Assessing Risk in Patients with Stable Coronary Disease: When Should We Intensify Care and Follow-Up? Results from a Meta-Analysis of Observational Studies of the COURAGE and FAME Era

The clinical value of β-blockers in patients with stable angina

Stable angina, one manifestation of chronic coronary syndrome (CCS), is characterised by intermittent episodes of insufficient blood supply to the myocardium, provoking symptoms of myocardial ischaemia, particularly chest pain. These attacks usually occur during exercise or stress. Anti-ischaemic drugs are the mainstay of pharmacologic management of CCS with symptoms of angina. β-blockers reduce heart rate and myocardial contractility, thus reducing myocardial oxygen consumption. These drugs have been shown to ameliorate the frequency of anginal attacks and to improve exercise capacity in these patients. Current management guidelines include β-blockers as a first-line management option for most patients with CCS and symptoms of myocardial ischaemia, alongside dihydropyridine calcium channel blockers (CCB). The presence of comorbid angina and heart failure is a strong indication for starting with a β-blocker. β-blockers are also useful in the management of angina symptoms accompanied by a high heart rate, hypertension (with or without a renin-angiotensin-aldosterone-system [RAS] blocker or CCB), or microvascular angina (with a RAS blocker and a statin). A β-blocker is not suitable for a patient with low heart rate (<50 bpm), although use of a β-blocker may be supported by a pacemaker if the β-blocker is strongly indicated) and should be used at a low dose only in patients with low blood pressure.

Machine learning-based prediction of composite risk of cardiovascular events in patients with stable angina pectoris combined with coronary heart disease: development and validation of a clinical prediction model for Chinese patients

Objective: To develop a risk score model for the occurrence of composite cardiovascular events (CVE) in patients with stable angina pectoris (SA) combined with coronary heart disease (CHD) by comparing the modeling effects of various machine learning (ML) algorithms. Methods: In this prospective study, 690 patients with SA combined with CHD attending the Department of Integrative Cardiology, China-Japan Friendship Hospital, from October 2020 to October 2021 were included. The data set was randomly divided into a training group and a testing group in a 7:3 ratio in the per-protocol set (PPS). Model variables were screened using the least absolute shrinkage selection operator (LASSO) regression, univariate analysis, and multifactor logistic regression. Then, nine ML algorithms are integrated to build the model and compare the model effects. Individualized risk assessment was performed using the SHapley Additive exPlanation (SHAP) and nomograms, respectively. The model discrimination was evaluated by receiver operating characteristic curve (ROC), the calibration ability of the model was evaluated by calibration plot, and the clinical applicability of the model was evaluated by decision curve analysis (DCA). This study was approved by the Clinical Research Ethics Committee of China-Japan Friendship Hospital (2020-114-K73). Results: 690 patients were eligible to finish the complete follow-up in the PPS. After LASSO screening and multifactorial logistic regression analysis, physical activity level, taking antiplatelets, Traditional Chinese medicine treatment, Gensini score, Seattle Angina Questionnaire (SAQ)-exercise capacity score, and SAQ-anginal stability score were found to be predictors of the occurrence of CVE. The above predictors are modeled, and a comprehensive comparison of the modeling effectiveness of multiple ML algorithms is performed. The results show that the Light Gradient Boosting Machine (LightGBM) model is the best model, with an area under the curve (AUC) of 0.95 (95% CI = 0.91-1.00) for the test set, Accuracy: 0.90, Sensitivity: 0.87, and Specificity: 0.96. Interpretation of the model using SHAP highlighted the Gensini score as the most important predictor. Based on the multifactorial logistic regression modeling, a nomogram, and online calculators have been developed for clinical applications. Conclusion: We developed the LightGBM optimization model and the multifactor logistic regression model, respectively. The model is interpreted using SHAP and nomogram. This provides an option for early prediction of CVE in patients with SA combined with CHD.

The Influence of Cardiovascular Risk Factors and Hypogonadism on Cardiac Outcomes in an Aging Population of Beta-Thalassemia Patients

Beta-thalassemia major (β-TM) is a hereditary genetic disease worsened by many comorbidities due to transfusion-related iron despite chelation therapy. Since there has recently been an increase in life expectancy of patients to up to 50 years old, which influences the prevalence of these diseases and the time span for traditional cardiovascular risk factors to play their role, this study aims to evaluate their distribution and prevalence in a population of thalassemia major patients and their relationship with observed cardiovascular events and potential modifying factors. One hundred and fifty-nine β-TM patients with at least 15 years of follow-up were included in this study. The mean age was 40.9 ± 8.4 years; 28% had diabetes mellitus and 62% had hypogonadism. The cardiovascular risk assessed using algorithms (CUORE and Pooled Cohort Risk Equation—PCRE) was low, but 3.8% of patients had at least one episode of heart failure, 35.9% showed early signs of heart failure, 22% received a diagnosis of diastolic dysfunction, and 21.4% showed supraventricular arrhythmias. Hypogonadism was shown to be related to the occurrence of cardiovascular events. The chronic accumulation of iron in the heart and the specific metabolic profile, mainly observed in patients with hypogonadism, allows us to define β-TM as a condition with a high level of cardiovascular risk from many points of view (iron-related myopathy, atherosclerosis and arrhythmias), which requires better stratification tools and a specific follow-up program.

