Residual left ventricular pump function after acute myocardial infarction in NIDDM patients

The Effect of Diabetes Mellitus on Cardiac Remodeling and Overall Clinical Outcomes in Patients With Acute Myocardial Infarction: A Single-Center Retrospective Study in Saudi Arabia

BACKGROUND

Diabetes mellitus (DM) is a major chronic condition that is considered a strong indicator of poor cardiovascular outcomes, such as recurrent infarction and heart failure (HF), in individuals with acute myocardial infarction (AMI). However, the concept of left ventricular remodeling (LVR) following AMI in DM patients is not well understood and studied in Saudi Arabia. Thus, the aim of this study is to assess the association between LVR and DM in patients presenting with ST-elevation myocardial infarction (STEMI) who had reperfusion therapy with optimal medical therapy after percutaneous coronary intervention (PCI).

METHODS

In this retrospective cohort study, 171 patients diagnosed with AMI who visited King Faisal Cardiac Center in King Abdulaziz Medical City, National Guard Hospital, Jeddah, Saudi Arabia, were chosen via the convenience sampling method. The study included patients with AMI who received echocardiograms upon admission and during a follow-up period of six to 12 months. The patients were divided into two groups based on their diabetic status: diabetic (DM) and non-diabetic (non-DM). To collect the data, trained medical students supervised by the principal investigator used the patients' medical records.

RESULTS

The study showed that DM patients were more likely to have a history of hypertension, dyslipidemia, smoking, and stress hyperglycemia and had a higher hospitalization rate compared to the non-DM group. Although there was no statistically significant difference (p=0.253), both groups had a higher incidence of the left main trunk and/or left anterior descending artery affected. Regarding the echocardiographic finding, there were no significant differences between the two groups in terms of left ventricular ejection fraction, left ventricular internal diameter at end-diastole, left ventricular internal diameter at end-systole, and interventricular septum thickness.

CONCLUSION

This paper suggests that there is no significant correlation between DM and non-DM patients in terms of LVR after AMI. However, DM patients had a statistically significant increased risk of developing HF and valvular heart disease compared to non-DM patients after AMI.

Matrix Metalloproteinases and Their Role in Mechanisms Underlying Effects of Quercetin on Heart Function in Aged Zucker Diabetic Fatty Rats

Several mechanisms may contribute to cardiovascular pathology associated with diabetes, including dysregulation of matrix metalloproteinases (MMPs). Quercetin (QCT) is a substance with preventive effects in treatment of cardiovascular diseases and diabetes. The aim of the present study was to explore effects of chronic QCT administration on changes in heart function in aged lean and obese Zucker Diabetic Fatty (ZDF) rats and that in association with MMPs. Signaling underlying effects of diabetes and QCT were also investigated. In the study, we used one-year-old lean and obese ZDF rats treated for 6 weeks with QCT. Results showed that obesity worsened heart function and this was associated with MMP-2 upregulation, MMP-28 downregulation, and inhibition of superoxide dismutases (SODs). Treatment with QCT did not modulate diabetes-induced changes in heart function and MMPs. However, QCT activated Akt kinase and reversed effects of diabetes on SODs inhibition. In conclusion, worsened heart function due to obesity involved changes in MMP-2 and MMP-28 and attenuation of antioxidant defense by SOD. QCT did not have positive effects on improvement of heart function or modulation of MMPs. Nevertheless, its application mediated activation of adaptive responses against oxidative stress through Akt kinase and prevention of diabetes-induced negative effects on antioxidant defense by SODs.

Concurrent diabetes and heart failure: interplay and novel therapeutic approaches

Diabetes mellitus increases the risk of developing heart failure, and the co-existence of both diseases worsens cardiovascular outcomes, hospitalization and the progression of heart failure. Despite current advancements on therapeutic strategies to manage hyperglycemia, the likelihood of developing diabetes-induced heart failure is still significant, especially with the accelerating global prevalence of diabetes and an ageing population. This raises the likelihood of other contributing mechanisms beyond hyperglycemia in predisposing diabetic patients to cardiovascular disease risk. There has been considerable interest in understanding the alterations in cardiac structure and function in the diabetic patients, collectively termed as "diabetic cardiomyopathy". However, the factors that contribute to the development of diabetic cardiomyopathies is not fully understood. This review summarizes the main characteristics of diabetic cardiomyopathies, and the basic mechanisms that contribute to its occurrence. This includes perturbations in insulin resistance, fuel preference, reactive oxygen species generation, inflammation, cell death pathways, neurohormonal mechanisms, advanced glycated end-products accumulation, lipotoxicity, glucotoxicity, and posttranslational modifications in the heart of the diabetic. This review also discusses the impact of antihyperglycemic therapies on the development of heart failure, as well as how current heart failure therapies influence glycemic control in diabetic patients. We also highlight the current knowledge gaps in understanding how diabetes induces heart failure.

Macrovascular Complications of Type 2 Diabetes Mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) has emerged as a pandemic. It has different complications, both microvascular and macrovascular.

OBJECTIVE

The purpose of this review is to summarize the different types of macrovascular complications associated with T2DM.

METHODS

A comprehensive review of the literature was performed to identify clinical studies, which determine the macrovascular complications associated with T2DM.

