Seven-year outcome in the Bypass Angioplasty Revascularization Investigation (BARI) by treatment and diabetic status

Long-term follow-up after invasive approach of coronary artery disease in daily practice

BACKGROUND

To assess long-term survival in unselected patients with coronary artery disease in who an invasive approach is considered.

METHODS

All patients with significant coronary artery disease who were presented for coronary revascularisation to two tertiary centres in 1992 were included. Follow-up data were collected in September 2002. Multivariate Cox' proportional-hazards regression analysis was applied to assess the independent relation between variables and 10-year survival.

RESULTS

A total of 877 patients were included in this analysis. Mean age was 62 and the most common clinical diagnosis was chronic stable angina (60%). Diabetes was present in 12% of the patients. During the follow-up period, 233 patients (27%) died. Predictors of long-term survival were increasing age, diabetes, peripheral vascular disease and a decreased left ventricular function. Compared to medical treated patients, those treated with revascularisation (either by PCI or CABG) had a decreased long-term mortality (p<0.05). Of the patients with PCI 27% had died, compared to 24% in those who had CABG and 36% of those who were treated medically. However, after adjusting for differences in baseline variables, conservative treatment was no significant predictor of long-term mortality. After multivariable analyses, increasing age, decreased left ventricular function and diabetes were independent predictors of long-term mortality.

CONCLUSIONS

In patients with coronary artery disease in whom an invasive approach is considered, increasing age, impaired left ventricular function and diabetes are the strongest predictors of long-term mortality. After adjustments for differences in baseline variables, invasive treatment is not associated with a lower long-term mortality.

Differences in the association between type 2 diabetes and impaired microvascular function among Europeans and African Caribbeans

AIMS/HYPOTHESIS

Diabetes is associated with microvascular damage in all populations, but diabetic patients of Black African descent (African Caribbeans) have a greater risk of vascular target organ damage than would be anticipated for any given blood pressure level. We investigated whether this may be due to differences in the microvasculature.

MATERIALS AND METHODS

To assess the maximum hyperaemic response to heating and the post-ischaemic response, Laser Doppler fluximetry was performed on 51 and 100 Europeans, and on 66 and 88 African Caribbeans with and without diabetes, respectively. Subjects were aged between 40 and 65 years and recruited from the general population. Echocardiographic interventricular septal thickness (IVST) was measured as a proxy for vascular target organ damage.

RESULTS

In diabetic subjects of both ethnic groups, the maximum hyperaemic response and peak response to ischaemia were attenuated as compared to the corresponding non-diabetic subjects (p=0.08 for diabetic and 0.03 for non-diabetic Europeans; p=0.03 and 0.1 for African Caribbeans). Adjustment for cardiovascular risk factors, in particular insulin and blood pressure, abolished these differences in Europeans (p=0.8 for diabetic and 0.2 for non-diabetic Europeans), but not in African Caribbeans (p=0.03 and 0.05).

CONCLUSIONS/INTERPRETATION

Persisting microvascular dysfunction in African Caribbeans may contribute to the increased risk of target organ damage observed in diabetes in this population. The weak contribution of conventional cardiovascular risk factors to these disturbances indicates that conventional therapeutic interventions may be less beneficial in these patients. There was a risk-factor-independent, inverse association between IVST and maximal hyperaemia. These ethnic differences in microvascular responses to temperature and arterial occlusion could account for increased target organ damage in African Caribbeans.

Integrated Management of Patients with Diabetes Mellitus and Ischemic Heart Disease: PCI, CABG, and Medical Therapy

Modern coronary revascularization strategies are based on studies performed in the 1970s and 1980s that compared coronary artery bypass surgery with standard medical therapy available at the time. Studies comparing surgical and percutaneous revascularization followed, demonstrating similar long-term outcome among thousands of randomized patients. The largest of these trials, the Bypass Angioplasty Revascularization Investigation (BARI), cast doubt on the generalizability of these findings to all subgroups, finding that patients with diabetes mellitus and multivessel disease had worse long-term outcome with an initial strategy of percutaneous transluminal coronary angioplasty (PTCA). Indeed, patients with diabetes mellitus are at increased risk for cardiovascular morbidity and mortality, while the benefit of standard therapies in these patients is attenuated by the underlying metabolic abnormalities and significant comorbidities associated with the diabetic state. However, surgical and percutaneous revascularization techniques continue to evolve. Similarly, modern medical therapy is markedly superior to that available during these early studies, with demonstrable benefit in primary and secondary prevention of vascular events in both diabetic and nondiabetic patients. Ongoing trials will define the impact of current treatment modalities in this important and growing population.

Screening for coronary artery disease in patients with diabetes: a Bayesian strategy of clinical risk evaluation and exercise echocardiography

OBJECTIVE

Screening for coronary artery disease is constrained by its low prevalence in unselected patients. We compared the ability of clinical scores to identify a high-risk group with diabetes mellitus and investigated a Bayesian strategy by combination with exercise echocardiography (ExE).

METHODS

The Framingham risk score (FRS), a score based on the American Diabetes Association (ADA) screening guidelines, the United Kingdom Prospective Diabetes Study (UKPDS) risk engine, and a disease-specific diabetic cardiac risk score (DCRS) were calculated in 199 asymptomatic patients with type 2 diabetes mellitus undergoing ExE. The frequency of abnormal ExE and the proportion of these with coronary stenoses were sought in groups designated as high risk on the basis of optimal cutoffs for each score. All patients were followed up for 1 year.

RESULTS

High risk was identified in fewer patients with the DCRS (27%) than FRS (38%, P = .02), ADA (41%, P = .004), and UKPDS (43%, P = .001). Exercise echocardiography was positive in 27 (14%); 11 of 23 proceeding to angiography showed significant stenoses. Areas under the receiver operator characteristic curves for prediction of a positive ExE were similar for DCRS, UKPDS, and FRS but less for ADA (P = .04). Positive ExE was uncommon in low-risk patients (8%-11%) and most were false positives (58%-80%). Cardiovascular events (n = 9) were more likely in the high-risk compared with the low-risk UKPDS (9% vs 2%, P = .03) and DCRS (12% vs 2%, P = .01).

CONCLUSION

Combination of the UKPDS or DCRS with ExE may optimize detection of coronary artery disease and cardiac events in asymptomatic patients, while minimizing the numbers of ExE and false-positive rate.

