HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

In patients chronically implanted with leadless pacemakers, there were no significant changes in heart structure and function observed, especially concerning the RV and TV.

All procedures were performed under conscious sedation. Briefly, a quadripolar catheter Josephson curve (St. Jude Medical, Minnetonka, MN) was positioned on the His bundle and a deflectable quadripolar catheter (Xtrem catheter; Sorin Group) was placed in the coronary sinus by the femoral route. These 2 catheters were used as landmarks for transseptal puncture to allow placement of a steerable 15 Fr sheath © 2015 American Heart Association, Inc. Original ArticleBackground-Electromyography-guided phrenic nerve (PN) monitoring using a catheter positioned in a hepatic vein can aid in preventing phrenic nerve palsy (PNP) during cryoballoon ablation for atrial fibrillation. We wanted to evaluate the feasibility and efficacy of PN monitoring during procedures using second-generation cryoballoons. Methods and Results-This study included 140 patients (43 women) in whom pulmonary vein isolation was performed using a second-generation cryoballoon. Electromyography-guided PN monitoring was performed by pacing the right PN at 60 per minute and recording diaphragmatic compound motor action potential (CMAP) via a quadripolar catheter positioned in a hepatic vein. If a 30% decrease in CMAP amplitude was observed, cryoapplication was discontinued with forced deflation to avoid a PNP. Monitoring was unfeasible in 8 of 140 patients (5.7%), PNP occurred in 1. Stable CMAP amplitudes were achieved before ablation in 132 of 140 patients (94.3%). In 18 of 132 patients (13.6%), a 30% decrease in CMAP amplitude occurred and cryoablation was discontinued. Each time, recovery of CMAP amplitude took <60 s. In 9 of 18 cases, a second cryoapplication in the same pulmonary vein was safely performed. We observed no PNP or complication related to electromyography-guided PN monitoring. Conclusions-Electromyography-guided PN monitoring using a catheter positioned in a hepatic vein seems feasible and effective to prevent PNP during cryoballoon ablation using second-generation cryoballoon. (Circ Arrhythm Electrophysiol. 2015;8:303-307.

Background: QTc interval monitoring, for the prevention of drug-induced arrhythmias is necessary, especially in the context of coronavirus disease 2019 . For the provision of widespread use, surrogates for 12-lead ECG QTc assessment may be useful. This prospective observational study compared QTc duration assessed by artificial intelligence (AI-QTc) (Cardiologs®, Paris, France) on smartwatch single-lead electrocardiograms (SW-ECGs) with those measured on 12-lead ECGs, in patients with early stage COVID-19 treated with a hydroxychloroquine−azithromycin regimen. Methods: Consecutive patients with COVID-19 who needed hydroxychloroquine−azithromycin therapy, received a smartwatch (Withings Move ECG®, Withings, France). At baseline, day-6 and day-10, a 12-lead ECG was recorded, and a SW-ECG was transmitted thereafter. Throughout the drug regimen, a SW-ECG was transmitted every morning at rest. Agreement between manual QTc measurement on a 12-lead ECG and AI-QTc on the corresponding SW-ECG was assessed by the Bland-Altman method. Results: 85 patients (30 men, mean age 38.3 ± 12.2 years) were included in the study. Fair agreement between manual and AI-QTc values was observed, particularly at day-10, where the delay between the 12-lead ECG and the SW-ECG was the shortest (−2.6 ± 64.7 min): 407 ± 26 ms on the 12-lead ECG vs 407 ± 22 ms on SW-ECG, bias −1 ms, limits of agreement −46 ms to +45 ms; the difference between the two measures was <50 ms in 98.2% of patients. Conclusion:In real-world epidemic conditions, AI-QTc duration measured by SW-ECG is in fair agreement with manual measurements on 12-lead ECGs. Following further validation, AI-assisted SW-ECGs may be suitable for QTc interval monitoring. REGISTRATION: ClinicalTrial.gov NCT04371744.