RESULTS

Macrovascular complications of T2DM include coronary heart disease, cardiomyopathy, arrhythmias and sudden death, cerebrovascular disease and peripheral artery disease. Cardiovascular disease is the primary cause of death in diabetic patients. Many clinical studies have shown a connection between T2DM and vascular disease, but almost always other risk factors are present in diabetic patients, such as hypertension, obesity and dyslipidaemia.

CONCLUSION

T2DM causes a variety of macrovascular complications through different pathogenetic pathways that include hyperglycaemia and insulin resistance. The association between T2DM and cardiovascular disease is clear, but we need more clinical studies in order to identify the pure effect of T2DM.

Diabetic Cardiomyopathy: Does the Type of Diabetes Matter?

In recent years, type 2 diabetes mellitus has evolved as a rapidly increasing epidemic that parallels the increased prevalence of obesity and which markedly increases the risk of cardiovascular disease across the globe. While ischemic heart disease represents the major cause of death in diabetic subjects, diabetic cardiomyopathy (DC) summarizes adverse effects of diabetes mellitus on the heart that are independent of coronary artery disease (CAD) and hypertension. DC increases the risk of heart failure (HF) and may lead to both heart failure with preserved ejection fraction (HFpEF) and reduced ejection fraction (HFrEF). Numerous molecular mechanisms have been proposed to underlie DC that partially overlap with mechanisms believed to contribute to heart failure. Nevertheless, the existence of DC remains a topic of controversy, although the clinical relevance of DC is increasingly recognized by scientists and clinicians. In addition, relatively little attention has been attributed to the fact that both underlying mechanisms and clinical features of DC may be partially distinct in type 1 versus type 2 diabetes. In the following review, we will discuss clinical and preclinical literature on the existence of human DC in the context of the two different types of diabetes mellitus.

PPAR-γ receptor agonists-a review of their role in diabetic management in Trinidad and Tobago

The PPAR-γ receptor agonists, as a relatively new and perhaps still not very widely used class of antidiabetic agent in the Caribbean and particularly the Trinidadian context, possess pharmacologic properties that certainly have been shown to have impact on many of the inflammatory, metabolic, biochemical and structural macrovascular aberrations that occur in the type 2 diabetic. Activation of PPAR(gamma) nuclear receptors regulates the transcription of insulin-responsive genes involved in the control of glucose production, transport, and utilization. PPAR(gamma)-responsive genes also participate in the regulation of fatty acid metabolism, an important contributory pathogenic factor in this subset of patients. The unique mode of action of this class of therapeutic agent addresses a range of anomalies occurring at the cellular and sub-cellular level that are injurious to the diabetic. My aim in addressing the issue of the potential impact of PPAR-γ receptor agonists on cardiovascular disease (CVD) morbidity and mortality in the diabetic, is first, to seek to enhance both an awareness of, and greater familiarity among our own physicians, with this class of drug, and secondly, to effect a timely review of the recent literature as it relates to the tremendous possibilities for the potential clinical gains that might accrue from their use, in so far as this may serve to ameliorate the ravages of the CVD disease that all too tragically attends the type 2 diabetic, and more specifically those with the insulin resistance syndrome. (Mol Cell Biochem 263: 189-210, 2004).

MMP-9 signaling in the left ventricle following myocardial infarction

Following myocardial infarction (MI), the left ventricle (LV) undergoes a series of cardiac wound healing responses that involve both the stimulation of robust inflammation to clear necrotic myocytes and tissue debris and the induction of extracellular matrix (ECM) protein synthesis to generate an infarct scar. The collective changes in myocardial structure and function are termed LV remodeling, and matrix metalloproteinase-9 (MMP-9) is a key instigator of post-MI LV remodeling. Through direct molecular effects on ECM and inflammatory protein turnover as well as indirect effects on major cell types that coordinate cardiac wound healing, namely the infiltrating leukocytes and the cardiac fibroblasts, MMP-9 coordinates multiple aspects of LV remodeling. In this review, we will discuss recent research that has expanded our understanding of post-MI LV remodeling, including recent proteomic advances focused on the ECM compartment to provide novel functional and translational insights. This overview will summarize how our understanding of MMP-9 has evolved over the last decade and will provide insight into future directions that will drive our understanding of MMP-9-directed cardiac ECM turnover in the post-MI LV.

Comparison of quantity of left ventricular scarring and remodeling by magnetic resonance imaging in patients with versus without diabetes mellitus and with coronary artery disease

Diabetic patients with coronary artery disease (CAD) are more likely to develop heart failure (HF) than nondiabetic patients, but the mechanism responsible is unclear. Evidence suggests that infarct size and accompanying remodeling may not explain this difference. We used cardiac magnetic resonance (CMR) imaging to compare degree of left ventricular (LV) myocardial scar and remodeling in diabetic and nondiabetic patients with CAD. We evaluated 85 patients (39 diabetic, 46 nondiabetic) who underwent coronary angiography showing obstructive CAD and CMR imaging within 6 months of each other. Myocardial scar was measured by late gadolinium enhancement on CMR imaging and was graded according to spatial and transmural extents on a semiquantitative scale. More diabetic than nondiabetic patients had HF (69% vs 43%, p <0.03); however, groups did not differ in total scar burden (0.94 ± 0.60 vs 1.17 ± 0.74, p = NS), spatial extent of scar, or extent of transmural scar. Diabetes remained an independent predictor of HF after adjustment for CAD and other variables. LV ejection fraction (36 ± 12% vs 37 ± 14%, p = NS) and end-diastolic volume (215 ± 56 vs 217 ± 76 ml, p = NS) were similar for diabetic and nondiabetic patients, respectively. In conclusion, although diabetic patients with CAD had a higher prevalence of HF than nondiabetic patients, there was no difference in myocardial scar, LV volume, or LV ejection fraction. These findings support the theory that mechanisms other than extent of myocardial injury and negative remodeling play a significant role in the development of HF in diabetic patients with CAD.

