Acute insulin resistance in ST-segment elevation myocardial infarction in non-diabetic patients is associated with incomplete myocardial reperfusion and impaired coronary microcirculatory function

Stress, Hyperglycemia, and Insulin Resistance Correlate With Neutrophil Activity and Impact Acute Myocardial Infarction Outcomes

Introduction Acute insulin resistance (IR) and hyperglycemia are frequently observed during acute myocardial infarction (AMI), significantly influencing both immediate and long-term patient outcomes, irrespective of diabetic status. Neutrophilia and increased neutrophil activity, which are common in these scenarios, have been associated with poorer prognoses, as demonstrated in our recent findings. While it is well established that neutrophils and stress-induced hyperglycemia exacerbate inflammation and hinder recovery, the complex interplay between these factors and their combined impact on AMI prognosis remains inadequately understood. This study aims to investigate the effects of stress hyperglycemia and IR on AMI patients at the onset of the event and to elucidate the relationship between these metabolic disturbances and inflammatory markers, particularly neutrophils. Methods We conducted a longitudinal prospective study on 219 AMI patients at Elias Emergency Hospital in Bucharest, Romania, from April 2021 to September 2022. Patients were included within 24 hours of AMI with ST-segment elevation and excluded if they had acute infections or chronic inflammatory diseases. Blood samples were collected to study inflammatory biomarkers, including neutrophil extracellular traps (NETs), S100A8/A9, interleukin (IL)-1β, IL-18, and IL-6. Diabetic and pre-diabetic statuses were defined using glycated hemoglobin (HbA1c) and medical history (ADA 2019 criteria). To assess glycemic parameters, we employed the glycemia ratio (GR) and the homeostatic model assessment of insulin resistance (HOMA-IR) index, enabling a precise evaluation of stress hyperglycemia, acute IR, and their prognostic implications. Patients were stratified into groups based on GR calculations, categorized as under-average glycemia, normal glycemia, and stress hyperglycemia. Results The majority of patients in the stress hyperglycemia group exhibited an unfavorable prognosis. This group also demonstrated significantly elevated neutrophil counts and neutrophil-to-lymphocyte ratios (NLR). The GR was significantly and positively correlated with inflammation markers, including neutrophil count (Pearson's R = 0.181, P = 0.008) and NLR (Pearson's R = 0.318, P < 0.001), but showed no significant correlation with other evaluated inflammatory markers. Conclusions Our findings suggest that poor outcomes in AMI patients may be associated with stress hyperglycemia, as indicated by GR. AcuteIR, quantified by GR and HOMA-IR, exhibits a strong correlation with neutrophil count and NLR within the first 24 hours of AMI onset. However, no significant correlation was observed with other inflammatory markers, such as IL-1β, IL-18, and IL-6, underscoring the specific interplay between IR and neutrophil activity in this setting.

Prognostic value of triglyceride-glucose index for left ventricular remodeling in nondiabetic ST-elevation myocardial infarction patients

Background: The triglyceride-glucose (TyG) index is a marker of insulin resistance and is associated with cardiovascular mortality and morbidity. Left ventricular remodeling (LVR) after myocardial infarction (STEMI) is associated with poor prognosis. Methods: This retrospective study included 293 STEMI patients. Echocardiography was performed before discharge and 3 months after MI. Results: Compared with the non-LVR group, TyG index value was found to be higher in the LVR group (p < 0.001). Logistic regression analysis showed that higher maximal troponin I value, higher calculated TyG index value, higher N-terminal prohormone of brain natriuretic peptide level and the presence of anterior MI were independently associated with the development of LVR. Conclusion: A high TyG index level may contribute to the prediction of LVR in nondiabetic STEMI patients undergoing successful primary percutaneous coronary intervention.

The potential role of the triglyceride-glucose index in left ventricular systolic function and in-hospital outcomes for patients with acute myocardial infarction

BACKGROUND

A limited number of small-sample cohort studies have investigated the association between the triglyceride-glucose index and in-hospital prognosis. Moreover, the translational potential role of left ventricular systolic function - measured by left ventricular ejection fraction - combined with the triglyceride-glucose index in prioritizing patients with acute myocardial infarction at high risk of in-hospital major adverse cardiovascular events remains unknown.

AIM

To explore the potential role of the triglyceride-glucose index in left ventricular systolic function and in-hospital major adverse cardiovascular events in patients with acute myocardial infarction.

METHODS

The Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome project (CCC-ACS) was analysed for this study.

RESULTS

We included 43,796 patients with acute myocardial infarction. Patients with a higher triglyceride-glucose index showed an increased risk of major adverse cardiovascular events (adjusted odds ratio 1.46, 95% confidence interval 1.31-1.63). Interaction analyses revealed that left ventricular ejection fraction modified the relationship between the triglyceride-glucose index and major adverse cardiovascular events. Furthermore, patients with acute myocardial infarction were categorized by the triglyceride-glucose index and left ventricular ejection fraction; the low left ventricular ejection fraction/high triglyceride-glucose index group showed the highest risk of major adverse cardiovascular events (adjusted odds ratio 2.14, 95% confidence interval 1.58-2.89).

CONCLUSIONS

In a comprehensive nationwide acute myocardial infarction registry conducted in China, a higher triglyceride-glucose index was found to be associated with in-hospital major adverse cardiovascular events, and this was particularly evident among patients with a lower left ventricular ejection fraction. Moreover, the triglyceride-glucose index combined with left ventricular ejection fraction was helpful for risk stratification of patients with acute myocardial infarction.

Insulin resistance is associated with high-risk coronary artery plaque composition in asymptomatic men between 65 and 75 years and no diabetes: A DANCAVAS cross-sectional sub-study

BACKGROUND AND AIMS

Insulin resistance (IR) and pre-diabetes are associated with an increased risk of cardiovascular disease (CVD). We aimed to investigate vulnerable plaque composition in relation to IR and pre-diabetes in asymptomatic non-diabetic men.

METHODS

All participants underwent a contrast-enhanced coronary computed tomography angiography (CCTA) to evaluate coronary artery plaque burden and plaque composition (necrotic core, dense calcium, fibrotic and fibrous-fatty volume). Homeostasis model assessment of IR (HOMA-IR) was used, and participants were stratified into tertiles. Participants underwent a standard oral glucose tolerance test (OGTT) and were categorized into 2 groups (normal glucose tolerance (NGT) or pre-diabetes). A multivariable linear regression model was used to evaluate the association between vulnerable plaque composition and IR or glycemic group.

RESULTS

Four-hundred-and-fifty non-diabetic men without known CAD were included. The mean age was 70 ± 3 years. Participants in the higher HOMA-IR tertile (H-IR) had higher median necrotic plaque volume compared to the lower HOMA-IR tertile (L-IR) (18.2 vs. 11.0 mm3, p = 0.02). H-IR tertile (β 0.37 [95% CI 0.10-0.65], p = 0.008), pack-years (β 0.07 [95% CI 0.007-0.14], p = 0.03) and total atheroma volume (TAV) (β 0.47 [95% CI 0.36-0.57], p < 0.001) remained associated with necrotic plaque volume in the multivariable linear regression model.

CONCLUSIONS

IR was associated with necrotic plaque volume in asymptomatic men without diabetes. Thus, even in asymptomatic men without diabetes, IR seems to have an incremental effect on necrotic plaque volume and vulnerable plaque composition.

