Twice-daily rivaroxaban after percutaneous left atrial appendage closure for atrial fibrillation.

Background and aim: Rivaroxaban is an emerging oral anticoagulant for postoperative anticoagulation after percutaneous left atrial appendage closure (LAAC). Because a once-daily dosing regimen of rivaroxaban causes fluctuations in the drug plasma concentration, we studied the feasibility and safety of twice-daily rivaroxaban as a postoperative anticoagulation regimen for patients with atrial fibrillation (AF) undergoing LAAC. Methods: This study involved patients with AF who underwent LAAC and took rivaroxaban postoperatively. A total of 326 patients who received a standard total dose (15 or 20 mg) of rivaroxaban based on their creatinine clearance rate were divided into the twice-daily (BID) rivaroxaban group (n = 208) and once-daily (QD) rivaroxaban group (n = 118) according to their anticoagulation strategy. Transesophageal echocardiography was recommended at 3-6 months postoperatively to check for device-related thrombosis (DRT). Clinical outcomes were evaluated during postoperative anticoagulation. Results: The median CHA2DS2-VASc score (4 [3, 5] vs. 4 [3, 5], p = 0.28) and HAS-BLED score (2 [2, 3] vs. 2 [2, 3], p = 0.48) were not significantly different between the groups. During the anticoagulation period (4.1 ± 0.7 vs. 4.1 ± 0.9 months, p = 0.58), 148 (71.2%) patients in the BID group and 75 (63.6%) in the QD group underwent follow-up transesophageal echocardiography. There were no statistically significant differences between the two groups in terms of DRT (1.4% vs. 2.7%, p = 0.60), minor bleeding (8.2% vs. 11.0%, p = 0.39), thromboembolic events (1.0% vs. 0.8%, p = 1.00), major bleeding (0.5% vs. 0.8%, p = 1.00), or death. Conclusion: A short course of twice-daily rivaroxaban following LAAC is a feasible alternative regimen with a low rate of major bleeding events, DRT, and thromboembolic events for patients with AF.

Comparing safety and efficacy: MemoLefort versus watchman for left atrial appendage closure.

BACKGROUND: The MemoLefort is a new plug occluder for left atrial appendage closure (LAAC) in patients with atrial fibrillation (AF). This study compares the safety and efficacy of MemoLefort and the well-established Watchman occluder for LAAC. METHODS: Between January 2021 and September 2022, a cohort of 189 consecutive patients who underwent LAAC with MemoLefort or Watchman at The Second Affiliated Hospital of Wenzhou Medical University were included. Patients with MemoLefort or Watchman devices were compared in terms of the primary safety endpoints encompassing major periprocedural complications and major bleeding events at follow-up, the primary efficacy endpoint of all-cause stroke, systemic embolism and cardiovascular/unexplained death, and the combined hazard endpoint, a composite of all the above-mentioned hazards. RESULTS: Of the MemoLefort group (n = 83) and Watchman group (n = 106), the mean age, CHA2DS2-VASc score, and HAS-BLED score were 67.6 ± 9.2 vs. 69.0 ± 10.6 years, 3.9 ± 1.9 vs. 3.8 ± 1.9, and 1.6 ± 1.0 vs. 1.7 ± 1.2, respectively. After a median follow-up duration of 198 (99-329) vs. 334 (171-497) days, the primary endpoints of efficacy [2/49, 4.1% (MemoLefort) vs. 2/97, 2.1% (Watchman); hazard ratio (HR), 1.50; 95% confidence interval (CI), 0.20-11.08; P = 0.68] and safety (1/49, 2.0% vs. 5/97, 5.2%; HR, 0.26; 95% CI, 0.05-1.31; P = 0.19), as well as the combined hazard endpoint (3/49, 61% vs. 6/97, 6.2%; HR, 0.70; 95% CI, 0.18-2.58; P = 0.59) were similar between groups. CONCLUSIONS: In the short term, LAAC with MemoLefort provided similar efficacy, safety, and net clinical benefit in comparison to Watchman devices.

Percutaneous left atrial appendage closure using the LAmbre device in patients with atrial fibrillation and left atrial appendage thrombus.

Background: Left atrial appendage closure (LAAC) is considered a valid alternative for the prevention of thromboembolic stroke in patients with persistent left atrial appendage thrombus (LAAT) despite adequate anticoagulation. However, the data on LAAC using the LAmbre device for patients with LAAT is limited. This study was performed to explore efficacy and safety as well as to share the experience of the modified LAAC procedure with the LAmbre device. Materials and methods: A total of 7 patients with persistent LAAT despite adequate anticoagulation underwent modified LAAC with the LAmbre device between November 2019 and April 2022. Transesophageal echocardiography was performed 3 months postoperatively to detect device-related thrombosis and peridevice leak. The patients' clinical events were evaluated during the perioperative and follow-up periods. Results: The median age, CHA2DS2-VASc score, and HAS-BLED score of all patients were 71 [53-73], 3 [2-4], and 2 [2-3], respectively. In the procedure, a cerebral protection system was used in two patients. LAAC with the LAmbre device was successfully performed in all patients without perioperative events. During the median follow-up of 383 [325-865] days, postoperative transesophageal echocardiography was performed in six (85.7%) patients. Device-related thrombosis was detected in one (16.7%) patient, and no significant peridevice leak was observed. No thromboembolic event or bleeding event occurred in any patients. Conclusion: LAAC with the LAmbre device is effective and safe when performed by experienced operators in highly selected patients with LAAT after adequate anticoagulation.

Combined atrial fibrillation ablation and left atrial appendage closure: Watchman vs. LAmbre devices.