Management of patients with type 2 diabetes after acute coronary syndromes

Acute coronary syndromes are associated with a high risk for subsequent major cardiovascular events and with a risk for mortality that remains substantially increased for many months following the acute phase. Patients with type 2 diabetes mellitus are especially vulnerable and encounter excessive long-term mortality. Effective management of patients with type 2 diabetes following acute coronary syndromes requires aggressive multidisciplinary efforts for reduction of several risk factors, including meticulous control of blood glucose. The evidence for different medication and treatment strategies capable of improving the outcomes is reviewed and the currently available recommendations are summarised.

Sirolimus-eluting stent implantation in diabetic patients with multivessel coronary artery disease

BACKGROUND

Restenosis rate is lower after sirolimus-eluting stent (SES) implantation than after bare metal stent (BS) implantation. We evaluated the impact of SES implantation on immediate and 12-month outcome in diabetic patients with multivessel coronary artery disease (MVD).

METHODS

From April 2002 to September 2003, 100 consecutive diabetic patients with MVD without previous myocardial revascularization underwent successful elective percutaneous coronary intervention (PCI) with SES on native coronary arteries at our institutions. A group (n = 122) of consecutive diabetic patients with MVD treated with BS implantation (BS group) for de novo lesions was selected from our database and matched with the SES group. Major adverse cardiac events (MACEs) during hospital stay and at follow-up included nonfatal myocardial infarction, death, bypass surgery, and re-PCI.

RESULTS

At 12 +/- 4 months, MACEs occurred in 25% of patients in the SES group and in 44% of those in the BS group (P = .003, OR .72, 95% CI 0.57-0.91). Need for repeat intervention (re-PCI or bypass surgery) occurred in 17% of patients in the SES group and in 41% of those in the BS group (P < .001, OR .67, 95% CI 0.52-0.86). No significant difference in the rate of death and myocardial infarction was observed. In the SES group, the independent predictors of MACEs at follow-up were premature clopidogrel discontinuation (hazard ratio 20.62, 95% CI 1.60-264.97, P = .020) and chronic renal insufficiency (hazard ratio 4.73, 95% CI 1.99-11.25, P = .0004).

CONCLUSIONS

As compared with BS implantation, SES implantation favorably influences outcome in diabetic patients with MVD, mainly by reducing the need for new revascularization.

Percutaneous coronary intervention for chronic total occlusions: the Thoraxcenter experience 1992-2002

AIMS

Chronic total occlusions (CTOs) are commonly found on diagnostic angiography, and there is some evidence from one study that successful percutaneous revascularization leads to an improvement in long-term survival rates. However, this study included patients treated for unstable angina with short-duration occlusion, and stent implantation was utilized in only 7%. We re-evaluated the long-term outcomes of a large consecutive series of patients with a CTO of >1-month duration treated at our centre, with stent implantation utilized in the majority.

METHODS AND RESULTS

All patients treated with percutaneous coronary intervention (PCI) between 1992 and 2002 were retrospectively identified from a dedicated database. A total of 874 consecutive patients were treated for 885 CTO lesions. Mean follow-up time was 4.47 +/- 2.69 years (median 4.10 years). Patients were evaluated for the occurrence of major adverse cardiac events (MACE) comprising death, acute myocardial infarction, and need for repeat revascularization with either coronary artery bypass surgery or PCI. Successful revascularization was achieved in 576 lesions (65.1%), in which stent implantation was used in 81.0%. At 30 days, the overall MACE rate was significantly lower in those patients with a successful recanalization (5.5 vs. 14.8%, P < 0.00001). At 5 years, survival was significantly higher in those patients with a successful revascularization (93.5 vs. 88.0%, P = 0.02). In addition, there was a significantly higher survival free of MACE (63.7 vs. 41.7%, P < 0.0001), with the majority of events reflecting the need for repeat intervention. Independent predictors for survival were successful revascularization, lower age, and the absence of diabetes mellitus and multivessel disease.

CONCLUSION

Successful percutaneous revascularization of a CTO leads to a significantly improved survival rate and a reduction in major adverse events at 5 years. Most events relate to the need for repeat reintervention, and the introduction of drug-eluting stents, with low-restenosis rates, encourages the development of technologies to improve recanalization success rates. However, failed recanalization may be associated acutely with an adverse event, and new technologies must focus on a safe approach to successful recanalization.

One-year outcomes of coronary artery bypass graft surgery versus percutaneous coronary intervention with multiple stenting for multisystem disease: A meta-analysis of individual patient data from randomized clinical trials

BACKGROUND

We aimed to provide a quantitative analysis of the 1-year clinical outcomes of patients with multisystem coronary artery disease who were included in recent randomized trials of percutaneous coronary intervention with multiple stenting versus coronary artery bypass graft surgery.

METHODS

An individual patient database was composed of 4 trials (Arterial Revascularization Therapies Study, Stent or Surgery Trial, Argentine Randomized Trial of Percutaneous Transluminal Coronary Angioplasty Versus Coronary Artery Bypass Surgery in Multivessel Disease 2, and Medicine, Angioplasty, or Surgery Study 2) that compared percutaneous coronary intervention with multiple stenting (N = 1518) versus coronary artery bypass graft surgery (N = 1533). The primary clinical end point of this study was the combined incidence of death, myocardial infarction, and stroke at 1 year after randomization. Secondary combined end points included the incidence of repeat revascularization at 1 year. All analyses were based on the intention-to-treat principle.

RESULTS

After 1 year of follow-up, 8.7% of patients randomized to percutaneous coronary intervention with multiple stenting versus 9.1% of patients randomized to coronary artery bypass graft surgery reached the primary clinical end point (hazard ratio 0.95 and 95% confidence interval 0.74-1.2). Repeat revascularization procedures occurred more frequently in patients allocated to percutaneous coronary intervention with multiple stenting compared with coronary artery bypass graft surgery (18% vs 4.4%; hazard ratio 4.4 and 95% confidence interval 3.3-5.9). The percentage of patients who were free from angina was slightly lower after percutaneous coronary intervention with multiple stenting than after coronary artery bypass graft surgery (77% vs 82%; P = .002).

CONCLUSIONS

One year after the initial procedure, percutaneous coronary intervention with multiple stenting and coronary artery bypass graft surgery provided a similar degree of protection against death, myocardial infarction, or stroke for patients with multisystem disease. Repeat revascularization procedures remain high after percutaneous coronary intervention, but the difference with coronary artery bypass graft surgery has narrowed in the era of stenting.

Long-term benefits and limitations of combined antianginal drug therapy in elderly patients with symptomatic chronic coronary artery disease

BACKGROUND

Chronic angina is a common and disabling disorder in the elderly. Combined antianginal drug treatment represents the mainstay of therapy in this population. However, there is a paucity of data regarding the effect of this strategy on long-term outcome in the elderly.

