Luigi Di Biase

Aims Since their introduction in 1958, traditional cardiac pacemakers have undergone considerable upgrades over the years, but they continue to have a complication rate of ∼3.8%–12.4%. There are no randomized controlled trials comparing outcomes of leadless pacemakers (LPM) with single-chamber transvenous pacemakers (TV-VVI). The aim is to assess the differences in the procedural complications and in-hospital outcomes between LPM and TV-VVI implants. Methods and results We queried the national inpatient database from 2016 to 2019 to include adult patients undergoing LPM and TV-VVI. Admissions for leadless and single-lead transvenous pacemakers were identified by their appropriate ICD-10 codes. Complications were identified using ICD-10 codes that mostly represent initial encounter. The difference in outcomes was assessed using multivariable logistic regression and 1:1 propensity score matching between the two cohorts. Thirty-five thousand four hundred thirty expanded samples of admissions were retrieved of which 27 650 (78%) underwent TV-VVI with a mean age 81.3 ± 9.4 years and 7780 (22%) underwent LPM with a mean age of 77.1 ± 12.1 years. The LPM group had a higher likelihood of in-hospital mortality [adjusted odds ratio (aOR): 1.63, 95% CI (1.29–2.05), P < 0.001], vascular complications [aOR: 7.54, 95% CI (3.21–17.68), P < 0.001], venous thromboembolism [aOR: 3.67, 95% CI (2.68–5.02), P < 0.001], cardiac complications [aOR: 1.79, 95% CI (1.59–2.03), P < 0.001], device thrombus formation [aOR: 5.03, 95% CI (2.55–9.92), P < 0.001], and need for a blood transfusion [aOR: 1.54, 95% CI (1.14–2.07), P < 0.005]. The TV-VVI group had higher likelihood of in-hospital pulmonary complications [aOR:0.68, 95% CI (0.54–0.87), P < 0.002] and had a need for device revisions [aOR:0.42, 95% CI (0.23–0.76), P < 0.004]. Conclusion There is a higher likelihood of all-cause in-hospital mortality and complications following LPM implantation in comparison to TV-VVI. This could be related to higher co-morbidities in the LPM group. Clinical trials aimed to accurately compare these two groups should be undertaken.

Aims Intracardiac echocardiography (ICE) is a useful but operator-dependent tool for left atrial (LA) anatomical rendering during atrial fibrillation (AF) ablation. The CARTOSOUND FAM Module, a new deep learning (DL) imaging algorithm, has the potential to overcome this limitation. This study aims to evaluate feasibility of the algorithm compared to cardiac computed tomography (CT) in patients undergoing AF ablation. Methods and results In 28 patients undergoing AF ablation, baseline patient information was recorded, and three-dimensional (3D) shells of LA body and anatomical structures [LA appendage/left superior pulmonary vein/left inferior pulmonary vein/right superior pulmonary vein/right inferior pulmonary vein (RIPV)] were reconstructed using the DL algorithm. The selected ultrasound frames were gated to end-expiration and max LA volume. Ostial diameters of these structures and carina-to-carina distance between left and right pulmonary veins were measured and compared with CT measurements. Anatomical accuracy of the DL algorithm was evaluated by three independent electrophysiologists using a three-anchor scale for LA anatomical structures and a five-anchor scale for LA body. Ablation-related characteristics were summarized. The algorithm generated 3D reconstruction of LA anatomies, and two-dimensional contours overlaid on ultrasound input frames. Average calculation time for LA reconstruction was 65 s. Mean ostial diameters and carina-to-carina distance were all comparable to CT without statistical significance. Ostial diameters and carina-to-carina distance also showed moderate to high correlation (r = 0.52–0.75) except for RIPV (r = 0.20). Qualitative ratings showed good agreement without between-rater differences. Average procedure time was 143.7 ± 43.7 min, with average radiofrequency time 31.6 ± 10.2 min. All patients achieved ablation success, and no immediate complications were observed. Conclusion DL algorithm integration with ICE demonstrated considerable accuracy compared to CT and qualitative physician assessment. The feasibility of ICE with this algorithm can potentially further streamline AF ablation workflow.