Long term prognostic implication of newly detected abnormal glucose tolerance among patients with stable cardiovascular disease: a population-based cohort study

Background

Fasting plasma glucose (FPG) and 2-h post challenge plasma glucose (2 h-PCPG), whether as continuous or categorical variables, are associated with incident cardiovascular disease (CVD) and diabetes; however, their role among patients with existing CVD is a matter of debate. We aimed to evaluate associations of different glucose intolerance states with recurrent CVD and incident diabetes among subjects with previous CVD.

Methods

From a prospective population-based cohort, 408 Iranians aged  ≥  30 years, with history of CVD and without known diabetes were included. Associations of impaired fasting glucose (IFG) according to the American Diabetes Association (ADA) and World Health Organization (WHO) criteria, impaired glucose tolerance (IGT), newly diagnosed diabetes (NDM) with outcomes of interest were determined by multivariable Cox proportional hazard models after adjustment for traditional risk factors. Furthermore, FPG and 2 h-PCPG were entered as continuous variables.

Results

Over a decade of follow-up, 220 CVD events including 89 hard events (death, myocardial infarction and stroke) occurred. Regarding prediabetes, only IFG-ADA was associated with increased risk of hard CVD [hazard ratio(HR), 95%CI: 1.62,1.03–2.57] in the age-sex adjusted model. In patients with NDM, those with FPG ≥ 7 mmol/L were at higher risk of incident CVD/coronary heart disease(CHD) and their related hard outcomes (HR ranged from 1.89 to 2.84, all P < 0.05). Moreover, those with 2 h-PCPG ≥ 11.1 mmol/L had significant higher risk of CVD (1.46,1.02–2.11), CHD (1.46,1.00–2.15) and hard CHD (1.95:0.99–3.85, P = 0.05). In the fully adjusted model, each 1 SD increase in FPG was associated with 20, 27, 15 and 25% higher risk of CVD, hard CVD, CHD and hard CHD, respectively; moreover each 1 SD higher 2 h-PCPG was associated with 21% and 16% higher risk of CVD, and CHD, respectively. Among individuals free of diabetes at baseline (n = 361), IFG-ADA, IFG-WHO and IGT were significantly associated with incident diabetes (all P < 0.05); significant associations were also found for FPG and 2 h-PCPG as continuous variables (all HRs for 1-SD increase > 2, P < 0.05).

Conclusions

Among subjects with stable CVD, NDM whether as high FPG or 2 h-PCPG, but not pre-diabetes status was significantly associated with CVD/CHD and related hard outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02950-y.

Addition of routine blood biomarkers to TIMI risk score improves predictive performance of 1-year mortality in patients with ST-segment elevation myocardial infarction

Background

Several biomarkers have been proposed as independent predictors of poor outcomes in ST-segment elevation myocardial infarction (STEMI). We investigated whether adding information obtained from routine blood tests including hypoxic liver injury (HLI), dysglycemia, anemia, and high neutrophil to lymphocyte ratio (NLR) could improve the prognostic performance of the TIMI risk score for the prediction of 1-year mortality.

Methods

A total of 1057 patients with STEMI undergoing primary percutaneous coronary intervention (PCI) between 2007 and 2014 were retrospectively enrolled from 4-regional hospitals. HLI and dysglycemia were defined as serum transaminase > twice the normal upper limit and glucose < 90 or > 250 mg/dL, respectively. The effect of adding biomarkers to the TIMI risk score on its discriminative ability was assessed using c-statistic, net reclassification improvement (NRI), and integrated discrimination improvement (IDI).

Results

The 1-year mortality rate was 7.1%. The best cutoff value of NLR for the prediction of 1-year mortality was 4.3 (sensitivity, 67%; specificity, 65%). HLI (HR 2.019; 95% CI 1.104–3.695), dysglycemia (HR 2.535; 95% CI 1.324–3.923), anemia (HR 2.071; 95% CI 1.093–3.923), and high NLR (HR 3.651; 95% CI 1.927–6.918) were independent predictors of 1-year mortality. When these 4 parameters were added to the TIMI risk score, the c-statistic significantly improved from 0.841 to 0.876 (p < 0.001), and the NRI and IDI were estimated at 0.203 (95% CI 0.130–0.275; p < 0.001) and 0.089 (95% CI 0.060–0.119; p < 0.001), respectively.

Conclusions

The addition of HLI, dysglycemia, anemia, and high NLR to the TIMI risk score may be useful for very early risk stratification in patients with STEMI receiving primary PCI.