METHODS

To assess the long-term effect of combined antianginal drug therapy in elderly individuals, we performed a long-term follow-up analysis of all 148 patients of the Trial of Invasive versus Medical therapy in Elderly (TIME) patients with chronic symptomatic coronary-artery disease assigned to an optimized medical therapy strategy. Angina severity, measures of quality of life (QOL), and survival were assessed after a median of 3.7 (0.1-6.9) years.

RESULTS

At baseline, patients were 79.8 +/- 3.5 years old with Canadian Cardiovascular Society (CCS) class angina 3.0 +/- 0.7 despite the use of 2.4 +/- 0.6 antianginal drugs. Although antianginal drugs were increased to 2.8 +/- 0.9 (P < .01), 63 (43%) patients needed revascularization for refractory symptoms during the first year of observation (REVASC). At baseline, REVASC patients had more frequently CCS class 4 angina (37% vs 20%, P < 0.05) but reported less prior heart failure (5% vs 20%, P < 0.01), fewer prior cerebral events (3% vs 13%, P < .05) and a lower rate of two or more comorbidities (10% vs 33%, P < .01) than patients on continued drug therapy (DRUG). At long-term follow-up, angina severity was still higher in DRUG compared to REVASC patients (CCS class, 1.8 +/- 1.6 vs 1.0 +/- 1.4, P < .05) despite more antianginal drugs (2.1 +/- 1.1 vs 1.5 +/- 1.0, P < .01), whereas measures of QOL had improved similarly in both groups. In addition, long-term mortality was significantly higher in DRUG than in REVASC patients (38% vs 13%, P < .01).

CONCLUSION

Combined antianginal drug therapy successfully relieved symptoms in most elderly patients with chronic angina but failed to do so in 43%. Patients who needed revascularization for refractory symptoms reported less angina, despite lower drug use during long-term follow-up and had a better long-term survival. Thus, the widely used strategy to increase antianginal drug therapy in elderly patients instead of evaluating them for revascularization should be reconsidered.

13-year follow-up of the German angioplasty bypass surgery investigation

AIMS

The German Angioplasty Bypass Surgery Investigation was designed to compare symptomatic efficacy and safety of percutaneous coronary balloon angioplasty (PTCA) with coronary artery bypass surgery (CABG) in patients with symptomatic multi-vessel disease. This follow-up study was performed to determine the long-term outcome of patients following these interventions.

METHODS AND RESULTS

From 1986 to 1991, 359 patients with angina CCS class II-IV, age below 75 years, and coronary multi-vessel disease requiring revascularization of at least two major coronary vessels were recruited at eight German centres and randomized to PTCA or CABG. From 337 patients undergoing the planned procedure, 324 patients could be followed-up (96%). Baseline parameters were identical in both groups, 2.2+/-0.6 vessels were treated in CABG patients, whereas 1.9+/-0.5 vessels were treated in PTCA patients. Thirty-seven per cent of surgical patients received internal mammary artery grafts, while no stents were used in patients undergoing PTCA. At the end of the 13-year follow-up period, the degree of angina, the degree of dyspnea, and the utilization of nitrates were comparable in both groups. With a total number of 76 deaths, Kaplan-Meier analysis revealed a comparable distribution in both groups. Although time to first re-intervention was significantly shorter in the PTCA group, P<0.001, frequencies of re-intervention (CABG, n=94; PTCA, n=136) and crossover rates (CABG to PTCA, n=49; PTCA to CABG, n=51) were comparable in both groups.

CONCLUSION

The results of our 13-year follow-up suggest that in patients with symptomatic multi-vessel disease, both PTCA and CABG are associated with a comparable long-term survival and symptomatic efficacy. How far these results may be altered by developments such as drug-eluting stents or off-pump surgery remains to be determined.

Percutaneous coronary intervention versus coronary artery bypass grafting in diabetic patients

Revascularization with CABG or angioplasty in diabetic patients is associated with a less favor-able outcome. The value of early intervention will be assessed in the ongoing BARI 2D trial. It remains to be determined whether the widespread use of GP IIb/IIIa drugs and prolonged dual antiplatelet therapy in diabetic patients who receive stents, and possibly drug-eluting stents, will alter results significantly so that outcomes become comparable or even better than CABG (Fig. 3). It seems prudent to consider CABG with LIMA grafting in diabetic patients who have severe multi-vessel disease and to consider angioplasty in selected patients who have more discrete and less severe disease.

Late Outcome After Stenting or Coronary Artery Bypass Surgery for the Treatment of Multivessel Disease: A Single-Center Matched-Propensity Controlled Cohort Study

BACKGROUND

Although several randomized controlled trials examined the relative benefits of coronary artery bypass graft (CABG) surgery and percutaneous coronary intervention (PCI), the most appropriate treatment remains a matter of debate, at least in some subsets of patients. Therefore, we evaluated the 8-year outcome after multivessel stent implantation (stent group) or coronary artery bypass surgery (CABG group) in a single-center propensity-matched cohort study.

METHODS

The stent study population consisted of all 409 consecutive patients who underwent an elective coronary intervention between 1995 and 1999 in whom at least 2 stents were implanted in multiple vessels. They were matched by using the propensity score method with 409 CABG patients of 1,723 CABG patients with multivessel disease who underwent elective CABG in the same period of time. The two populations were very different before matching. After matching, the CABG population resembled a stent population.

RESULTS

The cumulative survival rates after stent were 93%, 90%, and 82% at, respectively, 3, 5, and 8 years; and after CABG 97%, 93%, and 87% (p = 0.02). This was caused mainly by patients with left main disease (p = 0.03). Event-free survival was only 70%, 68%, and 64% after stent and 89%, 82%, and 78% after CABG at, respectively, 3, 5, and 8 years (p < 0.0001). After adjusting, stent was an independent predictor of higher mortality.

CONCLUSIONS

In this matched cohort study with an 8-year follow-up, survival was better and less repeat revascularizations were needed among patients undergoing elective CABG for the treatment of multivessel disease as compared with the stent group.

