Activation of PKC affects the ventricular restitution properties and arrhythmogenesis through L-type Ca+ current.

OBJECTIVE: To investigate the role of protein kinase C (PKC) in action potential duration (APD) restitution and ventricular tachyarrhythmias (VAs). METHODS AND RESULTS: Rabbits hearts were isolated and prepared for Langendorff perfusion technique. The stimuli-extra-stimulus (S1-S2) method and dynamic S1 pacing protocol were performed to construct APD restitution and to induce APD alternans or VA, respectively, at 10 sites throughout the ventricular chamber. Administration of phorbol-12-myristate-13-acetate (PMA) (100 nM) (n = 15) greatly steepened the restitution curves (Smax > 1) (p < .01) at each site compared to the control group (n = 15). Furthermore, treatment with PMA also induced larger spatial dispersions of Smax (p < .05) and decreased the thresholds of the VA and APD alternans (p < .01). However, perfused with the PKC inhibitor, bisindolylmaleimide (BIM) (500 nM) (n = 10), reversibly flattened the APD restitution curves at each site (Smax < 1), decreased the spatial dispersions of Smax, and increased the thresholds of APD alternans and VA. According to the results of patch-clamp, peak amplitude of L-type Ca2+ current was significantly increased by addition of PMA compared with control (CTL) group (p < .05). Antagonize this current with verapamil (n = 10) can fully inhibited the PMA induced increasing of Smax and inducibility of VA and alternans. CONCLUSION: PKC activation increased the dispersion of APD restitution and thus led to occurrence of VA, which possibly related to the increased Ca2+ influx.

Short-term dietary teprenone improved thermal tolerance and mitigated liver damage caused by heat stress in juvenile largemouth bass (Micropterus salmoides).

Heat stress seriously threatens fish survival and health, demanding immediate attention. Teprenone is a gastric mucosal protective agent that can induce heat shock protein expression. This research investigated the effects of teprenone on largemouth bass (Micropterus salmoides) subjected to heat stress. Juvenile fish were assigned to different groups: group C (control group, 0 mg teprenone/kg diet), T0, T200, T400, and T800 (0, 200, 400, and 800 mg teprenone/kg diet, respectively), which were fed for 3 days, followed by a day without the diet. All groups except group C were subjected to acute heat stress (from 24 °C to 35 °C at 1 °C per hour and then maintained at 35 °C for 3 h). The results were as follows: The critical thermal maxima were significantly higher in the T200, T400, and T800 groups compared with the T0 group (P < 0.05). Heat stress caused severe damage to the tissue morphology of the liver, while teprenone significantly reduced this injury (P < 0.05). Serum cortisol concentration decreased gradually as teprenone concentration increased, and the lowest concentration was observed in the T800 group (P < 0.05). Compared with the T0 group, the serum activities of aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyl transferase were significantly lower in the T200, T400, and T800 groups (P < 0.05). The liver activities of catalase, total superoxide dismutase, and peroxidase were significantly higher in the T200 group than in the T0 group (P < 0.05). Transcript levels of the heat shock proteins (hsp90, hsp70, hspa5, and hsf1) and caspase family (caspase3 and caspase9) in the liver of the T200 group were significantly higher than those of the T0 group (P < 0.05). Western blot results showed that HSP70 and HSPA5 in the liver were significantly upregulated in the T200 group compared with the T0 group (P < 0.05). In summary, dietary teprenone improved thermal tolerance, alleviated heat stress damage in the liver, enhanced antioxidant capacity, and upregulated heat shock proteins in juvenile largemouth bass. This study offers theoretical support for applying teprenone in aquaculture to reduce financial losses caused by abiotic factors.

Value of the monocyte-to-high-density lipoprotein cholesterol ratio in refining the detection of prevalent heart failure: Insights from the NHANES 1999-2018.

