Effect of internal phase particle size on properties of site mixed emulsion explosive at plateau environment.

To study the effect of internal particle size on the microstructure properties and thermal decomposition characteristics of site mixed emulsion explosive at different altitudes. Site mixed emulsion explosive was prepared with different shear rate. The particle size, viscosity, sensitized bubbles, detonation velocity and peak pressure of the emulsion explosive were tested after stored at different simulated altitudes. The thermal decomposition characteristics of emulsion matrix prepared at three different rotational speeds were measured by thermogravimetric analyzer and kinetic analysis was performed by non-isothermal model Kissinger-Akah-Sunose (KAS) method. The results show that with the increase in altitude, the internal phase size showed a trend of first increasing and then decreasing, and the number of sensitized bubbles within the emulsion explosive decreases. At an altitude of 0 m, the detonation velocity and peak overpressure of the emulsion explosive prepared by 1600 r min-1 increased 4.78% and 29.09%, respectively compared with 1200 r min-1, and at an altitude of 4500 m, the detonation velocity increased 11.87%, the peak overpressure increased 43.98%. The thermal decomposition activation energy of the emulsion matrix at 1600 r min-1 increased 13.14% compared to 1200 r min-1. It shows that in the production of site mixed emulsion explosive at high altitude, reducing the particle size of the internal phase of emulsion explosives in a certain range can effectively improve the performance of emulsion explosives.

[Clinical characteristics and associated factors of mild cognitive impairment in patients with common cardiovascular diseases].

Objective: To analyze the clinical characteristics of patients with common cardiovascular diseases (CVD, including hypertension, coronary heart disease, atrial fibrillation, and heart failure) combined with mild cognitive impairment (MCI) and explore the potential risk factors of MCI in patients with CVD. Methods: A total of 2 294 patients with common cardiovascular diseases who met the criteria at Cardiology Medical Center in Beijing Anzhen Hospital, Capital Medical University, from June 1, 2021, to January 5, 2022, were retrospectively included. The patients were divided into the normal cognitive function group (1 107 cases) and the MCI group (1 187 cases). Demographic information and CVD status were collected. The information of cognitive function were collected using the Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE) scales. The difference between normal cognitive function and MCI were compared and analyzed. The logistic regression analysis was used to explored risk factors of MCI in CVD patients. Results: A total of 2 294 patients aged (60.6±10.4) years were included, among whom there were 29.99% (688 cases) females. Compared with patients in the normal cognitive function group, patients in the MCI group were older [ (57.9±11.4) vs (63.1±8.9) years old, P<0.001], with a higher proportion of women [26.47% (293 cases) vs 33.28% (395 cases), P<0.001]; there was a higher proportion of patients suffering from hypertension in the MCI group [59.62% (660 cases) vs 64.62% (767 cases), P=0.014ï¼½, and more components of CVD [(1.68±0.62) vs (1.74±0.65) components, P=0.017]. The risk factors of MCI in patients with common CVD were increased age, increased depression score, combined with hypertension, and ≥3 common components of CVD, with OR (95%CI) of 1.043 (1.032-1.054), 1.021 (1.004-1.037), 1.151 (1.142-3.439), and 1.137 (1.023-1.797), respectively (all P values <0.05). Increasing education level was observed to be associated with reduced risk of MCI with OR (95%CI) of 0.319 (0.271-0.378) (P<0.05). Conclusions: The incidence of MCI was high in CVD patients. The risk factors of MCI in CVD patients included hypertension and≥3 common components of CVD.

[Association between atrial fibrillation reoccurrence and new-onset ischemic stroke among patients with nonvalvular atrial fibrillation].