Triglyceride-glucose index is associated with poor prognosis in acute coronary syndrome patients with prior coronary artery bypass grafting undergoing percutaneous coronary intervention

BACKGROUND

The triglyceride-glucose (TyG) index, which is a reliable substitute indicator for insulin resistance, has been considered an independent risk factor for long-term outcomes in patients with cardiovascular disease. However, it remains unknown whether the TyG index is associated with poor prognosis in acute coronary syndrome (ACS) patients with prior coronary artery bypass grafting (CABG) undergoing percutaneous coronary intervention (PCI).

METHODS

A total of 1158 ACS patients with prior CABG undergoing PCI were retrospectively studied. The TyG index was calculated by ln[fasting triglyceride (mg/dL) × fasting blood glucose (mg/dL)/2]. The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE), a composite of all-cause death, nonfatal myocardial infarction, nonfatal stroke, and unplanned repeat revascularization.

RESULTS

During a median of 42-month follow-up, 350 patients (30.2%) experienced at least one endpoint event. Based on the optimal cut-off value of the TyG index, patients were divided into the high TyG index group and the low TyG index group. Patients in the high TyG index group had higher risks of MACCE (35.3% vs. 25.3%, p < 0.001), major adverse cardiovascular events (MACE) (31.1% vs. 23.4%, p = 0.003), nonfatal stroke (4.2% vs. 1.9%, p = 0.022) and unplanned repeat revascularization (19.4% vs. 11.3%, p < 0.001) than those in the low TyG index group. Cox regression analysis demonstrated that there was an independent association between the TyG index and MACCE regardless of whether the TyG index was a continuous or categorical variable (HR 1.42, 95% CI 1.09-1.86, p = 0.009; HR 1.53, 95% CI 1.16-2.01, p = 0.003, respectively). Restricted cubic spline curve exhibited that the relationship between the TyG index and MACCE was linear (p for non-linear = 0.595, p for overall = 0.005). By incorporating the TyG index groups into baseline risk model, the accuracy of predicting MACCE was improved [AUC: baseline risk model, 0.618 vs. baseline risk model + TyG index groups, 0.636, p for comparison = 0.042].

CONCLUSIONS

The TyG index is independently associated with MACCE, suggesting that the TyG index may serve as a valid indicator for predicting poor prognosis in ACS patients with prior CABG undergoing PCI.

Myocardial Infarction Signs and Symptoms: Females vs. Males

Cardiovascular disease is the number one killer of females in the United States today, and myocardial infarction (MI) plays a role in many of these deaths. Females also present with more "atypical" symptoms than males and appear to have differences in pathophysiology underlying their MIs. Despite both differences in symptomology and pathophysiology being present in females versus males, a possible link between the two has not been studied extensively. In this systematic review, we analyzed studies examining differences in symptoms and pathophysiology of MI in females and males and evaluated possible links between the two. A search was performed for sex differences in MI in the databases PubMed, CINAHL (Cumulative Index to Nursing and Allied Health Literature) Complete, Biomedical Reference Collection: Comprehensive, Jisc Library Hub Discover, and Web of Science. Seventy-four articles were ultimately included in this systematic review. Typical symptoms for both ST-elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) such as chest, arm, or jaw pain were more common in both sexes, but females presented on average with more atypical symptoms such as nausea, vomiting, and shortness of breath. Females with MI also presented with more prodromal symptoms such as fatigue in days leading up to MI, had longer delays in presentation to the hospital after symptom onset, and were older with more comorbidities than males. Males on the other hand were more likely to have a silent or unrecognized MI, which concurs with their overall higher rate of MI. As they age, females have a decrease in antioxidative metabolites and worsened cardiac autonomic function than male. In addition, at all ages, females have less atherosclerotic burden than mles, have higher rates of MI not related to plaque rupture or erosion, and have increased microvasculature resistance when they have an MI. It has been proposed that this physiological difference is etiologic for the male-female difference in symptoms, but this has not been studied directly and is a promising area of future research. It is also possible that differences in pain tolerance between males and females may play a role in differing symptom recognition, but this has only been studied one time where females with higher pain thresholds were more likely to have unrecognized MI. Again, this is a promising area for future study for the early detection of MI. Finally, differences in symptoms for patients with different atherosclerotic burden and for patients with MI due to a cause other than plaque rupture or erosion has not been studied and are both promising avenues to improve detection and patient care in the future.

Triglyceride glucose index predicts in-hospital mortality in patients with ST-segment elevation myocardial infarction who underwent primary angiography

OBJECTIVES

To assess the correlation between triglyceride glucose (TyG) index and in-hospital mortality in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

A total of 2190 patients with STEMI who underwent primary angiography within 12 h from symptom onset were selected from the prospective, nationwide, multicenter CAMI registry. TyG index was calculated with the formula: Ln [fasting triglycerides (mmol/L) × fasting glucose (mmol/L)/2]. Patients were divided into three groups according to the tertiles of TyG index. The primary endpoint was in-hospital mortality.

RESULTS

Overall, 46 patients died during hospitalization, in-hospital mortality was 1.5%, 2.2%, 2.6% for tertile 1, tertile 2, and tertile 3, respectively. However, TyG index was not significantly correlated with in-hospital mortality in single-variable logistic regression analysis. Nonetheless, after adjusting for age and sex, TyG index was significantly associated with higher mortality when regarded as a continuous variable (adjusted OR = 1.75, 95% CI: 1.16-2.63) or categorical variable (tertile 3 vs. tertile 1: adjusted OR = 2.50, 95% CI: 1.14-5.49). Furthermore, TyG index, either as a continuous variable (adjusted OR = 2.54, 95% CI: 1.42-4.54) or categorical variable (tertile 3 vs. tertile 1: adjusted OR = 3.57, 95% CI: 1.24-10.29), was an independent predictor of in-hospital mortality after adjusting for multiple confounders in multivariable logistic regression analysis. In subgroup analysis, the prognostic effect of high TyG index was more significant in patients with body mass index < 18.5 kg/m² (P _interaction = 0.006).

CONCLUSIONS

This study showed that TyG index was positively correlated with in-hospital mortality in STEMI patients who underwent primary angiography, especially in underweight patients.

Triglyceride glucose index predicts all-cause mortality in oldest-old patients with acute coronary syndrome and diabetes mellitus

BACKGROUND

Acute coronary syndrome (ACS) and diabetes mellitus (DM) are the leading health risks for the elderly. Triglyceride-glucose (TyG) index is a novel and reliable indicator of insulin resistance (IR). This study aims to explore the relationship between the TyG index and all-cause mortality in oldest-old patients with ACS and DM.

METHODS

Seven hundred twenty hospitalized patients with ACS aged ≥ 80 years were enrolled, and 699 patients signed informed consent for the study. During the follow-up period, 37 were lost to follow-up, and the follow-up rate was 94.7%. 231 ACS patients with DM were selected for the study's analyses. Kaplan-Meier curve, Cox regression model and receiver operating characteristic (ROC) curve were used to analyze the association between the TyG index and all-cause mortality.

RESULTS

The mean age of participants was 81.58 ± 1.93 years, and 32.47% were women. Compared to TyG tertile 1, the Hazard Ratio (HR) [95% confidence interval (CI)] of all-cause mortality was 2.04 (1.09, 3.81) for TyG tertile 3 in the fully adjusted model. For the TyG index per standard deviation (SD) increment, the HR (95% CI) of all-cause mortality was 1.44 (1.13, 1.83). Further, the association between the TyG index and all-cause mortality was dose-response (P for trend = 0.026). ROC curve analyses indicated that the TyG index outperformed FBG and TG in the prediction of mortality risk and improved the prognostic value of the Gensini score combined with LVEF.