The monocyte-to-high-density lipoprotein cholesterol ratio (MHR) is a novel marker that can help estimate the degree of atherosclerosis by considering inflammation and lipid abnormalities. This study aimed to assess the association between the MHR and prevalent heart failure (HF) and to explore the value of the MHR in detecting prevalent HF in the general US population. Our study included 25,374 participants from the National Health and Nutrition Examination Survey (1999-2018). Among the participants, 749 (2.95%) reported a history of HF, and the HF group had a significantly higher MHR than the non-HF group. Adjusted analyses revealed that each standard deviation increase in the MHR was associated with a 27.8% increase in the risk of HF. The association between the MHR and prevalent HF was linear across the entire MHR range. Adding the MHR to conventional cardiovascular risk factors significantly improved the area under the curve (0.875; p < 0.001), continuous net reclassification index (0.187; p < 0.001), and integrated discrimination index (0.004; p < 0.001). Our study suggests a potential association between the MHR and HF risk, and the findings enhance HF risk stratification and provide novel insights into the interplay between the coronary atherosclerotic burden and HF in clinical settings.

Adjunctive Right Atrial Ablation for Persistent Atrial Fibrillation With Right Atrial Enlargement: A Pilot Study.

BACKGROUND: Persistent atrial fibrillation (PerAF) is often associated with right atrial (RA) enlargement. We investigated the efficacy of RA intervention in patients with PerAF and RA enlargement. METHODS: Patients with PerAF and RA enlargement were randomised (1:1) to receive adjunctive RA ablation (left atrial [LA] + RA group; n = 60) or to receive LA ablation alone (LA-only group; n = 60). In the LA + RA group, RA ablation was performed if LA ablation failed to terminate AF. The primary end point was freedom from AF/atrial tachycardia (AT) recurrence at 12 months after a single ablation procedure without antiarrhythmic drug therapy. RESULTS: In the LA + RA group, 40 patients (67%) required RA ablation. The LA + RA group had a higher rate of acute AF termination than the LA-only group (63.3% vs 36.7%; P = 0.003). At the end of 12-month follow-up, 42 patients (70%) in the LA + RA group were free of AF/AT recurrence, compared with 31 (51.7%) in the LA-only group (log rank P = 0.034; hazard ratio 0.549, 95% confidence interval 0.310-0.974). The rate of freedom from AF recurrence was also higher in the LA + RA group than in the LA-only group (81.7% vs 63.3%; log rank P = 0.019). The 2 groups had similar rates of adverse events (5% vs 3.3%; P = 0.648). CONCLUSIONS: Adjunctive RA ablation increased the success rate of a single ablation in patients with PerAF and RA enlargement. CHINESE CLINICAL TRIAL REGISTRATION: ChiCTR220056844.

Multi-centre, prospective randomized comparison of three different substrate ablation strategies for persistent atrial fibrillation.

AIMS: The optimal strategy for persistent atrial fibrillation (PerAF) is poorly defined. We conducted a multicentre, randomized, prospective trial to compare the outcomes of different ablation strategies for PerAF. METHODS AND RESULTS: We enrolled 450 patients and randomly assigned them in a 1:1:1 ratio to undergo pulmonary vein isolation and subsequently undergo the following three different ablation strategies: anatomical guided ablation (ANAT group, n = 150), electrogram guided ablation (EGM group, n = 150), and extensive electro-anatomical guided ablation (EXT group, n = 150). The primary endpoint was freedom from atrial fibrillation (AF) lasting longer than 30 s at 12 months after a single ablation procedure. After 12 months of follow-up, 72% (108) of patients in the EXT group were free from AF recurrence, as compared with the 64% (96) in the EGM group (P = 0.116), and 54% (81) in the ANAT group (P = 0.002). The EXT group showed less AF/atrial tachycardia recurrence than the EGM group (60% vs. 50%, P = 0.064) and the ANAT group (60% vs. 37.3%, P < 0.001). The EXT group showed the highest rate of AF termination (66.7%), followed by 56.7% in the EGM group, and 20.7% in the ANAT group. The AF termination signified less AF recurrence at 12 months compared to patients without AF termination (30.1% vs. 42.7%, P = 0.008). Safety endpoints did not differ significantly between the three groups (P = 0.924). CONCLUSIONS: Electro-anatomical guided ablation achieved the most favourable outcomes among the three ablation strategies. The AF termination is a reliable ablation endpoint.