Factors associated with platelet reactivity during dual antiplatelet therapy in patients with diabetes after acute coronary syndrome

Antiplatelet drugs are prescribed without considering the diabetic status of the patient. The objective of the current investigation was to determine the impact of clinical factors, CYP4F2 enzyme and 20-hydroxyeicosatetraenoic acid (20-HETE) concentrations on high on-treatment platelet reactivity in patients with diabetes treated with antiplatelet drugs following acute coronary syndromes. A total of 667 patients were included in the study. Dual antiplatelet drug loading dosages with aspirin (300 mg) and ticagrelor (180 mg) or clopidogrel (600 mg) were prescribed to all the studied patients. Testing of platelet aggregation was performed the day after loading antiplatelet drug dosages. Platelet aggregation test was done according to the classical Born method. Multivariate binary regression analysis demonstrated that insulin use and higher 20-HETE concentration increased the odds of high on-treatment platelet reactivity during the initiation of antiplatelet drug therapy (OR: 3.968, 95% CI: 1.478-10.656, p = 0.006 and OR: 1.139, 95% CI: 1.073-1.210, respectively, p < 0.001). Ticagrelor use decreased the odds of developing high on-treatment platelet reactivity (OR: 0.238, 95% CI: 0.097-0.585, p = 0.002). Data from this study revealed that high on-treatment platelet reactivity during dual antiplatelet therapy in patients with diabetes may depend on such factors as insulin prescription and 20-HETE concentration.

Does depressed persons with non-cardiovascular morbidity have a higher risk of CVD? A population-based cohort study in Sweden

BACKGROUND

Depression often co-exists with non-cardiovascular morbid conditions. Whether this comorbidity increases the risk of cardiovascular disease has so far not been studied. Thus, the aim of this study was to determine if non-cardiovascular morbidity modifies the effect of depression on future risk of CVD.

METHODS

Data was derived from the PART study (acronym in Swedish for: Psykisk hälsa, Arbete och RelaTioner: Mental Health, Work and Relationships), a longitudinal cohort study on mental health, work and relations, including 10,443 adults (aged 20-64 years). Depression was assessed using the Major Depression Inventory (MDI) and self-reported data on non-cardiovascular morbidity was assessed in 1998-2000. Outcomes of CVD were assessed using the National Patient Register during 2001-2014.

RESULTS

Both depression (HR 1.5 (95% CI, 1.1, 2.0)) and non-cardiovascular morbidity (HR 2.0 (95% CI, 1.8, 2.6)) were associated with an increased future risk of CVD. The combined effect of depression and non-cardiovascular comorbidity on future CVD was HR 2.1 (95%, CI 1.3, 3.4) after adjusting for age, gender and socioeconomic position. Rather similar associations were seen after further adjustment for hypertension, diabetes and unhealthy lifestyle factors.

CONCLUSION

Persons affected by depression in combination with non-cardiovascular morbidity had a higher risk of CVD compared to those without non-cardiovascular morbidity or depression alone.

Incidence and risk factors for recurrent cardiovascular disease in middle-eastern adults: a retrospective study

BACKGROUND

Individuals with established cardiovascular disease (CVD) and risk factors such as age, smoking, hypertension, and diabetes mellitus are at an increased risk of recurrent cardiovascular events and death. The incidence rate of recurrent CVD events varies between countries and populations. The United Arab Emirates (UAE) has one of the highest age-standardized death rates for CVD worldwide. The aim of our study was to estimate the incidence rates and determine the predictors of recurrent CVD events among UAE nationals.

METHODS

We investigated an outpatient-based cohort of patients with a history of CVD visiting Tawam Hospital between April 1, 2008 and December 31, 2008. They were followed-up until July 31, 2018. Univariable and multivariable Cox proportional hazards regression models were used to determine the association between major CVD risk factors and the risk of CVD recurrence.

RESULTS

A total of 216 patients (167 males, 49 females) with a history of CVD were included. They were followed for a median (interquartile range) of 8.1 (5.5-9.3) years, with a total of 1184 patient-years of follow-up. The overall incidence rate of recurrent CVD events was 92.1 per 1000 patient-years. The 8-year cumulative incidence was 73.7%. Age, female sex, and diabetes mellitus were significant predictors of recurrent CVD events, where females had a 1.96 times higher risk of recurrent CVD events than males.

CONCLUSION

Significant predictors of recurrent CVD events are older age, female sex, and diabetes mellitus. The incidence rate of recurrent CVD events was 92.1 per 1000 patient-years. Preventive measures, based on international guidelines for CVD management, may improve CVD morbidity and mortality in the UAE population.

CD36 gene polymorphism rs1761667 (G > A) is associated with hypertension and coronary artery disease in an Iranian population

Background

CD36 is associated with regulation of lipid metabolism, atherosclerosis, and blood pressure. Moreover, its variation may be involved in the development of hypertension and/or coronary artery disease (CAD). The present study was conducted to investigate the possible association of CD36 rs1761667 (G > A) polymorphism with hypertension and/or CAD in the southeastern of Iran.

