Prevalence, incidence and mortality of hypertrophic cardiomyopathy based on a population cohort of 21.9 million in China.

There are limited studies on the prevalence and incidence of clinically diagnosed hypertrophic myocardiopathy (HCM) and its mortality in the Chinese population, and the projected population burden of HCM over the next decades. We collected data on HCM and its mortality from the Beijing Municipal Health Commission Information Center (BMHCIC) database and estimated the prevalence and incidence based on the whole Beijing population. Calculation of population trends was performed using annual percentage change (APC) and average annual percentage change (AAPC). Finally, future HCM incidence was built by modelling projection of HCM to the next decades using Poisson regression analysis and Gray Model 1,1(GM [1,1]). The prevalence of HCM was 0.0069% (95%CI, 0.0065-0.0072%; N = 1343) in 2010, rising to 0.076% (95% CI, 0.074-0.077%; N = 16,616) in 2019, and the incidence of HCM was 6.85 per 100 000 person-year in 2010, rising to 11.76 per 100 000 person-year in 2019. Males had higher prevalence and incidence of HCM than females. The APPC for the rising incidence of HCM was 5.8% and the expected numbers will double increase in 2029 by assuming the same increase trend as the last decades. HCM had increased annual incidence of HF (APPC: 8.4, 4.4-12.6, p < 0.05), and relatively stable annual incidence of mortality (APPC: 1.2%, - 2.3% to 4.8%, p > 0.05) during the studied period. Males had lower mortality (2.70% vs. 4.20%, p < 0.001) than females. The calculated HCM prevalence was much lower compared to prior screening studies from 2004, although the predicted HCM incidence would double over the next decades. HCM was associated with a stable risk of mortality during the studied period.

Prevalence of recommended anticoagulation by guidelines preadmission and its impact on the incidence of acute myocardial infarction (AMI) and in-hospital outcomes after AMI in atrial fibrillation patients.

This study was designed to explore the prevalence of recommended anticoagulation by guidelines before admission and its impact on the incidence of acute myocardial infarction (AMI) and the AMI associated in-hospital outcomes in patients with atrial fibrillation (AF). 10,725 patients with AF at their first hospitalizations in our hospitals were retrospectively reviewed, with a prevalence of recommended anticoagulation preadmission 24.41% (Number = 2618). They had lower risk of AMI incidence (Adjusted OR 0.66, 95%CI 0.54-0.81, p < 0.001) compared to those without recommended anticoagulation after multivariate logistic regression. Furthermore, recommended anticoagulation preadmission reduced in-hospital all-cause death associated with AMI in univariate logistic analysis, but had no impact on the risk of in-hospital bleeding and stroke after AMI both in univariate and multivariate logistic analysis. The prevalence of recommended anticoagulation before admission was 24.41% in China. Recommended anticoagulation reduced incidence of hospitalized AMI, but had no impact on the associated in-hospital bleeding and stroke risk after AMI.

Prevalence and sex- and age-related risk of pulmonary embolism in in-hospital patients with atrial fibrillation: a multicenter retrospective study from China.

BACKGROUND: This study was designed to explore the prevalence of pulmonary embolism (PE) and sex and age-related risk of incident PE in in-hospital patients with atrial fibrillation (AF) in China. METHODS: A retrospective cohort of 15,688 AF patients (mean age: 72.56 years; 55.7% male) was identified from 2008 to 2018 in our hospitals. The prevalence and incidence of PE over a 2.28-year follow-up were studied. Unadjusted, age or sex-adjusted, and multivariate Cox regression were used to explore the risk of PE in the studied patients. RESULTS: One hundred eighty-two AF patients (1.2%) had PE at their first hospitalizations. Over a mean follow-up of 2.28 years, 85 patients developed PE, with an incidence of 0.24% per person-year. PE was more likely to occur in female and older patients with AF according to the unadjusted, age or sex-adjusted, and multivariate Cox regression analysis (all P<0.05). Moreover, a significant higher risk of PE was seen in female and older patients in AF using Kaplan-Meier analysis, respectively (log-rank: both P<0.001). CONCLUSIONS: In the current AF cohort, the prevalence of PE was 1.2% and the incidence of PE was 0.24% per person-year during a mean follow-up of 2.28 years. Female and older patients were more likely to experience PE compared to male and younger patients.