Temporal and Spatial Changes of Proarrhythmic Substrate in Premature Ventricular Contraction-Induced Cardiomyopathy.

BACKGROUND: The changes in proarrhythmic substrates and malignant ventricular arrhythmia mechanisms caused by premature ventricular contraction-induced cardiomyopathy (PVCCM) remain unclear. OBJECTIVES: The goal of this study was to establish the electrophysiological mechanism of how high-load PVC causes malignant arrhythmia. METHODS: Thirteen swine were exposed to 50% paced PVC from the right ventricular apex for 12 weeks (PVCCM, n = 6) and no pacing for 12 weeks (control, n = 7). Cardiac function was quantified biweekly with echocardiography. Computed tomography scans and electrophysiological examinations were performed monthly to dynamically evaluate the changes in the cardiac structure and the arrhythmogenic substrate. RESULTS: The decreases in the cardiac function and ventricular enlargement in the PVCCM group were significant after 12 weeks of PVC stimulation compared with the control group (P < 0.001). Electrophysiological examination found that the ventricular effective refractory period dispersion (0.071 ± 0.008), area of the low-voltage zone (9.41 ± 1.55 cm2), and malignant ventricular arrhythmia inducibility (33.3%) of the PVCCM group increased significantly at week 8 after pacing (P < 0.001 vs the control group); these changes slowed down after 8 weeks. Moreover, the distribution of the low-voltage zone presented obvious spatial heterogeneity, especially in the anterior wall of the right ventricle, accompanied by delayed activation in the sinus rhythm (67 ± 13 milliseconds). Consistently, the proportion of ventricular fibrosis- and expression-related proteins were significantly increased in the PVCCM group (P < 0.001), especially in the right ventricle. Moreover, proteomic analysis confirmed the spatial profile of these fibrotic changes in the PVCCM group. CONCLUSIONS: High-burden PVC can cause significant temporal and spatial heterogeneity changes in proarrhythmic substrates, which are potentially related to the upregulation of calcium signaling caused by asynchronous activation.

Rotor mechanism and its mapping in atrial fibrillation.

Treatment of atrial fibrillation (AF) remains challenging despite significant progress in understanding its underlying mechanisms. The first detailed, quantitative theory of functional re-entry, the 'leading circle' model, was developed more than 40 years ago. Subsequently, in decades of study, an alternative paradigm based on spiral waves has long been postulated to drive AF. The rotor as a 'spiral wave generator' is a curved 'vortex' formed by spin motion in the two-dimensional plane, identified using advanced mapping methods in experimental and clinical AF. However, it is challenging to achieve complementary results between experimental results and clinical studies due to the limitation in research methods and the complexity of the rotor mechanism. Here, we review knowledge garnered over decades on generation, electrophysiological properties, and three-dimensional (3D) structure diversity of the rotor mechanism and make a comparison among recent clinical approaches to identify rotors. Although initial studies of rotor ablation at many independent centres have achieved promising results, some inconclusive outcomes exist in others. We propose that the clinical rotor identification might be substantially influenced by (i) non-identical surface activation patterns, which resulted from a diverse 3D form of scroll wave, and (ii) inadequate resolution of mapping techniques. With rapidly advancing theoretical and technological developments, future work is required to resolve clinically relevant limitations in current basic and clinical research methodology, translate from one to the other, and resolve available mapping techniques.

Value of estimated glucose disposal rate to detect prevalent left ventricular hypertrophy: implications from a general population.

