Hourly Air Pollutants and Acute Coronary Syndrome Onset in 1.29 Million Patients.

BACKGROUND: Short-term exposure to ambient air pollution has been linked with daily hospitalization and mortality from acute coronary syndrome (ACS); however, the associations of subdaily (hourly) levels of criteria air pollutants with the onset of ACS and its subtypes have rarely been evaluated. METHODS: We conducted a time-stratified case-crossover study among 1 292 880 patients with ACS from 2239 hospitals in 318 Chinese cities between January 1, 2015, and September 30, 2020. Hourly concentrations of fine particulate matter (PM2.5), coarse particulate matter (PM2.5-10), nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO), and ozone (O3) were collected. Hourly onset data of ACS and its subtypes, including ST-segment-elevation myocardial infarction, non-ST-segment-elevation myocardial infarction, and unstable angina, were also obtained. Conditional logistic regressions combined with polynomial distributed lag models were applied. RESULTS: Acute exposures to PM2.5, NO2, SO2, and CO were each associated with the onset of ACS and its subtypes. These associations were strongest in the concurrent hour of exposure and were attenuated thereafter, with the weakest effects observed after 15 to 29 hours. There were no apparent thresholds in the concentration-response curves. An interquartile range increase in concentrations of PM2.5 (36.0 µg/m3), NO2 (29.0 µg/m3), SO2 (9.0 µg/m3), and CO (0.6 mg/m3) over the 0 to 24 hours before onset was significantly associated with 1.32%, 3.89%, 0.67%, and 1.55% higher risks of ACS onset, respectively. For a given pollutant, the associations were comparable in magnitude across different subtypes of ACS. NO2 showed the strongest associations with all 3 subtypes, followed by PM2.5, CO, and SO2. Greater magnitude of associations was observed among patients older than 65 years and in the cold season. Null associations of exposure to either PM2.5-10 or O3 with ACS onset were observed. CONCLUSIONS: The results suggest that transient exposure to the air pollutants PM2.5, NO2, SO2, or CO, but not PM2.5-10 or O3, may trigger the onset of ACS, even at concentrations below the World Health Organization air quality guidelines.

Hourly air pollution exposure and the onset of symptomatic arrhythmia: an individual-level case-crossover study in 322 Chinese cities.

BACKGROUND: Few studies have explored the relationship between air pollution and arrhythmia onset at the hourly level. We aimed to examine the association of exposure to air pollution with the onset of acute symptomatic arrhythmia at an hourly level. METHODS: We conducted a nationwide, time-stratified, case-crossover study in China between 2015 and 2021. We obtained hourly information on the onset of symptomatic arrhythmia (including atrial fibrillation, atrial flutter, atrial and ventricular premature beats and supraventricular tachycardia) from the Chinese Cardiovascular Association Database - Chest Pain Center (including 2025 certified hospitals in 322 cities). We obtained data on hourly concentrations of 6 air pollutants from the nearest monitors, including fine particles (PM2.5), coarse particles (PM2.5-10), nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO) and ozone. For each patient, we matched the case period to 3 or 4 control periods during the same hour, day of week, month and year. We used conditional logistic regression models to analyze the data. RESULTS: We included a total of 190 115 patients with acute onset of symptomatic arrhythmia. Air pollution was associated with increased risk of onset of symptomatic arrhythmia within the first few hours of exposure; this risk attenuated substantially after 24 hours. An interquartile range increase in PM2.5, NO2, SO2 and CO in the first 24 hours after exposure (i.e., lag period 0-24 h) was associated with significantly higher odds of atrial fibrillation (1.7%-3.4%), atrial flutter (8.1%-11.4%) and supraventricular tachycardia (3.4%-8.9%). Exposure to PM2.5-10 was associated with significantly higher odds of atrial flutter (8.7%) and supraventricular tachycardia (5.4%), and exposure to ozone was associated with higher odds of supraventricular tachycardia (3.4%). The exposure-response relationships were approximately linear, without discernible concentration thresholds. INTERPRETATION: Exposure to air pollution was associated with the onset of symptomatic arrhythmia shortly after exposure. This finding highlights the importance of further reducing air pollution and taking prompt protective measures for susceptible populations during periods of elevated levels of air pollutants.