Methods

The present observational study was composed of 238 subjects who were admitted for coronary angiography, and divided into four groups: 1) hypertensive without CAD (H-Tens, n = 52); 2) hypertensive with CAD (CAD + H-Tens, n = 57); 3) CAD without hypertension (CAD, n = 65); and 4) non-hypertensive without CAD as the control group (Ctrl, n = 64). The CD36 rs1761667 polymorphism was genotyped with PCR-RFLP method. Association between CD36 rs1761667 genotypes and the risk of CAD and hypertension was assessed using multinomial regression by adjusting for age, sex, creatinine, fasting blood sugar (FBS), systolic blood pressure (SBP) and diastolic blood pressure (DBP).

Results

In the present study, minor allele (A) frequency was 0.36. The genotype, but not allele frequency of the CD36 rs1761667 was significantly different between the four study groups (p = 0.003). Furthermore, using a recessive inheritance model CD36 rs1761667 polymorphism was significantly associated with an increased risk of CAD with hypertension (OR = 5.677; 95% CI = 1.053–30.601; p = 0.043). However, using the dominant model of CD36 rs1761667 had a protective effect on H-Tens and CAD patients.

Conclusion

The present findings revealed an association between CD36 rs1761667 polymorphism and susceptibility to hypertension and/or CAD in a southeastern Iranian population.

The association between diabetes mellitus and reduction in myocardial glucose uptake: a population-based 18F-FDG PET/CT study

BACKGROUND

In diabetes, dysregulated substrate utilization and energy metabolism of myocardium can lead to heart failure. To examine the dynamic changes of myocardium, most of the previous studies conducted dynamic myocardial PET imaging following euglycemic-hyperinsulinemic clamp, which involves complicated procedures. In comparison, the whole-body 18F-FDG PET/CT scan is a simple and widely used method. Therefore, we hope to use this method to observe abnormal myocardial glucose metabolism in diabetes and determine the influencing factors.

METHODS

We retrospectively analyzed PET/CT images of 191 subjects from our medical examination center. The levels of FDG uptake in myocardium were visually divided into 4 grades (Grade 0-3, from low to high). The differences in clinical and metabolic parameters among diabetes mellitus (DM), impaired fasting glucose (IFG), and normal fasting glucose (NFG) groups were analyzed, as well as their associations with myocardial FDG uptake.

RESULTS

Compared with NFG and IFG groups, DM group had more cardiovascular-related risk factors. The degree of myocardial FDG uptake was significantly decreased in DM group; when myocardial FDG uptake ≤ Grade 1, the sensitivity of DM prediction was 84.0%, and the specificity was 58.4%. Univariate analysis showed that the myocardial FDG uptake was weakly and negatively correlated with multiple metabolic-related parameters (r = - 0.173~ - 0.365, P < 0.05). Multivariate logistic regression analysis showed that gender (male), HOMA-IR and nonalcoholic fatty liver disease (NAFLD) were independent risk factors for poor myocardial FDG uptake.

CONCLUSIONS

Diabetes is associated with decreased myocardial glucose metabolism, which is mediated by multiple metabolic abnormalities.

Evaluation of health status and its predictor among university staff in Nigeria

BACKGROUND

Hypertension, diabetes mellitus and obesity share some characteristics in relation to diagnosis, management, and prevention. Overweight, obesity and waist-hip ratio (WHR) are associated with increased risk for development of diabetes and hypertension. Surveillance and regular screening exercises are essential in control and prevention of overweight, obesity, diabetes and hypertension. There is limited literature that reported on these health status parameters among university staff in low- and middle-income countries such as Nigeria. It is currently unclear whether Nigerian have a high or low proportion of metabolic risk factors. Therefore, the study aims to examine health status parameters and their predictors among university staff in Nigeria.

METHODS

The study used a cross-sectional descriptive design. Data were collected from 280 university staff in Nigeria. A self-administered questionnaire with sections for sociodemographic data and physical assessment was used to gather information from the participants. Data were analysed using the Statistical Package for Social Science (IBM-SPSS version 25). Univariable and multivariable logistic regression was conducted to explore the association between predictors and health status parameters of the participants.

RESULT

The response rate was 87.5%. University staff had mean systolic blood pressure of 132.04 mmHg ± 19.20 mmHg, diastolic blood pressure of 78.11 mmHg ± 10.81 mmHg, body mass index of 27.74 ± 5.22, waist-hip ratio of 0.88 ± 0.68 and random blood sugar of 98.65 ± 21.30 mg/dL. Predictors of high blood pressure were age (adjusted odds ratio [aOR] = 1.10, CI 95%: [1.05-1.14]) and gender (aOR = 0.5, CI 95%: [0.8-0.9]) and predictors of body mass index were gender (aOR = 2.3, CI 95%: [1.3-4.2]) and religion (aOR = 0.3, CI 95%: [0.2-0.7]). Gender and age had statistically significant association with waist-hip ratio and random blood sugar respectively.