BACKGROUND: Insulin resistance plays a pivotal role in developing left ventricular hypertrophy (LVH). Researchers have identified the estimated glucose disposal rate (eGDR) as a simple and cost-effective surrogate of insulin resistance. Our work aims to investigate the association between eGDR and the prevalent LVH and explore the incremental value of eGDR to detect prevalent LVH. METHODS: The present work enrolled 3839 subjects from a cross-sectional survey conducted between October 2019 to April 2020 in the rural areas of southeastern China. eGDR was calculated based on waist-to-hip circumference ratio, hypertension, and glycated hemoglobin. RESULTS: The prevalence of LVH was 17.30%. After adjusting demographic, anthropometric, laboratory, and medical history co-variates, each standard deviation increase of eGDR decreased a 29.6% risk of prevalent LVH. When dividing eGDR into quartiles, the top quartile had a 38.4% risk compared to the bottom quartile. Moreover, smooth curve fitting revealed that the association between eGDR and prevalent LVH was linear in the whole range of eGDR. Additionally, subgroup analysis demonstrated that our main finding was robust to age, sex, BMI, hypertension, and diabetes subgroups. Finally, ROC analysis exhibited a significant improvement by adding eGDR into LVH risk factors (0.780 vs. 0.803, P < 0.001), and category-free net reclassification index (0.702, P < 0.001) and integrated discrimination index (0.027, P < 0.001) also confirmed the improvement from eGDR to detect prevalent LVH. CONCLUSION: Our analysis revealed a linear, robust association between eGDR and prevalent LVH and demonstrated the incremental value of eGDR to optimize the detection of prevalent LVH.

A novel approach for quantitative electrogram analysis for driver identification: Implications for ablation in persistent atrial fibrillation.

Objective: This study sought to study the feasibility, efficacy, and safety of using multiscale entropy (MSE) analysis to guide catheter ablation for persistent atrial fibrillation (PsAF) and predict ablation outcomes. Methods: We prospectively enrolled 108 patients undergoing initial ablation for PsAF. MSE was calculated based on bipolar intracardiac electrograms (iEGMs) to measure the dynamical complexity of biological signals. The iEGMs data were exported after pulmonary vein isolation (PVI), then calculated in a customed platform, and finally re-annotated into the CARTO system. After PVI, regions of the highest mean MSE (mMSE) values were ablated in descending order until AF termination, or three areas had been ablated. Results: Baseline characteristics were evenly distributed between the AF termination (n = 38, 35.19%) and the non-termination group. The RA-to-LA mean MSE (mMSE) gradient demonstrated a positive gradient in the non-termination group and a negative gradient in the termination group (0.105 ± 0.180 vs. -0.235 ± 0.256, P < 0.001). During a 12-month follow-up, 29 patients (26.9%) had arrhythmia recurrence after single ablation, and 18 of them had AF (62.1%). The termination group had lower rates of arrhythmia recurrence (15.79 vs. 32.86%, Log-Rank P = 0.053) and AF recurrence (10.53 vs. 20%, Log-Rank P = 0.173) after single ablation and a lower rate of arrhythmia recurrence (7.89 vs. 27.14%, Log-Rank P = 0.018) after repeated ablation. Correspondingly, subjects with negative RA-to-LA mMSE gradient had lower incidences of arrhythmia (16.67 vs. 35%, Log-Rank P = 0.028) and AF (16.67 vs. 35%, Log-Rank P = 0.032) recurrence after single ablation and arrhythmia recurrence after repeated ablation (12.5 vs. 26.67%, Log-Rank P = 0.062). Marginal peri-procedural safety outcomes were observed. Conclusion: MSE analysis-guided driver ablation in addition to PVI for PsAF could be feasible, efficient, and safe. An RA < LA mMSE gradient before ablation could predict freedom from arrhythmia. The RA-LA MSE gradient could be useful for guiding ablation strategy selection.