A risk score to predict postdischarge bleeding among acute coronary syndrome patients undergoing percutaneous coronary intervention: BRIC-ACS study.

BACKGROUND: Dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI) prevents ischemic events while increasing bleeding risk. Real-world-based metrics to accurately predict postdischarge bleeding (PDB) occurrence and its potential impact on postdischarge major cardiovascular event (MACE) remain undefined. This study sought to evaluate the impact of PDB on MACE occurrence, and to develop a score to predict PDB risk among Chinese acute coronary syndrome (ACS) patients after PCI. METHODS AND RESULTS: From May 2014 to January 2016, 2496 ACS patients who underwent PCI were recruited consecutively from 29 nationally representative Chinese tertiary hospitals. Among 2,381 patients (95.4%, 2,381/2,496) who completed 1-year follow-up, the cumulative incidence of PDB (bleeding academic research consortium type [BARC] ≥2) and postdischarge MACE (a composite of all-cause death, nonfatal myocardial infarction, ischemic stroke, or urgent revascularization) was 4.9% (n = 117) and 3.3% (n = 79), respectively. The association between PDB and MACE during 1-year follow-up, as well as the impact of DAPT with ticagrelor or clopidogrel on PDB were evaluated. PDB was associated with higher risk of postdischarge MACE (7.7 vs. 3.1%; adjusted hazard ratio: 2.59 [95% confidence interval: 1.17-5.74]; p = .02). For ticagrelor versus clopidogrel, PDB risk was higher (8.0 vs. 4.4%; 2.05 [1.17-3.60]; p = .01), while MACE risk was similar (2.0 vs. 3.4%; 0.70 [0.25-1.93]; p = .49). Based on identified PDB predictors, the constructed bleeding risk in real world Chinese acute coronary syndrome patients (BRIC-ACS) score for PDB was established. C-statistic for the score for PDB was 0.67 (95% CI: 0.62-0.73) in the overall cohort, and >0.70 in subgroups with non-ST- and ST-segment elevation myocardial infarction, diabetes and receiving more than two drug eluting stents. CONCLUSIONS: In Chinese ACS patients, PDB with BARC ≥2 was associated with higher risk for MACE after PCI. The constructed BRIC-ACS risk score provides a useful tool for PDB discrimination, particularly among high ischemic and bleeding risk patients.

Coordinated Digital-Assisted Program Improved Door-to-Balloon Time for Acute Chest Pain Patients.

Emergency care for patients with chest pain can be a challenge in remote areas. Digital communication technology has the potential to improve outcomes by allowing early diagnosis and faster treatment. The aim of the present study was to investigate whether implementation of a coordinated digital-assisted program (CDAP) for Chinese hospitals can reduce the door-to-balloon (D2B) time for percutaneous coronary intervention (PCI) in acute chest pain patients in China. From March to December 2011, 609 patients (CDAP group) requiring an emergency response for acute chest pain were evaluated using this CDAP. The results were compared in terms of time interval reduction (including D2B) and economic indices with those of 528 patients (non-CDAP group) previously treated by conventional protocols after admission. We screened 154 and 127 eligible patients under PCI in the CDAP and non-CDAP groups, respectively. PCI patients achieved a D2B time < 90 minutes using CDAP (82.5 versus 26.0%, P < 0.001). CDAP reduced D2B time under PCI and reduced hospitalization lengths and costs (all P < 0.001).

Activation of κ-opioid receptor by U50,488H improves vascular dysfunction in streptozotocin-induced diabetic rats.

