < 0.001); compared with super-responders, negative responders had higher adjusted mortality (HR: 4.41; 95% CI: 1.82–10.70). At 60 months, heart failure hospitalization ranged from 23.3% to 2.9% and first appropriate ICD shock from 29.3% to 9.0% from negative responders to super-responders. Conclusions: After CRT-D, reverse-remodeling phenotype identified clinically distinct post-landmark risk profiles. Less favorable remodeling was associated with worse mortality, heart failure hospitalization, and appropriate ICD shock.

Background: Premature ventricular contractions (PVCs) are common arrhythmias associated with symptoms such as fatigue and, in severe cases, PVC-induced cardiomyopathy. Catheter ablation (CA) is a primary treatment for symptomatic PVCs, particularly when pharmacological therapies fail or are undesired. While improvements in: quality-of-life following ablation are documented, its impact on functional capacity remains underexplored. Objectives: This study evaluated the impact of CA on functional capacity and cardiac stress markers in patients with symptomatic PVCs using cardiopulmonary exercise testing (CPET) and NT-proBNP levels. Methods: A total of 30 patients underwent successful PVC ablation and completed baseline and follow-up CPET evaluations under the Bruce protocol. PVC burden, left ventricular ejection fraction (LVEF), NT-proBNP levels, and CPET parameters, including VO₂ max, METS, ventilatory efficiency, and anaerobic threshold (AT), were analyzed pre- and post-ablation. Results: PVC burden significantly decreased post-ablation (23,509.3 ± 10,700.47 to 1759 ± 1659.15, p < 0.001). CPET revealed improved functional capacity, with VO₂ max increasing from 24.97 ± 4.16 mL/kg/min to 26.02 ± 4.34 mL/kg/min (p = 0.0096) and METS from 7.16 ± 1.17 to 7.48 ± 1.24 (p = 0.0103). NT-proBNP significantly decreased (240.93 ± 156.54 pg/mL to 138.47 ± 152.91 pg/mL, p = 0.0065). LVEF and ventilatory efficiency metrics (VE/VO₂ and VE/VCO₂) remained stable. Conclusions: Catheter ablation improves functional capacity, reduces cardiac stress, and minimizes medication dependency in patients with symptomatic PVCs. These findings support the utility of ablation in enhancing aerobic capacity and overall exercise performance.

Transcatheter Aortic Valve Implantation (TAVI) has revolutionized the treatment of severe aortic stenosis. Although its clinical efficacy is well established, the development of new-onset left bundle branch block (LBBB) following TAVI remains a frequent and concerning complication. This study aims to develop pre-implantation predictive models for new-onset LBBB after TAVI using both conventional machine learning (ML) algorithms and Large Language Models (LLMs). Of the 1113 patients who underwent TAVI over a 15-year period, 469 were included after excluding those with preexisting LBBB, pacing rhythm, or missing relevant data. Pre-procedural clinical parameters - such as valve type, valve size, patient demographics, and comorbidities - were analyzed. The dataset was split into training and testing sets. Several ML algorithms were employed, and performance was evaluated using accuracy, precision, and F1 score. Additionally, LLMs (GPT-3.5 and GPT-4) were assessed using Few-Shot and Chain of Thought (CoT) prompting. New-onset persistent LBBB occurred in 15.29% of patients. Among ML models, XGBoost performed best. GPT-4 with CoT prompting demonstrated superior predictive performance compared to both conventional ML and GPT-3.5. The current study establishes a predictive model leveraging pre-implantation parameters to anticipate the occurrence of new-onset left bundle branch block (LBBB) post-Transcatheter Aortic Valve Implantation (TAVI).

A 73-year-old post-transcather aortic valve implantantion and pacemaker-implanted woman presented with localized redness and pain in the pacemaker pocket region (Figure 1A). Due to initial concerns of an isolated pocket infection, empirical vancomycin administration was initiated after obtaining blood cultures.¹ Despite the general recommendation of a 2–3-day washout period in stable patients to enhance the precision of microbiological diagnosis, we opted for an earlier initiation in consideration of the patient’s frailty and the presence of a prosthetic valve. This decision was tailored to the specific circumstances of the patient to mitigate the risk of further complications. A transthoracic echocardiogram was conducted to identify lead vegetations and assess valvular involvement. Additionally, a transoesophageal echocardiogram was initially scheduled, but the characteristic progression of the skin lesion prompted a reconsideration of this decision since during the next 2 days, a pale multiforme erythematous lesion with vesicles (Figure 1B and C) unfolded, unmasking the herpes zoster antagonist.² In this point, is worth mentioning, that the patient did not have any history of herpes zoster before. Intravenous acyclovir precipitated rapid improvement within a week (Figure 1D and E), while lingering pain and sensitivity persisted for over a month despite complete erythema healing in two weeks (Figure 1F).³ This case highlights the need for identification of distinctive features of rashes suggestive of a pocket infection, consideration for tailored antibiotic initiation, the contemplation of withholding antibiotics in stable patients with concurrent presumed pacemaker pocket infection and confirmed zoster inflammation, and strict adherence to established guidelines for herpes zoster vaccination to prevent similar clinical complexities.