Differences of Matrix Metalloproteinase 2 Expression between Left and Right Ventricles in Response to Nandrolone Decanoate and/or Swimming Training in Mice.

BACKGROUND: Matrix metalloproteinase (MMP)-2 plays an important role in the remodeling of left ventricles (LVs) and right ventricles (RVs). We investigated the differences of MMP-2 expression between LV and RV in response to nandrolone decanoate (ND), swimming training (ST), and combined ND and ST (NS) in mice, based on their structural, functional, and biochemical characteristics. METHODS: Totally 28 male C57B1 mice (6 weeks old; 20-23 g) were divided into four groups, including the control (n = 7), ND (n = 6), ST (n = 8), and NS (n = 7) groups. After respective treatments for 8 weeks, echocardiographic examination was used to assess the cardiac structure and function. Van Gieson stain was used to examine the fibrosis of LV and RV in response to different treatments, and Western blotting analysis was performed to explore different MMP-2 expressions between LV and RV in response to ND and/or ST. Analysis of variance was used for comparing the four groups. RESULTS: At 8 weeks, right ventricular dimension/body weight in the ND group was larger than the other three groups (F = 7.12, P < 0.05) according to the echocardiographic examination. Fibrosis induced by ND administration was increased more in RV (2.59%) than that in LV (2.21%). MMP-2 expression of the ND group in RV was significantly greater than the control and NS groups in RV and the corresponding ND group in LV. CONCLUSION: The experimental data support the hypothesis that ND administration induces greater MMP-2 expression increase in RV compared to LV, leading to consequent RV dilation.

Meta-Analysis of Effectiveness and Safety of Oral Anticoagulants in Atrial Fibrillation With Focus on Apixaban.

We performed a meta-analysis of data on the effectiveness and safety of apixaban compared with other oral anticoagulants (warfarin or rivaroxaban or dabigatran or edoxaban) for stroke prevention in atrial fibrillation (AF) in different settings of randomized controlled trials, real-world studies, and radiofrequency ablation (RFA). Thirty studies were searched in PubMed, the Cochrane Library, and Clinicaltrials.gov databases reporting comparative effectiveness and safety of apixaban with warfarin (n = 23), rivaroxaban (n = 12), dabigatran (n = 13), or edoxaban (n = 2) for stroke prevention in AF. In real-world estimates, apixaban was similar to warfarin for the prevention of stroke or systematic thromboembolism (hazard ratio 0.93, 95% CI 0.71 to 1.14, I2 = 82.9%, N = 7), and safer than warfarin in the risks of major bleeding (hazard ratio 0.62, 95% CI 0.54 to 0.70, I2 = 18.7%, N = 9) in patients with AF. The risk of stroke or thromboembolism with apixaban was similar to rivaroxaban, dabigatran, and edoxaban in the settings of real-world studies and RFA. Major bleeding with apixaban was generally lower than rivaroxaban (relative risks 0.45, 95% CI 0.38 to 0.53, I2 = 0%, N = 5) and similar to dabigatran in real-world studies (relative risks 1.44, 95% CI 0.33 to 6.30, I2 = 97.7%, N = 5), but similar to rivaroxaban, dabigatran, and edoxaban in RFA. In conclusion, our meta-analysis provides a comprehensive estimate of the effectiveness and safety of apixaban compared with other oral anticoagulants (warfarin, rivaroxaban, dabigatran, and edoxaban) in patients with AF in different settings of randomized controlled trial, real-world studies, and RFA.

Safety of antithrombotic drugs in patients with atrial fibrillation and non-end-stage chronic kidney disease: Meta-analysis and systematic review.

