Implantable loop recorders (ILRs) are increasingly being used for long-term cardiac monitoring in different clinical settings. The aim of this study was to investigate the real-world performance of ILRs-including the time to diagnosis- in unselected patients with different ILR indications. In this multicenter, observational study, 871 patients with an indication of pre-syncope/syncope (61.9%), unexplained palpitations (10.4%), and atrial fibrillation (AF) detection with a history of cryptogenic stroke (CS) (27.7%) underwent ILR implantation. The median follow-up was 28.8 ± 12.9 months. In the presyncope/syncope group, 167 (31%) received a diagnosis established by the device. Kaplan-Meier estimates indicated that 16.9% of patients had a diagnosis at 6 months, and the proportion increased to 22.5% at 1 year. Of 91 patients with palpitations, 20 (22%) received a diagnosis based on the device. The diagnosis established at 12.2% of patients at 6 months, and the proportion increased to 13.3% at 1 year. Among 241 patients with CS, 47 (19.5%) were diagnosed with AF. The diagnostic yield of the device was 10.4% at 6 months and 12.4% at 1 year. In all cases, oral anticoagulation was initiated. Overall, ILR diagnosis altered the therapeutic strategy in 26.1% in presyncope/syncope group, 2.2% in palpitations group, and 3.7% in CS group in addition to oral anticoagulation initiation. In this real-world patient population, ILR determines diagnosis and initiates a new therapeutic management in nearly one fourth of patients. ILR implantation is valuable in the evaluation of patients with unexplained presyncope/syncope, CS and palpitations.

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).

High-power short duration(HPSD) and very high-power short duration(vHPSD-90W/4s) radiofrequency(RF) technology has reduced the procedure time of pulmonary vein isolation(PVI) using RF without compromising the efficacy of the technique. The current study compares the novel technology of HPSD/vHPSD with cryoablation(CRYO) in terms of efficacy, safety and procedure time in a cohort of symptomatic patients with paroxysmal atrial fibrillation(pAF). This is a prospective non-randomized trial. Patients with pAF received either CRYO or HPSD/vHPSD RF PVI. The primary endpoint of the study was arrhythmia recurrence in 12 months follow-up period. Secondary endpoints included procedure time, fluoroscopy time and safety. 104 patients were included (45 in HPSD/vHPSD and 59 in CRYO), with comparable characteristics between groups. The follow-up was 12.4 +/- 0.5 months. There was no significant difference regarding arrhythmia recurrences during the early post-procedural period of first 3 months (8.9% recurrences in HPSD/vHPSD versus 5.1% in CRYO-p 0.463) and in the mid-term follow up of 12 months (17.8% recurrences in HPSD/vHPSD versus 10.2% in CRYO-p 0.385). Safety was excellent for both procedures. CRYO was a procedure of significantly shorter duration (64.64±8.94 min versus 75.29±18.30min, p 0.0001) at the expense of longer fluoroscopy time (HPSD/vHPSD 5.34±1.83 versus 7.89±3.70min CRYO, p 0.001). HPSD/vHPSD and CRYO in pAF were comparable regarding the arrhythmia recurrence rates in a 12 months follow-up with excellent safety. The hybrid approach of HPSD/vHPSD has accelerated RF-PVI, compared to conventional RF, but CRYO remains a procedure of significantly shorter duration at the expense of longer fluoroscopy time.

Managing patients with both Klinefelter syndrome (KS) and Brugada syndrome (BrS) is challenging because of the rarity of this unique interaction. A man diagnosed with KS during fertility treatment experienced chronic muscle pain, severe depression, and cognitive difficulties, managed with testosterone therapy and antidepressants. Increased testosterone doses led to recurrent episodes of loss of consciousness, initially considered epileptic. Hormonal assessments, cardiac imaging, Holter monitoring, electrophysiological studies, and genetic testing led to BrS diagnosis. A positive ventricular tachycardia stimulation study led to the implantation of an implantable cardioverter-defibrillator. Following implantable cardioverter-defibrillator insertion, discontinuing testosterone, and changing medication, the patient has remained stable. The coexistence of KS and BrS is extremely rare. Understanding hormonal and genetic interactions in managing such complex cases is crucial.

Bradycardia-induced monomorphic ventricular tachycardia (VT) is an underrecognized proarrhythmic mechanism in dilated cardiomyopathy (DCM). This case series describes patients with advanced heart failure and recurrent VT/ventricular fibrillation in whom upgrading from single- to dual-chamber implantable cardioverter-defibrillators (ICDs) provided arrhythmia suppression. Three patients with DCM, recurrent sustained VT/ventricular fibrillation, and hemodynamic instability due to bradycardia, pacing-related cycle-length variability, and loss of atrioventricular (AV) synchrony were retrospectively analyzed before and after ICD upgrade. All patients demonstrated bradycardia-triggered monomorphic VT and clinical deterioration during ventricular pacing without AV synchrony. Upgrading to a dual-chamber system with atrial pacing corrected bradycardia, normalized cycle length, restored AV synchrony, and reduced arrhythmia burden. Two patients underwent heart transplantation under improved conditions, and 1 patient remained arrhythmia-free during long-term follow-up. Dual-chamber ICD upgrade offers an effective strategy for preventing bradycardia-induced monomorphic VT in advanced DCM by stabilizing heart rate and eliminating proarrhythmic pacing sequences.