BACKGROUND: Evidence suggests that activation of κ-opioid receptor (KOR) by U50,488H exhibits potential cardiovascular protective properties. However, the effects of U50,488H on vascular dysfunction in diabetes mellitus (DM) are still not clear. The present study was designed to investigate the effects of U50,488H on vascular dysfunction in diabetic rats and explore the underlying mechanisms involved. METHODS: Rats were randomly divided into control, DM, DM + vehicle, DM + U50,488H and DM + nor-binaltorphimine (nor-BNI) groups. Streptozotocin injection was used to induce DM. Weight, blood glucose, blood pressure and plasma insulin for each group were measured. Arterial functions were assessed with isolated vessels mounted for isometric tension recordings. Angiotensin II (ANG II), soluble intercellular adhesion molecule-1 (sICAM-1), interleukin (IL)-6 and IL-8 levels were measured by ELISA, and endothelial nitric oxide synthase (eNOS) phosphorylation and NF-κB p65 translocation were measured by Western blot. RESULTS: Activation of KOR by U50,488H reduced the enhanced contractility of aortas to KCl and noradrenaline and increased acetylcholine-induced vascular relaxation, which could also protect the aortal ultrastructure in DM. U50,488H treatment resulted in reduction in ANG II, sICAM-1, IL-6 and IL-8 levels and elevation in NO levels, while these effects were abolished by nor-BNI treatment. Further more, eNOS phosphorylation was increased, and NF-κB p65 translocation was decreased after U50,488H treatment. CONCLUSIONS: Our study demonstrated that U50,488H may have therapeutic effects on diabetic vascular dysfunction by improving endothelial dysfunction and attenuating chronic inflammation, which may be dependent on phosphorylation of eNOS and downstream inhibition of NF-кB.

[Association between body mass index and cardiovascular events in male elderly hypertensive patients].

OBJECTIVE: To observe the long-term relationship between body mass index (BMI) and cardiovascular events in male elderly hypertensive patients. METHODS: A total of 839 male elderly (>65 years old) hypertensive patients were included in this prospective study. Baseline data were obtained on January 2004 and participants were followed up yearly till January 2014. Patients were divided into 3 groups according to their BMI: normal weight group (18.5 kg/m² ≤ BMI<24.0 kg/²), overweight group (24.0 kg/m² ≤ BMI<28.0 kg/m²), obese group (BMI ≥ 28.0 kg/m²). All-cause death and cardiovascular events were compared. RESULTS: The average age of all 839 hypertension men was (75.4 ± 4.8) years at baseline. Baseline systolic blood pressure was (133.7 ± 14.6) mmHg (1 mmHg=0.133 kPa), diastolic blood pressure was (74.3 ± 9.3)mmHg. Baseline systolic and diastolic blood pressure was similar among the three groups. All 839 patients completed follow-up. There were 178 all-cause deaths, 54 cardiovascular deaths, 51 new/recurrent myocardial infarctions and 105 new/recurrent strokes during follow up. Incidence of all-cause mortality in overweight group (16.74%,72/430) was significantly lower than in normal weight group (27.01% (74/274), P<0.05). Kaplan-Meier curves showed the all-cause mortality and cardiovascular mortality were higher in normal weight group than in the other two groups. According to the Cox proportional hazards regression model, the risk of all-cause mortality (RR=0.867, 95% CI: 0.792-0.949) and cardiovascular death (RR=0.179, 95% CI : 0.05-0.645) in patients with a BMI ≥ 24.0 kg/m² were lower than in the group with BMI<24.0 kg/m². CONCLUSION: Obesity paradox phenomenon is observed in elderly male hypertensive patients in that higher BMI is associated with lower mortality risks in elderly male hypertensive patients during the 10 years follow-up.

Polymorphism of stromal cell-derived factor-1 selectively upregulates gene expression and is associated with increased susceptibility to coronary artery disease.

Stromal cell-derived factor-1 (SDF-1) plays critical roles in vascular development and hematopoiesis. Here, we investigated the function of SDF-1 rs1801157G/A polymorphism in various immune cells and examined its association with susceptibility to coronary artery disease (CAD). Protein and mRNA levels of SDF-1 were tested in peripheral CD4+ T cell, CD8+ T cells, monocytes, and natural killer (NK) T cells from healthy donors with different genotypes of rs1801157G/A polymorphism. Prevalence of the polymorphism was compared between CAD patients and healthy controls. Data revealed that SDF-1 mRNA and protein were detectable in CD4+ T cells, CD8+ T cells, monocytes and NK T cells. Interestingly, both protein level and mRNA level of SDF-1 were significantly increased in the monocytes with rs1801157AA genotype, whereas the same phenomenon was not observed in the other three cell types. Blockage of CD14 completely inhibited the upregulation of SDF-1 in the monocytes with rs1801157AA genotype. Association analysis showed that frequencies of the rs1801157AA genotype and A allele were significantly higher in CAD cases than in controls (odds ratio [OR]=2.28, 95% confidence interval [CI], 1.50-3.29, p<0.0001, and OR=1.46, 95% CI, 1.21-3.73, p<0.0001, respectively). Also, prevalence of rs1801157AA genotype was further increased in cases with ST-elevation myocardial infarction (OR=1.65, 95% CI, 1.04-2.56, p=0.028). Our data suggest a novel pathway for regulating SDF-1 and a new risk factor for CAD.