Role of insulin secretagogues and insulin sensitizing agents in the prevention of cardiovascular disease in patients who have diabetes

In the absence of clinical trial evidence to compare the secretagogues with sensitizers, it is difficult to make recommendations about which class of drug is more important to prescribe for the prevention of cardiovascular disease in diabetes mellitus. Epidemiologic data supports insulin resistance as a major factor in cardiovascular disease through a variety of mechanisms. Because sensitizers improve insulin sensitivity and correct many of the vascular abnormalities that are associated with insulin resistance, it is tempting to suggest that they may be superior for this purpose. Conversely, meeting the goals that are recommended for glycemia also are important and achieving them may not be always possible with sensitizers, particularly in the later stages of the disease when insulin levels are not high,despite insulin resistance. In such situations,combination therapy may be needed with both types of drugs. No data are available on the cardiovascular effects of such combinations;some retrospective data suggest a possibility of increased events with the combination of sulfonylureas and metformin. Thus, further prospective studies in this area are necessary.

Use of myocardial perfusion imaging to predict the effectiveness of coronary revascularisation in patients with stable angina pectoris

PURPOSE

Coronary revascularisation is the treatment of choice in patients with stable angina who have significant stenoses. From a pathophysiological point of view, however, mitigation of angina is to be expected only in the presence of reversible ischaemia. Therefore it was the aim of this study to examine the effect of revascularisation on stable angina in relation to the myocardial perfusion imaging (MPI) pattern prior to intervention.

METHODS

Three hundred and eighty-four patients (58.0+/-8.8 years) referred for angiography underwent MPI. Prior to MPI and at 2-year follow-up, patients were classified as having typical angina, atypical angina, non-cardiac chest pain or no pain, and the severity of chest pain was graded according to the Canadian Cardiovascular Society (CCS) criteria. The patients themselves estimated their pain on a visual analogue scale. Management was based on symptoms and angiographic findings, since the results of MPI were not communicated.

RESULTS

Among the 240 patients who were not revascularised, 79% had typical or atypical angina at study entrance versus 40% at follow-up. In comparison, 93% of the 144 revascularised patients had typical or atypical angina before intervention versus only 36% at follow-up. This additional advantage of invasive therapy was present only in patients with reversible defects; revascularisation had no additional effect in patients with normal perfusion or irreversible defects. Similarly, additional, significant reductions in CCS class and visual analogue score were observed exclusively in patients with reversible defects.

CONCLUSION

In patients referred for coronary angiography owing to known or suspected stable angina, revascularisation was significantly more effective than medical treatment exclusively in patients with reversible ischaemia.

Prognostic value of I-123 15-(p-iodophenyl)-3-(R,S) methylpentadecanoic acid myocardial imaging in patients with known or suspected coronary artery disease

BACKGROUND

Although iodine 123 15-(p-iodophenyl)-3-(R , S) methylpentadecanoic acid (BMIPP) can assess abnormal utilization of fatty acid in the diseased myocardium, the prognostic value of BMIPP imaging at rest in patients with known or suspected coronary artery disease (CAD) remains unclear.

METHODS AND RESULTS

A total of 270 patients were included by a retrospective search of the existing databases of 4 institutions. In addition to hard events, consisting of cardiac death and nonfatal myocardial infarction, any significant events including death, nonfatal myocardial infarction, coronary revascularization, heart failure, and unstable angina were assessed. During a median follow-up of 3.9 years, 33 patients had significant events, among whom 10 had hard events. Kaplan-Meier survival estimates revealed a hard event-free survival rate of 98% at 3 years in patients with a BMIPP defect score lower than 5 but 93% in those with a defect score of 5 or greater ( P = .03). With regard to significant events, the analysis showed an event-free survival rate of 92% at 3 years in patients with a BMIPP defect score lower than 5 but 80% in those with a defect score of 5 or greater ( P = .0003).

CONCLUSIONS

These results indicate that resting BMIPP imaging has prognostic value and may have a role in the risk stratification of patients with known or suspected CAD.

Single-photon emission computed tomography myocardial perfusion imaging in patients with diabetes

Diabetes mellitus has reached epidemic proportions, creating a large population of people at increased risk for cardiac events. Single-photon emission computed tomography myocardial perfusion imaging (SPECT MPI) provides an effective tool to accurately diagnose and risk stratify patients with diabetes, similar to patients without diabetes. Diabetics, however, are at increased risk for coronary events. Diabetics with normal MPI have increased late cardiac events, and even those with mild perfusion defects have increased event rates compared with nondiabetics with similar perfusion abnormalities. Stress MPI can provide valuable risk stratification data for both sexes, with or without diabetes. However, diabetes appears to exert a greater relative impact in women than in men. Despite the absence of symptoms, the incidence and prevalence of coronary artery disease is increased in patients with diabetes. Further studies and research will be needed to define the eventual role of SPECT MPI in asymptomatic diabetics.

Diabetes mellitus and heart failure: basic mechanisms, clinical features, and therapeutic considerations

Diabetic cardiomyopathy encompasses the spectrum from subclinical disease to the full-blown syndrome of congestive heart failure. The prevalence of type 2 diabetes mellitus is increasing at an alarming rate in the western world. and with it, the frequency of diabetes-related heart failure. There is at least early suggestion that target-driven, long-term, intensified intervention that is aimed at multiple risk factors in patients who have type 2 diabetes and microalbuminuria may reduce the risk of macrovascular (cardiovascular) and micro-vascular complications by approximately 50%. Thus, it is imperative that patients, particularly those who are at risk for the cardiovascular dysmetabolic syndrome, be screened aggressively for the presence of glucose intolerance and diabetes. When detected, all metabolic and cardio-vascular parameters should be evaluated and treated aggressively to reach currently recommended clinical targets. Such action will result in great benefit for patients by reducing morbidity and mortality and improving quality of life and will reduce the financial burden that is associated with this epidemic disease.

Survival After Coronary Revascularization Among Patients With Kidney Disease

BACKGROUND

The optimal approach to revascularization in patients with kidney disease has not been determined. We studied survival by treatment group (CABG, percutaneous coronary intervention [PCI], or no revascularization) for patients with 3 categories of kidney function: dialysis-dependent kidney disease, non-dialysis-dependent kidney disease, and a reference group (serum creatinine <2.3 mg/dL).

METHODS AND RESULTS

Data were derived from the Alberta Provincial Project for Outcomes Assessment in Coronary Heart Disease (APPROACH), which captures information on all patients undergoing cardiac catheterization in Alberta, Canada. Characteristics and patient survival in 662 dialysis patients (1.6%) and 750 non-dialysis-dependent kidney disease patients (1.8%) were compared with the remainder of the 40,374 patients (96.6%). For the reference group, the adjusted 8-year survival rates for CABG, PCI, and no revascularization (NR) were 85.5%, 80.4%, and 72.3%, respectively (P<0.001 for CABG versus NR; P<0.001 for PCI versus NR). Adjusted survival rates were 45.9% for CABG, 32.7% for PCI, and 29.7% for NR in the nondialysis kidney disease group (P<0.001 for CABG versus NR; P=0.48 for PCI versus NR) and 44.8% for CABG, 41.2% for PCI, and 30.4% for NR in the dialysis group (P=0.003 for CABG versus NR; P=0.03 for PCI versus NR).