[Link between diabetes and diastolic dysfunction and the diagnostic role of echocardiography]

Diabetes mellitus, a disease that has been reaching epidemic proportions, is an important risk factor to the development of cardiovascular complication. The left ventricular diastolic dysfunction represents the earliest pre-clinical manifestation of diabetic cardiomyopathy, preceding systolic dysfunction and being able to evolve to symptomatic heart failure. In early stages, these changes appear reversible with tight metabolic control, but as pathologic processes become organized, the changes are irreversible and contribute to an excess risk of heart failure among diabetic patients. Doppler echocardiography provides reliable data in the stages of diastolic function, as well as for systolic function. Combination of pulsed tissue Doppler study of mitral annulus with transmitral inflow may be clinically valuable for obtaining information about left ventricular filling pressure and unmasking Doppler inflow pseudonormal pattern, a hinge point for the progression toward advanced heart failure. Subsequently we give an overview about diabetes and its complications, their clinical relevance and the role of echocardiography in detection of diastolic heart failure in diabetes.

Infarct size, ejection fraction, and mortality in diabetic patients with acute myocardial infarction treated with thrombolytic therapy

BACKGROUND

Diabetic patients with acute myocardial infarction (MI) have higher mortality than nondiabetic patients. The purpose of this study was to examine if larger infarct size explains the higher mortality in diabetic patients with acute ST-segment-elevation MI.

METHODS

In the CORE trial (n = 2948), subsets of patients underwent quantitative radionuclide measurement of technetium Tc 99m sestamibi infarct size (n = 1164) or gated equilibrium left ventricular ejection fraction (LVEF) (n = 1137) at days 6 to 16 after thrombolytic therapy. Clinical follow-up was 96.7% complete at 6 months.

RESULTS

The prevalence of diabetes in these patient imaging subsets was 16% to 17%. Higher risk clinical characteristics including older age and a greater prevalence of prior MI were more common in diabetic patients. Median infarct size was larger in diabetic patients (22% vs 17% of the left ventricle, P = .04), a difference that remained significant after adjustment for clinical variables (P = .048). Patients with diabetes also had lower median LVEF (48% vs 51%, unadjusted P = .002, adjusted P = .007). Six-month mortality was higher in diabetic patients: infarct size subset, 5.9% vs 1.6% (P = .0016); LVEF subset, 6.1% vs 1.0% (P < .0001). Multivariable models demonstrated that diabetes and each imaging variable were independent predictors of mortality.

CONCLUSIONS

Infarct size is modestly larger and LVEF modestly lower in diabetic patients with ST-segment-elevation MI. The substantially higher (4- to 6-fold) mortality rate in diabetic vs nondiabetic patients is only partially explained by relatively small differences in infarct size and LVEF.

The impact of admission plasma glucose on long-term mortality after STEMI and NSTEMI myocardial infarction

Diabetes mellitus is a widely recognized risk factor for cardiovascular disease. Type 2 diabetics have a 3-fold increased risk of CAD; prediabetics, without chronic hyperglycemia, have a 2-fold increased risk compared with normal subjects. We determined in 615 consecutive acute infarction patients whether the admission plasma glucose level remains associated with major adverse cardiovascular events (MACE) in an unselected patient population with myocardial infarction. Of these, the mean age of 66+/-12 years (range 36-90) and 69% were men and mean APG and HbA1c level were 8.2+/-4.0 mmol/l and 6.1+/-1.1% respectively. 13.2% of total study population was already known with diabetes. We recorded 132 deaths (21.5%), of whom 23.6% were known diabetic patients during 2.5 years of follow-up Multivariate statistical analysis identified APG, older age and previous MI as independent mortality predictors.

CONCLUSION

Increased APG levels are significantly and independently correlated with poor prognosis after myocardial infarction, and this underlines the need for better medical treatment of hyperglycemic state and aggressive screening for early detection of diabetes.

Diabetes mellitus impairs myocardial oxygen metabolism even in non-infarct-related areas in patients with acute myocardial infarction

BACKGROUND

Although diabetes is associated with poor clinical outcomes after acute myocardial infarction, to date there have been no reports focusing on the myocardial oxygen metabolism in these patients. Thus, we evaluated the myocardial oxygen metabolism in patients with and without diabetes suffering from acute myocardial infarction using carbon-11 acetate positron emission tomography.

METHODS

20 patients (13 diabetic patients [group A] and 7 non-diabetic patients [group B]) underwent carbon-11 acetate positron emission tomography soon after the onset of acute myocardial infarction. The myocardial oxygen metabolism was evaluated within the infarct-related area and in the non infarct-related area. 6 healthy volunteers (group C) and 6 diabetic patients without coronary artery disease (group D) also participated as controls.