CONCLUSION

The TyG index predicts the risk of all-cause mortality in the oldest-old ACS patients with DM.

Influence of age on the association between the triglyceride-glucose index and all-cause mortality in patients with cardiovascular diseases

BACKGROUND

In patients with cardiovascular diseases, it is reported that the triglyceride-glucose index (TGI) potentially indicates prognosis. However, the results are controversial. Moreover, whether age has an impact on the predictive value of TGI remains unclear.

METHODS

Participants with cardiovascular diseases were enrolled using the China Health and Retirement Longitudinal Study (CHARLS) registry. TGI was calculated as ln (triglyceride×glucose/2). The survival status was recorded every 2 years in the follow-up waves. Multivariate regression analysis was carried out to determine the relationship between TGI levels and long-term all-cause mortality in patients grouped by different age. Patients younger than 65 years old were regarded as middle-aged group. Otherwise, they were classified as old group.

RESULTS

In total, 2923 patients with cardiovascular diseases and baseline blood test results were included. After 7 years of follow-up, 242 (8.91%) patients died. Cox regression analysis revealed that higher TGI levels were associated with a higher risk of long-term all-cause mortality in middle-aged participants (hazard ratio [HR], 3.64; 95% confidence interval [CI] 1.44-9.22, P = 0.006) but not in old participants (HR 1.20, 95% CI 0.62-2.32, P = 0.594, P for interaction = 0.017), after adjusting physical activity and other factors. Kaplan-Meier estimate analysis and restricted cubic spline curves showed similar results.

CONCLUSION

TGI was a promising marker for predicting all-cause mortality in middle-aged patients after cardiovascular diseases. Patients younger than 65 years old who have a higher level of TGI may develop a higher risk of all-cause mortality, and they are encouraged to control vascular risk factors and take more physical activity to improve their prognosis. Additionally, whether intervention in regulating TGI levels is beneficial for the prognosis of these patients needs further investigation.

Correlation of Insulin Resistance With Short-Term Outcome in Nondiabetic Patients With ST-Segment Elevation Myocardial Infarction

BACKGROUND

 Obviously, hyperglycemia and insulin resistance (IR) are common in patients with acute ST-segment elevation myocardial infarction (STEMI). Additionally, IR is a substantial risk factor for cardiovascular diseases. The study aims to evaluate the association between IR and short-term outcomes of acute STEMI patients without diabetes mellitus in the form of reperfusion success, the occurrence of heart failure, the development of arrhythmias, and mortality.

METHOD

 A cross-sectional study was done from August 2021 to December 2021 in two cardiology centers in Al-Sadr Teaching hospital and Basrah Oil hospital in Basrah, Southern Iraq. Sixty-one nondiabetic hospitalized patients with acute STEMI were included in the study. Twenty-five (41%) of them received thrombolytics and 36 (59%) were managed with percutaneous transluminal coronary angioplasty. From each patient, a fasting blood sample was taken for calculation of the Homeostasis Model Assessment for IR (HOMA-IR) and triglyceride glucose index (TyG) index. The patients were evaluated within 1-week for (reperfusion success, echocardiography for calculation of the ejection fraction (EF), arrhythmias, and mortality), and within 4-weeks for mortality.

RESULTS

 Within the tertile 3 of the HOMA-IR and TyG index, significant higher 4-week mortality (35% and 30%, respectively). Pearson correlation also showed significant and negative correlations between both HOMA-IR and TyG index values and EF. While reperfusion success, arrhythmias, and 1-week mortality did not correlate significantly with both HOMA-IR and TyG index.

CONCLUSION

 IR as defined by HOMA-IR and TyG index was significantly associated with poor outcomes in patients with acute STEMI in the form of EF<55 and 4-week mortality.

Impact of diabetes mellitus on all and successful percutaneous coronary intervention outcomes for chronic total occlusions: A systematic review and meta-analysis

BACKGROUND

Diabetes mellitus (DM) is a leading cause of morbidity and mortality globally and can affect numerous vital organs, including the kidney, liver, heart, nervous system, and vascular system.

OBJECTIVE

To assess the impact of type 2 diabetes mellitus (DM) on outcome in patients undergoing percutaneous coronary intervention (PCI) for chronic total occlusion (CTO).

METHODS

Academic databases were screened for eligible studies published prior to January 2021. Study quality was assessed using Cochrane's risk of bias tool and the Newcastle Ottawa scale.

RESULTS

Pooling studies that met inclusion criteria, we carried out a meta-analysis with a random-effects model and reported pooled odds ratios (ORs) with 95% confidence intervals (CIs). A total of ten studies featuring 8,276 participants met eligibility criteria. Type 2 DM patients had significantly higher odds of mortality (pooled OR: 1.62; 95% CI: 1.10 to 2.37), revascularization (pooled OR: 1.41; 95% CI: 1.14 to 1.74) and major adverse cardiac events (MACE) (pooled OR: 1.39; 95% CI: 1.18 to 1.63) relative to non-DM patients following PCI for CTO (regardless of PCI success or failure). Similarly, even when only looking at patients who underwent successful PCI, type 2 DM patients had significantly higher odds of revascularization (pooled OR: 1.54; 95% CI: 1.20 to 1.97) and MACE (pooled OR: 1.35; 95% CI: 1.13 to 1.63).

CONCLUSION

Type 2 DM significantly impacts the risk for adverse clinical outcomes even after successful PCI for CTO. As such, clinicians need to develop a comprehensive intervention package for DM patients with cardiovascular disease.

The predictive value of triglyceride-glucose index for in-hospital and one-year mortality in elderly non-diabetic patients with ST-segment elevation myocardial infarction

BACKGROUND

Triglyceride-glucose (TyG) index, a reliable marker of insulin resistance, was associated with cardiovascular morbidity and mortality. This study aimed to evaluate the predictive value of TyG index for mortality in elderly non-diabetic patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

In total, 430 non-diabetic patients aged over 65 years with STEMI were consecutively included. The TyG index was calculated by using the following formula: TyG index = ln (fasting triglyceride × fasting glucose/2). The 5-item modified frailty index score was utilized to determine comorbidities. Patients were divided into three groups based on TyG index tertiles.

RESULTS

Patients included into high TyG index tertile were male and had higher body mass index, glucose, triglyceride, low-density lipoprotein cholesterol, 5-item modified frailty index and GRACE risk score; and had low systolic blood pressure, estimated glomerular filtration rate and left ventricular ejection fraction. A one-unit increase in TyG index was associated with 3.03 extra cases per 1000 person-day for in-hospital mortality and 0.29 extra cases per 1000 person-day for long-term mortality. There was a non-linear relationship between TyG index and the risk of mortality with an increased risk above 8.5 for TyG index. Kaplan-Meier survival curves revealed that patients in high TyG index tertile had higher in-hospital and long-term mortality rates than those in low TyG index tertile.

CONCLUSIONS

This was the first study to demonstrate that the TyG index could predict in-hospital and long-term mortality in elderly non-diabetic STEMI patients.

Association of triglyceride-glucose index with prognosis of COVID-19: A population-based study

Background

Triglyceride-glucose (TyG) index is a simple and reliable surrogate marker for insulin resistance. Epidemiology studies have shown that insulin resistance is a risk factor for various infectious diseases. We evaluated the prognostic value of TyG index measured before the COVID-19 infection in COVID-19 infected patients.