CONCLUSION

The prevalence rates of high blood pressure and random blood sugar; overweight, obesity and risk WHR are on the increase compared to previous studies. Lifestyle modification, organized and explicit health campaigns coupled with regular screening and surveillance will contribute to the prevention and control of noncommunicable diseases.

Risk factors for prehypertension and their interactive effect: a cross- sectional survey in China

BACKGROUND

Individuals with prehypertension are at higher risk of developing hypertension and cardiovascular diseases, while the interaction between factors may aggravate prehypertension risk. Therefore, this study aimed to evaluate the risk factors for prehypertension in Chinese middle-aged and elderly adults, and explore the potentially interactive effect of evaluated factors.

METHODS

All the participants that came from a community based cross-sectional survey were investigated in Bengbu, China, by being interviewed with a questionnaire. Body mass index (BMI), Waist circumference (WC) and lipid accumulation product (LAP) that reflect participants' obesity were also calculated. In addition, logistic regression model was applied to explore the risk factors of prehypertension, followed by the assessment of the interactive effects between risk factors on prehypertension by the relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP) and synergy index (SI).

RESULTS

A total of 1777 participants were enrolled in this study, among which the prevalence of normtension, prehypertension and hypertension were 41.70%, 33.93% and 24.37% respectively. According to the multivariate logistic regression analysis, age (OR: 1.01, 95%CI: 1.00-1.02), smoking (OR: 1.67, 95%CI: 1.22-2.29), family history of cardiovascular diseases (OR: 1.52, 95%CI: 1.14-2.02), general obesity (OR: 1.51, 95%CI: 1.15-1.97) and LAP (OR: 2.58, 95%CI: 1.76-3.80) were all defined as the major factors that significantly related with the risk of prehypertension. When identifying prehypertension risk, the receiver-operating characteristics (ROC) curves (AUC) analysis indicated that LAP performed better than BMI in males (Z = 2.05, P = 0.03) and females (Z = 2.12, P = 0.03), but was superior to WC only in females (Z = 2.43, P = 0.01). What is more, there were significant interactive effects of LAP with family history of cardiovascular diseases (RERI: 1.88, 95%CI: 0.25-3.51; AP: 0.44, 95%CI: 0.20-0.69; SI: 2.37, 95%CI: 1.22-4.60) and smoking (RERI: 1.99, 95%CI: 0.04-3.93; AP: 0.42, 95%CI: 0.17-0.67; SI: 2.16, 95%CI: 1.68-4.00) on prehypertension risk. The value of AP (0.40, 95%CI: 0.03-0.77) also indicated a significant interaction between family history of cardiovascular diseases and smoking on prehypertension.

CONCLUSION

Prehypertension is currently prevalent in Chinese adults. This study indicated that age, family history of cardiovascular diseases, smoking, general obesity and LAP were significantly related with prehypertension risk. Furthermore, interactive effects on risk of prehypertension had been demonstrated in this study as well, which would help researchers to build strategy against prehypertension more comprehensively and scientifically.

Is single-child family associated with cardio-metabolic risk factors: the CASPIAN-V study

BACKGROUND

In the present study, the association of the cardio-metabolic risk factors and the status of single-child family were studied in a national representative sample of Iranian children and adolescents.

METHODS

This cross sectional study was conducted as the fifth round of "Childhood and Adolescence Surveillance and PreventIon of Adult Non- communicable disease" surveys. The students' questionnaire was derived from the World Health Organization-Global School Student Health Survey. Using survey data analysis methods, data from questionnaires'; anthropometric measures and biochemical information analyzed by logistic regression analysis.

RESULTS

Overall, 14,274 students completed the survey (participation rate: 99%); the participation rate for blood sampling from students was 91.5%. Although in univariate logistic regression model, single child students had an increased risk of abdominal obesity [OR: 1.37; 95% CI: 1.19-1.58)], high SBP [OR: 1.58; 95% CI:1.17-2.14)], high BP [OR: 1.21; 95% CI:1.01-1.45)] and generalized obesity [OR: 1.27; 95% CI:1.06-1.52)], in multiple logistic regression model, only association of single child family with abdominal obesity remained statistically significant [OR: 1.28; 95% CI:1.1-1.50)]. Also in multivariate logistic regression model, for each increase of a child in the family the risk of abdominal obesity [OR: 0.95; 95% CI: 0.91-0.97), high SBP [OR: 0.88; 95% CI: 0.81-0.95)] and generalized obesity [OR: 0.95; 95% CI: 0.91-0.99)] decreased significantly.

CONCLUSION

The findings of this study serve as confirmatory evidence on the association of cardio-metabolic risk factors with single-child family in children and adolescents. The findings of study could be used for better health planning and more complementary research.

Metformin restores electrophysiology of small conductance calcium-activated potassium channels in the atrium of GK diabetic rats

BACKGROUND

Small conductance calcium-activated potassium channels (SK channels) play a critical role in action potential repolarization in cardiomyocytes. Recently, the potential anti-arrhythmic effect of metformin in diabetic patients has been recognized, yet the underlying mechanism remains elusive.