RESULTS

There were no significant differences in gender, age, infarct-related artery, peak level of serum creatine phosphokinase, left-ventricular ejection fraction at onset, or the defect severity on myocardial perfusion images between group A and group B. In group A, the clearance rate (Kmono) of carbon-11 acetate in infarct-related area (0.042+/-0.010) was not significantly different from that in group B (0.049+/-0.016). In contrast, Kmono in non infarct-related area in group A (0.059+/-0.010) was significantly lower than that in group B (0.076+/-0.009; p=0.002), group C (0.072+/-0.004; p=0.026) and group D (0.078+/-0.005; p=0.001).

CONCLUSIONS

These data indicate that the myocardial oxygen metabolism even in non infarct-related area in diabetic patients was impaired after the onset of acute myocardial infarction.

Clinical outcomes and left ventricular function in diabetic patients with acute myocardial infarction treated by primary coronary angioplasty

The objective of the present study was to compare left ventricular (LV) function and clinical outcomes in diabetics versus nondiabetics with acute myocardial infarction (AMI) treated by primary coronary angioplasty. A total of 327 consecutive AMI subjects were reperfused by primary coronary angioplasty within 12 hours from onset. Diabetes mellitus (DM) was present in 104 of the 327 patients. LV function was serially determined by left ventriculograms taken in the acute and chronic phases (6 months after onset). (I) The early ST-segment resolution rate was lower in DM patients compared with non-DM patients (59% versus 83%, P < 0.0001). (II) During a 6-month follow-up, the percentages of target vessel revascularization (TVR), coronary aorta bypass grafting (CABG), and cardiac death were higher in the DM patients compared with the non-DM patients (TVR: 29% versus 19%; P < 0.05, CABG: 10% versus 5% ; P < 0.05, cardiac death: 12% versus 4%; P = 0.01). (III) The differences in left ventricular ejection fraction (LVEF) between two stages (delta-LVEF) were significantly lower in the DM patients than the non-DM patients (1 +/- 9% versus 7 +/- 10%, P < 0.0001). (IV) Multivariate analysis identified DM as an independent predictor of cardiac death (Odds ratio 5.5, 95% CI, 1.3-23.7, P < 0.05) and as a sole independent predictor of LVEF deterioration (Odds ratio 5.8, 95% CI, 2.8-11.8, P < 0.001). In patients with AMI treated using primary coronary angioplasty, DM is closely related to left-ventricular systolic dysfunction and a poor patient outcome, including mortality.

Intensive insulin therapy does not alter the inflammatory response in patients undergoing coronary artery bypass grafting: a randomized controlled trial [ISRCTN95608630]

INTRODUCTION

Strict control of plasma glucose in diabetic and non-diabetic patients has been shown to improve outcome in several clinical settings. There is extensive evidence that glucose can stimulate the production of pro-inflammatory cytokines such as tumor necrosis factor (TNF)-alpha and IL-6, with no effect on the anti-inflammatory cytokine IL-10. We hypothesized that strict glucose regulation results in a change in cytokine balance from a pro-inflammatory state to a more balanced anti-inflammatory condition. In a randomized controlled trial we studied the effect of strict glycemic control on the local and systemic pro-inflammatory and anti-inflammatory balance in non-diabetic patients undergoing elective coronary artery bypass grafting with cardiopulmonary bypass.

METHODS

After surgery patients were randomly assigned to intensive insulin therapy (blood glucose between 80 and 110 mg/dl) or conventional insulin therapy (blood glucose less than 200 mg/dl). At 0, 1, 2, 4, 8, 12, 16 and 24 hours after admission to the intensive care unit, plasma samples and samples from the mediastinal drains were obtained. We measured the concentrations of the pro-inflammatory cytokines TNF-alpha and IL-6 and the anti-inflammatory cytokine IL-10 by enzyme-linked immunosorbent assay.

RESULTS

Both patient groups were comparable in demographics, clinical characteristics and peri-operative data. In the intensive treatment group, glucose levels were significantly lower than in the conventionally treated group. No differences were found between both groups in the concentrations of TNF-alpha, IL-6 and IL-10 in plasma samples or in fluid draining the mediastinal cavity. Levels of IL-6 and IL-10 were significantly higher in mediastinal fluid samples than in plasma samples, suggesting a compartmentalized production of cytokines.

CONCLUSION

The protective effect of intensive insulin therapy in patients after cardiac surgery with cardiopulmonary bypass is not related to a change in cytokine balance from a pro-inflammatory to an anti-inflammatory pattern. Systemic cytokine levels are not representative of the local inflammatory response.