CONCLUSIONS

Compared with no revascularization, CABG was associated with better survival in all categories of kidney function. PCI was also associated with a lower risk of death than no revascularization in reference patients and dialysis-dependent kidney disease patients but not in patients with non-dialysis-dependent kidney disease. The presence of kidney disease or dependence on dialysis should not be a deterrent to revascularization, particularly with CABG.

Medical Costs and Quality of Life 10 to 12 Years After Randomization to Angioplasty or Bypass Surgery for Multivessel Coronary Artery Disease

BACKGROUND

Coronary bypass surgery (CABG) and angioplasty (PTCA) have been compared in several randomized trials, but data about long-term economic and quality-of-life outcomes are limited.

METHODS AND RESULTS

Cost and quality-of-life data were collected prospectively from 934 patients who were randomized in the Bypass Angioplasty Revascularization Investigation (BARI) and followed up for 10 to 12 years. CABG had 53% higher costs initially, but the gap closed to <5% during the first 2 years; after 12 years, the mean cumulative cost of CABG patients was 123,000 dollars versus 120,750 dollars for PTCA, yielding a cost-effectiveness ratio of 14,300 dollars/life-year added. CABG patients experienced significantly greater improvement in their physical functioning for the first 3 years but not in later follow-up. Recurrent angina substantially reduced all quality-of-life measures throughout follow-up. Cumulative costs were significantly higher among patients with diabetes, heart failure, and comorbid conditions and among women; costs also were increased by angina, by the number of revascularization procedures, and among patients who died.

CONCLUSIONS

Early differences between CABG and PTCA in costs and quality of life were no longer significant at 10 to 12 years of follow-up. CABG was cost-effective as compared with PTCA for multivessel disease.

Preprocedural C-Reactive Protein Is Not Associated with Angiographic Restenosis or Target Lesion Revascularization after Coronary Artery Stent Placement

Background: We assessed the predictive value of preprocedural plasma C-reactive protein (CRP) concentrations and statin therapy on 6 months angiographic and 1-year clinical outcome after nonurgent coronary stent placement.

Methods and Results: Baseline plasma high-sensitivity CRP concentrations were prospectively measured in 345 patients undergoing elective stent placement in a native coronary artery. The binary angiographic in-stent restenosis (ISR; stenosis ≥50% of vessel diameter) rate was 19% in patients with CRP values within the reference interval (≤3 mg/L) and 22% in patients with CRP &gt;3 mg/L [odds ratio (OR) = 1.2; 95% confidence interval (CI), 0.73–2.09]. Statin therapy in a univariate analysis significantly reduced both angiographic and clinical ISR rates. Multivariate logistic regression analysis identified unstable angina, smoking, and stent length, but neither CRP concentration nor statin therapy as independent predictors for angiographic ISR. Patients with an abnormal CRP value showed a trend toward a higher risk of nonfatal myocardial infarction (3.8% vs 0.5%; OR = 7.43; 95% CI, 0.87–61.65). Target lesion revascularization rates did not differ between the two groups (9.6% vs 10.6%; OR = 1.13; 95% CI, 0.56–2.28). In multivariate analysis, male sex (OR = 0.44, 95% CI, 0.19–0.97) and statin therapy (OR = 0.26; 95% CI, 0.09–0.68) were independent predictors for the occurrence of target lesion revascularization.

Conclusions: This study demonstrated a lack of association between preprocedural plasma CRP concentrations and angiographic coronary ISR or clinically driven target lesion revascularization. Patients with an abnormal CRP concentration showed a trend toward higher risk of nonfatal myocardial infarction during 1 year of follow-up. Statin therapy was independently associated with decreased clinically driven target lesion revascularization, underlining the beneficial effects of statins on clinical outcome.

Cardiovascular disease and chronic kidney disease: insights and an update

Despite the high prevalence and significant morbidity and mortality rates of chronic kidney disease (CKD) related to cardiovascular disease, it remains vastly understudied. Most of the current practice recommendations come from small under-powered prospective studies, retrospective reviews, and assuming patients with CKD will similarly benefit from medications and treatments as patients with normal renal function. In addition, because of the previous lack of a consistent definition of CKD and how to measure renal function, definitions of the degree of renal dysfunction have varied widely and compounded the confusion of these data. Remarkably, despite patients with CKD representing the group at highest risk from cardiovascular complications, even greater than patients with diabetes mellitus, there has been a systematic exclusion of patients with CKD from therapeutic trials. This review outlines our current understanding of CKD as a cardiovascular risk factor, treatment options, and the future directions that are needed to treat cardiovascular disease in patients with CKD.

Comparison of bilateral thoracic artery grafting with percutaneous coronary interventions in diabetic patients

BACKGROUND

This study compares the outcome of percutaneous coronary interventions (PCI) with bilateral internal thoracic grafting (BITA) in diabetic patients.

METHODS

From May 1996 to December 1999, 802 consecutive diabetic patients underwent myocardial revascularization: 363 by PCI and 439 by BITA. The two groups were similar; however, left main disease (28% versus 3.3%), ejection fraction less than 0.35 (14.5% versus 5.5%), and chronic obstructive lung disease (8.4% versus 3%) were more prevalent in the BITA group, and prior percutaneous transluminal coronary angioplasty, in the PCI group (16.8% versus 10.5%).

RESULTS

The number of coronary vessels treated per patient was higher in the BITA group (3.4 versus 1.2; p < 0.001). Thirty-day mortality was similar: 3.4% in the BITA group and 2.8% in the PCI group. Late follow-up (3 to 6.5 years) showed decreased return of angina (11% versus 64%; p < 0.001), fewer reinterventions (2.7% versus 55%; p < 0.001), and increased cardiovascular event-free survival (80% versus 30%; p < 0.001) in the BITA group. Six-year survival of BITA and PCI patients was 85.5% and 81.2%, respectively (not significant). However, survival of the subgroups of patients with left main or three-vessel coronary artery disease was significantly better with BITA (86% versus 76%; p = 0.003).