Usefulness of Triglyceride-glucose index for detecting prevalent atrial fibrillation in a type 2 diabetic population.

OBJECTIVES: Atrial fibrillation (AF) is the most common arrhythmias, which significantly jeopardizes global cardiovascular health through the complicated heart failure and stroke. Published studies have demonstrated the impact of insulin resistance on the genesis of AF. Hence, monitoring insulin resistance may be a possible way to improve the detection of early-stage AF. Accordingly, our work aimed to investigate the association between TyG, a surrogate of insulin resistance, and the prevalent AF, and to evaluate the potential of TyG to refine the detection of prevalent AF in a diabetic population. METHODS: This cross-sectional study was derived from the National Metabolic Management Center Program and included 3244 diabetic patients between September 2017 and December 2020. TyG was calculated as ln[fasting TG (mg/ dL)× FPG (mg/dL)/2]. AF was diagnosed according to electrocardiography and subjects' self-reports. RESULTS: The prevalence of AF was 6.57%. In the fully adjusted model, each SD elevation of TyG cast a 40.6% additional risk for prevalent AF. In the quartile analysis, the top quartile showed a 2.120 times risk of prevalent AF compared with the bottom quartile. Smooth curve fitting demonstrated that the association was linear in the full range of TyG, and subgroup analysis suggested that the association was robust in several common subpopulations of AF. Furthermore, ROC results displayed an improvement for the detection of prevalent AF when adding TyG into conventional cardiovascular risk factors (0.812vs.0.825, P = 0.019), and continuous net reclassification index (0.227, 95% CI: 0.088-0.365, P = 0.001) and integrated discrimination index (0.007, 95% CI: 0.001-0.012, P = 0.026) also showed the improvement achieved by TyG. CONCLUSION: Our data supported a linear and robust correlation between TyG and the prevalent AF in a diabetic population. Moreover, our results implicated the potential usefulness of TyG to refine the detection of prevalent AF in a diabetic population.

Is rosuvastatin protective against sepsis-associated encephalopathy? A secondary analysis of the SAILS trial.

BACKGROUND: Sepsis is a common cause of death in emergency departments and sepsis-associated encephalopathy (SAE) is a major complication. Rosuvastatin may play a neuroprotective role due to its protective effects on the vascular endothelium and its anti-inflammatory functions. Our study aimed to explore the potential protective function of rosuvastatin against SAE. METHODS: Sepsis patients without any neurological dysfunction on admission were prospectively enrolled in the "Rosuvastatin for Sepsis-Associated Acute Respiratory Distress Syndrome" study (SAILS trial, ClinicalTrials.gov number: NCT00979121). Patients were divided into rosuvastatin and placebo groups. This is a secondary analysis of the SAILS dataset. Baseline characteristics, therapy outcomes, and adverse drug events were compared between groups. RESULTS: A total of 86 patients were eligible for our study. Of these patients, 51 were treated with rosuvastatin. There were significantly fewer cases of SAE in the rosuvastatin group than in the placebo group (32.1% vs. 57.1%, P=0.028). However, creatine kinase levels were significantly higher in the rosuvastatin group than in the placebo group (233 [22-689] U/L vs. 79 [12-206] U/L, P=0.034). CONCLUSION: Rosuvastatin appears to have a protective role against SAE but may result in a higher incidence of adverse events.

[Removal Characteristics of Four Typical Antibiotics in Denitrification System].