[Impact of establishing regional collaborative network on reperfusion time and prognosis of patients with ST-segment elevated myocardial infarction admitting to community hospitals without percutaneous coronary intervention capacity].

OBJECTIVE: To investigate the impact of establishing regional collaborative network on reperfusion time and prognosis of patients with ST-segment elevated myocardial infarction (STEMI) admitting to community hospitals without percutaneous coronary intervention (PCI) capacity (Non-PCI hospital). METHODS: A regional collaborative network was developed, consisting of a PCI center and over 30 Non-PCI hospitals and connected by a tele-transmitted real-time 12-lead electrocardiogram system. This system enables the cardiologists on duty in PCI center to help the physicians in the Non-PCI hospitals (network hospital) to confirm the diagnosis and choose a reperfusion strategy for STEMI patients. All cardiologists in PCI center and physicians in Non-PCI hospitals were trained to follow the flowchart of reperfusion strategies for STEMI patients to shorten the reperfusion time. The mean time from door of Non-PCI hospital to needle of thrombolysis (D-to-N), the mean time from door of PCI center to balloon (D-to-B) and the mean time from the first medical contact to balloon (FMC-to-B) and the 1-year mortality were compared between the 20 months before and the 20 months after establishment of the regional collaborative network for patients with the first medical contact in three network hospitals. RESULTS: After establishment of the regional collaborative network, the mean D-to-N time was significantly shortened from (71 ± 62) min to (28 ± 9) min (P < 0.05), the rate of D-to-N below 30 min was increased from 11% (2/18) to 74% (26/35); the mean FMC-to-B and the mean D-to-B time were remarkably reduced in both complementary percutaneous coronary intervention and transfer percutaneous coronary intervention patients (all P < 0.05), the 1-year mortality post reperfusion was reduced from 15.1% (8/53) to 7.0% (10/142) (P < 0.05). CONCLUSION: The establishment of regional collaborative network could shorten the perfusion time and reduce the 1-year mortality for STEMI patients presenting to Non-PCI hospitals.

Research on entity relation extraction for Chinese medical text.

Currently, the primary challenges in entity relation extraction are the existence of overlapping relations and cascading errors. In addressing these issues, both CasRel and TPLinker have demonstrated their competitiveness. This study aims to explore the application of these two models in the context of entity relation extraction from Chinese medical text. We evaluate the performance of these models using the publicly available dataset CMeIE and further enhance their capabilities through the incorporation of pre-trained models that are tailored to the specific characteristics of the text. The experimental findings demonstrate that the TPLinker model exhibits a heightened and consistent boosting effect compared to CasRel, while also attaining superior performance through the utilization of advanced pre-trained models. Notably, the MacBERT + TPLinker combination emerges as the optimal choice, surpassing the benchmark model by 12.45% and outperforming the leading model ERNIE-Health 3.0 in the CBLUE challenge by 2.31%.

Regional variations in management and outcomes of patients with acute coronary syndrome in China: Evidence from the National Chest Pain Center Program.