OBJECTIVE: To evaluate the safety of antithrombotic drugs used in patients with both atrial fibrillation (AF) and non-end-stage chronic kidney disease (NECKD). METHODS: A search was performed for studies on major bleeding outcomes in patients with concurrent AF and NECKD using Medline and Cochrane databases on 19th February, 2015. Fixed- or random-effects meta-analysis was adopted for evaluating pooled effect sizes according to whether heterogeneity existed. RESULTS: Twelve articles were included for analysis. Three studies evaluated AF patients who took warfarin vs. placebo/antiplatelet drugs in the presence of NECKD. No significant difference in major bleeding risk was observed according to the pooled analysis using the random-effects model (RR: 1.05, 95% CI: 0.74-1.36). The risk of a composite of major bleeding outcomes was reduced by 19% in patients randomized to direct oral anticoagulants (DOACs) compared to dose-adjusted warfarin from pooled data of three randomized controlled trials with regard to AF and NECKD (RR: 0.81, 95% CI: 0.75-0.88). This superiority of DOACs to warfarin maintained until the renal function was severely impaired. CONCLUSIONS: In patients with AF and NECKD, no significant increase in the incidence of major bleeding outcomes was observed in warfarin use compared with placebo/antiplatelet drugs. DOACs reduced the risk of major bleeding by 19% compared to warfarin and further data-exploration indicated that the risk did not increase as renal function deteriorated during the renal status of mild to moderate impairment.

Differences in Quality of Life Between Atrial Fibrillation Patients with Low Stroke Risk Treated With and Without Catheter Ablation.

BACKGROUND: Impacts of a single radiofrequency ablation (RFA) on quality of life (QoL) were not well investigated in atrial fibrillation (AF) patients with low stroke risk. METHODS AND RESULTS: Nine hundred AF patients with low CHADS2 score (ie, CHADS2 ≤1) who completed both a baseline and 6-month Atrial Fibrillation Effect on QualiTy-of-life (AFEQT) questionnaire were selected from The Chinese Atrial Fibrillation Registry between 2011 and 2013. A final cohort of 222 patients was constructed after a propensity score matching with 74 in the RFA group and 148 in the non-RFA group. Domains of AFEQT were balanced at baseline between the 2 groups. No statistically significant differences were noted in QoL (all P>0.05) when AFEQT at 6 months was compared between groups, except for the symptoms domain (83.07±12.37 units in the RFA group vs. 77.68±17.14 units in the non-RFA group; P=0.008) and treatment satisfaction domain (76.34±14.92 units in the RFA group vs. 70.38±16.81 units in the non-RFA group; P=0.01). Within-group changes in all domains and the global score of the questionnaire were moderate to large, whereas between-group comparisons in baseline to 6-month changes and QoL at 6 months were small to moderate according to Cohen effect sizes. CONCLUSIONS: QoL was balanced at baseline and improved at 6 months in both groups from this observational propensity-matched cohort based on the AFEQT questionnaire. However, RFA treatment was only associated with small-to-moderate superiorities over non-RFA treatment. The role of RFA in QoL improvement among AF patients with low stroke risk requires further research.

Effects of low molecular weight heparin on clot rate and activated clotting time: an in vitro study.