Background: Left atrial appendage closure (LAAC) combined with radiofrequency catheter ablation is an emerging one-stop hybrid procedure for non-valvular atrial fibrillation (AF). This study was performed to compare the efficacy and safety of the Watchman device vs. the LAmbre device for this combined procedure. Methods: Two hundred and thirty two patients with AF who underwent the combined procedure were enrolled and divided into two subgroups depending on the device choice: the Watchman-combined group (n = 118) and the LAmbre-combined group (n = 114). The periprocedural and follow-up adverse events in both groups were documented. Results: The mean CHA2DS2-VASc score and HAS-BLED score in the Watchman-combined group and LAmbre-combined group were 3.7 ± 1.5 vs. 3.8 ± 1.5 and 2.5 ± 1.1 vs. 2.3 ± 1.1, respectively (all P > 0.05). Successful LAAC was achieved in all patients. The rate of major periprocedural complications and AF recurrence at 6 months post-procedure were similar between the Watchman-combined group and LAmbre-combined group (0.8 vs. 0.9%, P = 1.00; 22.0 vs. 15.8%, P = 0.23). During 2.6 ±0 .7 vs.1.6 ± 1.6 years follow-up, the rate of major clinical adverse events, including stroke and major bleeding, were comparable between the Watchman-combined group and the LAmbre-combined group (2.6 vs. 1.1% per 100 patient-years, P = 0.33). The intraprocedural peri-device leakage (PDL) rate was similar between the Watchman-combined group and the LAmbre-combined group (5.1 vs. 6.1%, P = 0.73), but the PDL rate was significantly higher at 3-6 months transesophageal echocardiography (TEE) follow-up than the intraprocedural PDL rate in both groups (21.6 vs. 5.1%; 36.6 vs. 6.1%, respectively), with a more obvious increase in minimal PDL rate in the LAmbre-combined group than the Watchman-combined group (36.6 vs. 21.6%, P < 0.05). Conclusion: The Watchman and LAmbre devices were comparable in efficacy and safety for the combined procedure. The minimal PDL rate at short-term TEE follow-up was higher in the LAmbre-combined group than the Watchman-combined group.

First Report of Twig Anthracnose of Acacia melanoxylon Caused by Colletotrichum siamense in China.

Acacia melanoxylon R. Br. native to Australia, is a high-quality timber tree with wide genetic and phenotypic diversity. In recent years, A. melanoxylon has been extensively cultivated in some provinces in southern China. In December 2019, anthracnose-like symptoms were observed on twigs of A. melanoxylon in China. In certain valleys in south China, the disease incidence on plants and shoots was 60-75% and 80-90%, respectively. The wither rate of disease branches was 30-40% in dry seasons from September to November. The appearance of symptoms occurred in a humid and warm valley. Symptoms were initially observed on the young branches as brown spindle shaped sunken spots. At later stages, the disease spots girdled the whole branch, which became wilted and its leaves turned reddish-brown. For pathogen isolation, diseased branches were sampled and 55 pieces (5× 5 mm) of these branches section were surface-sterilized in 75% ethanol for 30 seconds, followed by 0.5% NaClO for 5 min and then were rinsed three times in distilled water. After drying with sterilized filter paper, the surface-sterilized sections were transferred to potato dextrose agar medium (PDA) and incubated at 25 °C for 7 days in the dark. Three isolates were obtained as representatives for morphological characterization and were labeled as 1A912, 1B912, and 1C912. These specimens were deposited in the Guangdong Province Key Laboratory of Microbial Signals and Disease Control at the South China Agricultural University (China). Purified isolates were initially white, cottony and with dense aerial mycelium on PDA at 25 ℃, ten days later their colonies turned grayish white with orange conidial masses. Conidia were one-celled, hyaline, straight, cylindrical, with round obtuse ends, and measured 11.0 to16.3× 4.0 to 6.0 µm (n= 100), appressoria were 5.86 to 9.07 × 3.55 to 6.96 µm (n= 100). Morphological characteristics of selected isolates matched the Colletotrichum gloeosporioides species complex (Weir et al. 2012). For further identification, the internal transcribed spacer (ITS) region, and partial sequences of the actin (ACT), beta-tubulin (TUB2), and glycerol dehyde-3-phosphate dehydrogenase (GAPDH) genes were amplified by PCR, and sequenced, using primer pairs ITS1/ ITS4 (White et al. 1990), Bt2a/ Bt2b (Donaldson and Glass 1995), ACT512F/ ACT783R, GDF1/ GDR1(Weir et al. 2012). The sequences were deposited in GenBank (ITS: MW228101-MW228103; TUB2: MW250346, MW320707, MW320708; ACT: MW250347, MW320703, MW320704; GAPDH: MW250348, MW320705, MW320706). The multilocus phylogenetic analysis distinguished the isolates 1A912, 1B912, and 1C912 as C. siamense. Pathogenicity of those three isolates of C. siamense was tested on healthy twigs of the one clone of A. melanoxylon. 27 young twigs of nine 1-year-old plants were inoculated with the mycelium of the 7 days-old isolates 1A912, 1B912, and 1C912(Each isolate infected three plants and each infected three young twigs) through an artificial wound. The same nine plants were inoculated with PDA medium alone (each infected three young twigs) as a negative control. Five days after inoculation, brown spindle spots similar to the field disease symptoms were observed on the twigs. No symptoms were observed on the control plants. The experiment was repeated twice. The fungus was successfully reisolated from the symptomatic plants, and had identical morphological and molecular characteristics to the initial isolates, fulfilling Koch´s postulates. To our knowledge, this is the first report of anthracnose caused by C. siamense on A. melanoxylon in China. Twig anthracnose can reduce the growth of A. melanoxylon. Further research on management options for this disease is required.