Clinical features, triage, and outcome of patients presenting to the ED with suspected acute coronary syndromes but without pain: a multicenter study

We studied the impact on triage and outcome of patients presenting to the emergency department (ED) with symptoms suggestive of an acute coronary syndromes (ACS) but without a complaint of pain. Data from a prospective clinical trial of patients with symptoms suggesting an ACS in the EDs of 10 US hospitals comparing patient demographics, clinical variables, and outcomes was used to perform a secondary analysis. Of 10,783 subjects, a final diagnosis of an ACS was confirmed in 24% of which 35% had acute myocardial infarction (AMI) and 65% unstable angina pectoris (UAP). Pain was absent in 6.2% of patients with acute ischemia and in 9.8% of those with AMI. Compared to similar patients who presented with pain, patients with painless ischemia were older, were more commonly women, had more cardiac and related diseases. Among patients with AMI, fewer patients without pain were admitted to critical care units compared to similar patients with pain. Among patients with AMI, logistic regression predicting lack of pain identified age, heart failure and diabetes, with only age and heart failure among all with ACS. After controlling for clinical features, lack of pain during acute ischemia predicted increased hospital mortality. We concluded that age and heart failure are independently associated with painless ACS, in addition to diabetes among those with AMI. Lack of pain predicts increased hospital mortality in patients with ACI through mechanisms that remain to be elucidated. There is a need for greater awareness in the general public of the different manifestations of ACS to enhance the recognition of and prompt response to their symptoms.

Rosiglitazone treatment in Zucker diabetic Fatty rats is associated with ameliorated cardiac insulin resistance and protection from ischemia/reperfusion-induced myocardial injury

The mechanism responsible for the enhanced myocardial susceptibility to ischemic insult in patients with type 2 diabetes is not clear. The present study examines the effect of rosiglitazone treatment on cardiac insulin sensitization and its association with cardioprotection from ischemia/reperfusion injury in an animal model of diabetes. Male Zucker diabetic fatty (ZDF) rats were treated with rosiglitazone (3 mg . kg(-1) . day(-1) orally) or vehicle for 8 days before undergoing 30 min of coronary artery ligation, followed by reperfusion for 4 h (apoptosis) or 24 h (infarction). Rosiglitazone reduced the blood levels of glucose, triglycerides, and free fatty acids; enhanced cardiac glucose oxidation; and increased Akt phosphorylation (Akt-pS473) 2.1-fold and Akt kinase activity 1.8-fold in the ischemic myocardium. The phosphorylation of two downstream targets of Akt, glycogen synthase kinase-3beta and FKHR (forkhead transcription factor), was also enhanced by 2- and 2.9-fold, respectively. In rosiglitazone-treated rats, the number of apoptotic cardiomyocytes and the myocardial infarct size were decreased by 58 and 46%, respectively, and the myocardial contractile dysfunction was improved. Blockade of the insulin-Akt signaling pathway by wortmannin in the 8-day rosiglitazone-treated ZDF rats resulted in a markedly diminished cardioprotective effect of rosiglitazone. In addition, 8-day rosiglitazone treatment in Zucker lean rats or 2-day rosiglitazone treatment in ZDF rats, both of which showed no change in whole-body insulin sensitivity, resulted in a significant reduction in cardiac infarct size, but to a lesser degree when compared with that observed in 8-day rosiglitazone-treated ZDF rats. These results suggest that chronic treatment with rosiglitazone protects the heart against ischemia/reperfusion injury in ZDF rats, and that the enhanced cardiac protection observed after rosiglitazone treatment might be attributable in part to an improvement in cardiac insulin sensitivity.

Left ventricular remodeling and heart failure in diabetic patients treated with primary angioplasty for acute myocardial infarction

BACKGROUND

Diabetes mellitus has been recognized as a strong predictor of heart failure (HF) in patients with acute myocardial infarction (AMI). However, considerable controversy exists regarding the pathogenetic mechanisms of HF after AMI in diabetic patients. We hypothesized that the increased incidence of HF in diabetic patients was associated with a greater propensity for left ventricular (LV) remodeling.

METHODS AND RESULTS

A series of 325 patients (42 diabetics) with AMI successfully treated with primary angioplasty underwent serial 2D echocardiography from admission to 1 and 6 months and 6-month angiography. No significant difference was found between diabetics and nondiabetics regarding baseline clinical, angiographic, and echocardiographic characteristics, as well as 6-month restenosis and reocclusion rates. At 6 months, a similar incidence of LV remodeling was observed in diabetics and nondiabetics (33% versus 25%; P=0.234), with similar patterns of changes in LV volumes and LV global and regional systolic function. At 5 years, the incidence of HF was higher in the diabetics (43% versus 20%, P=0.001). Diabetes was found to be an independent predictor of HF at 5 years (hazard ratio, 1.8; P=0.0366). However, LV remodeling was predictive of HF in the nondiabetics (P=0.023) but not in the diabetics (P=0.123). In a subgroup of patients, higher LV chamber stiffness (as assessed by echocardiography) was detected in the diabetics with HF.

CONCLUSIONS

The more frequent progression to HF in the diabetics after AMI is not explained by a greater propensity for LV remodeling. Other factors, such as diastolic dysfunction, may play a role.

Effects of trimetazidine on left ventricular function in patients with type 2 diabetes and heart failure

Congestive heart failure and type 2 diabetes have a deleterious prognosis when combined. Trimetazidine, a metabolic agent with anti-ischemic properties, reduces fatty acid beta-oxidation via decreased 3-ketoacyl-coenzyme-A thiolase activity thereby facilitating energy production via the glycolytic pathway.

OBJECTIVES

To assess myocardial function by Tissue Doppler Imaging (TDI) after one month of trimetazidine (Vastarel) added-on conventional treatment in patients with type 2 diabetes and heart failure.