Wastewater treatment plants are an important gathering place for antibiotics, where denitrification plays a vital role in biological nitrogen removal. In order to explore the removal characteristics of antibiotics in a denitrifying sludge system, norfloxacin (NOR), oxytetracycline (OTC), sulfamethoxazole (SMX), and trimethoprim (TMP) were selected to investigate their transformation under different carbon source conditions in a denitrification system. The contribution of adsorption and biodegradation for antibiotic removal was also evaluated in this study. The results showed that a certain proportion of NOR, OTC, and TMP could be removed by denitrification, whereas NOR and OTC could act as the sole carbon source for denitrification. The removal of NOR and OTC showed a rapid adsorption and then slow biodegradation trend in the denitrification system. The contributions of adsorption were recorded as 83.5% and 58.9% for NOR and OTC removal, respectively. More than 40% were adsorbed by extracellular polymer substances (EPS), whereas the P450 enzyme played an important role in the OTC biodegradation process, with a contribution of 20%.

Value of estimated pulse wave velocity to identify left ventricular hypertrophy prevalence: insights from a general population.

BACKGROUND: Aortic stiffness shares a similar profile of risk factors with left ventricular hypertrophy (LVH) and can also lead to LVH by itself. Published data have demonstrated the correlation between aortic stiffness and LVH. Recent data have revealed estimated pulse wave velocity (ePWV) to be a simple and cost-effective marker of the severity of aortic stiffness. Our analysis aimed to explore the association between ePWV and LVH prevalence, and to investigate the incremental value of ePWV for the identification of LVH prevalence. METHODS: The present analysis based on a cross-sectional survey which included 11,597 participants from rural areas of southeastern China between Sep 2020 and Feb 2021. ePWV was formulated based on mean blood pressure and age according to a published algorithm. RESULTS: The prevalence of LVH was 14.56%. With the adjustment of age, sex, education, income and physical activity level, current drinking and smoking status, BMI, waist circumference, serum creatinine, total cholesterol, high density cholesterol, mean blood pressure, fasting plasma glucose, anti-hypertensive therapy, anti-diabetic therapy, lipid-lowering therapy, and cardiovascular disease history, every standard deviation increment of ePWV associated with a 2.993 times risk of LVH prevalence. When dividing ePWV into quartiles, the top quartile had a 4.520 times risk of LVH prevalence when compared with the bottom quartile. Furthermore, smooth spline analysis displayed that the association was linear in the whole range of ePWV (p for non-linearity = 0.073). Additionally, subgroup analysis revealed the association was robust to sex, obesity and diabetes, and younger people and hypertensive population were more vulnerable to the increase of ePWV than their corresponding counterparts. Finally, ROC analysis showed a significant advancement when introducing ePWV into established risk factors (0.787 vs. 0.810, p for comparison < 0.001), and reclassification analysis also confirmed significant improvement from ePWV to identify LVH prevalence (category-free net reclassification analysis = 0.421, p < 0.001; integrated discrimination index = 0.023, p < 0.001). CONCLUSION: Our analysis demonstrated a linear association between ePWV and LVH prevalence. Furthermore, our results suggest younger people and hypertensive population are more likely to have LVH prevalence with the increase of ePWV. More importantly, our findings implicate the incremental value of ePWV to optimize the identification of LVH prevalence in a general Chinese population.

Right atrial appendage: an important structure to drive atrial fibrillation.

PURPOSE: Understanding of the atrial fibrillation (AF) driven by right atrial appendage (RAA) is limited. This study aimed to understand the characteristics of the AF driven by RAA and explore ablation methods. METHODS: This was a retrospective study and patients who were identified as having the AF driven by RAA were reviewed. Ablation was performed during AF. Potential maps of the left and right atrium, electrophysiological examinations, and ablation methods were studied. RESULTS: Among the 20 identified patients (mean age 67.0 ± 11.2 years; ejection fraction 62.9 ± 6.0%; LA diameter 43.1 ± 4.9 mm; RA diameter 51.7 ± 8.3 × 42.9 ± 3.7 mm), the AF cycle length in RAA (134.0 ± 10.9 ms) was the shortest, and the fastest frequency potentials were located in the RAA in 65% of patients. For the left atrium, the AF cycle length of the roof (145.5 ± 14.9 ms) was the shortest, followed by the left atrial appendage (153.7 ± 17.1 ms) and bottom (154.8 ± 11.8 ms). High-frequency potentials of RAA could be rapidly conducted to left atrium via sagittal bundle and Bachmann's bundle, and the conduction time (55.0 ± 5.0 ms) was significantly shorter than the mean bi-atrial activation time (176.7 ± 10.3 ms, P < 0.0001). AF could be terminated after ablation at the RAA base (17 patients) or mechanical stimulation within the RAA (3 patients). To date, only two patients had recurrent atrial flutter, while the remaining patients maintained sinus rhythm. CONCLUSION: The AF driven by RAA is characterized by high-frequency potentials in RAA, and ablation at the RAA base can achieve a satisfactory therapeutic effect.

