A case of endocardial dissection caused by Micra implantation.

BACKGROUND: Leadless pacemakers are a recent technological advancement. It has many advantages, but there are still a few serious complications. CASE PRESENTATION: This article reports the case of a patient with an endocardial tear and dissection caused by contact with the tip of the Micra cup during surgery and summarises the relevant data. CONCLUSIONS: This case report details the occurrence and management of the incident and provides some guidance for future clinical management.

[Analysis of factors related to systemic embolism in patients≥75 years old with non-valvular atrial fibrillation].

Objective: To explore the related risk factors for systemic embolism (SE) in patients aged≥75 years with non-valvular atrial fibrillation (NVAF). Methods: A case-control study. NVAF patients aged≥75 years who were hospitalized at the First Affiliated Hospital of Xinjiang Medical University from October 2018 to October 2020 were divided into no SE (n=1 127) and SE (n=433) groups according to the occurrence of SE after NVAF. Multivariate logistic regression was used to analyze SE-related factors in patients with NVAF without anticoagulation treatment. Results: In the multivariate model, the following factors were associated with an increased risk of SE in patients with NVAF: history of AF≥5 years [odds ratio (OR)=2.75, 95% confidence interval (CI) 1.98-3.82, P<0.01], lipoprotein(a)>300 g/L (OR=2.07, 95%CI 1.50-2.84, P<0.01), apolipoprotein (Apo)B>1.2 g/L (OR=1.91, 95%CI 1.25-2.93, P=0.003), left ventricular ejection fraction (LVEF) of 30%-49% (OR=2.45, 95%CI 1.63-3.69, P<0.01), left atrial diameter>40 mm (OR=1.54, 95%CI 1.16-2.07, P=0.003), and CHA2DS2-VASc score≥3 (OR=15.14, 95%CI 2.05-112.13, P=0.01). ApoAI>1.6 g/L was negatively correlated with the occurrence of SE (OR=0.28, 95%CI 0.15-0.51, P<0.01). Conclusions: History of AF≥5 years, lipoprotein(a)>300 g/L, elevated ApoB, left atrial diameter>40 mm, LVEF of 30%-49%, and CHA2DS2-VASC score≥3 are independent risk factors for SE whereas ApoAI>1.6 g/L is a protective factor against SE in patients with NVAF.

Evaluation of safety and feasibility of leadless pacemaker implantation following the removal of an infected pacemaker.

BACKGROUND: Leadless pacemakers provide safe and effective pacing options for patients with device-related infections. This study was aimed at observing and evaluating the safety and feasibility of extracting an infected pacemaker device followed by the implantation of a leadless pacemaker in the same location for patients without systemic infection. METHODS: Between December 2019 and September 2020, following a well-planned re-implantation strategy, pacemaker electrodes were removed from patients with device infection and leadless pacemakers were immediately implanted at our center. The patients were then followed up for up to 10 months to assess the safety and practicality of the procedure. RESULTS: Pacemaker electrode removal and immediate leadless pacemaker implantation were successfully achieved in eight patients with pocket infection. After a minimum follow-up period of 1 month and a maximum follow-up of 10 months, the pacing parameters for the patients remained stable and there was no infection at the original capsular bag or in the leadless pacemaker. CONCLUSION: Direct implantation of a leadless pacemaker is safe and feasible for patients with local infection of the pacing system after removal of the electrode as an alternative to a bridge period with a temporary pacemaker. This strategy may be a better option for pacing-dependent patients.

Right ventriculography improves the accuracy of leadless pacemaker implantation in right ventricular mid-septum.

BACKGROUND: Implanting leadless pacemakers in the right ventricular (RV) apex is prone to causing pericardial tamponade and myocardial perforation. OBJECTIVE: To investigate the feasibility and safety of right ventriculography-guided implantation of Micra™ leadless pacemaker (Micra™, Medtronic, Minneapolis, MN, USA) in the RV mid-septum. METHODS: One hundred eight consecutive patients who underwent Micra™ implantation intended in the mid-septum were enrolled and randomized (3:1) into the radiography group (n = 81) with assistance of right ventriculography to illustrate the RV septum and the non-radiography group (n = 27). All subjects underwent a postoperative computed tomography (CT) scan to determine the Micra™ location. The Micra™ location assessed by CT image was compared between the two groups to confirm the accuracy of the intended pacing site. The duration of the procedure, X-ray radiation dose, and time were also compared between the two groups. RESULTS: Reconstructed CT 3-D cardiac images found the Micra™ location in the intended mid-septum in 13 patients (48.1%, 13/27) in the non-radiography group and 76 patients (93.8%, 76/81) in the radiography group (P < 0.0001 between two groups). There was no significant difference in procedure interval between the two groups while the X-ray radiation dose (564.86 ± 112.44 vs. 825.85 ± 156.12 mGy, P < 0.0001), X-ray exposure time (7.79 ± 1.43 vs. 12.03 ± 2.86 min, P < 0.0001), and the number of fluoroscopy re-positioning (2.79 ± 1.03 vs. 6.41 ± 1.82, P < 0.0001) were significantly less in the radiography group than in the non-radiography group. No implantation-related complications were observed in both groups. CONCLUSION: Right ventriculography increases the accuracy of Micra™ implantation in the mid-septum and reduces X-ray exposure. TRIAL REGISTRATION: The trial registration number (ChiCTR2100051374) and date (09/22/2021).

