Clinical and angiographic risk stratification and differential impact on treatment outcomes in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial

BACKGROUND

The Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial assigned patients with type 2 diabetes mellitus to prompt coronary revascularization plus intensive medical therapy versus intensive medical therapy alone and reported no significant difference in mortality. Among patients selected for coronary artery bypass graft surgery, prompt coronary revascularization was associated with a significant reduction in death/myocardial infarction/stroke compared with intensive medical therapy. We hypothesized that clinical and angiographic risk stratification would affect the effectiveness of the treatments overall and within revascularization strata.

METHODS AND RESULTS

An angiographic risk score was developed from variables assessed at randomization; independent prognostic factors were myocardial jeopardy index, total number of coronary lesions, prior coronary revascularization, and left ventricular ejection fraction. The Framingham Risk Score for patients with coronary disease was used to summarize clinical risk. Cardiovascular event rates were compared by assigned treatment within high-risk and low-risk subgroups. Overall, no outcome differences between the intensive medical therapy and prompt coronary revascularization groups were seen in any risk stratum. The 5-year risk of death/myocardial infarction/stroke was 36.8% for intensive medical therapy compared with 24.8% for prompt coronary revascularization among the 381 coronary artery bypass graft surgery-selected patients in the highest angiographic risk tertile (P=0.005); this treatment effect was amplified in patients with both high angiographic and high Framingham risk (47.3% intensive medical therapy versus 27.1% prompt coronary revascularization; P=0.010; hazard ratio=2.10; P=0.009). Treatment group differences were not significant in other clinical-angiographic risk groups within the coronary artery bypass graft surgery stratum, or in any subgroups within the percutaneous coronary intervention stratum.

CONCLUSION

Among patients with diabetes mellitus and stable ischemic heart disease, a strategy of prompt coronary artery bypass graft surgery significantly reduces the rate of death/myocardial infarction MI/stroke in those with extensive coronary artery disease or impaired left ventricular function.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00006305.

Direct comparison of Takotsubo cardiomyopathy between Japan and USA: 3-year follow-up study

OBJECTIVE

Takotsubo cardiomyopathy (TC) mimics myocardial infarction and is well defined and known to not only Japan but also western countries. However, whether or not there are differences in the characteristics of TC between Japan and USA remains unknown.

PATIENTS

Data for patients who had undergone urgent left heart catheterization for suspected acute coronary syndrome were retrospectively retrieved from Keio University School of Medicine (KUSM) database in Japan and Lahey Clinic Medical Center (LCMC) database in USA between 2002 and 2007.

RESULTS

During the study period, 626 coronary angiographies were performed in KUSM and 1,880 coronary angiographies were performed in LCMC. Twelve patients in Japan and 34 patients in USA met the inclusion criteria. Mean age of patients in Japan was 75 years where 92% were women, compared to 67 years and 94% women in USA. Although the prevalence of hypertension, dyslipidemia and diabetes mellitus were similar between Japan and USA, there was a trend towards fewer patients in Japan displaying a history of coronary revascularization. Surprisingly, a family history of premature coronary artery disease (CAD) was present in 21% of USA patients, whereas no patients were present in Japan. There were no differences in the incidence of readmission for heart failure, cardiac death and TC recurrence during the follow-up period.

CONCLUSION

Patients with TC in Japan have fewer prior overt CAD and fewer family history of premature CAD, but no significant differences were found in the long-term prognosis and the recurrence rate between patients in Japan and USA.

Presentation in patients with angiographically documented coronary artery disease and type II diabetes mellitus (from the BARI 2D Clinical Trial)

Clinically stable patients with type 2 diabetes mellitus and coronary artery disease are not often thought to present with the symptom of typical angina. The aims of this study were to enumerate the proportion of patients presenting with typical angina or other cardiac symptoms and to elucidate what important clinical variables are associated with the presence of typical angina in patients with type 2 diabetes mellitus and angiographically documented coronary artery disease. Symptoms of angina, anginal equivalents, or an absence of symptoms were obtained using baseline data from the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial (n = 2,319). A bivariate analysis stratified by the presence or absence of previous revascularization and logistic regression modeling with a stepwise covariate selection was used. Eighty-two percent of patients had symptoms, while 18% presented asymptomatically. This was further divided approximately into typical angina (1/5), anginal equivalents (1/5), combination (2/5), and asymptomatic (1/5). A history of previous revascularization was a determinant of the type of symptom presentation with regard to the variables gender, age, current insulin use, myocardial jeopardy index score, and use of β blockers. In the multivariate logistic regression analysis, of the available candidate variables, only a history of β-blocker use (odds ratio 1.53, 95% confidence interval 1.24 to 1.94, p <0.0001) and previous percutaneous coronary intervention (odds ratio 1.55, 95% confidence interval 1.24 to 1.94, p <0.0001) had higher odds of an association with typical angina. In conclusion, a large proportion of patients with type 2 diabetes mellitus and coronary artery disease indeed have symptoms. Future studies of long-term outcomes associated with these symptoms are needed.