Methods

From a nationwide COVID-19 cohort dataset in Korea, we included COVID-19 patients diagnosed between Jan and Jun 2020. Based on the nationwide health screening data between 2015 and 2018, TyG index was calculated as ln [triglyceride (mg/dL) × fasting glucose level (mg/dL)/2]. Primary outcome is development of severe complications of COVID-19 defined as composite of mechanical ventilation, intensive care unit care, high-flow oxygen therapy, and mortality within two months after the diagnosis of COVID-19.

Results

This study included 3887 patients with COVID-19 confirmed by reverse transcription polymerase chain reaction. Mean ± standard deviation of TyG index was 8.54 ± 0.61. Severe complications of COVID-19 were noted in 289 (7.44%) patients. In the multivariate logistic regression, TyG index was positively associated with severe complications of COVID-19 (adjusted odds ratio: 1.42, 95% confidence interval [1.12–1.79]).

Conclusions

In COVID-19 infected patients, high TyG index was associated with increased risk for severe complications. TyG index might be useful predictor for the severity of COVID-19 infection.

Vitamin D3 intake as modulator for the early biomarkers of myocardial tissue injury in diabetic hyperlipidaemic rats

CONTEXT

Myocardial cell death occurs within hours following the onset of myocardial ischaemia and its chief cause is atherosclerosis. There is a link between vitamin D3 deficiency and many cardiovascular risk factors.

OBJECTIVE

This study compared the effect of vitamin D3 on early biomarkers of myocardial injury, to that of atorvastatin.

METHODS

Diabetic hyperlipidaemia was induced in Wistar rats, which were divided into 3 groups: diabetic hyperlipidaemic control, diabetic hyperlipidaemic rats treated with atorvastatin and diabetic hyperlipidaemic rats treated with vitamin D3. Blood glucose, glycated haemoglobin and lipid profile were evaluated. Markers of myocardial injury were examined including cardiac troponin, heart fatty acid binding protein (HFABP) and C-terminal pro-endothelin-1 (CT-pro-ET-1).

RESULTS

Vitamin D3 and atorvastatin intake improved lipid profile and glucose homeostasis, and reduced levels of predictive biomarkers of myocardial injury.

CONCLUSION

Vitamin D3 can be used in a suitable dose as a safe and protective candidate against myocardial injury.

Outcomes Following Percutaneous Coronary Intervention in Saphenous Vein Grafts With and Without Embolic Protection Devices: A Systematic Review and Meta-Analysis

Objective

This study aimed to review studies comparing outcomes following percutaneous coronary intervention (PCI) in saphenous vein grafts (SVG) with and without embolic protection devices (EPD).

Methods

Databases including PubMed Central, Cochrane Library, EMBASE, CINAHL, MEDLINE, Google Scholar, ScienceDirect, and Scopus were searched from January 1964 to April 2021. We used the Cochrane risk of bias tool and the Newcastle Ottawa scale to assess the quality of published studies based on study design. From the results, we carried out a meta-analysis with a random-effects model and reported pooled odds ratio (OR) with 95% CI.

Results

In total, 11 studies were analyzed that included 79,009 total participants. EPD use had significantly lower odds of mortality (pooled OR = 0.69; 95% CI: 0.5–0.94). There was no significant difference in terms of major adverse cardiovascular events (MACE) (pooled OR = 0.83; 95% CI: 0.67–1.03), target vessel revascularization (pooled OR = 1; 95% CI: 0.95–1.05), periprocedural (pooled OR = 1.12; 95% CI: 0.65–1.9) and late myocardial infarction (MI) (pooled OR = 0.79; 95% CI: 0.55–1.14) with or without EPD for PCI in SVG patients.

Conclusion

Although not statistically beneficial for MACE, target vessel revascularization, periprocedural, and late MI, EPD use does appear to significantly reduce mortality for the patients undergoing PCI in SVG. Clinicians might consider using EPD for such patients to reduce the burden of post-procedural morbidity and mortality.

Visceral Adiposity Index Plays an Important Role in Prognostic Prediction in Patients With Non-ST-Segment Elevation Acute Coronary Syndrome and Type 2 Diabetes Mellitus Undergoing Percutaneous Coronary Intervention

Background: Visceral adiposity index (VAI), a surrogate marker of adiposity and insulin resistance, has been demonstrated to be significantly related to cardiovascular disease. It remains indistinct whether VAI predicts adverse prognosis after percutaneous coronary intervention (PCI) for patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) and type 2 diabetes mellitus (T2DM). Methods: A total of 798 participants who met the enrollment criteria were finally brought into this study. VAI was determined by waist circumference, body mass index, fasting triglyceride, and high-density lipoprotein cholesterol as previously reported. Adverse prognosis included all-cause death, non-fatal myocardial infarction, non-fatal ischemic stroke, and ischemia-driven revascularization, the composite of which was defined as the primary endpoint. Results: Higher VAI maintained as a significant and independent risk predictor for the primary endpoint, regardless of the adjustment for the various multivariate models [hazard ratio (95% CI) for fully adjusted model: 2.72 (2.02-3.68), p < 0.001]. The predictive value of VAI was further confirmed in sensitivity analysis where VAI was taken as a continuous variate. There was a dose-response relationship of VAI with the risk of the primary endpoint (p for overall association < 0.001). Moreover, the ability of VAI on the prediction of the primary endpoint was consistent between subgroups stratified by potential confounding factors (all p for interaction > 0.05). VAI exhibited a significant incremental effect on risk stratification for the primary endpoint beyond existing risk scores, expressed as increased Harrell's C-index, significant continuous net reclassification improvement, and significant integrated discrimination improvement. Conclusion: VAI is a significant indicator for predicting worse prognosis and plays an important role in risk stratification among patients with NSTE-ACS and T2DM undergoing elective PCI. The present findings require further large-scale, prospective studies to confirm.

Triglyceride-Glucose Index as a Surrogate Marker of Insulin Resistance for Predicting Cardiovascular Outcomes in Nondiabetic Patients with Non-ST-Segment Elevation Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention

AIM

The triglyceride-glucose index (TyG index) is proposed as a surrogate parameter for insulin resistance (IR) and, when elevated, is related to increased cardiovascular risks. Whether the TyG index is of great value in predicting adverse prognosis for individuals diagnosed with non-ST-segment elevation acute coronary syndrome (NSTE-ACS), who received elective percutaneous coronary intervention (PCI), and without recognized diabetes remains unclear.

METHODS

Overall, 1,510 subjects diagnosed with NSTE-ACS, who received elective PCI, and without recognized diabetes were enrolled in the current study. All participants received a routine follow-up after discharge. The TyG index was obtained from the following equation: napierian logarithmic (ln) [fasting triglyceride (TG, mg/dL)×fasting blood glucose (FBG, mg/dL)/2]. Adverse cardiovascular events included all-cause death, nonfatal myocardial infarction (MI), nonfatal ischemic stroke, and ischemia-driven revascularization, composite of which was defined as the primary endpoint.

RESULTS

Overall, 316 (20.9%) endpoint events were documented during a 48-month follow-up. Despite adjusting for confounding variates, the TyG index remains to be a significant risk predictor for the primary endpoint, with a hazard ratio (HR) [95% confidence interval (CI)] of 2.433 (1.853-3.196) (P＜0.001). A significant enhancement on the predictive performance for the primary endpoint emerged when adding the TyG index into a baseline model [area under the receiver-operating characteristic (ROC) curve (AUC), 0.835 for baseline model vs. 0.853 for baseline model＋TyG index, P＜0.001; net reclassification improvement (NRI), 0.194, P＜0.001; integrated discrimination improvement (IDI), 0.023, P=0.007].