Role and mechanism of lncRNA under magnetic nanoparticles in atrial autonomic nerve remodeling during radiofrequency ablation of recurrent atrial fibrillation.

It aimed to investigate the mechanism of magnetic nanoparticles (MNPs) on atrial fibrillation and effect of n-isopropyl acrylamide coated MNPs (NIPA-co-MN) on the treatment of atrial fibrillation. Ten beagles weighing 20 - 25 kg were randomly divided into test group and control group. Dogs with atrial fibrillation were set as test group, and non-atrial fibrillation dogs as control group. The expression of long non-coding RNA (lncRNA) differentially expressed in the right anterior adipose pad in atrial fibrillation and non-atrial fibrillation dogs was detected by high-throughput sequencing. The relationship between lncRNA and cardiac autonomic nerve remodeling (CANR) was explored. In addition, 20 beagles weighing 20-25 kg were selected to study the therapeutic effect of n-isopropylacrylamide magnetic nanoparticles (NIPA-co-MN) on atrial fibrillation, and statistical analysis was performed. The volume and number of new neurons in the anterior right fat pad of atrium of test group were larger than the control group. The test group dogs produced 45 brand-new lncRNA, including 15 up-regulated transcripts and 30 down-regulated transcripts. MNPs injection can slow down the reduction of ventricular rate in right inferior ganglion plexus. The anterior right ganglion plexus resulted in a reduced amplitude of sinus tachyarrhythmia. This study provided references for the discovery of new diagnostic biomarkers or therapeutic targets and for the treatment of patients with atrial fibrillation.

Development of an intensive simulating training program in emergency medicine for medical students in China.

BACKGROUND: A national standardized emergency medicine (EM) curriculum for medical students, including specific competencies in procedural skills, are absent in many countries. The development of an intensive simulating training program in EM, based on a tight schedule, is anticipated to enhance the competency of medical students. METHODS: A 3-day intensive EM training program, consisting of four procedural skills and 8-hour case-based learning (CBL), was developed by experienced physicians from the EM department in Peking Union Medical College Hospital (PUMCH). Medical students from Peking Union Medical College (PUMC) and Tsinghua University (THU) participated in the training. Three written tests were cautiously designed to examine the short-term (immediately after the program) and long-term (6 months after the program) efficacy of the training. After completion of the training program, an online personal appraisal questionnaire was distributed to the students on WeChat (a mobile messaging App commonly used in China) to achieve anonymous self-evaluation. RESULTS: Ninety-seven out of 101 students completed the intensive training and took all required tests. There was a significant increase in the average score after the intensive simulating training program (pre-training 13.84 vs. 15.57 post-training, P<0.001). Compared with the pre-training test, 63 (64.9%) students made progress. There was no significant difference in scores between the tests taken immediately after the program and 6 months later (15.57±2.22 vs. 15.38±2.37, P=0.157). Students rated a higher score in all diseases and procedural skills, and felt that their learning was fruitful. CONCLUSIONS: The introduction of a standardized intensive training program in EM focusing on key competencies can improve clinical confidence, knowledge, and skills of medical students toward the specialty. In addition, having such a program can also enhance student's interest in EM as a career choice which may enhance recruitment into the specialty and workplace planning.