Blood pressure, lipids and glucose in type 2 diabetes: how low should we go? Re-discovering personalized care

Epidemiological studies have clearly shown a direct relationship between the levels of blood pressure, glycaemia and LDL-cholesterol, and the complications of diabetes. Although 'lower should be better', the results of recent clinical trials examining the benefits of normalizing risk factor levels have been counter-intuitive and, at times, disturbing, and have called into question this notion. This review focuses on patients with type 2 diabetes who make up 90% of patients with diabetes. It aims to provide a clear summary and interpretation of recent trials to help clinicians to set targets for cardiovascular risk factors in individual patients. It highlights areas of agreement and disagreement between current guidelines. Recent data indicate that some patient subgroups might respond differently to aggressive risk factor management. Our challenge is how to identify these patients and deliver truly personalized diabetes care that maximizes benefit, and minimizes harm. Guidelines and position statements stress the value of setting personalized targets. We explore what this means, and how this might be achieved in practice by outlining some solutions to issues that currently limit the delivery of personalized care. We call for further research assessing the overall clinical impact of cardiovascular risk factor intervention by finding appropriate ways of combining data on mortality, complications, side-effects, quality of life, and cost-effectiveness.

Resting heart rate and metabolic syndrome in patients with diabetes and coronary artery disease in bypass angioplasty revascularization investigation 2 diabetes (BARI 2D) trial

The relation between the metabolic syndrome (MetS) and resting heart rate (rHR) in patients with diabetes and coronary artery disease is unknown. The authors examined the cross-sectional association at baseline between components of the MetS and rHR and between rHR and left ventricular ejection fraction in the population from the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) randomized clinical trial. The mean rHR in the MetS group was significantly higher than in those without (68.4+/-12.3 vs 65.6+/-11.8 beats per min, P=.0017). The rHR was higher (P<.001 for trend) with increasing number of components for MetS. Linear regression analyses demonstrated that as compared to individuals without MetS, rHR was significantly higher in participants with MetS (regression coefficient, 2.9; P=.0015). In patients with type 2 diabetes and coronary artery disease, the presence of higher rHR is associated with increasing number of criteria of MetS and the presence of ventricular dysfunction.

Cardiac Resynchronization Therapy Reduces the Risk of Cardiac Events in Patients With Diabetes Enrolled in the Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy (MADIT-CRT)

Background—

Data are limited regarding whether the presence of diabetes mellitus (DM) influences the benefit of cardiac resynchronization with defibrillator therapy (CRT-D) in heart failure (HF) patients.

Methods and Results—

The effect of CRT-D was evaluated in 1817 patients who were enrolled in the Multicenter Automatic Defibrillator Implantation Trial with Cardiac Resynchronization Therapy (MADIT-CRT). Patients were minimally symptomatic (New York Heart Association class I or II), with ejection fraction ≤0.30 and QRS ≥130 ms. We used Cox regression to determine hazard ratio (HR) of CRT-D versus implantable cardioverter-defibrillator (ICD) therapy for the risk of HF event or death, whichever came first (MADIT-CRT primary end point), in DM (n=552) and non-DM (n=1265) patients. Compared with the non-DM patients, those with DM had more coronary risk factors. During an average follow-up of 2.4 years, DM patients had significantly more primary end point events than non-DM patients (26.6% versus 18%, P <0.001). CRT-D was associated with a significant reduction in risk of primary end point in both DM (HR=0.56, P <0.001) and non-DM patients (HR=0.67, P =0.003). Compared with non-DM patients, CRT-D:ICD HRs in DM patients were lower in the total population, and in subgroups with ischemic cardiomyopathy (0.63 versus 0.64), nonischemic cardiomyopathy (0.39 versus 0.73), and left bundle-branch block (0.36 versus 0.50). There were no significant differences in ventricular remodeling, arrhythmia events, or device-related complications between DM and non-DM patients.

Conclusions—

Patients with diabetes, left ventricular dysfunction, mildly symptomatic HF, and wide QRS complex derive similar benefit from CRT-D compared with patients without diabetes.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00180271.

The prevalence and predictors of an abnormal ankle-brachial index in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial

OBJECTIVE

To examine ankle-brachial index (ABI) abnormalities in patients with type 2 diabetes and coronary artery disease (CAD).

RESEARCH DESIGN AND METHODS

An ABI was obtained in 2,240 patients in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) Trial. ABIs were classified as: normal, 0.91-1.3; low, ≤ 0.9; high, >1.3; or noncompressible artery (NC). Baseline characteristics were examined according to ABI and by multivariate analysis. RESULTS ABI was normal in 66%, low in 19%, and high in 8% of patients, and 6% of patients had NC. Of the low ABI patients, 68% were asymptomatic. Using normal ABI as referent, low ABI was independently associated with smoking, female sex, black race, hypertension, age, C-reactive protein, diabetes duration, and lower BMI. High ABI was associated with male sex, nonblack race, and higher BMI; and NC artery was associated with diabetes duration, higher BMI, and hypertension.

CONCLUSIONS

ABI abnormalities are common and often asymptomatic in patients with type 2 diabetes and CAD.

Evolution of percutaneous coronary intervention in patients with diabetes: a report from the National Heart, Lung, and Blood Institute-sponsored PTCA (1985-1986) and Dynamic (1997-2006) Registries

OBJECTIVE

To evaluate the association of successive percutaneous coronary intervention (PCI) modalities with balloon angioplasty (BA), bare-metal stent (BMS), drug-eluting stents (DES), and pharmacotherapy over the last 3 decades with outcomes among patients with diabetes in routine clinical practice.

RESEARCH DESIGN AND METHODS

We examined outcomes in 1,846 patients with diabetes undergoing de novo PCI in the multicenter, National Heart, Lung, and Blood Institute-sponsored 1985-1986 Percutaneous Transluminal Coronary Angioplasty (PTCA) Registry and 1997-2006 Dynamic Registry. Multivariable Cox regression models were used to estimate the adjusted risk of events (death/myocardial infarction [MI], repeat revascularization) over 1 year.