CONCLUSIONS

The TyG index is an independent risk predictor for adverse cardiovascular events in nondiabetic subjects diagnosed with NSTE-ACS and who received elective PCI. Further prospective studies are needed to verify these findings.

Comparison of various insulin resistance surrogates on prognostic prediction and stratification following percutaneous coronary intervention in patients with and without type 2 diabetes mellitus

BACKGROUND

Insulin resistance (IR), evaluation of which is difficult and complex, is closely associated with cardiovascular disease. Recently, various IR surrogates have been proposed and proved to be highly correlated with IR assessed by the gold standard. It remains indistinct whether different IR surrogates perform equivalently on prognostic prediction and stratification following percutaneous coronary intervention (PCI) in non-ST-segment elevation acute coronary syndrome (NSTE-ACS) patients with and without type 2 diabetes mellitus (T2DM).

METHODS

The present study recruited patients who were diagnosed with NSTE-ACS and successfully underwent PCI. IR surrogates evaluated in the current study included triglyceride-glucose (TyG) index, visceral adiposity index, Chinese visceral adiposity index, lipid accumulation product, and triglyceride-to-high density lipoprotein cholesterol ratio, calculations of which were conformed to previous studies. The observational endpoint was defined as the major adverse cardiovascular and cerebrovascular events (MACCE), including cardiac death, non-fatal myocardial infarction, and non-fatal ischemic stroke.

RESULTS

2107 patients (60.02 ± 9.03 years, 28.0% female) were ultimately enrolled in the present study. A total of 187 (8.9%) MACCEs were documented during the 24-month follow-up. Despite regarding the lower median as reference [hazard ratio (HR) 3.805, 95% confidence interval (CI) 2.581-5.608, P < 0.001] or evaluating 1 normalized unit increase (HR 1.847, 95% CI 1.564-2.181, P < 0.001), the TyG index remained the strongest risk predictor for MACCE, independent of confounding factors. The TyG index showed the most powerful diagnostic value for MACCE with the highest area under the receiver operating characteristic curve of 0.715. The addition of the TyG index, compared with other IR surrogates, exhibited the maximum enhancement on risk stratification for MACCE on the basis of a baseline model (Harrell's C-index: 0.708 for baseline model vs. 0.758 for baseline model + TyG index, P < 0.001; continuous net reclassification improvement: 0.255, P < 0.001; integrated discrimination improvement: 0.033, P < 0.001). The results were consistent in subgroup analysis where similar analyses were performed in patients with and without T2DM, respectively.

CONCLUSION

The TyG index, which is most strongly associated with the risk of MACCE, can be served as the most valuable IR surrogate for risk prediction and stratification in NSTE-ACS patients receiving PCI, with and without T2DM.

High Triglyceride Glucose Index Is Associated with Poor Outcomes in Ischemic Stroke Patients after Reperfusion Therapy

INTRODUCTION

The triglyceride glucose index (TyG index) is a simple and reliable surrogate marker of insulin resistance (IR) that can predict functional outcomes and mortality after acute ischemic stroke (AIS). However, it is unclear whether the TyG index is associated with functional outcomes in patients with stroke who receive reperfusion therapy. Thus, we aimed to explore the prognostic value of the TyG index for the clinical outcomes of patients with AIS who underwent reperfusion therapy.

METHODS

We retrospectively assessed patients with AIS, with occlusion of either the middle cerebral artery or internal carotid artery, who were evaluated using multiphase computed tomography angiography (mCTA) and received reperfusion therapy. The TyG index was calculated as "ln [fasting glucose level (mg/dL) × triglyceride level (mg/dL)]/2." Collateral status was evaluated using mCTA based on the University of Calgary Scale. Clinical outcomes included 3-month functional outcomes, early neurological deterioration, recanalization status, and hemorrhagic transformation.

RESULTS

In all, 183 subjects (age 69.5 ± 12.4 years; men, 59.0%) were enrolled. The median initial National Institutes of Health Stroke Scale score was 15.0 (interquartile range [IQR] 11-18). The median TyG index was 4.8 (IQR, 4.6-5.1), and 158 patients had TyG levels >4.49, which represents the presence of IR. On univariate analysis, a higher TyG index was associated with both early neurological deterioration (18.4 vs. 0.0%, p = 0.041) and a 3-month poor functional outcome (mRS3-6) (61.4 vs. 32.0%, p = 0.011). After adjusting for multiple variables, including age, sex, type of reperfusion therapy, recanalization status, initial stroke severity, type of stroke, and history of hypertension and diabetes, high TyG index remained an independent predictor of a poor 3-month functional outcome (adjusted OR, 5.22; p = 0.014). However, TyG levels were not significantly associated with collateral status (p = 0.756).

CONCLUSIONS

IR, represented by a high TyG index, may predict poor 3-month functional outcomes in patients with AIS who undergo reperfusion therapy.

Impact of Acute Insulin Resistance on Myocardial Blush in Non-Diabetic Patients Undergoing Primary Percutaneous Coronary Intervention

Background: Myocardial blush grading is considered to be a novel tool for assessment of coronary microvasculature and myocardial perfusion in patients undergoing coronary angiography and angioplasty, and its reduction identifies patients at high risk. Our study aimed to evaluate the association between acute insulin resistance and myocardial blush in non-diabetic patients with ST-segment elevation myocardial infarction (STEMI). Methods: Two hundred forty non-diabetic patients with STEMI who underwent primary percutaneous coronary intervention were consecutively recruited. The relationship of homeostasis model assessment-estimated insulin resistance (HOMA-IR) to myocardial blush and in-hospital outcome was investigated. Results: Higher HOMA-IR tertile was observed in obese patients, with hyperinsulinemia, had Killip class >1, with higher CPK-MB level and was correlated to impaired myocardial blush after adjusting for the other confounding risk factors. It was also concluded that higher HOMA-IR was independently associated with no/minimal myocardial blush after STEMI. Moreover, it was founded to be an independent predictor of pulmonary edema and impaired left ventricular systolic function. Conclusion: This study revealed that acute insulin resistance was prevalent in non-diabetic patients with STEMI and was an independent predictor for post-infarction myocardial and microvascular injury and poor in-hospital outcome. Trial Registration: The trial was registered at the registry of Clinicaltrials.gov, ClinicalTrials.gov Identifier: NCT04651842, Date of registration: 2nd December 2020 Registry URL, https://clinicaltrials.gov/ct2/show/NCT04385589?cond=Dapagliflozin+in+diabetic+patients&cntry=EG&draw=2&rank=1.

Relationship between insulin resistance, coronary plaque, and clinical outcomes in patients with acute coronary syndromes: an analysis from the PROSPECT study

Background

We investigated the association of insulin resistance (IR) with coronary plaque morphology and the risk of cardiovascular events in patients enrolled in the Providing Regional Observations to Study Predictors of Events in Coronary Tree (PROSPECT) study.

Methods

Patients with acute coronary syndromes (ACS) were divided based on DM status. Non-DM patients were further stratified according to homeostasis-model-assessment IR (HOMA-IR) index as insulin sensitive (IS; HOMA-IR ≤ 2), likely-IR (LIR; 2 < HOMA-IR < 5), or diabetic-IR (DIR; HOMA-IR ≥ 5). Coronary plaque characteristics were investigated by intravascular ultrasound. The primary endpoint was major adverse cardiac events (MACE); a composite of cardiac death, cardiac arrest, myocardial infarction, and rehospitalization for unstable/progressive angina.