METHODS

Diabetic Goto-Kakizaki (GK) rats were untreated or treated with metformin (300 mg/kg/day) for 12 weeks, and age-matched Wistar rats were used as control (n = 6 per group). Electrocardiography, Hematoxylin-eosin staining and Masson's trichome staining were performed to assess cardiac function, histology and fibrosis. The expression levels of the SK channels in the myocardium were determined by real-time PCR and Western blotting. The electrophysiology of the SK channels in the cardiomyocytes isolated from the three groups of rats was examined by patch clamp assay, with specific blockade of the SK channels with apamin.

RESULTS

Metformin treatment significantly reduced cardiac fibrosis and alleviated arrhythmia in the diabetic rats. In the atrial myocytes from control, GK and metformin-treated GK rats, the expression of KCa2.2 (SK2 channel) was down-regulated and the expression of KCa2.3 (SK3 channel) was up-regulated in the atrium of GK rats as compared with that of control rats, and metformin reversed diabetes-induced alterations in atrial SK channel expression. Moreover, patch clamp assay revealed that the SK current was markedly reduced and the action potential duration was prolonged in GK atrial myocytes, and the SK channel function was partially restored in the atrial myocytes from metformin-treated GK rats.

CONCLUSIONS

Our data suggests an involvement of the SK channels in the development of arrhythmia under diabetic conditions, and supports a potential beneficial effect of metformin on atrial electrophysiology.

Is there a C-reactive protein value beyond which one should consider infection as the cause of acute heart failure?

Background

Heart Failure (HF) is a low grade inflammatory condition. High sensitivity C-reactive protein (hsCRP) is an established marker of inflammation. A cut-off value of hsCRP beyond which an infection should be sought has never been studied in HF. We aimed to determine the best hsCRP cut-off for infection prediction in acute HF.

Methods

We analyzed patients included in an acute HF registry – EDIFICA (Estratificação de Doentes com InsuFIciência Cardíaca Aguda). Admission hsCRP measurement was available as part of the registry’s protocol. Patients with acute coronary syndrome as the cause of acute HF were excluded from the registry. Infection was considered according to the diagnosis registered in the discharge record. A receiver-operating characteristic (ROC) curve was used to determine the best hsCRP cut-off for infection prediction.

Results

We studied 615 patients. Mean age was 76 years, 45.2% were male, 60.3% had systolic dysfunction. Median admission hsCRP was 20.3 (9.5–55.5)mg/L; in 41.6% the cause of decompensation was an infection. The area under the ROC curve for admission hsCRP in the prediction of infection was 0.79 (0.76–0.83); the best hsCRP cut-off was 25 mg/L with a sensitivity of 72.7%, specificity 77.2%, positive predictive value 69.4% and negative predictive value 79.9%. Age and elevated hsCRP independently associated with an infection as the precipitant of acute HF.

Conclusions

We suggest 25 mg/L as a cut-off beyond which an infection should be sought underlying acute HF. Almost 80% of the patients with hsCRP< 25 mg/L are not infected and 69.4% of those with higher hsCRP have a concomitant infection.

Homocysteine is a bystander for ST-segment elevation myocardial infarction: a case-control study

Background

Homocysteine has been long considered a risk factor for atherosclerosis. However, cardiovascular events cannot be reduced through homocysteine lowering by B vitamin supplements. Although several association studies have reported an elevation of serum homocysteine levels in cardiovascular diseases, the relationship of homocysteine with ST-segment elevation myocardial infarction (STEMI) is not well established.

Methods

We prospectively enrolled STEMI patients who were consecutively admitted to an intensive care unit following coronary intervention in a single medical center in Taiwan. Control subjects were individuals who presented to the outpatient or emergency department with acute chest pain but subsequently revealed patent coronary arteries by coronary arteriography. The association between serum homocysteine levels and STEMI was investigated. A culture system using human coronary artery endothelial cells was also established to examine the toxic effects of homocysteine at the cellular level.

Results

Patients with chest pain were divided into two groups. The STEMI group included 56 patients who underwent a primary percutaneous coronary intervention. The control group included 17 subjects with patent coronary arteries. There was no difference in serum homocysteine levels (8.4 ± 2.2 vs. 7.6 ± 1.9 μmol/L, p = 0.142). When stratifying STEMI patients by the Killip classification into higher (Killip III-IV) and lower (Killip I-II) grades, CRP (3.3 ± 4.1 vs. 1.4 ± 2.3 mg/L, p = 0.032), peak creatine kinase (3796 ± 2163 vs. 2305 ± 1822 IU/L, p = 0.023), and SYNTAX scores (20.4 ± 11.1 vs. 14.8 ± 7.6, p = 0.033) were significantly higher in the higher grades, while serum homocysteine levels were similar. Homocysteine was not correlated with WBCs, CRP, or the SYNTAX score in STEMI patients. In a culture system, homocysteine at even a supraphysiological level of 100 μmol/L did not reduce the cell viability of human coronary artery endothelial cells.