METHODS

Twenty diabetic patients with ischemic heart failure (mean age 66 years; NYHA class II-III) were randomized to trimetazidine (60 mg daily) or placebo in a double-blind crossover design. Exercise tolerance, 2-dimensional echocardiograms, and TDI (rest and exercise) were studied before and during treatment.

RESULTS

Changes in exercise tolerance did not differ in the two groups. Ejection fraction at rest and moderate exercise only improved significantly with trimetazidine when analyzed for the first treatment period. TDI velocities did not change significantly during treatment periods.

CONCLUSION

In this early pilot investigation of the effects of trimetazidine in patients with diabetes and heart failure there were only weak signs of improved systolic myocardial function at rest and exercise. The present observations indicate the need of further research to explore the effect of trimetazidine during longer treatment period or with more selected patient population.

Prognostic relations between inflammatory markers and mortality in diabetic patients with non-ST elevation acute coronary syndrome

OBJECTIVE

To determine the differences in the inflammatory status between diabetic and non-diabetic patients and to evaluate the usefulness of C reactive protein, fibrinogen, and leucocyte count as predictors of death in diabetic patients with unstable coronary disease.

DESIGN

Nested case-control comparisons of the inflammatory status between diabetic and non-diabetic patients. Prospective cohort analysis of C reactive protein concentration, fibrinogen concentration, and leucocyte count as predictors of cardiovascular death in diabetic patients.

SETTING

Coronary care unit in Spain.

PARTICIPANTS

83 diabetic patients with non-ST elevation acute coronary syndrome and 83 sex and aged matched patients selected from 361 non-diabetic patients with non-ST elevation acute coronary syndrome.

MAIN OUTCOME MEASURES

Plasma concentrations of C reactive protein and fibrinogen, and leucocyte count. Investigators contacted patients to assess clinical events.

RESULTS

Concentrations of C reactive protein and fibrinogen, and leucocyte count on admission were higher in diabetic than in non-diabetic patients (7 mg/l v 5 mg/l, p = 0.020; 3.34 g/l v 2.90 g/l, p = 0.013; and 8.8 x 10(9)/l v 7.8 x 10(9)/l, p = 0.040). Among diabetic patients, these values were also higher in those who died during the 22 month follow up (13 mg/l v 6 mg/l, p = 0.001; 3.95 g/l v 3.05 g/l, p < 0.001; and 11.4 x 10(9)/l v 8.4 x 10(9)/l, p = 0.005). After adjustment for confounding factors, diabetic patients in the highest tertile of C reactive protein had a hazard ratio for cardiovascular death of 4.51 (95% confidence interval (CI) 1.62 to 12.55). Similar hazard ratios were for fibrinogen 3.74 (95% CI 1.32 to 10.62) and for leucocyte count 3.64 (95% CI 1.37 to 9.68).

CONCLUSIONS

Inflammation appears more evident in diabetic than in non-diabetic patients with acute coronary syndrome. C reactive protein concentration, fibrinogen concentration, and leucocyte count constitute independent predictors of cardiovascular death in diabetics with unstable coronary disease.

Effects of the early ACE inhibition in diabetic nonthrombolyzed patients with anterior acute myocardial infarction

OBJECTIVE

The aim of the present study was to evaluate the clinical efficacy of the ACE inhibitor zofenopril in a cohort of diabetic patients with nonthrombolyzed anterior acute myocardial infarction who were enrolled in the Survival of Myocardial Infarction Long-Term Evaluation (SMILE) trial.

RESEARCH DESIGN AND METHODS

Among the overall population of 1,512 patients, 303 (20.0%) had diabetes. The primary end point of this study was the effect of treatment on the 6-week combined occurrence of death and severe congestive heart failure (CHF). Secondary end points included the evaluation of the 6-week rate of major cardiovascular events as well as the 1-year survival rate.

RESULTS

After 6 weeks of double-blind treatment, zofenopril significantly reduced both the incidence of the primary end point (8.6 vs. 18.3%; P = 0.019) and the 6-week incidence of severe CHF (0 vs. 7.3%; P = 0.001) in diabetic patients, and the effect was greater than that observed in nondiabetic patients. Conversely, 1-year mortality was significantly reduced among nondiabetic patients (9.1 vs. 13.8%; P = 0.010), whereas in the diabetic population, the decrease did not reach statistical significance (13.7 vs. 16.5%; P = 0.52).

CONCLUSIONS

The present data suggest that the clinical outcome of patients with diabetes and myocardial infarction can be significantly improved by early treatment with zofenopril. The lesser effect on 1-year mortality seems to suggest that long-term treatment is probably needed to maintain the benefits of the early ACE inhibition in patients with diabetes.