Regional variations in acute coronary syndrome (ACS) management and outcomes have been an enormous public health issue. However, studies have yet to explore how to reduce the variations. The National Chest Pain Center Program (NCPCP) is the first nationwide, hospital-based, comprehensive, continuous quality improvement program for improving the quality of care in patients with ACS in China. We evaluated the association of NCPCP and regional variations in ACS healthcare using generalized linear mixed models and interaction analysis. Patients in the Western region had longer onset-to-first medical contact (FMC) time and time stay in non-percutaneous coronary intervention (PCI) hospitals, lower rates of PCI for ST-elevation myocardial infarction (STEMI) patients, and higher rates of medication usage. Patients in Central regions had relatively lower in-hospital mortality and in-hospital heart failure rates. Differences in the door-to-balloon time (DtoB) and in-hospital mortality between Western and Eastern regions were less after accreditation (ß = -8.82, 95% confidence interval (CI) -14.61 to -3.03; OR = 0.79, 95%CI 0.70 to 0.91). Similar results were found in differences in DtoB time, primary PCI rate for STEMI between Central and Eastern regions. The differences in PCI for higher-risk non-ST-segment elevation acute coronary syndrome (NSTE-ACS) patients among different regions had been smaller. Additionally, the differences in medication use between Eastern and Western regions were higher after accreditation. Regional variations remained high in this large cohort of patients with ACS from hospitals participating in the NCPCP in China. More comprehensive interventions and hospital internal system optimizations are needed to further reduce regional variations in the management and outcomes of patients with ACS.

Chinese Society of Cardiology guidelines on the diagnosis and treatment of adult fulminant myocarditis.

Fulminant myocarditis is an acute diffuse inflammatory disease of myocardium. It is characterized by acute onset, rapid progress and high risk of death. Its pathogenesis involves excessive immune activation of the innate immune system and formation of inflammatory storm. According to China's practical experience, the adoption of the "life support-based comprehensive treatment regimen" (with mechanical circulation support and immunomodulation therapy as the core) can significantly improve the survival rate and long-term prognosis. Special emphasis is placed on very early identification,very early diagnosis,very early prediction and very early treatment.

[Impacts of establishment of chest pain center on the door-to-balloon time and the short-term outcome after primary percutaneous coronary intervention of patients with ST segment elevated myocardial infarction].

OBJECTIVE: To investigate the impact of the establishment of chest pain center (CPC) model based on the pre-hospital real-time tele-12-lead electrocardiogram on the door-to-balloon (D-to-B) time and short-term outcome after primary percutaneous coronary intervention (PPCI) of patients with ST-segment elevated myocardial infarction (STEMI). METHODS: A regular CPC was established with pre-hospital transmitted real-time 12-lead electrocardiogram system for pre-hospital diagnosis of STEMI and enabled the STEMI patients to bypass the emergency room and directly treated in the catheter lab to shorten the D-to-B time. The mean D-to-B time, the short-term outcome and medical costs were compared in PPCI patients before (93 cases, group A) and after (149 cases, group B) the establishment of CPC. RESULTS: After the establishment of CPC, the annual mean D-to-B time was significantly shortened [(127 ± 79) min in group A vs.(72 ± 23 )min in group B, P < 0.01], the shortest monthly mean D-to-B time was remarkably reduced in group B than in group A [(56 ± 11) min vs. (73 ± 14) min, P < 0.01]. The annual ratio of D-to-B below 90 minutes was significantly increased from 62.4% (58/93) in group A to 91.9% (137/149) in group B (P < 0.05) . The in-hospital mortality rate tended to be lower and the incidence of heart failure during hospitalization was significantly reduced in group B compared with group A [3.4% (5/149) vs. 6.5% (6/93), P > 0.05; 14.1% (21/149) vs. 24.7% (23/93), P < 0.05]. The length of hospital stay was slightly shortened from (8.98 ± 4.89) days to (7.79 ± 5.43) days (P > 0.05). Corrected mean medical cost went down by 9.4% (P < 0.05). CONCLUSION: The establishment of CPC may significantly shorten the D-to-B time, improve the short-term outcome and reduce the hospitalization cost for PPCI patients with STEMI.

[The detection of non-stationary T-wave alternans: a modified correlation method].

T-wave alternans (TWA) refers to a phenomenon appearing in the surface electrocardiograph (ECG) as a consistent fluctuation in morphology and amplitude of the T wave on an "every-other-beat" basis. Correlation method (CM) has a certain ability to detect the non-stationary TWA, but it is very sensitive to noise. In this paper we propose a modified correlation method to ensure a stable and accurate detection of non-stationary TWA. Compared to the CM, the method modifies the judge condition and uses the linear fitting to limit the noise to gain the ability of detecting of non-stationary TWA. Our simulation and clinical data assessment study demonstrates the improved performance of the proposed algorithm.