RESULTS

Cumulative event rates for postdischarge (31-365 days) death/MI were 8% by BA, 7% by BMS, and 7% by DES use (P = 0.76) and for repeat revascularization were 19, 13, and 9% (P < 0.001), respectively. Multivariable analysis showed a significantly lower risk of repeat revascularization with DES use when compared with the use of BA (hazard ratio [HR] 0.41 [95% CI 0.29-0.58]) and BMS (HR 0.55 [95% CI 0.39-0.76]). After further adjustment for discharge medications, the lower risk for death/MI was not statistically significant for DES when compared with BA.

CONCLUSIONS

In patients with diabetes undergoing PCI, the use of DES is associated with a reduced need for repeat revascularization when compared with BA or BMS use. The associated death/MI benefit observed with the DES versus the BA group may well be due to greater use of pharmacotherapy.

Influence of diabetes and/or myocardial infarction on prevalence of abnormal T-wave alternans

BACKGROUND

Subjects with microvolt-level T-wave alternans (TWA) in association with structural heart disease have an increased risk for sudden cardiac death. The presence of diabetes (DM) is associated with an increased risk of sudden death but there is limited data on the impact of DM and previous myocardial infarction (MI) on TWA prevalence.

METHODS

We performed a case-control cross-sectional study in 140 patients referred for routine exercise testing within a large multispecialty clinic. All patients with a history of DM and MI status within the past year were eligible: group 1 (no DM or MI), group 2 (DM only), group 3 (MI only), group 4 (DM and MI). Patients performed a symptom-limited Bruce protocol exercise test with assessment of TWA by the spectral method using commercially available equipment. We used published criteria for the blinded interpretation of TWA; all tests not unequivocally negative were considered abnormal.

RESULTS

Age and gender were similar in all groups. The prevalence of abnormal TWA in groups 1-4 was 24%, 20%, 48%, and 62%, respectively (between group P = 0.002). Logistic regression analysis in all patients showed that abnormal TWA was related to prior MI [OR (95% CI): 4.0 (1.8-8.9), P < 0.001] but not to prevalent DM [0.9 (0.4-1.8), P = 0.72]. In patients with DM, the prevalence of abnormal TWA was related to reduced ejection fraction (P = 0.034) but not to BMI, DM duration, glycemic control, insulin use, or the presence of microvascular complications.

CONCLUSION

The presence of DM alone does not increase risk of abnormal TWA. Prospective studies are required to establish the prognostic value of TWA in patients with DM.

The BARI 2D study: a randomised trial of therapies for type 2 diabetes and coronary artery disease

The Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial randomized 2368 patients with type 2 diabetes (T2DM) and coronary artery disease to either prompt revascularization or intensive medical therapy alone; and to either insulin-sensitization or insulin-provision diabetes therapy. Randomization was stratified by proposed revascularization method. Five-year survival and major cardiovascular events (MACE) were similar in study subgroups except in the coronary bypass surgery (CABG) stratum where there were fewer MACE after revascularization. There was less hypoglycaemia and weight gain, and greater apparent benefit from CABG in the insulin sensitization group. BARI 2D has provided important data for clinicians.

Comparison of incidence of acute myocardial infarction in patients with type 2 diabetes mellitus following initiation of neutral protamine Hagedorn insulin versus insulin glargine

Recent reports have described different risks of acute myocardial infarction (AMI) in association with specific oral antidiabetic medications. The present study compared the AMI incidence rates in new users of traditional neutral protamine Hagedorn (NPH) insulin and a long-acting synthetic insulin analog for basal insulin therapy. We retrospectively examined in-patient medical claims for AMI in a cohort of oral agent-treated patients with type 2 diabetes mellitus after the initiation of basal insulin therapy with either NPH (n = 5,461) or insulin glargine (n = 14,730) in a national administrative claims database comprising >30 managed healthcare plans in the United States. Poisson regression and Cox proportional hazards regression models, as well as the propensity score methods, were used to compare the subsequent AMI incidence rates after the initiation of NPH or glargine. At a mean follow-up of 2 years, the unadjusted AMI incidence was 17.6/1,000 person-years after the initiation of NPH versus 11.5/1,000 person-years after initiation of glargine (rate ratio 1.53, 95% confidence interval 1.29 to 1.81). The Cox regression model (hazard ratio 1.39, 95% confidence interval 1.14 to 1.69) and sensitivity analyses (hazard ratio range 1.30 to 1.56) showed a greater risk of AMI in the NPH group than in the glargine group. Propensity matched (1:1) analysis yielded similar results (odds ratio 1.55, 95% confidence interval 1.23 to 1.96 for NPH vs glargine). In conclusion, these results suggest that the initiation of basal insulin therapy with NPH rather than glargine in patients with type 2 diabetes mellitus is associated with a greater risk of AMI.

In vivo validation of a catheter-based near-infrared spectroscopy system for detection of lipid core coronary plaques: initial results of the SPECTACL study

OBJECTIVES

To determine whether catheter-based near-infrared spectroscopy (NIRS) signals obtained with a novel catheter-based system from coronaries of patients are similar to those from autopsy specimens and to assess initial safety of NIRS device.

BACKGROUND

An intravascular NIRS system for detection of lipid core-containing plaques (LCP) has been validated in human coronary autopsy specimens. The SPECTACL (SPECTroscopic Assessment of Coronary Lipid) trial was a parallel first-in-human multicenter study designed to demonstrate the applicability of the LCP detection algorithm in living patients.

METHODS

Intracoronary NIRS was performed in patients undergoing percutaneous coronary intervention. Acquired spectra were blindly compared with autopsy NIRS signals with multivariate statistics. To meet the end point of spectral similarity, at least two-thirds of the scans were required to have >80% of spectra similar to the autopsy spectra.

