Background: The in-hospital management of patients with cardiac implantable electronic devices (CIEDs) changed early in the COVID-19 pandemic. Routine in-hospital controls of CIEDs were converted into remote home monitoring (HM). The aim of our study was to investigate the impact of the lockdown period on CIEDs patients and its influence on in-hospital admissions through the analysis of HM data. Methods: We analysed data recorded from 312 patients with HM during the national quarantine related to COVID-19 and then compared data from the same period of 2019. Results: We observed a reduction in the number of HM events in 2020 when compared to 2019. Non-sustained ventricular tachycardia episodes decreased (18.3% vs. 9.9% p = 0.002) as well as atrial fibrillation episodes (29.2% vs. 22.4% p = 0.019). In contrast, heart failure (HF) alarm activation was lower in 2019 than in 2020 (17% vs. 25.3% p = 0.012). Hospital admissions for critical events recorded with CIEDs dropped in 2020, including those for HF. Conclusions: HM, combined with telemedicine use, has ensured the surveillance of CIED patients. In 2020, arrhythmic events and hospital admissions decreased significantly compared to 2019. Moreover, in 2020, patients with HF arrived in hospital in a worse clinical condition compared to previous months.