Silencing hsa_circ_0049271 attenuates hypoxia-reoxygenation (H/R)-induced myocardial cell injury via the miR-17-3p/FZD4 signaling axis.

Background: This study sought to explore the role and molecular mechanism of circ_0049271 in hypoxia-reoxygenation (H/R)-induced cardiomyocyte injury. Methods: Significantly upregulated circular ribonucleic acids (circRNAs) in Gene Expression Omnibus (GEO) data sets were identified using a Venn diagram. A H9c2 (rat cardiomyocytes) cell model of acute myocardial infarction (AMI) was induced by 1% H/R. Quantitative reverse transcription-polymerase chain reaction was used to detect the expression levels of circ_0049271, miR-17-3p, and FZD4 in clinical blood samples and cells, and Cell Counting Kit-8 (CCK-8) was used to determine the proliferation rate of the cells in each group. Next, flow cytometry and Western blot were used to evaluate cell apoptosis. Biochemical tests and enzyme-linked immunosorbent assays (ELISAs) were then used to determine the activities/levels of the cell damage markers [i.e., creatine kinase (CK) and lactate dehydrogenase (LDH)], oxidative stress substances [i.e., malondialdehyde (MDA), reactive oxygen species (ROS), and superoxide dismutase (SOD)], and inflammatory factors [i.e., interleukin (IL)-1ß, IL-6, and IL-8]. In addition, intermolecular interactions were verified using dual-luciferase reporter and RNA pull-down experiments. Results: Circ_0049271 was significantly upregulated in both the blood of the AMI patients and the H/R-induced H9c2 cells. The knockdown of circ_0049271 increased the cell proliferation rate, decreased the apoptosis rate, inhibited oxidative stress (ROS and MDA were upregulated, and SOD was downregulated) and inflammatory responses (IL-1, IL-6, and IL-8 were downregulated), and relieved cell damage. However, the overexpression of circ_0049271 promoted H/R-induced H9c2 cell damage. Further experiments showed that miR-17-3p was a target of circ_0049271, and miR-17-3p was negatively correlated with circ_0049271 in the AMI blood samples. Additionally, miR-17-3p was found to target FZD4. A further exploration also revealed that miR-17-3p knockdown or FZD4 overexpression reversed the effects of si-circ_0049271 on the H/R-induced H9c2 cells; that is, miR-17-3p knockdown or FZD4 overexpression promoted H/R-induced injury in the H9c2 cells. Conclusions: Circ_0049271 promoted cellular function damage (e.g., proliferation inhibition, apoptosis, oxidative stress, and inflammation) in H/R-induced H9c2 cardiomyocytes via the miR-17-3p/FZD4 signaling axis.

Cold Spells and the Onset of Acute Myocardial Infarction: A Nationwide Case-Crossover Study in 323 Chinese Cities.

BACKGROUND: Few studies have explored the relationships between cold spells and acute myocardial infarction (AMI) using the information of symptom onset. OBJECTIVES: We assessed the impact of cold spells on AMI onset and the potential effect modifiers. METHODS: We conducted a time-stratified case-crossover study among 456,051 eligible patients with AMI from 2,054 hospitals in 323 Chinese cities between January 2015 and June 2021 during cold seasons (November to March). Nine definitions of cold spells were used by combining three relative temperature thresholds (i.e., lower than the 7.5th, 5th, and 2.5th percentiles) and three durations of at least 2-4 consecutive d. Conditional logistic regressions with distributed lag models were applied to evaluate the cumulated effects of cold spells on AMI onset over lags 0-6 d, after adjusting for daily mean temperature. RESULTS: The associations generally appeared on lag 1 d, peaked on lag 3 d, and became nonsignificant approximately on lag 5 d. Cold spells defined by more stringent thresholds of temperature were associated with higher risks of AMI onset. For cold spell days defined by a daily mean temperature of ≤7.5th percentile and durations of ≥2d, ≥3d, and ≥4d, the percentage changes in AMI risk were 4.24% [95% confidence interval (CI): 2.31%, 6.20%], 3.48% (95% CI: 1.62%, 5.38%), and 2.82% (95% CI: 0.98%, 4.70%), respectively. Significant AMI risks associated with cold spells were observed among cases from regions without centralized heating, whereas null or much weaker risks were found among those from regions with centralized heating. Patients ≥65 years of age were more susceptible to cold spells. DISCUSSION: This national case-crossover study presents compelling evidence that cold spells could significantly increase the risk of AMI onset. https://doi.org/10.1289/EHP11841.