Objective: Explore the association between atrial fibrillation (AF) reoccurrence and new-onset ischemic stroke (IS) in patients with nonvalvular AF, and explore whether there is a high-risk period of IS after recurrent episodes of AF. Methods: A nested case-control study design was used. A total of 565 nonvalvular AF patients with new-onset IS after a follow-up of at least 2 years in the China-AF cohort were enrolled as the case group, and 1 693 nonvalvular AF patients without new-onset IS were matched as the control group at a ratio of 1∶3. Frequency and types of recurrent AF in the previous 1 or 2 years were compared between two groups, and the adjusted associations of AF reoccurrence with new onset IS were explored using conditional logistic regression analysis. The proportion of recurrent AF was compared between the case period and control period, and conditional logistic regression analysis was performed to calculate adjusted associations of case-period AF with IS. Results: The nested case-control study design results showed that the proportion of at least one record of recurrent AF in the previous 1 year was higher in the case group than in the control group (72.0% vs. 60.8%, P<0.05), and the recurrent AF was positively correlated with new-onset IS (adjusted OR=1.80, P<0.001). Similar results were also observed in the previous 2 years period. The case-crossover study design analysis showed that among 565 patients with new-onset IS, recurrent AF in the case period was positively correlated with IS (adjusted OR=1.61, P=0.003). Conclusion: Recurrent AF is associated with IS, and there may be a high-risk period of IS after recurrent episodes of AF.

[Analysis of factors associated with anxiety in patients with atrial fibrillation and their caregivers].

Objective: To explore the risk factors of anxiety in patients with atrial fibrillation and their caregivers. Methods: From September 2020 to March 2021, patients with atrial fibrillation and one primary family member as caregiver of each patient from Beijing Anzhen Hospital were enrolled. Basic data of patients and their caregivers were collected, and anxiety of patients and caregivers were evaluated by Generalized Anxiety Disorder-7 scale (GAD-7). A total of 374 patients with atrial fibrillation and their caregivers were included in this study. Multivariate logistic regression analysis was used to analyze the risk factors of anxiety of patients and their caregivers. Results: The mean age of the patients was (58.3±10.6) years, and 124 (33.2%) were female. The caregivers were (53.6±11.6) years old, and 247 (66%) were female. 69 (18.4%) patients and 38 (10.2%) caregivers had mild anxiety (GAD-7:5-9 scores), 13 (3.5%) patients and 9 (2.4%) caregivers had moderate or higher anxiety (GAD-7:10-21 scores). Multivariate analysis showed that the risk factors of anxiety in patients with atrial fibrillation included EHRA score≥3 (OR=1.73,95%CI:1.03-2.89,P=0.039) and female sex (OR=1.90,95%CI:1.06-3.40,P=0.032). EHRA score of patients≥3 (OR=2.11,95%CI:1.05-4.24, P=0.036) or anxiety of patients (OR=2.76,95%CI:1.36-5.60,P=0.005) were associated with higher anxiety of caregivers. Moreover, age of≥65 years old (OR=3.97,95%CI:1.68-9.38,P=0.002), female sex (OR=3.83,95%CI:1.64-8.93,P=0.002) and number of comorbidities of caregivers≥2 (OR=2.57,95%CI:1.03-6.41,P=0.043) were also associated with anxiety of caregivers. Conclusions: Patients with severe symptoms have a higher proportion of anxiety, and their caregivers are more likely to experience anxiety. Anxiety rate is higher in caregivers of patients with anxiety.

[Analysis of dyslipidemia management status in atrial fibrillation patients with very high and high risk of atherosclerotic cardiovascular disease].

Objective: To analyze the status of statins use and low-density lipoprotein cholesterol (LDL-C) management in patients with atrial fibrillation (AF) and very high/high risk of atherosclerotic cardiovascular disease (ASCVD) from Chinese Atrial Fibrillation Registry (CAFR). Methods: A total of 9 119 patients with AF were recruited in CAFR between January 1, 2015 to December 31, 2018, patients at very high and high risk of ASCVD were included in this study. Demographics, medical history, cardiovascular risk factors, and laboratory test results were collected. In patients with very high-risk, a threshold of 1.8 mmol/L was used as LDL-C management target and in patients with high risk, a threshold of 2.6 mmol/L was used as LDL-C management target. Statins use and LDL-C compliance rate were analyzed, multiple regression analysis was performed to explore the influencing factors of statins use. Results: 3 833 patients were selected (1 912 (21.0%) in very high risk of ASCVD group and 1 921 (21.1%) in high risk of ASCVD group). The proportion of patients with very high and high risk of ASCVD taking statins was 60.2% (1 151/1 912) and 38.6% (741/1 921), respectively. Attainment rate of LDL-C management target in patients with very high and high risk were 26.7% (511/1 912) and 36.4% (700/1 921), respectively. Conclusion: The proportion of statins use and attainment rate of LDL-C management target are low in AF patients with very high and high risk of ASCVD in this cohort. The comprehensive management in AF patients should be further strengthened, especially the primary prevention of cardiovascular disease in AF patients with very high and high risk of ASCVD.