Conclusions

Homocysteine was not elevated in STEMI patients regardless of Killip severity, suggesting that homocysteine is a bystander instead of a causative factor of STEMI. Our study therefore supports the current notion that homocysteine-lowering strategies are not essential in preventing cardiovascular disease.

Independent association of resting energy expenditure with blood pressure: confirmation in populations of the African diaspora

BACKGROUND

Obesity is a major risk factor for hypertension, however, the physiologic mechanisms linking increased adiposity to elevations in blood pressure are not well described. An increase in resting energy expenditure (REE) is an obligatory consequence of obesity. Previous survey research has demonstrated that REE is an independent predictor of blood pressure, and eliminates the co-linear association of body mass index. This observation has received little attention and there have been no attempts to provide a causal explanation.

METHODS

At baseline in an international comparative study on obesity, 289 participants aged 25-44 were recruited from communities in the US, the Seychelles, Ghana and South Africa and had REE measured with indirect calorimetry. All participants were thought to be free of major illness.

RESULTS

In multivariate regression models, both systolic and diastolic blood pressure were positively associated with REE (p < 0.01), while body mass index and fat mass were negatively correlated with systolic blood pressure (p < 0.01, and p < 0.05 respectively), but not diastolic blood pressure.

CONCLUSIONS

These data confirm previous reports and suggest that a common physiologic abnormality links REE and blood pressure. Elevated catecholamines, a putative metabolic characteristic of obesity, is a possible candidate to explain this association. The direct role of excess adipose tissue is open to question.

Nutrition in primary and secondary prevention of cardiovascular risk in the continental and Mediterranean regions of Croatia

BACKGROUND

The aim of this observational study was to evaluate the effect of Mediterranean and continental nutrition on cardiovascular risk in patients with acute and chronic coronary heart disease in Croatia.

METHODS

The study included 1284 patients who were hospitalized in a 28-month period due to acute or chronic ischaemic heart disease in hospitals across Croatia. An individual questionnaire was prepared which enabled recording of various cardiovascular risk factors.

RESULTS

Patients with chronic coronary artery disease have a better index of healthy diet than patients with acute coronary disease. Women have a better index of diet than men in both Croatian regions. When the prevalence of risk factors (impaired glucose tolerance, diabetes mellitus types I and II, hypercholesterolaemia, hypertriglyceridaemia and hypertension) in patients with Mediterranean and continental nutrition is compared, a trend is seen for patients who have risk factors to consume healthier food.

CONCLUSION

The Mediterranean diet is associated with reduced risk of developing cardiovascular disease. This effect is more evident in patients with known cardiovascular disease.

PR interval prolongation in coronary patients or risk equivalent: excess risk of ischemic stroke and vascular pathophysiological insights

BACKGROUND

Whether PR prolongation independently predicts new-onset ischemic events of myocardial infarction and stroke was unclear. Underlying pathophysiological mechanisms of PR prolongation leading to adverse cardiovascular events were poorly understood. We investigated the role of PR prolongation in pathophysiologically-related adverse cardiovascular events and underlying mechanisms.

METHODS

We prospectively investigated 597 high-risk cardiovascular outpatients (mean age 66 ± 11 yrs.; male 67%; coronary disease 55%, stroke 22%, diabetes 52%) for new-onset ischemic stroke, myocardial infarction (MI), congestive heart failure (CHF), and cardiovascular death. Vascular phenotype was determined by carotid intima-media thickness (IMT).

RESULTS

PR prolongation >200 ms was present in 79 patients (13%) at baseline. PR prolongation >200 ms was associated with significantly higher mean carotid IMT (1.05 ± 0.37 mm vs 0.94 ± 0.28 mm, P = 0.010). After mean study period of 63 ± 11 months, increased PR interval significantly predicted new-onset ischemic stroke (P = 0.006), CHF (P = 0.040), cardiovascular death (P < 0.001), and combined cardiovascular endpoints (P < 0.001) at cut-off >200 ms. Using multivariable Cox regression, PR prolongation >200 ms independently predicted new-onset ischemic stroke (HR 8.6, 95% CI: 1.9-37.8, P = 0.005), cardiovascular death (HR 14.1, 95% CI: 3.8-51.4, P < 0.001) and combined cardiovascular endpoints (HR 2.4, 95% CI: 1.30-4.43, P = 0.005). PR interval predicts new-onset MI at the exploratory cut-off >162 ms (C-statistic 0.70, P = 0.001; HR: 8.0, 95% CI: 1.65-38.85, P = 0.010).

CONCLUSIONS

PR prolongation strongly predicts new-onset ischemic stroke, MI, cardiovascular death, and combined cardiovascular endpoint including CHF in coronary patients or risk equivalent. Adverse vascular function may implicate an intermediate pathophysiological phenotype or mediating mechanism.