Results

Among non-diabetic patients, 109 patients (21.5%) were categorized as LIR, and 65 patients (12.8%) as DIR. Patients with DIR or DM had significantly higher rates of echolucent plaque compared with LIR and IS. In addition, DIR and DM were independently associated with increased risk of MACE compared with IS (adjusted hazard ratio [aHR] 2.29, 95% confidence interval [CI] 1.22–4.29, p = 0.01 and aHR 2.12, 95% CI 1.19–3.75, p = 0.009, respectively).

Conclusions

IR is common among patients with ACS. DM and advanced but not early stages of IR are independently associated with increased risk of adverse cardiovascular events.

Trial Registration ClinicalTrials.gov Identifier: NCT00180466.

Triglyceride glucose index for predicting cardiovascular outcomes after percutaneous coronary intervention in patients with type 2 diabetes mellitus and acute coronary syndrome

BACKGROUND

The triglyceride glucose (TyG) index, a simple surrogate estimate of insulin resistance, has been demonstrated to predict cardiovascular (CV) disease morbidity and mortality in the general population and many patient cohorts. However, to our knowledge, the prognostic usefulness of the TyG index after percutaneous coronary intervention (PCI) in patients with type 2 diabetes mellitus (T2DM) and acute coronary syndrome (ACS) has not been determined. This study aimed to evaluate the association of the TyG index with adverse CV outcomes in patients with T2DM and ACS who underwent PCI.

METHODS

The TyG index was calculated using the formula ln[fasting triglycerides (mg/dL) × fasting glucose (mg/dL)/2]. The primary endpoint was the composite of all-cause mortality, non-fatal stroke, non-fatal myocardial infarction, or unplanned repeat revascularization. The association between the TyG index and adverse CV outcomes was assessed by Cox proportional hazards regression analysis.

RESULTS

In total, 776 patients with T2DM and ACS who underwent PCI (mean age, 61 ± 10 years; men, 72.2%) were included in the final analysis. Over a median follow-up of 30 months, 188 patients (24.2%) had at least 1 primary endpoint event. The follow-up incidence of the primary endpoint rose with increasing TyG index tertiles. The multivariate Cox proportional hazards regression analysis adjusted for multiple confounders revealed a hazard ratio for the primary endpoint of 2.17 (95% CI 1.45-3.24; P for trend = 0.001) when the highest and lowest TyG index tertiles were compared.

CONCLUSIONS

The TyG index was significantly and positively associated with adverse CV outcomes, suggesting that the TyG index may be a valuable predictor of adverse CV outcomes after PCI in patients with T2DM and ACS.

Insulin resistance and dysglycemia are associated with left ventricular remodeling after myocardial infarction in non-diabetic patients

Background

Adverse cardiac remodeling after ST-segment elevation myocardial infarction (STEMI) is a major cause for poor cardiovascular outcomes such as heart failure. The predisposing factors and underlying mechanisms remain not fully understood. This study investigates the association of insulin resistance and dysglycemia with left ventricular (LV) remodeling after STEMI in non-diabetic patients.

Methods

A total of 485 non-diabetic subjects with STEMI who underwent primary percutaneous coronary intervention were consecutively enrolled and followed up for 12 months. Relation of homeostasis model assessment-estimated insulin resistance (HOMA-IR) and glucose levels to changes in echocardiography parameters was studied.

Results

Left ventricular dilation was detected in 49.1% of subjects at 12-month follow-up after STEMI, and was more severe in subjects with impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and high HOMA-IR levels. HOMA-IR remained correlated to changes in LV dimensions after adjusting for confounding risk factors. Multivariate regression analysis demonstrated that higher HOMA-IR was independently associated with greater LV dilation after STEMI. A significant interaction term was present between HOMA-IR and IGT in the model (P = 0.001).

Conclusions

Our study reveals that insulin resistance and dysglycemia are prevalent in non-diabetic patients with STEMI and are predictors of the post-infarction LV dilation.

Trial registration Trials number, NCT02089360; registered on March 17, 2014

Electronic supplementary material

The online version of this article (10.1186/s12933-019-0904-3) contains supplementary material, which is available to authorized users.

Association Between Insulin Resistance and Coronary Plaque Vulnerability in Patients With Acute Coronary Syndromes: Insights From Optical Coherence Tomography

We investigated the correlation between insulin resistance (IR) and optical coherence tomography and identified culprit plaque characteristics in patients with acute coronary syndrome (ACS). Patients with ACS who underwent selective coronary intervention were prospectively enrolled. A total of 159 culprit lesions were identified in 145 patients. Culprit plaque characteristics, including thin-cap fibroatheroma (TCFA) and spotty calcification, were analyzed. The IR was assessed using the homeostasis model assessment of IR (HOMA-IR). Patients were divided into 4 interquartile ranges (IQRs) according to HOMA-IR values. The prevalence rates of TCFA were significantly different among the 4 groups (17.5% [IQR1 group] vs 17.9% [IQR2 group] vs 35.0% [IQR3 group] vs 55.0% [IQR4 group]; P = .001). Minimal fibrous cap thickness was inversely correlated with HOMA-IR level (141.35 [56.28] µm vs 142.82 [82.17] µm vs 102.14 [36.52] µm vs 96.00 [41.82] µm; P < .001). Spotty calcification prevalence was also significantly different among the 4 groups (5.9% vs 17.6% vs 32.4% vs 44.1%; P < .001). Compared with the bottom quartile, patients with elevated HOMA-IR values had higher prevalence of macrophage infiltration ( P < .001) and microvessels ( P = .023). On multivariate analysis, Ln HOMA-IR (odds ratio: 6.022; 95% confidence interval: 3.007-12.060; P < .001) was the independent predictor for spotty calcification. The current study showed increased IR was independently associated with plaque vulnerability, spotty calcification in particular, in ACS.

Prognostic value of glucose metabolism for non-ST-segment elevation infarction patients with diabetes mellitus and single concomitant chronic total occlusion following primary percutaneous coronary intervention

Glucose metabolism status may play a predictive role in the severity of the complications among patients with type 2 diabetes mellitus (DM). However, few studies have focused on the prognostic value of glycosylated hemoglobin (HbA1c) and Homeostatic Model Assessment 2 for Insulin Resistance (HOMA2-IR) in patients with DM, non-ST-segment elevation infarction (NSTEMI), and single concomitant chronic total occlusion (CTO) following primary percutaneous coronary intervention (PCI). Short- and long-term prognostic value of HbA1c and HOMA2-IR in patients with DM with NSTEMI and single CTO who received primary percutaneous transluminal coronary intervention (pPCI).Data from 202 patients with NSTEMI and single CTO in nonculprit vessels were included. The incidence of revascularization, cardiogenic shock, ischemic stroke, major bleeding (ie, cerebral hemorrhage or massive hemorrhage of gastrointestinal tract), and cardiac death were combined as composite end points (CEPs). HbA1c was measured on admission and at 12 and 24 weeks after discharge. HOMA2-IR was measured on admission and at 6 and 12 weeks after discharge. The mean value of HbA1c and HOMA2-IR was calculated to determine the impact on 2.5-year CEPs. All patients were assessed during hospitalization and followed for up to 2.5 years after discharge.Mean age was 62.4 ± 11.8 years and 76% were male. Previous MI, lower left ventricular ejection fraction, and higher HbA1c (hazard ratio [HR] = 1.216; 95% confidence interval [CI] = 1.023-1.445; P = .023) were independently associated with a poor prognosis at 2.5 years. Higher HbA1c and HOMA2-IR on admission was associated with CEPs during hospitalization. Mean HOMA2-IR prior to pPCI was associated with revascularization (HR = 1.129; 95% CI = 1.008-1.265; P = .036) and ischemic stroke (HR = 1.276; 95% CI = 1.044-1.560; P = .017) during the 2.5 years follow-up period.Glucose metabolism status reflected by HbA1c and HOMA2-IR may provide prognostic value to patients with NSTEMI, type 2 DM, and single concomitant CTO following PCI. Therefore, patients with NSTEMI, CTO, and poor glycemic control should be carefully evaluated prior to PCI.