BACKGROUND: Due to lack of point-of-care testing, the use of low-molecular-weight heparin (LMWH) therapy in some special patients is restricted. This study was designed to explore the effects of LMWH on clot rate (CR) and activated clotting time (ACT), and to search for an appropriate method for bedside monitoring of anticoagulant activity of LMWH. METHODS: Thirty-two healthy volunteers were selected from the staff of Beijing Tongren Hospital. CR and ACT were measured with different reagents (glass beads, diatomite, kaolin and magnetic bar) on blood samples spiked with increasing concentrations of LMWH (dalteparin, 0.2-1.8 IU/ml). Correlations between concentrations of LMWH and values of CR and ACT were analysed based on the data obtained and regression analysis was performed to establish a regression equation. RESULTS: With the increase in doses of dalteparin, CR values reduced gradually. The values of CR of four reagents (glass beads, diatomite, kaolin and magnetic bar) were 20.4-4.5 IU/min, 27.4-6.9 IU/min, 27.5-7.9 IU/min and 7.8-0.1 IU/min respectively and an linear relationship was observed between the CR values and dalteparin concentrations (P < 0.05). The values of ACT were 173-615 seconds, 130-270 seconds, 123-226 seconds, 337-1411 seconds respectively, which showed a linear regression between the ACT values and dalteparin concentrations (P < 0.01). Differences in slope of the regression curves of ACT were observed with all the reagents tested (glass beads 248.2 s/IU, diatomite 74.8 s/IU, kaolin 58.2 s/IU and magnetic bar 1112.2 s/IU, P < 0.01). While the minimum concentration of dalteparin was 0.2 IU/ml, 0.4 IU/ml, 1.4 IU/ml and 0.2 IU/ml separately, the ACT values of the four coagulants (glass beads, diatomite, kaolin and magnetic bar) were beyond the normal limit and showed a noticeable increase respectively (P < 0.01). CONCLUSIONS: This study showed that there was an excellent linear relationship between the CR and ACT values and dalteparin concentrations for all the four reagents (glass beads, diatomite, kaolin and magnetic bar) in vitro. The sensitivity of different coagulation reagents to LMWH different. Choosing a suitable reagent, both CR and ACT were possible to be used as a convenient bedside test for LMWH.

[Sensitivity of new reagents for laboratory monitoring of low molecular weight heparin: an in vitro study].

OBJECTIVE: To explore the sensitivity of new activated clotting time (ACT) reagent for laboratory monitoring of low molecular weight heparin (LMWH). METHODS: Blood samples were collected from 30 healthy volunteers and different doses of LMWH (dalteparin) added. The dalteparin concentration of final blood samples was 0.1 - 1.8 U/ml. ACT and clot rate (CR) were measured with traditional reagent kaolin and new reagent magbar. Linear regression analysis was performed and a regression equation established between different dalteparin concentrations and their corresponding ACT and CR values. RESULTS: With rising dalteparin concentrations, the ACT values became gradually extended and the CR values were gradually reduced by both kaolin and magbar. Analysis of dose-response curves was obtained in vitro. And an excellent linear relationship was observed between the ACT and dalteparin concentrations for two reagents (P < 0.01). An exponential relationship was observed between the CR and dalteparin concentrations (P < 0.01). Differences in slope of regression curves of ACT were observed with the tested reagents (magbar 1097.6 s/U vs kaolin 59.3 s/U, P < 0.01). CONCLUSION: This in vitro study has shown that the sensitivity of new ACT test reagent (magbar) is good for laboratory monitoring of dalteparin. The new reagent magbar may be used for bedside monitoring of anticoagulant activity of LMWH.

[An angiographic trial to evaluate the efficacy and safety of tenecteplase in Chinese patients with acute myocardial infarction].

OBJECTIVE: In this randomized, open-label, multicenter, angiographic trial, we compared the efficacy and safety of tenecteplase (TNK-tPA) with alteplase (rt-PA) in Chinese patients with acute myocardial infarction. METHOD: Patients with acute ST-elevation myocardial infarction and pain to hospital time within 6 hours from October 2002, to March 2004 were randomly assigned a body weight-adjusted bolus of TNK-tPA (0.53 mg/kg over more than 10 s, n = 58) or front loaded rt-PA (< or = 100 mg, n = 52). Coronary angiography was performed at 90 min after initiating study drugs. All patients received aspirin and heparin (target activated partial thromboplastin time: 50-70 s). The primary end point of the trial was the rate of TIMI grade 3 flow at 90 minutes. Other end points included the rate of TIMI grade 2/3 flow at 90 minutes, all cause mortality at 30 days, the moderate/severe hemorrhage without intracranial hemorrhage (ICH) and ICH within 30 days. RESULTS: TIMI grade 3 flow at 90 minutes (68.4% vs. 66.7%, P = 1.00), TIMI grade 2 or 3 at 90 minutes (89.5% vs. 80.4%, P = 0.278), total mortality at 30 days (13.8% vs. 9.6%, P = 0.565), the rate of moderate/severe hemorrhage (8.6% vs. 5.8%, P = 0.72) and incidence of ICH (3.5% vs. 1.9%, P = 1.00) were all similar in TNK-tPA treated patients compared to rt-PA treated patients. CONCLUSION: The efficacy of single-bolus, weight-adjusted TNK-tPA fibrinolytic regimen is equivalent to front-loaded alteplase in terms of the rates of TIMI grade 3 flow, TIMI 2 or 3 flow. Incidences of moderate/severe hemorrhage, ICH and 30-days mortality were similar in TNK-tPA and rt-PA treated patients.