RESULTS

A total of 106 patients were enrolled; there were no serious adverse events attributed to NIRS. Spectroscopic data could not be obtained in 17 (16%) patients due to technical limitations, leaving 89 patients for analysis. Spectra from 30 patients were unblinded to test the calibration of the LCP detection algorithm. Of the remaining 59 blinded cases, after excluding 11 due to inadequate data, spectral similarity was demonstrated in 40 of 48 spectrally adequate scans (83% success rate, 95% confidence interval: 70% to 93%, median spectral similarity/pullback: 96%, interquartile range 10%). The LCP was detected in 58% of 60 spectrally similar scans from both cohorts.

CONCLUSIONS

This intravascular NIRS system safely obtained spectral data in patients that were similar to those from autopsy specimens. These results demonstrate the feasibility of invasive detection of coronary LCP with this novel system. (SPECTACL: SPECTroscopic Assessment of Coronary Lipid; NCT00330928).

A randomized trial of therapies for type 2 diabetes and coronary artery disease

BACKGROUND

Optimal treatment for patients with both type 2 diabetes mellitus and stable ischemic heart disease has not been established.

METHODS

We randomly assigned 2368 patients with both type 2 diabetes and heart disease to undergo either prompt revascularization with intensive medical therapy or intensive medical therapy alone and to undergo either insulin-sensitization or insulin-provision therapy. Primary end points were the rate of death and a composite of death, myocardial infarction, or stroke (major cardiovascular events). Randomization was stratified according to the choice of percutaneous coronary intervention (PCI) or coronary-artery bypass grafting (CABG) as the more appropriate intervention.

RESULTS

At 5 years, rates of survival did not differ significantly between the revascularization group (88.3%) and the medical-therapy group (87.8%, P=0.97) or between the insulin-sensitization group (88.2%) and the insulin-provision group (87.9%, P=0.89). The rates of freedom from major cardiovascular events also did not differ significantly among the groups: 77.2% in the revascularization group and 75.9% in the medical-treatment group (P=0.70) and 77.7% in the insulin-sensitization group and 75.4% in the insulin-provision group (P=0.13). In the PCI stratum, there was no significant difference in primary end points between the revascularization group and the medical-therapy group. In the CABG stratum, the rate of major cardiovascular events was significantly lower in the revascularization group (22.4%) than in the medical-therapy group (30.5%, P=0.01; P=0.002 for interaction between stratum and study group). Adverse events and serious adverse events were generally similar among the groups, although severe hypoglycemia was more frequent in the insulin-provision group (9.2%) than in the insulin-sensitization group (5.9%, P=0.003).

CONCLUSIONS

Overall, there was no significant difference in the rates of death and major cardiovascular events between patients undergoing prompt revascularization and those undergoing medical therapy or between strategies of insulin sensitization and insulin provision. (ClinicalTrials.gov number, NCT00006305.)

Differential effects of extended-release carvedilol and extended-release metoprolol on lipid profiles in patients with hypertension: results of the Extended-Release Carvedilol Lipid Trial

Some beta-blockers, although they are effective antihypertensive agents, may adversely effect dyslipidemia and decrease insulin sensitivity. beta-blockers without adverse metabolic effects may provide an improvement in long-term hypertension therapy. Hypertensive patients (n = 568) without diabetes, not requiring lipid-lowering therapy, were randomized to once-daily extended-release carvedilol or extended-release metoprolol and titrated to target blood pressure (BP). Co-primary endpoints were comparison between groups in high-density lipoprotein (HDL) or triglycerides at 24 weeks. Extended-release carvedilol was superior to extended-release metoprolol in meeting the primary endpoint of a difference in triglycerides; the median % change in triglycerides being -8.026% (P = .0141; 97.5% confidence interval [CI], -15.35, -0.67)] from baseline to 24 weeks. Triglycerides were unchanged with carvedilol and increased with metoprolol. There was no significant difference in effect on HDL. BP was similar between treatment groups. There was a significant decrease with extended-release carvedilol vs. extended-release metoprolol in insulin (-2.56 muU/mL [P = .0213; 95% CI, -4.74 to -0.38]) and c-peptide [(-0.43 ng/mL [P = .0007; 95% CI, -0.68 to -0.18]). In hypertension, extended-release carvedilol resulted in lower triglycerides, insulin, and C-peptide levels compared with extended-release metoprolol. Similar effects were observed in high-risk subgroups. Both treatments were well tolerated. This differential metabolic profile could be useful in determining antihypertensive treatment options.

Type 2 diabetes and coronary heart disease: focus on myocardial infarction

Individuals with type 2 diabetes are more likely to experience a myocardial infarction and have worse outcomes compared with nondiabetic individuals. The underlying pathophysiology of the atherosclerotic process is accentuated but not significantly different in patients with type 2 diabetes. In addition, the prothrombotic state associated with diabetes may also contribute to the higher incidence of and worse prognosis after myocardial infarction. Difficulties of re-establishing vessel patency by thrombolytic or mechanical means due to diffuse coronary disease, altered vessel structure, and prothrombotic state can contribute to the high morbidity and mortality in these patients. The concurrent metabolic dysfunction contributes to impair compensatory mechanisms, which can increase infarct size and cause more impairment of left ventricular function. Aggressive medical therapy and careful modulation of glucose metabolism in the acute and follow-up phase of a myocardial infarction may favorably influence outcome.