Dietary acid load and mortality among Japanese men and women: the Japan Public Health Center-based Prospective Study

Background: Diet-induced metabolic acidosis has been linked to cardiometabolic abnormalities including hypertension and type 2 diabetes. However, there are limited data on its association with other chronic diseases and mortality.Objective: The present study aimed to examine the association between dietary acid load and total and cause-specific mortality.Design: This study was a large-scale, population-based, prospective cohort study in Japan involving 42,736 men and 49,742 women, aged 45-75 y, who had no history of cancer, stroke, ischemic heart disease (IHD), or chronic liver disease at baseline. Dietary intake was assessed by using a validated 147-item food-frequency questionnaire. Potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores were derived from nutrient intake. Death and cause of death were identified by using the residential registry and death certificates. Cox proportional hazards regression was used to estimate HRs and 95% CIs for total and cause-specific mortality with adjustment for potential confounding variables.Results: During a median follow-up of 16.9 y, 12,993 total deaths occurred. A higher PRAL score was associated with higher total mortality: the multivariable-adjusted HR for total mortality for the highest compared with the lowest quartiles of PRAL scores was 1.13 (95% CI: 1.07, 1.18; P-trend < 0.001). This score was positively associated with mortality from cardiovascular disease (CVD) and particularly from IHD; the HRs (95% CIs) for the highest compared with the lowest quartile of PRAL score were 1.16 (1.06, 1.28) and 1.16 (1.02, 1.33) for CVD and IHD mortality, respectively. There was no association between PRAL score and cancer mortality. Similar associations were observed between NEAP score and total and cause-specific mortality.Conclusion: A high dietary acid load score was associated with a higher risk of total mortality and mortality from CVD, particularly from IHD, in Japanese adults.

Possible increase in insulin resistance and concealed glucose-coupled potassium-lowering mechanisms during acute coronary syndrome documented by covariance structure analysis

Objective

Although glucose-insulin-potassium (GIK) therapy ought to be beneficial for ischemic heart disease in general, variable outcomes in many clinical trials of GIK in acute coronary syndrome (ACS) had a controversial impact. This study was designed to examine whether “insulin resistance” is involved in ACS and to clarify other potential intrinsic compensatory mechanisms for GIK tolerance through highly statistical procedure.

Methods and results

We compared the degree of insulin resistance during ACS attack and remission phase after treatment in individual patients (n = 104). During ACS, homeostasis model assessment of insulin resistance (HOMA-IR) values were significantly increased (P<0.001), while serum potassium levels were transiently decreased (degree of which was indicated by ΔK) (P<0.001). This finding provides a renewed paradox, as ΔK, a surrogate marker of intrinsic GIK cascade activation, probably reflects the validated glucose metabolism during ischemic attack. Indeed, multiple regression analysis revealed that plasma glucose level during ACS was positively correlated with ΔK (P = 0.026), whereas HOMA-IR had no impact on ΔK. This positive correlation between ΔK and glucose was confirmed by covariance structure analysis with a strong impact (β: 0.398, P = 0.015). Intriguingly, a higher incidence of myocardial infarction relative to unstable angina pectoris, as well as a longer hospitalization period were observed in patients with larger ΔK, indicating that ΔK also reflects disease severity of ACS.

Conclusions

Insulin resistance most likely increases during ACS; however, ΔK was positively correlated with plasma glucose level, which overwhelmed insulin resistance condition. The present study with covariance structure analysis suggests that there are potential endogenous glucose-coupled potassium lowering mechanisms, other than insulin, regulating glucose metabolism during ACS.

Comparing the adverse clinical outcomes in patients with non-insulin treated type 2 diabetes mellitus and patients without type 2 diabetes mellitus following percutaneous coronary intervention: a systematic review and meta-analysis

Background

Several studies showed Type 2 Diabetes Mellitus (T2DM) to be associated with worse adverse clinical outcomes compared to non-T2DM (NDM) following Percutaneous Coronary Intervention (PCI). In addition, patients with insulin-treated T2DM (ITDM) showed worse clinical outcomes compared to patients with non-insulin treated T2DM (NITDM). Since NITDM and NDM have seldom been systematically analyzed, this study aimed to compare the short and long term adverse clinical outcomes observed in patients with NITDM and patients without T2DM following PCI.

Methods

Medline/PubMed, EMBASE and the Cochrane library were searched for Randomized Controlled Trials (RCTs) and observational studies comparing patients with (including ITDM and NITDM) and without T2DM following PCI. Endpoints included adverse clinical outcomes reported during a short and a long term follow up period. Odd Ratios (OR) and 95% Confidence Intervals (CI) in accordance with either a fixed or a random effects model appropriately, were calculated and the pooled analyses were performed with RevMan 5.3.

Results

Twelve studies consisting of a total number of 52,451 patients (14,863 NITDM and 37,588 NDM) were included. Patients with NITDM were found to have significantly higher short-term Major Adverse Cardiac Events (MACEs) and mortality with OR: 1.63, 95% CI (1.17, 2.27); P = 0.004 and OR: 1.71, 95% CI (1.40, 2.10), P < 0.00001 respectively and higher long-term MACEs and mortality with OR: 1.25, 95% CI (1.12, 1.40), P = 0.0001 and OR: 1.32, 95% CI (1.19, 1.47), P < 0.00001 respectively compared to NDM following PCI. In addition, compared to NDM, long-term Target Vessel Revascularization (TVR) and Target Lesion Revascularization (TLR) were significantly higher in the NITDM group with OR: 1.36, 95% CI (1.18, 1.56), P < 0.0001 and OR: 1.32, 95% CI (1.10, 1.59), P = 0.003 respectively. However, even if an increased long-term stent thrombosis was observed in the NITDM group with OR: 1.13; 95% CI (0.91, 1.40), P = 0.28, the result was insignificant.

Conclusion

Short and long term MACEs and mortality were significantly higher in patients with NITDM compared to patients without diabetes following PCI. Revascularization also significantly favored patients without T2DM. However, stent thrombosis was not significantly different.

Severely impaired microvascular reactivity in diabetic patients with an acute coronary syndrome

Background

Microvascular function is impaired in patients with stable coronary artery disease. The aim was to study microvascular function in patients with diabetes and acute coronary syndrome (ACS).

Methods

Microvascular function was evaluated in 83 patients by laser Doppler fluxmetry (LDF) [PU; perfusion unit, median (interquartile range)] measuring resting LDF and peak LDF following a six min heating of the skin to 44 °C at the foot, respectively. All patients with ACS and without previously known diabetes underwent oral glucose tolerance test. Thirty-nine patients with type 2 diabetes mellitus free from coronary artery disease served as controls.

Results

Peak LDF was significantly (P = 0.03) lower in patients with ACS and diabetes (n = 22; 72 (52)) and diabetes without coronary artery disease (n = 39; 69 (51)) as compared to patients with ACS without diabetes (n = 46; 97 (60)), and patients without ACS (n = 15; 140 (121)), respectively. Patients with ACS (n = 68) had significantly (P = 0.04) lower peak LDF (92 (49)) as compared to patients without ACS (n = 15) (140 (121)).