In vitro anticoagulation monitoring of low-molecular-weight heparin.

BACKGROUND: Although low-molecular-weight heparin has replaced unfractionated heparin to become the primary anticoagulation drug for treatment of acute coronary syndrome, there is no convenient bedside monitoring method. We explored the best laboratory monitoring method of low-molecular-weight heparins (enoxaparin, dalteparin, and nadroparin) by use of the Sonoclot coagulation analyzer to monitor the activated clotting time. METHODS: A total of 20 healthy volunteers were selected and 15 ml of fasting venous blood samples were collected and incubated. Four coagulants, kaolin, diatomite, glass bead, and magnetic stick, were used to determine the activated clotting time of the low-molecular-weight heparins at different in vitro anti-Xa factor concentrations. A correlation analysis was made to obtain the regression equation. The activated clotting time of the different low-molecular-weight heparins with the same anti-Xa factor concentration was monitored when the coagulant glass beads were applied. RESULTS: The activated clotting time measured using the glass beads, diatomite, kaolin, and magnetic stick showed a linear correlation with the concentration of nadroparin (r = 0.964, 0.966, 0.970, and 0.947, respectively). The regression equation showed that the linear slopes of different coagulants were significantly different (glass beads 230.03 s/IU, diatomite 89.91 s/IU, kaolin 50.87 s/IU, magnetic stick could not be calculated). When the concentration of the anti-Xa factor was the same for different low-molecular-weight heparins, the measured activated clotting time was different after the application of the glass bead coagulant. CONCLUSIONS: The glass bead coagulant is most feasible for monitoring the in vitro anticoagulation activity of nadroparin. The different effects of different low-molecular-weight heparins on the activated clotting time may be related to the different anti-IIa activities.

[Aspirin resistance in patients taking small dose of aspirin].

OBJECTIVE: To investigate the phenomenon and influencing factors of aspirin resistance (AR) in patients taking small dose of aspirin. METHODS: Three hundred and twenty-eight patients with stable cardiac and cerebral vascular diseases, diabetes mellitus, et al taking aspirin 100 mg/d for > or =14 days, and then their blood samples were collected for determination of optical platelet aggregation index using arachidonic acid (AA) and adenosine diphosphate (ADP). AR was defined as a state in which aggregation of > or =20% with AA and that > or =70% with ADP was found. Aspirin semi-resistance (ASR) was defined as meeting one of the above criteria. If both above criteria were not met, the condition was defined as aspirin sensitive. The difference in clinical characteristics among the groups and independent risk factors associated with AR and ASR were analyzed. RESULTS: Of 328 patients, 4.9% were AR, 27.4% were ASR. Among AR+ASR group, female, elderly, diabetic and hypertensive patients were predominant, but less common in smokers. Logistic regression analysis showed that diabetes mellitus was an independent risk factor of AR and ASR [odds ratio (OR)=0.953, 95% confidence interval (CI) 0.323-0.876, P=0.013], and hypertension was independently associated with AR and ASR (OR=0.610, 95%CI 0.376-0.991, P=0.046). The risk of AR and ASR was increased in non-smokers (OR=2.231, 95%CI 1.182-4.210, P=0.013). CONCLUSION: The incidence rate of AR in patients taking small dose of aspirin was 4.9%. Diabetes mellitus and hypertension are relative risk factors of AR and ASR. The risk of AR and ASR in the no-smoking patients is increased.