[Current use of oral anticoagulation therapy and influencing factors among coronary artery disease patients with nonvalvular atrial fibrillation in China].

Objective: To investigate current use of oral anticoagulant (OAC) therapy and influencing factors among coronary artery disease (CAD) patients with nonvalvular atrial fibrillation (NVAF) in China. Methods: Results of this study derived from "China Atrial Fibrillation Registry Study", the study prospectively enrolled atrial fibrillation (AF) patients from 31 hospitals, and patients with valvular AF or treated with catheter ablation were excluded. Baseline data such as age, sex and type of atrial fibrillation were collected, and drug history, history of concomitant diseases, laboratory results and echocardiography results were recorded. CHA2DS2-VASc score and HAS-BLED score were calculated. The patients were followed up at the 3rd and 6th months after enrollment and every 6 months thereafter. Patients were divided according to whether they had coronary artery disease and whether they took OAC. Results: 11 067 NVAF patients fulfilling guideline criteria for OAC treatment were included in this study, including 1 837 patients with CAD. 95.4% of NVAF patients with CAD had CHA2DS2-VASc score≥2, and 59.7% of patients had HAS-BLED≥3, which was significantly higher than NVAF patients without CAD (P<0.001). Only 34.6% of NVAF patients with CAD were treated with OAC at enrollment. The proportion of HAS-BLED≥3 in the OAC group was significantly lower than in the no-OAC group (36.7% vs. 71.8%, P<0.001). After adjustment with multivariable logistic regression analysis, thromboembolism(OR=2.48,95%CI 1.50-4.10,P<0.001), left atrial diameter≥40 mm(OR=1.89,95%CI 1.23-2.91,P=0.004), stain use (OR=1.83,95%CI 1.01-3.03, P=0.020) and ß blocker use (OR=1.74,95%CI 1.13-2.68,P=0.012)were influence factors of OAC treatment. However, the influence factors of no-OAC use were female(OR=0.54,95%CI 0.34-0.86,P=0.001), HAS-BLED≥3 (OR=0.33,95%CI 0.19-0.57,P<0.001), and antiplatelet drug(OR=0.04,95%CI 0.03-0.07,P<0.001). Conclusion: The rate of OAC treatment in NVAF patients with CAD is still low and needs to be further improved. The training and assessment of medical personnel should be strengthened to improve the utilization rate of OAC in these patients.

[Chinese consensus on the use of antiarrhythmic drugs for rhythm control in atrial fibrillation].

Rhythm control is crucial part of comprehensive management of atrial fibrillation (AF). Rhythm control can reduce the burden of AF effectively, reduce symptoms, and improve the prognosis in early AF. Antiarrhythmic drugs (AADs) are the first-line treatment for rhythm-control strategies. This consensus focuses on the principle of rhythm control in AF, the characteristics of AADs, and the medication recommendations for patients in different populations suffering from AF. Hence, this consensus aims to support clinical decision-making for AF therapy.

[The timing of pericardial drainage catheter removal and restart of the anticoagulation in patients suffered from perioperative pericardial tamponade during atrial fibrillation catheter ablation and uninterrupted dabigatran: Experiences from 20 cases].