Conclusion

Microvascular reactivity is severely impaired in patients with diabetes and ACS. Diabetes has a major influence on microvascular function in patients with coronary artery disease.

Effect of Metformin Treatment on Lipoprotein Subfractions in Non-Diabetic Patients with Acute Myocardial Infarction: A Glycometabolic Intervention as Adjunct to Primary Coronary Intervention in ST Elevation Myocardial Infarction (GIPS-III) Trial

Objective

Metformin affects low density lipoprotein (LDL) and high density (HDL) subfractions in the context of impaired glucose tolerance, but its effects in the setting of acute myocardial infarction (MI) are unknown. We determined whether metformin administration affects lipoprotein subfractions 4 months after ST-segment elevation MI (STEMI). Second, we assessed associations of lipoprotein subfractions with left ventricular ejection fraction (LVEF) and infarct size 4 months after STEMI.

Methods

371 participants without known diabetes participating in the GIPS-III trial, a placebo controlled, double-blind randomized trial studying the effect of metformin (500 mg bid) during 4 months after primary percutaneous coronary intervention for STEMI were included of whom 317 completed follow-up (clinicaltrial.gov Identifier: NCT01217307). Lipoprotein subfractions were measured using nuclear magnetic resonance spectroscopy at presentation, 24 hours and 4 months after STEMI. (Apo)lipoprotein measures were obtained during acute STEMI and 4 months post-STEMI. LVEF and infarct size were measured by cardiac magnetic resonance imaging.

Results

Metformin treatment slightly decreased LDL cholesterol levels (adjusted P = 0.01), whereas apoB remained unchanged. Large LDL particles and LDL size were also decreased after metformin treatment (adjusted P<0.001). After adjustment for covariates, increased small HDL particles at 24 hours after STEMI predicted higher LVEF (P = 0.005). In addition, increased medium-sized VLDL particles at the same time point predicted a smaller infarct size (P<0.001).

Conclusion

LDL cholesterol and large LDL particles were decreased during 4 months treatment with metformin started early after MI. Higher small HDL and medium VLDL particle concentrations are associated with favorable LVEF and infarct size.

Adverse cardiovascular outcomes between insulin-treated and non-insulin treated diabetic patients after percutaneous coronary intervention: a systematic review and meta-analysis

BACKGROUND

Type 2 diabetes mellitus (DM) patients have worse adverse cardiovascular outcomes after Percutaneous Coronary Intervention (PCI). However, the adverse cardiovascular outcomes between insulin-treated and non-insulin treated DM patients have been a subject of debate. We sought to compare the short-term (<1 year) and long-term (≥1 year) cardiovascular outcomes between insulin-treated and non-insulin treated DM patients after PCI.

METHODS

Medline and Embase databases were searched for studies by typing 'diabetes and percutaneous coronary intervention/PCI' or 'insulin-treated and non-insulin treated diabetes mellitus and PCI'. Endpoints included adverse cardiovascular outcomes reported in these DM patients during the corresponding follow-up periods. Odd Ratio (OR) with 95% confidence interval (CI) was used to express the pooled effect on discontinuous variables and the pooled analyses were performed with RevMan 5.3.

RESULTS

21 studies have been included in this meta-analysis consisting of a total of 21,759 diabetic patients (6250 insulin-treated and 15,509 non-insulin treated DM patients). Short term mortality, myocardial infarction, target lesion revascularization, major adverse cardiac effects and, stent thrombosis were significantly higher in insulin-treated diabetic patients (OR 1.69, 95% CI 1.40-2.04, p < 0.00001), (OR 1.40, 95% CI 1.16-1.70, p = 0.0005), (OR 1.37, 95% CI 1.06-1.76, p = 0.02), (OR 1.46, 95% CI 1.22-1.76, p < 0.0001) and (OR 1.66, 95% CI 1.16-2.38, p = 0.005) respectively. Long-term cardiovascular outcomes were also significantly higher in insulin-treated DM patients.

CONCLUSION

Insulin treatment in these DM patients was associated with a significantly higher short and long-term adverse cardiovascular outcomes after PCI compared to those DM patients not treated by insulin therapy.

Association of insulin resistance and coronary artery remodeling: an intravascular ultrasound study

Background

There are few studies that investigated the correlation between insulin resistance (IR) and the coronary artery remodeling. The aim of the study is to investigate the association of IR measured by homeostasis model assessment of insulin resistance (HOMA-IR) and coronary artery remodeling evaluated by intravascular ultrasound (IVUS).

Methods

A total of 298 consecutive patients who received percutaneous coronary interventions under IVUS guidance were retrospectively enrolled. The value of HOMA-IR more than 2.5 was considered as IR positive. Metabolic syndrome was classified according to NCEP ATP III guidelines. The remodeling index was defined as the ratio of the external elastic membrane (EEM) area at the lesion site to the EEM area at the proximal reference site.

Results

A total of 369 lesions were analyzed (161 lesions in HOMA-IR positive and 208 lesions in HOMA-IR negative). Remodeling index was significantly higher in the HOMA-IR positive group compared with the negative group (HOMA-IR positive vs. negative: 1.074 ± 0.109 vs. 1.042 ± 0.131, p = 0.013). There was a significant positive correlation between remodeling index and HOMA-IR (p = 0.010). Analysis of HOMA-IR according to remodeling groups showed increasing tendency of HOMA-IR, and it was statistically significant (p = 0.045). Multivariate analysis revealed that only HOMA-IR was an independent predictor of remodeling index (r = 0.166, p = 0.018).

Conclusion

Increased IR estimated by HOMA-IR was significantly associated with a higher remodeling index and positive coronary artery remodeling.

Exercise training reduces insulin resistance in postmyocardial infarction rats

Myocardial infarction (MI) induces cardiac dysfunction and insulin resistance (IR). This study examines the effects of MI-related IR on vasorelaxation and its underlying mechanisms, with a specific focus on the role of exercise in reversing the impaired vasorelaxation. Adult male Sprague-Dawley rats were divided into three groups: Sham, MI, and MI+Exercise. MI+Exercise rats were subjected to 8 weeks of treadmill training. Cardiac contraction, myocardial and arterial structure, vasorelaxation, levels of inflammatory cytokines, expression of eNOS and TNF-α, and activation of PI3K/Akt/eNOS and p38 mitogen-activated protein kinase (p38 MAPK) were determined in aortas. MI significantly impaired endothelial structure and vasodilation (P < 0.05-0.01), as indicated by decreased arterial vasorelaxation to ACh and insulin. MI also attenuated the myocardial contractile response, decreased aortic PI3K/Akt/eNOS expression and phosphorylation by insulin, and increased IL-1β, IL-6, and TNF-α expression and p38 MAPK activity (P < 0.05-0.01). Exercise improved insulin sensitivity in aortas, facilitated myocardial contractile response and arterial vasorelaxation to ACh and insulin, and increased arterial PI3K/Akt/eNOS activity. Moreover, exercise markedly reversed increased p38 MAPK activity and normalized inflammatory cytokines in post-MI arteries. Inhibition of PI3K with LY-294002, and eNOS with L-NAME significantly blocked arterial vasorelaxation and PI3K/Akt/eNOS phosphorylation in response to insulin. In conclusion, these results demonstrate that endothelial dysfunction in response to insulin plays an important role in MI-related IR. The reversal of IR by exercise is most likely associated with normalizing inflammatory cytokines, increasing the activation of PI3K/Akt/eNOS, and reducing the activation of p38 MAPK.