Prognostic Electrocardiographic Signs in Arrhythmogenic Cardiomyopathy.

Arrhythmogenic cardiomyopathy (ACM) is a rare cardiac disease, characterized by the progressive replacement of myocardial tissue with fibrous and fatty deposits. It can involve both the right and left ventricles. It is associated with the development of life-threatening arrhythmias and culminates in sudden cardiac death. Electrocardiography (ECG) has emerged as a pivotal tool, offering diagnostic insights and prognostic information. The specific ECG abnormalities observed in ACM not only contribute to early detection but also hold the key to the prediction of the likelihood of severe complications. The recognition of these nuanced ECG manifestations has become imperative for clinicians as it guides them in the formulation of tailored therapeutic strategies that address both the present symptoms and the potential future risks.

Comparative Study of Lesions Obtained through Radiofrequency between the Irrigated Ablation Catheter with a Flexible Tip and the Non-Irrigated Catheter in Ex Vivo Porcine Hearts.

BACKGROUND: At the same conditions of delivered power and contact force, open-irrigated radiofrequency ablation catheters are believed to create deeper lesions, while non-irrigated ones produce shallower lesions. This ex vivo study aims to directly compare the lesion dimensions and characteristics of an irrigated ablation catheter with a flexible tip and a non-irrigated solid-tip catheter. METHODS: Radiofrequency lesions were induced on porcine myocardial slabs using both open-tip irrigated and non-irrigated standard 4 mm catheters at three power settings (20 W, 30 W, and 40 W), maintaining a fixed contact force of 10 gr. A lesion assessment was conducted including the lesion depth, depth at the maximum diameter, and lesion surface diameters, with the subsequent calculation of the lesion volume and area being undertaken. RESULTS: Irrigated catheters produced lesions with significantly higher superficial widths at all power levels (3.8 vs. 4.4 mm at 20 W; 3.9 mm vs. 4.4 mm at 30 W; 3.8 mm vs. 4.5 mm at 40 W; p = 0.001, p = 0.019, p = 0.003, respectively). Non-irrigated catheters resulted in significantly higher superficial areas at all power levels (23 mm2 vs. 18 mm2 at 20 W; 25 mm2 vs. 19 mm2 at 30 W; 26 mm2 vs. 19 mm2 at 40 W; p = 0.001, p = 0.005, p = 0.001, respectively). Irrigated catheters showed significantly higher values of lesion maximum depth at 40 W (4.6 mm vs. 5.5 mm; p = 0.007), while non-irrigated catheters had a significantly higher calculated volume at 20 W (202 µL vs. 134 µL; p = 0.002). CONCLUSIONS: Radiofrequency ablation using an irrigated catheter with a flexible tip has the potential to generate smaller superficial lesion areas compared with those obtained using a non-irrigated catheter.

Ultrasound-Guided Venous Axillary Access Versus Standard Fluoroscopic Technique for Cardiac Lead Implantation: ZEROFLUOROAXI Randomized Trial.

BACKGROUND: Axillary vein puncture (AVP) and cephalic vein surgical cutdown are recommended in international guidelines because of their low risk of pneumothorax and chronic lead complications. Directly visualizing and puncturing the axillary vein under ultrasound guidance reduces radiation exposure, provides direct needle visualization, and lowers periprocedural complications. Our hypothesis is that ultrasound-guided axillary access is safer and more feasible than the standard fluoroscopic technique. OBJECTIVES: The purpose of this study was to assess the efficacy and safety of ultrasound-guided axillary venous access during cardiac lead implantation for pacemakers (PMs) and implantable cardioverter-defibrillator (ICD) implantations. METHODS: Patients were randomized in a 1:1 fashion to either axillary venous access under fluoroscopic guidance or ultrasound-guided axillary venous access. The composite outcome, including pneumothorax, hemothorax, inadvertent arterial puncture, pocket hematoma, pocket infection, lead dislodgement, and death, was evaluated 30 days after implantation. RESULTS: We randomized 270 patients into 2 groups: the standard group for fluoroguided AVP (n = 134) and the experimental group for ultrasound-guided AVP (n = 136). No disparities in baseline characteristics were observed between the groups. The median age of the patients was 81 years, with women comprising 41% of the population. The majority of patients received single- and dual-chamber PMs (87% vs 88%; P = 1.00), and slightly over 10% in both groups received ICDs (13% vs 12%; P = 0.85). In total, we placed 357 leads in PMs and 48 leads in ICDs. Among these, 295 leads were inserted via axillary vein access and 110 via cephalic vein access. Notably, the subclavian vein was never used as a vascular access. The composite outcome was lower in the ultrasound group according to intention-to-treat analysis (OR: 0.55; 95% CI: 0.31-0.99; P = 0.034). The main difference within the composite outcome was the lower incidence of inadvertent axillary arterial puncture in the experimental group (17% vs 6%; P = 0.004). The ultrasound group also exhibited lower total procedural x-ray exposure (10,344 µGy × cm2 vs 7,119 µGy × cm2; P = 0.002) while achieving the same rate of success at the first attempt (61% vs 69%; P = 0.375). CONCLUSIONS: Ultrasound-guided AVP is safer than the fluoroscopy-guided approach because it achieves the same rate of acute success while maintaining low total procedural radiation exposure. Ultrasound AVP should be considered the optimal venous access method for cardiac lead implantation. (Ultrasound Guided Axillary Access vs Standard Fluoroscopic Technique for Cardiac Lead Implantation [ZEROFLUOROAXI]; NCT05101720).

A Comparative Assessment of Myocardial Work Performance during Spontaneous Rhythm, His Bundle Pacing, and Left Bundle Branch Area Pacing: Insights from the EMPATHY Study.

BACKGROUND: Physiological pacing has gained significant interest due to its potential to achieve optimal hemodynamic response. This study aimed to assess left ventricular performance in terms of electrical parameters, specifically QRS duration and mechanical performance, evaluated as myocardial work. We compared His Bundle Pacing (HBP) and Left Bundle Branch Area Pacing (LBBAP) to evaluate their effects. METHODS: Twenty-four patients with class I or IIa indications for pacing were enrolled in this study, with twelve patients undergoing HBP implantation and another twelve undergoing LBBAP implantation. A comprehensive analysis of myocardial work was conducted. RESULTS: Our findings indicate that there were no major differences in terms of spontaneous and HBP activation in myocardial work, except for global wasted work (217 mmHg% vs. 283 mmHg%; p 0.016) and global work efficiency (87 mmHg% vs. 82 mmHg%; p 0.049). No significant differences were observed in myocardial work between spontaneous activation and LBBAP. Similarly, no significant differences in myocardial work were found between HBP and LBBAP. CONCLUSIONS: Both pacing modalities provide physiological ventricular activation without significant differences when compared to each other. Moreover, there were no significant differences in QRS duration between HBP and LBBAP. However, LBBAP demonstrated advantages in terms of feasibility, as it achieved better lead electrical parameters compared to HBP (threshold@0.4 ms 0.6 V vs. 1 V; p = 0.045-sensing 9.4 mV vs. 2.4 mV; p < 0.001). Additionally, LBBAP required less fluoroscopy time (6 min vs. 13 min; p = 0.010) and procedural time (81 min vs. 125 min; p = 0.004) compared to HBP.