Objective: To investigate the timing of pericardial drainage catheter removal and restart of the anticoagulation in patients with atrial fibrillation (AF) suffered from perioperative pericardial tamponade during atrial fibrillation catheter ablation and uninterrupted dabigatran. Methods: A total of 20 patients with pericardial tamponade, who underwent AF catheter ablation with uninterrupted dabigatran in Beijing Anzhen Hospital from January 2019 to August 2021, were included in this retrospective analysis. The clinical characteristics of enrolled patients, information of catheter ablation procedures, pericardial tamponade management, perioperative complications, the timing of pericardial drainage catheter removal and restart of anticoagulation were analyzed. Results: All patients underwent pericardiocentesis and pericardial effusion drainage was successful in all patients. The average drainage volume was (427.8±527.4) ml. Seven cases were treated with idarucizumab, of which 1 patient received surgical repair. The average timing of pericardial drainage catheter removal and restart of anticoagulation in 19 patients without surgical repair was (1.4±0.7) and (0.8±0.4) days, respectively. No new bleeding, embolism and death were reported during hospitalization and within 30 days following hospital discharge. Time of removal of pericardial drainage catheter, restart of anticoagulation and hospital stay were similar between patients treated with idarucizumab or not. Conclusion: It is safe and reasonable to remove pericardial drainage catheter and restart anticoagulation as soon as possible during catheter ablation of atrial fibrillation with uninterrupted dabigatran independent of the idarucizumab use or not in case of confirmed hemostasis.

[Efficacy and safety of radiofrequency catheter ablation of septal hypertrophy guided by intracardiac echocardiography in hypertrophic obstructive cardiomyopathy].

Nine patients identified as hypertrophic obstructive cardiomyopathy (HOCM) in Beijing Anzhen Hopspital who underwent ablation from March to July 2019 were included in the study. All patients had left ventricular outflow tract gradient (LVOTG) over 50 mmHg(1 mmHg=0.133 kPa)with significant symptoms despite not optimal drug therapy. Intracardiac echocardiography (ICE) was used to reconstruct septum and surrounding structures, and monitor the effect of ablation during procedure. Nine patients with HOCM were included,.of which 6 men and 3 women. The average age was (51.7±12.2) years. All patients underwent successful ablation after a mean of procedural time of (152.2±31.9) minutes and ablation time of (838.4±227.3) seconds. Except for one patients, all other patients had significant LVOTG reduction(P=0.001)within 50 mmHg after the procedure. Systolic anterior motion of the mitral valve disappeared in all patients after the procedure without major periprocedural complications. The LVOTG of these patients remained stable during follow-up. Radiofrequency ablation using ICE guidance is feasible in treating HOCM with promising efficacy and safety.

[A comparison of CAS risk model and CHA2DS2-VASc risk model in guiding anticoagulation treatment in Chinese patients with non-valvular atrial fibrillation].