Assessment on the Prevention of Progression by Rosiglitazone on Atherosclerosis in diabetes patients with Cardiovascular History (APPROACH): study design and baseline characteristics

BACKGROUND

Rosiglitazone, a thiazolidinedione, has effects on insulin sensitivity and cardiovascular risk factors that may favorably impact the progression of coronary atherosclerosis.

METHODS

APPROACH is a double-blind randomized clinical trial comparing the effects of the insulin sensitizer rosiglitazone with the insulin secretagogue glipizide on the progression of coronary atherosclerosis. Patients with type 2 diabetes and coronary artery disease undergoing clinically indicated coronary angiography or percutaneous coronary intervention are randomized to receive rosiglitazone or glipizide for 18 months using a titration algorithm designed to provide comparable glycemic control between treatment groups. The primary end point is change in percent atheroma volume from baseline to study completion in a nonintervened coronary artery, as measured by intravascular ultrasound. Cardiovascular events are adjudicated by an end point committee.

RESULTS

A total of 672 patients were randomized. The mean age was 61 years, hemoglobin A(1c) (HbA(1c)) 7.2%, body mass index 29.5 kg/m(2), and median duration of diabetes 4.8 years. At baseline, approximately half of the participants were receiving oral antidiabetic monotherapy (53.9%) with 27.5% receiving dual combination therapy and 17.9% treated with diet and exercise alone. Approximately two thirds of the participants (68%) had dyslipidemia, 79.9% hypertension, and 24% prior myocardial infarction.

CONCLUSIONS

APPROACH has fully enrolled a high-risk patient population and will compare the glucose-independent effects of rosiglitazone and glipizide on the progression of coronary atherosclerosis, as well as provide additional data on the cardiovascular safety of rosiglitazone in patients with type 2 diabetes and coronary artery disease.

Myocardial glucose transport and utilization: a target for therapeutic intervention

Patients with type 2 diabetes mellitus (T2DM) have a 2-fold to 4-fold greater risk of cardiovascular mortality than nondiabetic individuals. The overall mortality rate of patients with T2DM is approximately twice that of people without diabetes. The excess in-hospital mortality of these patients is primarily due to an increased risk of congestive heart failure. Reduced compensatory ability of the noninfarcted myocardium and an underlying abnormality in the myocardial substrate metabolism (referable to the diabetic state) may also contribute to poor outcomes. Insulin resistance (IR) is a significant predictor of cardiovascular mortality and morbidity across a spectrum of glucose tolerance. Cardiac mass increases across the range of IR in subjects without diabetes, as well as across the range of glucose intolerance in subjects with diabetes. In one study, elevated fasting plasma glucose was an independent predictor of hospitalization for heart failure. Optimization of cardiac metabolism could become a new target for therapeutic intervention in patients with ischemic heart disease and diabetes.

Grand rounds: asbestos-related pericarditis in a boiler operator

CONTEXT

Occupational and environmental exposures to asbestos remain a public health problem even in developed countries. Because of the long latency in asbestos-related pathology, past asbestos exposure continues to contribute to incident disease. Asbestos most commonly produces pulmonary pathology, with asbestos-related pleural disease as the most common manifestation. Although the pleurae and pericardium share certain histologic characteristics, asbestos-related pericarditis is rarely reported.

CASE PRESENTATION

We present a 59-year-old man who worked around boilers for almost 30 years and was eventually determined to have calcific, constrictive pericarditis. He initially presented with an infectious exacerbation of chronic bronchitis. Chest radiographs demonstrated pleural and pericardial calcifications. Further evaluation with cardiac catheterization showed a hemodynamic picture consistent with constrictive pericarditis. A high-resolution computerized tomography scan of the chest demonstrated dense calcification in the pericardium, right pleural thickening and nodularity, right pleural plaque without calcification, and density in the right middle lobe. Pulmonary function testing showed mild obstruction and borderline low diffusing capacity.

DISCUSSION

Based on the patient's occupational history, the presence of pleural pathology consistent with asbestos, previous evidence that asbestos can affect the pericardium, and absence of other likely explanations, we concluded that his pericarditis was asbestos-related.

RELEVANCE TO CLINICAL PRACTICE

Similar to pleural thickening and plaque formation, asbestos may cause progressive fibrosis of the pericardium.

Prevalence of metabolic syndrome in patients < or =45 years of age with acute myocardial infarction having percutaneous coronary intervention

The prevalence of metabolic syndrome (MS) was determined in patients aged < or =45 years who presented with acute myocardial infarction and underwent primary percutaneous coronary intervention. Two hundred twenty-three consecutive patients aged 18 to 45 years who underwent cardiac catheterization for acute myocardial infarction from June 2001 to December 2004 were reviewed. MS was diagnosed by National Cholesterol Education Program Adult Treatment Panel III guidelines (modified by substituting body mass index > or =28.8 kg/m2 for waist circumference). One hundred sixty-one patients met all 5 criteria for MS available for evaluation. Seventy-six of these patients (47%) met > or =3 of the 5 criteria for MS. Sixteen patients with MS (21%) and 5 patients without MS (6%) had diabetes mellitus. The prevalence of each criterion was significantly higher (p <0.05) in the MS group. Average Framingham risk scores were 7.0 and 4.5 for patients with and without MS, respectively. The prevalence of smoking, male gender, and family history of premature coronary artery disease were the same for the 2 groups. In conclusion, MS was highly prevalent in this population of young patients with acute myocardial infarction.

Congestive heart failure and cardiovascular death in patients with prediabetes and type 2 diabetes given thiazolidinediones: a meta-analysis of randomised clinical trials

BACKGROUND

The overall clinical benefit of thiazolidinediones (TZDs) as a treatment for hyperglycaemia can be difficult to assess because of the risk of congestive heart failure due to TZD-related fluid retention. Since prediabetic and diabetic patients are at high cardiovascular risk, the outcome and natural history of such risks need to be better understood. We aimed to examine the risk of congestive heart failure and of cardiac death in patients given TZDs.