Influence of diabetes mellitus on heart failure risk and outcome

Our aim is to summarize and discuss the recent literature linking diabetes mellitus with heart failure, and to address the issue of the optimal treatment for diabetic patients with heart failure. THE STUDIES LINKING DIABETES MELLITUS (DM) WITH HEART FAILURE (HF) : The prevalence of diabetes mellitus in heart failure populations is close to 20% compared with 4 to 6% in control populations. Epidemiological studies have demonstrated an increased risk of heart failure in diabetics; moreover, in diabetic populations, poor glycemic control has been associated with an increased risk of heart failure. Various mechanisms may link diabetes mellitus to heart failure: firstly, associated comorbidities such as hypertension may play a role; secondly, diabetes accelerates the development of coronary atherosclerosis; thirdly, experimental and clinical studies support the existence of a specific diabetic cardiomyopathy related to microangiopathy, metabolic factors or myocardial fibrosis. Subgroup analyses of randomized trials demonstrate that diabetes is also an important prognostic factor in heart failure. In addition, it has been suggested that the deleterious impact of diabetes may be especially marked in patients with ischemic cardiomyopathy. TREATMENT OF HEART FAILURE IN DIABETIC PATIENTS : The knowledge of the diabetic status may help to define the optimal therapeutic strategy for heart failure patients. Cornerstone treatments such as ACE inhibitors or beta-blockers appear to be uniformly beneficial in diabetic and non diabetic populations. However, in ischemic cardiomyopathy, the choice of the revascularization technique may differ according to diabetic status. Finally, clinical studies are needed to determine whether improved metabolic control might favorably influence the outcome of diabetic heart failure patients.

Ventricular remodeling does not accompany the development of heart failure in diabetic patients after myocardial infarction

BACKGROUND

Diabetic patients are at increased risk for heart failure (HF) and other adverse events after myocardial infarction (MI). Left ventricular (LV) enlargement after MI is also associated with the same increased risk. We used data from the Survival and Ventricular Enlargement (SAVE) echocardiographic substudy to test the hypothesis that diabetes was associated with increased LV enlargement after MI.

METHODS AND RESULTS

Four hundred twelve nondiabetic and 100 diabetic patients underwent echocardiographic assessment at baseline and 3 months, 1 year, and 2 years after MI. HF developed in 30% of diabetic and 17% of nondiabetic patients during follow-up (P<0.001). Baseline LV diastolic size, ejection fraction, and infarct segment length were similar between diabetic and nondiabetic patients. Diabetic patients demonstrated less LV enlargement between baseline and 2 years than nondiabetic patients (0.9+/-11.1 cm2 versus 3.8+/-10.9 cm2, P=0.047). In patients who developed HF, LV diastolic dilatation (10.0+/-12.4 cm2 versus 3.7+/-13.1 cm2, P=0.06) and systolic dilatation (4.6+/-11.8 versus 0.91+/-12.1, P=0.017) were greater in nondiabetic than in diabetic patients. LV dilatation between baseline and 2 years was a predictor of HF in nondiabetic patients, but not in diabetic patients, even after excluding patients with recurrent MI and adjusting for history of hypertension, prior MI, age, treatment group, and smoking. Diabetes modified the relationship between ventricular enlargement and the risk of HF (P=0.011).

CONCLUSIONS

The increased incidence of HF after MI in diabetic patients is not explained by a greater propensity for LV remodeling.

Impaired glucose metabolism predicts mortality after a myocardial infarction

Diabetes is a risk factor for increased mortality after a myocardial infarction. Whether this applies for patients with hyperglycemia during the acute phase of a acute myocardial infarction is unclear. Therefore we determined the relation between admission plasma glucose level and mortality in a prospectively collected series of 336 consecutive AMI patients. Patients were divided in four groups based on WHO criteria for glucose levels: I: <5.6 mmol/l, II: 5.6--8.3 mmol/l, III: 8.4--11.0 mmol/l, IV: 11.1 mmol/l. The average age was 68+/-11 years with a peak CK of 1378+/-160 U/l, 34% were anterior wall AMIs and 52% were treated with thrombolysis. All patients had a long-term follow-up control at an average of 14.2 months. One year mortality rate was 19.3% and rose to 44% in patients with glucose levels >11.1 mmol/l. The mortality was higher in diabetic patients than in non-diabetic patients (40 vs. 16%; P<0.05). Multivariate analysis revealed an independent effect of glucose level on mortality. In conclusions, our study in an unselected patient population demonstrates that admission plasma glucose level independently predicts 1 year mortality even in absence of diagnosed diabetes mellitus. Further studies evaluating the effect of acute insulin intervention in reducing mortality are warranted.

Effect of diabetes mellitus and insulin use on survival after acute myocardial infarction in the elderly (the Cooperative Cardiovascular Project)

Using data from a retrospective cohort study of Medicare beneficiaries hospitalized with an acute myocardial infarction (AMI), we evaluated the role of diabetes mellitus on 30-day and 1-year mortality. We classified subjects as nondiabetics, diabetics controlled with diet alone, diabetics receiving an oral hypoglycemic agent, and diabetics on insulin at time of admission. We compared baseline admission characteristics of subgroups using chi-square and Wilcoxon rank-sum tests and evaluated the effect of each diabetic state using sequential logistic models. We identified 80,832 nondiabetic patients, 9,862 diet-controlled diabetic patients, 14,664 diabetics receiving an oral hypoglycemic agent, and 12,241 diabetic patients on insulin therapy. Although mean age was similar among the groups, prevalence of hypertension, prior AMI, prior congestive heart failure, and prior revascularization were higher among diabetic patients, particularly those taking insulin. Diabetic patients, particularly those taking insulin, were less likely to receive aspirin and beta blockers and to undergo coronary revascularization. Diabetic patients had higher 30-day and 1-year mortality than nondiabetic patients. After adjustment for demographics, clinical and hospital characteristics, and treatment strategies, insulin-treated diabetics had the highest risk of mortality, followed by diabetics receiving oral hypoglycemic agents, followed by diet-controlled diabetics. Thus, diabetes is highly prevalent among elderly patients with an AMI. Mortality rates for these patients, particularly insulin-using diabetics, are higher than among their nondiabetic counterparts. Preventive and therapeutic strategies must be developed to ensure improved short- and long-term outcomes for elderly patients with diabetes and AMI.