CONCLUSIONS

Despite higher risk profile of diabetic patients treated surgically by BITA, their late outcome is better than that of patients treated by PCI. The results of this study support referring diabetics with single-vessel or double-vessel disease to PCI and those with three-vessel and left main coronary artery disease to surgery.

Detection of silent myocardial ischemia in asymptomatic diabetic subjects: the DIAD study

OBJECTIVE

To assess the prevalence and clinical predictors of silent myocardial ischemia in asymptomatic patients with type 2 diabetes and to test the effectiveness of current American Diabetes Association screening guidelines.

RESEARCH DESIGN AND METHODS

In the Detection of Ischemia in Asymptomatic Diabetics (DIAD) study, 1,123 patients with type 2 diabetes, aged 50-75 years, with no known or suspected coronary artery disease, were randomly assigned to either stress testing and 5-year clinical follow-up or to follow-up only. The prevalence of ischemia in 522 patients randomized to stress testing was assessed by adenosine technetium-99m sestamibi single-photon emission-computed tomography myocardial perfusion imaging.

RESULTS

A total of 113 patients (22%) had silent ischemia, including 83 with regional myocardial perfusion abnormalities and 30 with normal perfusion but other abnormalities (i.e., adenosine-induced ST-segment depression, ventricular dilation, or rest ventricular dysfunction). Moderate or large perfusion defects were present in 33 patients. The strongest predictors for abnormal tests were abnormal Valsalva (odds ratio [OR] 5.6), male sex (2.5), and diabetes duration (5.2). Other traditional cardiac risk factors or inflammatory and prothrombotic markers were not predictive. Ischemic adenosine-induced ST-segment depression with normal perfusion (n = 21) was associated with women (OR 3.4). Selecting only patients who met American Diabetes Association guidelines would have failed to identify 41% of patients with silent ischemia.

CONCLUSIONS

Silent myocardial ischemia occurs in greater than one in five asymptomatic patients with type 2 diabetes. Traditional and emerging cardiac risk factors were not associated with abnormal stress tests, although cardiac autonomic dysfunction was a strong predictor of ischemia.

Ischemic heart disease and congestive heart failure in diabetic patients

Ischemic heart disease and heart failure are major contributors to the morbidity and mortality associated with diabetes mellitus. With growing knowledge of how the metabolic derangements of diabetes contribute to the pathogenesis of cardiovascular disease, we must continuously refine our understanding of optimal screening and strategies for prevention and treatment for these interlinked disorders. This article summarizes our current understanding of ischemic heart disease and heart failure in patients with diabetes mellitus, highlighting gaps in our knowledge about the relationship between diabetes and cardiovascular disease. Special consideration is given to new strategies for treating the adverse effects of abnormal glucose metabolism on the cardiovascular system.

Impact of diabetes on outcome following isolated minimally invasive bypass grafting of the left anterior descending artery

BACKGROUND

The outcome in patients treated by conventional coronary artery bypass grafting (CABG) for coronary artery disease is negatively influenced by the presence of diabetes. The relative effect of diabetes in patients undergoing isolated minimally invasive revascularization of the left anterior descending artery (LAD) using the internal thoracic artery (ITA) has as yet not specifically been looked at. Thus, this study sought to evaluate the impact of diabetes on mid-term outcome following minimally invasive coronary artery bypass grafting (MIDCAB).

METHODS

From 1996 to 1999, 411 patients received a MIDCAB procedure at our institution and were now followed up. In this study population there were 63 diabetic patients (15.3%) and 348 nondiabetic patients (84.7%). Isolated proximal stenoses or an occlusion of the LAD were present in 262 patients (63.7%), whereas 149 (36.3%) had multi-vessel disease (MVD) at the time of the MIDCAB procedure. The clinical outcome was evaluated by questionnaires sent to the patients and their physicians.

RESULTS

The mean follow-up was 29.4 +/- 11.1 months. The incidence of myocardial infarction was significantly higher in diabetics as compared to nondiabetics (9.5% vs 3.2%, p = 0.034). Diabetics and nondiabetics had similar rates of subsequent revascularization procedures during follow-up. Cumulative total survival of diabetic and nondiabetic patients was not statistically different. The 3-year cardiac mortality was however significantly higher in diabetic than in nondiabetic patients if MVD was initially present (Kaplan-Meier estimate: 10.7% vs 2.5%, relative risk [RR] = 5.5, p = 0.017 by log-rank test). The 3-year cardiac mortality in diabetic and nondiabetic patients with isolated disease of the LAD (single vessel disease [SVD]) was not significantly different. After adjustment of baseline characteristics by Cox regression analysis the 3-year risk of cardiac death was significantly higher in the diabetic group (RR = 1.82, CI 95%:1.2 to 3.3, p = 0.045).

CONCLUSIONS

The results support diabetes to be an independent risk factor for outcome in patients with MVD undergoing a MIDCAB procedure in analogy to those undergoing CABG procedures. Diabetics with isolated disease of the LAD, however, benefit out of proportion from this treatment modality.

Bilateral versus single internal thoracic artery grafting in oral-treated diabetic subsets: comparative seven-year outcome analysis

BACKGROUND

Recent interest has focused on the use of arterial conduits in diabetic subsets. To date, the long-term benefits of bilateral internal thoracic artery (BITA) grafting in this subgroup remain in question.

METHODS

Two hundred eighty-five consecutive oral-treated diabetics operated on nonemergent basis (1996 to 1998) were compared according to the surgical technique, left-sided skeletonized BITA (n = 228) or single internal thoracic artery- saphenous veins (SITA) (n = 57). Patients with chronic lung disease, usually preselected to SITA grafting, were not included.

RESULTS

The respective grafts to patient ratio was 3.1 +/- 1 and 3.2 +/- 0.8 for the SITA and BITA groups (p = NS). Complementary conduits used in the BITA group were gastroepiploic arteries (25%) and saphenous veins (13%). Early outcome was comparable, including the incidence of deep sternal infections (1.8% in both groups). During follow-up (range, 4 to 7.5 years; median, 5), there were less repeat revascularizations (4.4% vs 12.3%, p = 0.025) and major adverse cardiac events (MACE) (11.2% vs 36.8%, p < 0.0001) in the BITA group. At 7 years, survival (Kaplan-Meier) (75% vs 59%, p = 0.006, log-rank), freedom from cardiac mortality (92% vs 68%, p < 0.0001), and freedom from MACE (70% vs 59%, p = 0.004) were superior in the BITA group. Multivariate analysis identified the use of BITA as a protective factor against the occurrence of late cardiac mortality (odds ratio [OR] 0.2) and MACE (OR 0.3); conversely, SITA-saphenous vein arrangements increased the risk by fivefold (OR 5, confidence interval limits [CL] 1.6 to 16.6, p = 0.005) and threefold (OR 3.3, CL 1.5 to 9, p = 0.005), respectively.

