ABSTRACT Objective: To investigate the risk factors for predicting atrial high-rate episodes (AHREs) detected by cardiac implantable electronic devices (CIEDs). Methods: A total of 140 patients with CIED in our hospital from June 2013 to June 2018 were included and were followed up to observe whether they had AHREs. AHRE are defined as atrial rate ≥ 175 times/minute, lasting > 5 minutes, and reviewed by an experienced electrophysiologist with unclear clinical diagnosis. The patients fasted for 12 hours after implantation, and blood samples were collected for biochemical, lipid, and whole blood count detection. Follow-up was regular after discharge to record follow-up data of each patient and conduct statistical analysis. Results: One hundred and forty patients were implanted with dual-chamber pacemakers, their median age was 70 years old, 44.29% were male, 27 patients had AHRE within one year, and AHRE incidence rate was 19.29%. The microcytic to hypochromic (M/H) ratio was calculated for all AHRE patients and compared with the patients without AHRE; the M/H value of AHRE patients was significantly higher. Throughout the entire follow-up period, a total of 44 patients developed AHRE; when adjusted by multivariate analysis, only M/H ratio ≥ 4.5 vs. < 4.5 had statistical significance, and the adjusted hazard ratio value was 4.313 (1.675-11.105). Conclusion: As an indicator, M/H ratio may play an important role in the occurrence and development of atrial fibrillation and can be used as a predictor of AHRE in patients with CIED.

Abstract This study aimed to estimate the allelopathic intensity of four Asteraceae invasive plant species (IPS), including Conyza canadensis (L.) Cronq., Erigeron annuus (L.) Pers., Bidens pilosa (L.), and Aster subulatus Michx., by testing the effect of leaf extracts on the seed germination and seedling growth (SGe and SGr) of lettuce (Lactuca sativa L.) in combination with two particle sizes of silver nanoparticles. These four IPS decreased the germination of lettuce seeds but increased the growth of lettuce seedlings. The allelopathic intensity of the four IPS decreased in the following order: B. pilosa > C. canadensis > E. annuus > A. subulatus. Silver nanoparticles decreased the SGe and SGr of lettuce. The 20 nm silver nanoparticles affected the competition intensity for water and the absorption of inorganic salts by lettuce more intensively than the 80 nm nanoparticles. Silver nanoparticles intensify the allelopathic intensity of the four invasive plant species on the SGe and SGr of lettuce. The allelopathic intensity of B. pilosa was higher than that of the other three IPS when they were polluted with silver nanoparticles. Thus, silver nanoparticles could facilitate the invasion process of the four IPS, particularly B. pilosa, via an increase in the intensity of allelopathy.