METHODS

We used a search strategy to identify 3048 studies. 3041 were excluded, and we did a systematic review and meta-analysis of the seven remaining randomised double-blind clinical trials of drug-related congestive heart failure in patients given TZDs (either rosiglitazone or pioglitazone). We calculated pooled random-effects estimates of the risk ratios for development of congestive heart failure in patients given TZDs compared with controls. The main outcome measures were development of congestive heart failure and the risk of cardiovascular death.

FINDINGS

360 of 20 191 patients who had either prediabetes or type 2 diabetes had congestive heart failure events (214 with TZDs and 146 with comparators). Results showed no heterogeneity of effects across studies (I2=22.8%; p for interaction=0.26), which indicated a class effect for TZDs. Compared with controls, patients given TZDs had increased risk for development of congestive heart failure across a wide background of cardiac risk (relative risk [RR] 1.72, 95% CI 1.21-2.42, p=0.002). By contrast, the risk of cardiovascular death was not increased with either of the two TZDs (0.93, 0.67-1.29, p=0.68).

INTERPRETATION

Congestive heart failure in patients given TZDs might not carry the risk that is usually associated with congestive heart failure which is caused by progressive systolic or diastolic dysfunction of the left ventricle. Longer follow-up and better characterisation of such patients is needed to determine the effect of TZDs on overall cardiovascular outcome.

The changing costs and benefits of screening for asymptomatic coronary heart disease in patients with diabetes

Aggressive medical therapy can be justified in most patients with diabetes, but there may be some higher-risk asymptomatic patients who could benefit from revascularization and/or medical therapy for myocardial ischemia. Silent myocardial ischemia (SMI) might be used to identify these high-risk individuals. In this Review we define SMI as objective evidence of ischemia from any noninvasive test occurring in an asymptomatic patient. We outline what is known about asymptomatic coronary heart disease (CHD) in diabetes and how this relates to SMI. We examine how SMI predicts angiographic CHD and CHD events, and we describe the changing role of CHD screening as reflected by various guidelines. We identify the recent research suggesting that there may be substantial numbers of high-risk asymptomatic patients who have diabetes with undiagnosed CHD and who could benefit from more-active intervention; however, with the recent advances in medical therapy, and the uncertain benefits of screening, current guidelines strongly discourage this practice, except in limited clinical situations, such as before major surgery. Carefully conducted clinical trails using state-of-the-art investigations and therapy in well-characterized patients with diabetes are urgently required to inform physicians on when and how to intervene.

Primary prevention of cardiovascular diseases in people with diabetes mellitus: a scientific statement from the American Heart Association and the American Diabetes Association

The American Heart Association (AHA) and the American Diabetes Association (ADA) have each published guidelines for cardiovascular disease prevention: the ADA has issued separate recommendations for each of the cardiovascular risk factors in patients with diabetes, and the AHA has shaped primary and secondary guidelines that extend to patients with diabetes. This statement will attempt to harmonize the recommendations of both organizations where possible but will recognize areas in which AHA and ADA recommendations differ.

Stroke Complicating Percutaneous Coronary Intervention in Patients With Acute Myocardial Infarction

BACKGROUND

Stroke associated with percutaneous coronary intervention (PCI) is a tragic complication. Despite advances in the practice of PCI, the incidence of stroke complicating PCI has not changed over the decades. The objective of the present study was to evaluate incidence and correlates of stroke occurring in patients with myocardial infarction (MI) undergoing PCI.

METHODS AND RESULTS

Stroke was defined as the presence of any new focal neurological deficit lasting > or =24 h that occurred anytime during or after PCI until discharge. In 2,281 consecutive patients with PCIs for non-ST-elevation MI, or ST-elevation MI (STEMI), 20 strokes were identified (0.88%). Strokes were ischemic in 95%. On multivariate analyses, ejection fraction < or =30% (odds ratio =4.3, p=0.003) was the only independent predictor for stroke. In patients who developed stroke within 24 h of PCI, PCI of vein grafts was more frequent, and use of glycoprotein IIb/IIIa inhibitor was less frequent. Those patients tended to present late in the course of MI. Stroke found more than 24 h after PCI was related to diabetes, higher serum creatinine, lower ejection fraction, anterior wall STEMI and emergency use of intra-aortic balloon pumps.

CONCLUSIONS

Low ejection fraction was the only independent predictor for stroke, but risk factors for periprocedural stroke are different from those of stroke occurring more than 24 h after PCI. Upstream use of glycoprotein IIb/IIIa inhibitor might decrease the risk of periprocedural stroke.

Primary prevention of cardiovascular diseases in people with diabetes mellitus: a scientific statement from the American Heart Association and the American Diabetes Association

The American Heart Association (AHA) and the American Diabetes Association (ADA) have each published guidelines for cardiovascular disease prevention: The ADA has issued separate recommendations for each of the cardiovascular risk factors in patients with diabetes, and the AHA has shaped primary and secondary guidelines that extend to patients with diabetes. This statement will attempt to harmonize the recommendations of both organizations where possible but will recognize areas in which AHA and ADA recommendations differ.