CONCLUSIONS

Left-sided BITA grafting confers improved long-term survival and event-free survival in oral-treated diabetics. We, therefore, recommended this approach in this diabetic subset.

Long-Term Outcome of Renal Transplant Recipients in the United States After Coronary Revascularization Procedures

Background— Retrospective studies in dialysis patients have reported increased survival after coronary artery bypass (CAB) compared with coronary artery stenting and PTCA. The purpose of this study was to compare the long-term outcome of renal transplant recipients after stent, PTCA, or CAB with or without internal mammary grafting (CAB [IMG+] or CAB [IMG−]).

Methods and Results— Renal transplant recipients hospitalized from 1995 to 1999 for first coronary revascularization procedure were retrospectively identified from the United States Renal Data System database. Event-free survival for the end points of all-cause death, cardiac death, acute myocardial infarction (AMI), and the combined end point of cardiac death or AMI was estimated by the life-table method. The impact of independent predictors on survival was examined in a comorbidity-adjusted Cox model. In-hospital mortality rate was 2.3% for 909 stent patients, 4.3% for 652 PTCA patients, 9.4% for 288 CAB (IMG−) patients, and 5.0% for 812 CAB (IMG+) patients. Two-year all-cause survival (±SE) was: stent, 82.5±2.8%; PTCA, 81.6±3.1%; CAB (IMG−), 74.4±5.4%; and CAB (IMG+), 82.7±2.8%. The relative risks of all-cause and cardiac death were not significantly different among revascularization groups. The relative risk of cardiac death or AMI (versus PTCA) was 0.90 (95% CI, 0.69 to 1.17) for stent, 0.80 (95% CI, 0.55 to 1.17) for CAB (IMG−), and 0.57 (95% CI, 0.42 to 0.76) for CAB (IMG+).

Conclusions— Renal transplant recipients in the United States have comparable long-term survival after percutaneous and surgical coronary revascularization procedures. The most favorable long-term outcome occurs after surgical coronary revascularization.

Anticipated impact of drug-eluting stents on referral patterns for coronary artery bypass graft surgery: a population-based angiographic analysis

OBJECTIVES

To determine the clinical and angiographic characteristics of patients who underwent coronary artery bypass graft (CABG) surgery before the availability of drug-eluting stents (DES) and to project the potential impact of percutaneous coronary intervention using DES.

PATIENTS AND METHODS

We reviewed the coronary angiograms obtained between March 1999 and December 2001 of 192 consecutive patients from Olmsted County, Minnesota, who had undergone isolated CABG surgery for the first time. Three interventional cardiologists categorized the patients into 1 of 4 groups on the basis of technical feasibility of complete revascularization by percutaneous coronary intervention with DES.

RESULTS

The study population consisted primarily of men (78%), with a mean age of 67 years. Of the 192 patients, 58 (30%) had diabetes mellitus, and 124 (65%) had 3-vessel disease. Twelve patients (6%) had lesions suitable for stents that matched the inclusion criteria for DES in recently published trials; 77 (40%) had lesions suitable for stents but had lesion characteristics not included in the initial DES trials. Thirty-two patients (17%) had target lesions considered technically difficult, but feasible, for stent placement. Seventy-one patients (37%) had lesions unsuitable for percutaneous coronary intervention (75% of these due to chronic occlusions) with the current stent delivery technology.

CONCLUSION

This population-based analysis suggests that only a small proportion of patients undergoing CABG surgery meets the strict angiographic eligibility criteria for DES on the basis of recent trials. However, up to 46% of current CABG patients may ultimately undergo conversion to DES. The remaining 54% of this patient population may still not be ideal candidates for DES with the current stent delivery technology.

Propensity Analysis of Long-Term Survival After Surgical or Percutaneous Revascularization in Patients With Multivessel Coronary Artery Disease and High-Risk Features

Background— Although most randomized clinical trials have suggested that long-term survival rates after percutaneous coronary intervention (PCI) or surgical multivessel coronary revascularization (CABG) are equivalent, some post hoc analyses in high-risk groups and adjustment for severity of coronary disease have suggested higher mortality after PCI.

Methods and Results— We studied 6033 consecutive patients who underwent revascularization in the late 1990s. PCI was performed in 872 patients; 5161 underwent CABG. Half the patients had significant left ventricular dysfunction or diabetes. Propensity analysis to predict the probability of undergoing PCI according to 22 variables and their interactions was used. The C-statistic for this model was 0.90, indicating excellent discrimination between treatments. There were 931 deaths during 5 years of follow-up. The 1- and 5-year unadjusted mortality rates were 5% and 16% for PCI and 4% and 14% for CABG (unadjusted hazard ratio, 1.13; 95% CI, 1.0 to 1.4; P =0.07). PCI was associated with an increased risk of death (propensity-adjusted hazard ratio, 2.3; 95% CI, 1.9 to 2.9; P <0.0001). This difference was observed across all categories of propensity for PCI and in patients with diabetes or left ventricular dysfunction. Other independent predictors of mortality ( P ≤0.01 for all) were renal dysfunction, age, diabetes mellitus, chronic lung disease, peripheral vascular disease, left main trunk stenosis, and extent of coronary disease (Duke angiographic score).

Conclusions— In patients with multivessel coronary artery disease and many high-risk characteristics, CABG was associated with better survival than PCI after adjustment for risk profile.

Bilateral internal thoracic artery grafting in diabetic patients: short-term and long-term results of a 515-patient series

BACKGROUND

Despite potential long-term benefits, bilateral internal thoracic artery grafting in diabetics remains controversial because of the risk of sternal infection. We sought to assess the short- and long-term outcome after left-sided bilateral internal thoracic artery grafting and to determine the configuration of choice in diabetic subsets.

METHODS

Between 1996 and 2001, 515 diabetics underwent isolated left-sided skeletonized bilateral internal thoracic artery grafting. The outcome of 468 consecutive oral-treated diabetics and 47 selective insulin-treated patients was analyzed. Patients undergoing T-grafting were compared with those undergoing in situ bilateral internal thoracic artery arrangements.