[The characteristics during exercise test in long QT syndrome patients and the effects of left cardiac sympathetic denervation].

OBJECTIVE: To explore the mechanism of the left cardiac sympathetic denervation (LCSD) surgery to reduce the incidence of cardiac events for long QT syndrome (LQTS) patients. METHODS: 12 LQTS patients were selected to do exercise test (ET) to mimic sympathetic activation. The dynamic alterations on ECG during exercise and recovery phases (Rec) were observed and the exercise test characteristics for LQTS patients before and after surgery were summarized and compared. RESULTS: The QTc at resting was shortened from 0.54 s +/- 0.04 s to 0.50 s +/- 0.04 s, P = 0.026, while the maximum heart rate during exercise decreased from 141 beat/min +/- 18 beat/min to 124 beat/min +/- 14 beat/min, P = 0.003. QTc was shortened during exercise, however, it was prolonged during the early recovery phase (before ET 0.54 s +/- 0.02 s, ET 10 min 0.46 s +/- 0.02 s, Rec 4 min 0.55 s +/- 0.03 s); LCSD could reduce such abrupt alteration of QTc during early recovery phase (after surgery: before ET 0.53 s +/- 0.03 s, ET 10 min 0.48 s +/- 0.03 s, Rec 4 min 0.53 s +/- 0.05 s). QT/RR interval slope, representing the adaptation response of QT interval to heart rate, became steeper after exercise (from 0.61 +/- 0.06 to 0.71 +/- 0.07 after exercise, P < 0.01). LCSD made the slopes become less steep both before exercise (from 0.61 +/- 0.06 before surgery to 0.55 +/- 0.07 after surgery, P = 0.013) and after exercise (from 0.71 +/- 0.07 before surgery to 0.66 +/- 0.06 after surgery, P = 0.018). Notched T wave alterations occurred in 7 patients at the end of exercise and/or during early recovery phase before surgery, and LCSD diminished such alteration in 4 patients. CONCLUSION: The slope between QT and RR both the pre-exercise and post-exercise slopes, interval becomes less steep after LCSD, which suggests that exaggerated delay in repolarization with decreasing heart rate for LQTS patients is improved by LCSD. This may be one of the mechanisms of LCSD efficacy for treating LQTS patients. Exercise test is one of tools to evaluate the effect of LCSD on LQTS patients.

[The effects of gender on heart rate adjustment of ST segment depression for identifying coronary arteriosclerosis disease].

OBJECTIVE: To assess the effects of gender on heart rate adjustment of ST segment depression (ST/HR) for identifying coronary arteriosclerotic disease. METHODS: One hundred and seventy three patients with suspected coronary disease (CAD) were referred for a routine treadmill exercise electrocardiogram and subsequently they underwent selective coronary angiography within 3 weeks. The magnitude of ST segment depression, ST/HR slope and calculated ST/HR index are performed by a computerized ECG system; exercise was performed according to the cornell protocol. CAD was defined by coronary angiography. We divided the patients into two groups by gender. RESULTS: Sensitivity and specificity for identifying CAD with ST/HR slope and ST/HR index were all significantly greater than that of standard electrocardiographic test criteria (P <0.05). Compared with standard criteria, the sensitivity for identifying CAD of ST/HR slope and ST/HR index increased 23% and 16% in men, 50% and 42% in women respectively; all difference were statistically significant (P <0.05). The specificity for identifying CAD with ST/HR slope and ST/HR index increased 58% and 50% in women, with no increase in men. CONCLUSIONS: It is suggested that sensitivity and specificity for identifying CAD with ST/HR slope and ST/HR index were all significantly higher than those with standard electrocardiographic test criteria in selected women patients. Sensitivity were significantly increased in selected men patients, with no significant change in specificity.