Exercise training combined with alprostadil improves myocardial infarction and coronary microcirculation disorder in aged rats by inhibiting mitogen-activated protein kinase (MAPK) signaling pathway activation.

Background: We aimed to explore the effects and mechanisms of exercise training combined with alprostadil (ALPR) treatment on myocardial infarction (MI) in aged rats. Methods: Male Wistar rats were randomly divided into five groups. One day after MI induction, an automatic biochemical analyzer was used to measure cardiac troponin I (cTnI), cardiac troponin T (cTnT), and creatine kinase MB isoenzyme (CK-MB) serum levels. One week after MI induction, echocardiography was performed to examine the left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD), left ventricular ejection fraction (LVEF), and left ventricular fraction shortening (LVFS) rates of the rats. Parameters such as body weight (BW), heart mass index, and the heart weight (HW)/tibia length (TL) ratio of the rats were also calculated. Western blot was performed to assess angiogenesis and mitogen-activated protein kinase (MAPK) signal-related protein expression. Results: Compared with the MI group, the LVEDD and LVESD in the Trained + ALPR group were significantly decreased, while LVEF, LVFS, HW/BW, and HW/TL were significantly increased. Additionally, the Trained + ALPR group exhibited decreased levels of cTnI, cTnT, and CK-MB and significantly reduced MI size and myocardial injury. Moreover, compared with the Trained or ALPR group, the Trained + ALPR group showed upregulated energy metabolism, increased microvessel density, and better efficacy. Finally, the Trained + ALPR group showed a significant increase in angiogenesis-related proteins and a significant reduction in MAPK signaling pathway-related protein activity. Conclusions: Exercise training combined with ALPR improved MI in elderly rats by inhibiting MAPK signaling, promoting angiogenesis, and increasing metabolism.

Case Fatality Rate of Patients with Acute Myocardial Infarction in 253 Chest Pain Centers - China, 2019-2020.

What is already known about this topic?: Acute myocardial infarction (AMI) is the most serious form of cardiovascular diseases. The case fatality rate (CFR) of AMI patients is an important index to reflect the prognosis of AMI. What is added by this report?: During the study period, the overall 30-day, 60-day, and 90-day CFR of AMI was 5.9%, 6.9%, and 7.6%, respectively. The CFRs in grade Ⅲ hospitals were lower than in grade Ⅱ hospitals, and the in-hospital CFR was significantly lower than that in post-discharge out-of-hospital. What are the implications for public health practice?: This study can provide evidence for targeted prevention and highlight the need to strengthen the level of treatment of patients with AMI in grade Ⅱ hospitals.

Low ambient temperature might trigger the symptom onset of pulmonary embolism: A nationwide case-crossover study at hourly level in China.

BACKGROUND: Pulmonary embolism (PE) is an important cause of death and its seasonality has long been observed. Very few epidemiological studies have explored the potential role of ambient temperature in PE symptom onset, especially at the hourly level. METHODS: We conducted a time-stratified case-crossover study among 17,903 PE patients with hourly onset of symptom from 1590 hospitals across China between January 2015 and September 2020. Conditional logistic regression model combined with distributed lag non-linear models were used to explore the associations between hourly ambient temperature and PE symptom onset. The attributable fractions due to non-optimum temperature were calculated. RESULTS: The exposure-response relationship curve was inverse and almost linear. Lower temperature was significantly associated with higher risk of PE symptom onset when temperature was below 18 °C. This risk occurred immediately at the same hour, attenuated thereafter, and became nonsignificant at approximately 72 h after exposure. Compared with the referent temperature (P99, 34.1 °C), the odds ratio of PE symptom onset associated with extremely low temperature (P1, -16.1 °C) over lag 0-72 h was 1.63 (95%CI: 1.23, 2.16). Low temperature may account for 16.19 % of the symptom onset nationally with higher proportion in the south of China. The effects were stronger in older adults, males, and cold seasons. CONCLUSIONS: We provided the first-hand robust evidence that transient exposure (at the hourly level) to low temperature might trigger the symptom onset of PE and constitute a considerable burden for PE patients. Targeted protections and health education are needed for susceptible populations.