Modifications of coronary risk factors

In addition to the revascularization and glycemic management interventions assigned at random, the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) design includes the uniform control of major coronary artery disease risk factors, including dyslipidemia, hypertension, smoking, central obesity, and sedentary lifestyle. Target levels for risk factors were adjusted throughout the trial to comply with changes in recommended clinical practice guidelines. At present, the goals are low-density lipoprotein cholesterol <2.59 mmol/L (<100 mg/dL) with an optional goal of <1.81 mmol/L (<70 mg/dL); plasma triglyceride level <1.70 mmol/L (<150 mg/dL); blood pressure level <130 mm Hg systolic and <80 mm Hg diastolic; and smoking cessation treatment for all active smokers. Algorithms were developed for the pharmacologic management of dyslipidemia and hypertension. Dietary prescriptions for the management of glycemia, plasma lipid profiles, and blood pressure levels were adapted from existing clinical practice guidelines. Patients with a body mass index >25 were prescribed moderate caloric restriction; after the trial was under way, a lifestyle weight-management program was instituted. All patients were formally prescribed both endurance and resistance/flexibility exercises, individually adapted to their level of disability and fitness. Pedometers were distributed as a biofeedback strategy. Strategies to achieve the goals for risk factors were designed by BARI 2D working groups (lipid, cardiovascular and hypertension, and nonpharmacologic intervention) and the ongoing implementation of the strategies is monitored by lipid, hypertension, and lifestyle intervention management centers.

Antiplatelet therapy in populations at high risk of atherothrombosis

Atherothrombosis is the most common cause of an acute ischemic event. Antiplatelet agents form the cornerstone of atherothrombosis prevention. The purpose of this article is to review the use of antiplatelet agents in patients that are at particularly high risk of atherothrombotic events. To undertake this review, we searched the literature to identify key studies on the use of antiplatelet agents in this group of patients. Antiplatelet agents, such as aspirin and clopidogrel, play a fundamental role in the treatment and management of secondary thrombotic events. The routine use of aspirin is recommended, as it has been shown to reduce the risk of thrombotic events by approximately 25%. Additional benefit has been demonstrated with clopidogrel, both as a monotherapy and in combination with aspirin. In the CAPRIE trial, 19,185 patients with atherosclerotic vascular disease were randomized to receive clopidogrel (75 mg/day) or aspirin (325 mg/day) for a mean duration of follow-up of 1.91 years. Clopidogrel provided an additional 8.7% relative risk reduction in the primary composite endpoint of ischemic stroke, myocardial infraction or vascular death compared with aspirin. In the CURE trial, the addition of clopidogrel to background aspirin was associated with a 20% relative risk reduction in a composite of death from cardiovascular causes, nonfatal myocardial infarction or stroke compared with aspirin alone. In patients undergoing PCI as part of the PCI-CURE substudy, clopidogrel was associated with a 30% relative reduction in the incidence of cardiovascular events in the first 30 days after intervention compared with aspirin. The benefits of antiplatelet therapy continue to be investigated. Whether dual antiplatelet therapy is superior to aspirin monotherapy for high-risk primary prevention is unknown. The ongoing CHARISMA trial aims to determine the relative efficacies of aspirin monotherapy and aspirin/clopidogrel combination therapy in a broad range of high-risk patient populations. In addition, the REACH registry, a worldwide survey of symptomatic and high-risk patients, has been set up to provide vital epidemiological information regarding the risks of atherothrombosis in order to contribute to the development of better preventive strategies and management regimens for at-risk patients.

Near-infrared spectroscopy for the detection of vulnerable coronary artery plaques

This review describes efforts to use near-infrared (NIR) spectroscopy to identify chemical components of coronary artery plaques as a means to assess vulnerability. Near-infrared spectroscopy has been well-validated by the physical sciences as a method to characterize chemical composition of various bio-materials and could be ideal to detect vulnerable coronary plaques in patients. Recent studies in aortic and coronary artery autopsy specimens have confirmed the ability of the technique to identify lipid-rich thin-cap fibroatheromas through blood. A catheter-based system has been developed to address the challenges-of access to the coronary artery, blood, motion, and the need to scan-that must be overcome for use in patients. Initial clinical experience in six patients with stable angina demonstrates that high-quality NIR spectra can be safely obtained. Additional studies are planned to validate the ability of the technique to identify lipid-rich coronary artery plaques and ultimately link chemical characterization with subsequent occurrence of an acute coronary syndrome.

Beyond low-density lipoprotein: addressing the atherogenic lipid triad in type 2 diabetes mellitus and the metabolic syndrome