Cardiac tissue oxidative stress and inflammation after vitamin D administrations in high fat- diet induced obese rats

BACKGROUND

Obesity is associated with numerous metabolic and inflammatory disorders. The current study was aimed to evaluate the effects of vitamin D administration on the markers of oxidative stress and inflammation in the cardiac tissue of high-fat diet induced obese rats.

METHODS

In the beginning of the study, 40 male Wistar rats were divided into two groups: normal diet (ND) and high fat diet (HFD) for 16 weeks; then each group subdivided into two groups including: ND, ND + vitamin D, HFD and HFD + vitamin D. Vitamin D supplementation was done for 5 weeks at 500 IU/kg dosage. Tumor necrosis factor (TNF)-α concentration and markers of oxidative stress including glutathione peroxidase (GPx), superoxide dismutase (SOD), malondialdehyde (MDA) and catalase (CAT) concentrations in the cardiac tissue and serum concentrations of lipids in rats were determined using ELISA kits and spectrophotometry methods respectively.

RESULTS

According to our results, GPx activity in ND and ND + vitamin D group was significantly higher compared with HFD group. Similarly, SOD activity was also significantly increased in ND + vitamin D group compared with ND and HFD groups. Moreover, vitamin D administration, significantly reduced catalase activity in ND + vitamin D and HFD + vitamin D groups (P < 0.05). TNF-α concentration in heart tissue in ND + vitamin D group significantly reduced compared with ND group. Cardiac tissue MDA concentration in baseline or after vitamin D administration did not changed significantly.

CONCLUSION

Vitamin D improved cardiac oxidative stress and inflammatory markers in HFD induced obese rats. Further studies in human models are needed to further confirm the use of this nutrient in daily clinical practice.

Regional and hospital variations in the extent of decline in the proportion of percutaneous coronary interventions performed for nonacute indications - a nationwide population-based study

Background

The volume and percentage of percutaneous coronary interventions (PCIs) performed for nonacute indications have declined in the United States since 2007. However, little is known if similar trends occurred in Taiwan.

Methods

We used data from Taiwan National Health Insurance inpatient claims to examine the regional and hospital variations in the extent of decline in the percentage of nonacute indication PCIs from 2007 to 2012.

Results

The volume of total PCIs persistently increased from 29,032 in 2007 to 35,811 in 2010 and 37,426 in 2012. However, the volume of nonacute indication PCIs first increased from 7916 in 2007 to 9143 in 2009 and then decreased to 8666 in 2012. The percentage of nonacute indication PCIs steadily decreased from 27% in 2007 to 26% in 2009 and then to 23% in 2012, a − 15% change. The extent of decline was largest in the North region (from 27% to 21%, a − 22% change) and least in Kaopin region (from 20% to 18%, a − 13% change). Of the 71 hospitals studied, 14 did not show a decreasing trend. Five of the 14 hospitals even showed an increasing trend, with a percentage change >10% between 2007 and 2012. In 2012, 6 hospitals had a nonacute indication PCI percentage >35%.

Conclusions

In Taiwan, four-fifths of the hospitals showed a decline in the percentage of nonacute indication PCIs from 2007 to 2012. It is plausible that Taiwanese cardiologists would have been influenced by the recommendations of crucial US trials and guidelines.

Secondary prevention strategies after an acute ST-segment elevation myocardial infarction in the AMI code era: beyond myocardial mechanical reperfusion

BACKGROUND

The AMI code is a regional network enhancing a rapid and widespread access to reperfusion therapy (giving priority to primary angioplasty) in patients with acute ST-segment elevation myocardial infarction (STEMI). We aimed to assess the long-term control of conventional cardiovascular risk factors after a STEMI among patients included in the AMI code registry.

DESIGN AND METHODS

Four hundred and fifty-four patients were prospectively included between June-2009 and April-2013. Clinical characteristics were collected at baseline. The long-term control of cardiovascular risk factors and cardiovascular morbidity/mortality was assessed among the 6-months survivors.

RESULTS

A total of 423 patients overcame the first 6 months after the STEMI episode, of whom 370 (87%) underwent reperfusion therapy (363, 98% of them, with primary angioplasty). At 1-year follow-up, only 263 (62%) had adequate blood pressure control, 123 (29%) had LDL-cholesterol within targeted levels, 126/210 (60%) smokers had withdrawn from their habit and 40/112 (36%) diabetic patients had adequate glycosylated hemoglobin levels. During a median follow-up of 20 (11-30) months, cumulative mortality of 6 month-survivors was 6.1%, with 9.9% of hospital cardiovascular readmissions. The lack of assessment of LDL and HDL-cholesterol were significantly associated with higher mortality and cardiovascular readmission rates.

CONCLUSIONS

Whereas implementation of the AMI code resulted in a widespread access to rapid reperfusion therapy, its long-term therapeutic benefit may be partially counterbalanced by a manifestly suboptimal control of cardiovascular risk factors. Further efforts should be devoted to secondary prevention strategies after STEMI.