Twin peaks of in-hospital mortality among patients with STEMI across five phases of COVID-19 outbreak in China: a nation-wide study.

Lockdown and re-opening may become cyclical due to the recurrent waves of the COVID-19 epidemic. Few studies have examined temporal trends and determinants of in-hospital mortality among patients with ST-segment elevation myocardial infarction (STEMI), a life-threatening condition that requires emergency medical care. Using nation-wide data before, during and after the Wuhan lockdown, we aimed to depict temporal patterns and major determinants of STEMI in-hospital mortality in China across five time periods of the COVID-19 epidemic. We analyzed the data of 283,661 STEMI patients who were admitted to 4,487 chest-pain-centers across China, from January 1, 2019 to May 31, 2020. Compared with the period before the lockdown, STEMI in-hospital mortality increased by 25% (OR 1.25, 95%CI 1.16-1.34) during Early Lockdown, by 12% (OR 1.12, 95%CI 1.03-1.22) during Later Lockdown, by 35% (OR 1.35, 95%CI 1.21-1.50) during Early Lift, and returned to pre-COVID risk (OR 1.04, 95%CI 0.95-1.14) during Later Lift. For each time-period, we observed a clear mortality gradient by timing and types of revascularization procedure. In conclusion, the COVID-19 epidemic had a significant adverse impact on STEMI in-hospital mortality, with bimodal peaks during early lockdown and early lift periods and clear mortality gradients by timing and types of revascularization procedure, independent of the time periods.

Non-optimum temperature increases risk and burden of acute myocardial infarction onset: A nationwide case-crossover study at hourly level in 324 Chinese cities.

Background: The associations of ambient temperature with acute myocardial infarction (AMI) have seldom been examined based on the time of symptom onset. Methods: We conducted a time-stratified case-crossover study among 1,046,773 eligible AMI patients from 2,093 hospitals in 324 Chinese cities from January 1, 2015 to June 30, 2021, after excluding those transferred from other hospitals or having not reported the time of symptom onset. Hourly exposure to ambient temperature was calculated as multiple moving 24-h averages (days) before hourly onset of AMI symptoms. Conditional logistic regression and distributed lag non-linear models with a duration of 0-21 days were used to estimate the cumulative associations of non-optimum temperature with AMI onset and the corresponding disease burden nationally. Subgroup analyses by region and period were conducted. Specifically, cities with and without centralized heating system were classified into heating and non-heating regions, respectively. The whole year in heating region was divided into heating and non-heating periods based on the duration of centralized heating in each city. Findings: Almost monotonically increasing risks were observed for both overall AMI and its two subtypes when ambient temperature declined. The effects of extremely low temperature occurred immediately on the concurrent day, and lasted up to almost 3 weeks. The excess risks of AMI onset associated with non-optimum ambient temperatures were observed during the whole year in the non-heating region and non-heating period in the heating region, but not during heating period. Specifically, odds ratios of AMI onset associated with extremely low temperature cumulated over 0-21 days were 1.24 (95% CI: 1.13-1.37), 1.46 (95% CI: 1.20-1.76), and 1.62 (95% CI: 1.46-1.81) in the heating region during non-heating period, in the non-heating region during winter and non-winter period, respectively. The heat effects on AMI onset were very modest and transient. Totally, 13.26% of AMI cases could be attributable to non-optimum temperatures nationally. The burden of AMI attributable to non-optimum temperature was much smaller in heating region than in non-heating region. Somewhat stronger effects were observed in females and patients aged older than 65. Interpretation: This nationwide study provided robust evidence that non-optimum ambient temperature may significantly trigger AMI onset, and for the first time estimated the disease burden after accounting for spatial and seasonal heterogeneity. Centralized heating might substantially mitigate AMI burden due to non-optimum temperature. Funding: Shanghai International Science and Technology Partnership Project, National Natural Science Foundation of China, Talent Training Program of Zhongshan Hospital, Fudan University.