The metabolic syndrome and type 2 diabetes mellitus are both becoming more prevalent, and both increase the risk of cardiovascular disease. Many patients are not receiving appropriate treatment for the type of dyslipidemia that commonly occurs in these disorders--the so-called 'atherogenic lipid triad' of high serum triglyceride levels, low serum high-density lipoprotein cholesterol (HDL-C) levels, and a preponderance of small, dense, low-density lipoprotein cholesterol (LDL-C) particles. All of the processes involved in atherogenesis can be exacerbated by insulin resistance and/or the metabolic syndrome. Hypertriglyceridemia is a strong predictor of coronary heart disease. There is also an inverse relationship between serum levels of HDL-C and triglycerides in diabetic patients, with low serum HDL-C levels possibly representing an independent risk factor for cardiovascular disease. Small, dense, LDL-C particles are also highly atherogenic as they are more likely to form oxidized LDL and are less readily cleared. Insulin resistance, which is central to the metabolic syndrome and type 2 diabetes mellitus, leads to high levels of very low-density lipoprotein (VLDL), which contain a high concentration of triglycerides, resulting in high serum triglyceride levels and low serum HDL-C levels. Even though modification of the atherogenic lipid triad is probably one of the most effective methods of reducing cardiovascular risk, therapy for diabetic dyslipidemia is often directed to first lowering serum LDL-C levels with a HMG-CoA reductase inhibitor. This may leave substantial excess risk for cardiovascular disease in patients with these types of dyslipidemia. The results of recent trials evaluating HMG-CoA reductase inhibitors have been mixed, with two showing no significant effect on cardiovascular outcomes in subgroups of diabetic patients. The recent CARDS (Collaborative Atorvastatin Diabetes Study) showed that atorvastatin can reduce cardiovascular events in a trial specifically designed for a diabetic population, though the population had to have at least one other risk factor in addition to diabetes mellitus. Fibric acid derivatives, such as fenofibrate, bezafibrate and gemfibrozil, are potentially well suited to the treatment of dyslipidemia that is generally associated with type 2 diabetes mellitus and the metabolic syndrome, as they are usually more effective than HMG-CoA reductase inhibitors for normalizing serum levels of HDL-C and triglycerides. Promising results have been obtained from several trials of fibric acid derivatives including the BIP (Bezafibrate Infarction Prevention) study and the VA-HIT (Veterans Affairs Cooperative Studies Program HDL-C Intervention Trial; gemfibrozil). The FIELD (Fenofibrate Intervention and Event Lowering in Diabetes) trial, a clinical outcomes trial specifically designed to evaluate fenofibrate in a large population of patients with type 2 diabetes mellitus, many of whom have the metabolic syndrome, is underway. The FIELD trial results should shed light on the efficacy and safety of fenofibrate in reducing cardiovascular morbidity in diabetic and metabolic syndrome patients and on the safety profile of combination therapy with fenofibrate and a HMG-CoA reductase inhibitor.

Glucose, insulin, and potassium for metabolic support in acute myocardial infarction: is the jury still out?

During ischemic and cardiomyopathic conditions, carbohydrate (glucose) metabolism in cardiomyocytes predominates over use of free fatty acids. The shift to glucose metabolism is a physiologic response to ischemia, which in many patients, particularly diabetics or those who are insulin-resistant, is blunted. Free fatty acid metabolism during ischemia produces higher levels of lactate and hydrogen ions within the ischemic cells. This in turn degrades myocardial contractility, induces diastolic dysfunction, and reduces the arrhythmogenic threshold of the cardiomyocyte. Suppression of free fatty acid uptake and oxidation by any means will increase myocardial glucose substrate utilization in ischemia. Theoretically, then, an insulin-glucose solution that can augment GLUT-1 and GLUT-4 translocation to the sarcolemmal membrane can assist cardiomyocyte survival during ischemia; however, study results have not supported metabolic therapy. It is essential for any investigation of glucose, insulin, potassium therapy to separate out the effect of hyperglycemia and glucose toxicity to make any meaningful comment on the effectiveness of metabolic support in myocardial infarction.

Retroperitoneal hemorrhage from inferior epigastric artery: Value of femoral angiography for detection and management

Laceration of the inferior epigastric artery during cardiac catheterization is under-reported in the literature, but it is a serious complication leading to retroperitoneal hemorrhage and even death. We report on two cases of retroperitoneal bleeding from unintentional puncture of the inferior epigastric artery during cardiac catheterization. Femoral angiography is a valuable tool to promptly recognize this complication.

Myocardial Infarction as a Presentation of Clinical In-Stent Restenosis

BACKGROUND

In-stent restenosis is considered to be a gradual and progressive condition and there is scant data on myocardial infarction (MI) as a clinical presentation.

METHODS AND RESULTS

Of 2,462 consecutive patients who underwent percutaneous coronary intervention between June 2001 and December 2002, clinical in-stent restenosis occurred in 212 (8.6%), who were classified into 3 groups: ST elevation MI (STEMI), non-ST elevation MI (NSTEMI) and non-MI. Of the 212 patients presenting with clinical in-stent restenosis, 22 (10.4%) had MI (creatine kinase (CK)>or=2xbaseline with elevated CKMB). The remaining 190 (89.6%) patients had stable angina or evidence of ischemia by stress test without elevation of cardiac enzymes. Median interval between previous intervention and presentation for clinical in-stent restenosis was shorter for patients with MI than for non-MI patients (STEMI, 90 days; NSTEMI, 79 days; non-MI, 125 days; p=0.07). Diffuse in-stent restenosis was more frequent in MI patients than in non-MI patients (72.7% vs 56.3%; p<0.005). Renal failure was more prevalent in patients with MI than in those without MI (31.8% vs 6.3%, p=0.001). Compared with the non-MI group, patients with MI were more likely to have acute coronary syndromes at the time of index procedure (81.8% vs 56.8%, p=0.02).

CONCLUSION

Clinical in-stent restenosis can frequently present as MI and such patients are more likely to have an aggressive angiographic pattern of restenosis. Renal failure and acute coronary syndromes at the initial procedure are associated with MI.

Prevalence of newly diagnosed diabetes in clinical settings

A substantial number of patients being evaluated or treated for cardiovascular disease are found to have glucometabolic disorders. Identification of such patients is important because treatment for coronary artery disease and stroke needs to be individualized. Hyperglycemia on admission or during hospitalization regardless of whether diabetes mellitus is known to exist in these patients is associated with increased morbidity and mortality. Despite the fact that this has been known for some time, various strategies to reduce hyperglycemia have had mixed results in cardiac outcomes. Another important factor is that a new diagnosis of diabetes mellitus in these patients should result in the patient's triage to appropriate healthcare professionals to optimize glycemic control. The prevalence of hyperglycemia in patients admitted with acute cardiovascular disease and the effect of hyperglycemia on outcome are reviewed.