Feasibility, safety and effectiveness of mapping system assisted conduction system pacing: a single-center prospective study.

To assess pacing and electrophysiological parameters, as well as mid-term outcomes, among patients undergoing His bundle pacing (HBP) guided by KODEX-EPD (a novel mapping system). Consecutive patients undergoing conduction system pacing (CSP) for bradycardia indications were evaluated. Procedural and fluoroscopic times and pacing characteristics were compared between conventional fluoroscopy (the standard group, N = 20 cases) and KODEX-EPD mapping system guided group (the KODEX group, N = 20cases) at CSP implantation and all patients were followed at 6-month. HBP was achieved in all patients (the standard group 20/20 and the KODEX group 20/20). There was no difference in the mean procedure time between the two groups (63.7 ± 9.3 vs. 78.2 ± 25.1 min, p = 0.33). Compared with the standard group, the KODEX group significantly reduced the intraoperative X-ray exposure time (3.8 ± 0.5 vs. 19.3 ± 5.1 min, p < 0.05) and X-ray dose (23.6 ± 5.4 vs. 120.2 ± 38.3 mGy, p < 0.05). There were no significant differences in atrial impedance (643.0 ± 98.8 vs. 591.5 ± 92.1 Ω, p = 0.09), atrial sensing (2.9 ± 0.8 vs. 2.5 ± 0.8 mV, p = 0.08), ventricular sensing (12.8 ± 2.4 vs. 13.3 ± 3.3 mV, p = 0.63),atrial pacing threshold (1.0 ± 0.2 vs. 1.0 ± 0.1 V/0.4 ms, p = 0.81) and ventricular pacing threshold (1.0 ± 0.2 vs. 0.9 ± 0.1 V/0.4 ms, p = 0.63) between two groups, There were statistical differences in ventricular impedance (640.0 ± 80.3 vs. 702.0 ± 86.1 Ω, p < 0.05). There was no statistical significance in pacing parameters between the two groups at 6 months after procedure (p > 0.05). During the 6-months follow-up period, no adverse events occurred in the two groups. It can be concluded that KODEX-EPD can safely guide His bundle branch pacing lead implantation with reduced fluoroscopic time and dose without lengthening the procedure time.

Feasibility study of cryoballoon ablation for atrial fibrillation with KODEX-EPD: a single center experience.

To evaluate the feasibility of cryoballoon (CB) ablation of atrial fibrillation (AF) under the guidance of a new three-dimensional (3D) mapping system KODEX-EPD. 40 patients scheduled for CB ablation of AF in the first affiliated Hospital of Xinjiang Medical University from August 2021 to July 2022 were randomly divided into two groups: KODEX-EPD 3D mapping system guidance group (KODEX group, n = 20) and conventional two-dimensional perspective group (standard group, n = 20). The ablation time, operation time, fluoroscopy time, fluoroscopy dose, contrast agent dosage and follow-up data were compared between the two groups. Besides, the feasibility and accuracy of the dielectric sensing system in evaluating pulmonary vein (PV) occlusion in patients with AF during CB ablation were verified. All pulmonary veins were being isolated. The ablation time (36.40 ± 6.72 min vs 35.15 ± 6.29 min, P > 0.05) and the operation time (64.20 ± 11.82 min vs 66.00 ± 13.18 min, P > 0.05) were not statistically different in the two groups. The standard group has longer fluoroscopy time, dose and contrast medium dosage. There were significant differences in fluoroscopy time (532.30 ± 72.83 s vs 676.25 ± 269.33 s, P < 0.05), fluoroscopy dose (110.00 ± 28.64 mGy vs 144.68 ± 66.66 mGy, P < 0.05), and contrast medium dosage (71.90 ± 5.97 ml vs 76.05 ± 5.93 ml, P < 0.05) between the two groups. The learning curves of the first 5 patients and the last 15 patients in the KODEX group were compared. There was no statistical difference in the ablation time (36.80 ± 8.56 min vs 36.27 ± 6.34 min, P > 0.05) or the operation time (69.00 ± 5.00 min vs 62.60 ± 13.10 min, P > 0.05); however, compared to the first 5 patients, fluoroscopy time (587.40 ± 38.34 s vs 513.93 ± 73.02 s, P < 0.05), fluoroscopy dose (147.85 ± 35.19 mGy vs 97.39 ± 8.80 mGy, P < 0.05) and contrast medium dosage (79.60 ± 1.14 ml vs 69.33 ± 4.45 ml, P < 0.05) were significantly decreased. Using pulmonary venography as the gold standard, the sensitivity, specificity of the completely occlusion in KODEX group was 93.6% (95% CI 85-97.6%) and 69.6% (95% CI 54-81.8%); and the sensitivity, specificity of the small leak in KODEX group was 93.1% (95% CI 82.4-97.8%) and 82.0% (95% CI 65.9-91.9%). During an average follow-up of (9.90 ± 1.06) months, there was no statistical difference in arrhythmia recurrence and antiarrhythmic drugs taking after CB ablation between the two groups (P > 0.05). Using the KODEX-EPD system, the CB ablation procedure can correctly evaluate the PV occlusion, and significantly reduce fluoroscopy exposure and contrast medium without significantly increasing the operation time.