Effect of the angiotensin-converting enzyme inhibitor trandolapril on mortality and morbidity in diabetic patients with left ventricular dysfunction after acute myocardial infarction. Trace Study Group

OBJECTIVES

This study evaluated the efficacy of long-term treatment with the angiotensin-converting enzyme (ACE) inhibitor trandolapril in diabetic patients with left ventricular dysfunction after acute myocardial infarction (AMI).

BACKGROUND

Patients with diabetes mellitus have a high mortality following AMI, probably due to a high risk of congestive heart failure and reinfarction. Because ACE inhibition effectively reduces progression of heart failure, it could be particularly beneficial in diabetic patients after AMI.

METHODS

The study is a retrospective analysis using data from the Trandolapril Cardiac Evaluation (TRACE) study, which was a randomized, double-blind, placebo-controlled trial of trandolapril in 1,749 patients with AMI and ejection fraction < or =35%. The mean follow-up time was 26 months.

RESULTS

A history of diabetes was found in 237 (14%) of the 1,749 patients. Treatment with trandolapril resulted in a relative risk (RR) of death from any cause for the diabetic group of 0.64 (95% confidence interval 0.45 to 0.91) versus 0.82 (0.69 to 0.97) for the nondiabetic group. In the diabetic group, trandolapril reduced the risk of progression to severe heart failure markedly (RR, 0.38 [0.21 to 0.67]), and no significant reduction of this end point was found in the nondiabetic group.

CONCLUSIONS

The ACE inhibition after myocardial infarction complicated by left ventricular dysfunction appears to be of considerable importance in patients with diabetes mellitus by saving lives and substantially reducing the risk of progression to severe heart failure.

Left ventricular size and function in patients with noninsulin-dependent diabetes and postinfarction total or subtotal coronary occlusions

The aim of this study was to establish the effects of postinfarction total or subtotal coronary occlusion on left ventricular remodeling in patients with noninsulin-dependent diabetes (NIDD) compared with the effects in postinfarct nondiabetic patients. The authors selected 100 patients submitted to coronary angiography between 1 and 5 weeks after acute myocardial infarction (T0: 20.5+/-15.4 days) and classified into three groups: G1: NIDD with coronary occlusion/subocclusion (n=24), G2: controls with coronary occlusion/subocclusion (n=43), G3: controls without coronary occlusion/subocclusion (n=33). At time zero (T0) the following parameters were evaluated: end-systolic and end-diastolic volume indexes (ESVi, EDVi), ejection fraction (EF), echocardiographic wall motion score index (WMI), presence of left ventricular aneurysm, and triple-vessel coronary disease. The frequencies of major cardiovascular events were recorded during follow-up. Significantly greater ESVi and EDVi were noted in G2 compared with G3 (P<0.0001), while no significant differences were observed between NIDD patients and controls. Although left ventricular global and segmental dysfunctions were increased in diabetics, controls with coronary occlusion/subocclusion presented more pronounced EF reduction (P<0.0001 G2 vs G3) and higher elevation in WMI (P<0.005 G2 vs G3). Cardiac events during follow-up were elevated in G1 and G2, particularly as regards the occurrence of congestive heart failure. The authors conclude that NIDD seems to influence in a positive way left ventricular remodeling associated with postinfarct total or subtotal coronary occlusion.

Randomized trial of insulin-glucose infusion followed by subcutaneous insulin treatment in diabetic patients with acute myocardial infarction (DIGAMI study): effects on mortality at 1 year

OBJECTIVES

We tested how insulin-glucose infusion followed by multidose insulin treatment in diabetic patients with acute myocardial infarction affected mortality during the subsequent 12 months of follow-up.

BACKGROUND

Despite significant improvements in acute coronary care, diabetic patients with acute myocardial infarction still have a high mortality rate.

METHODS

A total of 620 patients were studied: 306 randomized to treatment with insulin-glucose infusion followed by multidose subcutaneous insulin for > or = 3 months and 314 to conventional therapy.

RESULTS

The two groups were well matched for baseline characteristics. Blood glucose decreased from 15.4 +/- 4.1 to 9.6 +/- 3.3 mmol/liter (mean +/- SD) in the infusion group during the 1st 24 h, and from 15.7 +/- 4.2 to 11.7 +/- 4.1 among control patients (p < 0.0001). After 1 year 57 subjects (18.6%) in the infusion group and 82 (26.1%) in the control group had died (relative mortality reduction 29%, p = 0.027). The mortality reduction was particularly evident in patients who had a low cardiovascular risk profile and no previous insulin treatment (3-month mortality rate 6.5% in the infusion group vs. 13.5% in the control group [relative reduction 52%, p = 0.046]; 1-year mortality rate 8.6% in the infusion group vs. 18.0% in the control group [relative reduction 52%, p = 0.020]).

CONCLUSIONS

Insulin-glucose infusion followed by a multidose insulin regimen improved long-term prognosis in diabetic patients with acute myocardial infarction.