Objective: To compare the differences between CAS risk model and CHA2DS2-VASc risk score in predicting all cause death, thromboembolic events, major bleeding events and composite endpoint in patients with nonvalvular atrial fibrillation. Methods: This is a retrospective cohort study. From the China Atrial Fibrillation Registry cohort study, the patients with atrial fibrillation who were>18 years old were randomly divided into CAS risk score group and CHA2DS2-VASc risk score group respectively. According to the anticoagulant status at baseline and follow-up, patients in the 2 groups who complied with the scoring specifications for anticoagulation were selected for inclusion in this study. Baseline information such as age and gender in the two groups were collected and compared. Follow-up was performed periodically to collect information on anticoagulant therapy and endpoints. The endpoints were all-cause death, thromboembolism events and major bleeding, the composite endpoint events were all-cause death and thromboembolism events. The incidence of endpoints in CAS group and CHA2DS2-VASc group was analyzed, and multivariate Cox proportional risk model was used to analyze whether the incidence of the endpoints was statistically different between the two groups. Results: A total of 5 206 patients with AF were enrolled, average aged (63.6±12.2) years, and 2092 (40.2%) women. There were 2 447 cases (47.0%) in CAS risk score group and 2 759 cases (53.0%) in CHA2DS2-VASc risk score group. In the clinical baseline data of the two groups, the proportion of left ventricular ejection fraction<55%, non-paroxysmal atrial fibrillation, oral warfarin and HAS BLED score in the CAS group were lower than those in the CHA2DS2-VASc group, while the proportion of previous diabetes history and history of antiplatelet drugs in the CAS group was higher than that in the CHA2DS2-VASc group, and there was no statistical difference in other baseline data. Patients were followed up for (82.8±40.8) months. In CAS risk score group, 225(9.2%) had all-cause death, 186 (7.6%) had thromboembolic events, 81(3.3%) had major bleeding, and 368 (15.0%) had composite endpoint. In CHA2DS2-VASc risk score group, 261(9.5%) had all-cause death 209(7.6%) had thromboembolic events, 112(4.1%) had major bleeding, and 424 (15.4%) had composite endpoint. There were no significant differences in the occurrence of all-cause death, thromboembolic events, major bleeding and composite endpoint between anticoagulation in CAS risk score group and anticoagulation in CHA2DS2-VASc risk score group (log-rank P =0.643, 0.904, 0.126, 0.599, respectively). Compared with CAS risk score, multivariable Cox proportional hazards regression models showed no significant differences for all-cause death, thromboembolic events, major bleeding and composite endpoint between the two groups with HR(95%CI) 0.95(0.80-1.14), 1.00(0.82-1.22), 0.83(0.62-1.10), 0.96(0.84-1.11), respectively. All P>0.05. Conclusions: There were no significant differences between CAS risk model and CHA2DS2-VASc risk score in predicting all-cause death, thromboembolic events, and major bleeding events in Chinese patients with non-valvular atrial fibrillation.

[Use of oral anticoagulants and related factors among new-onset acute ischemic stroke patients with nonvalvular atrial fibrillation: A report from the China Atrial Fibrillation Registry Study].

Objective: This study aimed to investigate the oral anticoagulant (OAC) usage among new-onset acute ischemic stroke (AIS) patients with nonvalvular atrial fibrillation (NVAF) in China, and to explore the possible influencing factors of influent anticoagulant therapy in these patients. Methods: The NVAF patients who experienced new-onset and non-fatal AIS from August 2011 to December 2018 in the China Atrial Fibrillation Registry (China-AF), were enrolled. The follow-up ended in December 2019. Information including patients' demographic characteristics, medical history, medication usage, which were collected before and after the index stroke, were analyzed. Patients were classified into OAC group or non-OAC group according to OAC usage within 3 months post stroke. Multivariate logistic regression analysis were conducted to calculate the odds ratios (ORs) of factors which might be associated with OAC usage within 3 months post stroke. Results: A total of 957 new-onset AIS patients were enrolled, 39.4% (377/957) patients were treated with OAC within 3 months after AIS. Covering by high-reimbursement-rate insurance (OR: 1.91, 95%CI: 1.28-2.86, P=0.002), higher number of concomitant drugs (1-2 types OR: 2.10, 95%CI: 1.36-3.23, P=0.001; ≥3 types OR: 2.31, 95%CI: 1.37-3.91, P=0.002) and 3-month-peri-stroke AF recurrence (OR: 3.34, 95%CI: 2.34-4.76, P<0.001) were associated with OAC usage within 3 months post stroke, while higher HASBLED score (OR: 0.49, 95%CI: 0.40-0.60, P<0.001) and pre-stroke antiplatelet usage (OR: 0.29, 95%CI: 0.20-0.43, P<0.001) were related to no OAC usage within 3 months post stroke. Conclusions: In China, the proportion of NVAF patients who initiated OAC therapy within 3 months after new-onset AIS is as low as about 39.4%. Factors related to the OAC usage within 3 months post stroke are 3-month-peri-stroke AF recurrence, number of concomitant drugs and patients with high-reimbursement-rate insurance coverage, but higher HASBLED score and pre-stroke antiplatelet usage are related to no OAC usage within 3 months post stroke.