RESULTS

The respective rates for early mortality and sternal infections were 2.4% and 1.9% in oral-treated diabetics and 6.3% and 4.3% in insulin-treated diabetics. Multivariate correlates of sternal infection were chronic lung disease (odds ratio, 10), obesity (odds ratio, 7), reoperation (odds ratio, 22), and a creatinine level of 2 mg/dL or more (odds ratio, 8). Five-year survival was 82%. The T-graft (n = 437) and in situ (n = 162) subgroups had comparable baseline profiles. Freedom from cardiac mortality at 6.5 years was 95.6% and 87.6% (P =.277), and freedom from repeat revascularization was 91.5% and 92.7% (P =.860), respectively. The choice of bilateral internal thoracic artery configuration did not appear as a correlate of mortality, cardiac mortality, or major adverse cardiac events. Complementary right-sided gastroepiploic artery (hazard ratio, 0.36) and sequential (hazard ratio, 0.55) grafting were identified as protective factors against the occurrence of major adverse cardiac events.

CONCLUSIONS

Routine skeletonized bilateral internal thoracic artery grafting can be implemented safely in oral-treated diabetics. This strategy is associated with a favorable late cardiac outcome and is thus recommended. Both left-sided bilateral internal thoracic artery configurations provide comparable short- and long-term outcomes.

Glucose-insulin-potassium solution improves left ventricular energetics in chronic ovine diabetes

BACKGROUND

Therapeutic modulation of myocardial metabolism improves outcomes in diabetic patients following myocardial infarction and coronary artery surgery. However, the mechanism of this beneficial effect has not been fully elucidated. This study evaluated the effect of glucose-insulin-potassium solution (GIK) on left ventricular (LV) energetics and oxygen utilization efficiency in a chronic ovine model of diabetes.

METHODS

Diabetes was induced in sheep with streptozotocin. Experiments were performed following 12 months untreated diabetes (n = 6) and in controls (n = 6). Open-chest anesthetized sheep were instrumented to determine the LV pressure-volume relationship, oxygen consumption, and free fatty acid uptake. Glucose-insulin-potassium was infused at 1.5 mL x kg(-1) x h(-1) for 60 minutes and assessment repeated.

RESULTS

Glucose-insulin-potassium decreased LV free fatty acid uptake in control: 0.090 +/- 0.047 microg/beat/100 g to 0.024 +/- 0.022 microg/beat/100 g, p = 0.02 and diabetes: 0.33 +/- 0.32 microg/beat/100 g to 0.11 +/- 0.13 microg/beat/100 g, p = 0.04. Similarly, GIK decreased unloaded left ventricular oxygen consumption (LVVO(2)) in both control (0.42 +/- 0.05 to 0.37 +/- 0.13J/beat/100 g, p < 0.001) and diabetic sheep (0.40 +/- 0.24 to 0.23 +/- 0.23J/beat/100 g, p < 0.001). The slope of the LVVO(2)-pressure-volume area relation (contractile efficiency) was unchanged in either group. Glucose-insulin-potassium improved LV contractility 58% +/- 37% (p = 0.005) and stroke work efficiency 18% +/- 10% (p = 0.009) in diabetic animals but not controls. Therefore, oxygen utilization efficiency (stroke work-LVVO(2)) increased only in diabetic animals (16.6% +/- 4.8% to 26.9% +/- 3.6%, p = 0.002) following GIK.

CONCLUSIONS

This study provides in vivo evidence that GIK improves LV energetics in diabetes. Oxygen utilization efficiency is improved as a result of improved stroke work efficiency and decreased unloaded LVVO(2). Improved efficiency of oxygen utilization provides a physiologic rationale for the beneficial effect of GIK in diabetic patients.

Three-Year Outcome After Coronary Stenting Versus Bypass Surgery for the Treatment of Multivessel Disease

Background— The primary results of Arterial Revascularization Therapy Study reported a greater need for repeated revascularization after percutaneous coronary intervention with stenting (PCI). However, PCI was less expensive than coronary artery bypass grafting (CABG) and offered the same degree of protection against death, stroke, and myocardial infarction.

Methods and Results— Patients with multivessel disease (n=1205) were randomly assigned to either CABG or PCI and followed up for up to 3 years. Survival rates without stroke or myocardial infarction were similar in each group at 1 year and 3 years (90.5% versus 91.4% for PCI versus CABG at 1 year and 87.2% versus 88.4% for PCI versus CABG at 3 years). However, the respective repeat revascularization rates were 21.2% and 26.7% at 1 and 3 years in patients allocated to PCI, compared with 3.8% and 6.6% in patients allocated to CABG ( P <0.0001). Diabetes ( P <0.0009) and maximal pressure for stent deployment ( P <0.002) are the strongest independent predictors of events at 3 years after PCI, whereas left anterior descending coronary artery grafting ( P <0.006) is the best predictor of event-free survival at 3 years after CABG. The incremental cost of surgery compared with PCI for an event-free patient was 19 257 at 1 year but decreased to 10 492 at 3 years. It remained at 142 391 at 3 years when revascularization procedures were excluded in the efficacy end point, however.

Conclusions— Three-year survival rates without stroke and myocardial infarction are identical in both groups, and the cost/benefit ratio of stenting is determined primarily by the increasing need for revascularization in the PCI group.

Management of the patient with diabetes mellitus and myocardial infarction: clinical trials update

The increasing prevalence of diabetes mellitus and its association with cardiovascular disease have become serious public health issues. Although diabetes and coronary artery disease (CAD) may have different clinical manifestations, their atherosclerotic burden and prognosis are quite similar. However, patients with diabetes who have underlying CAD have a different, more complex pathophysiology and a worse prognosis. Optimal management of these patients requires a comprehensive multifactorial approach to prevent microvascular and macrovascular events. In the setting of an acute myocardial infarction (MI), immediate management should focus on limiting infarct size. This can be achieved by using fibrinolytic agents, primary percutaneous intervention (in ST-segment elevation MI), or glycoprotein IIb/IIIa inhibitors followed by coronary angiography within 24 to 48 hours and, when appropriate, by coronary intervention (in non-ST-segment elevation MI). Drug-eluting stents may have an important role in patients with diabetes, who have a higher rate of postintervention coronary restenosis than do nondiabetic individuals. In addition, all patients with an acute MI (ST- and non-ST-segment elevation) should be given aspirin, nitrates, beta-blockers, and angiotensin-converting enzyme (ACE) inhibitors. The long-term pharmacologic management after MI is similar in all patients, regardless of the initial presentation. Antiplatelet agents (aspirin and/or clopidogrel), ACE inhibitors, beta-blockers, lipid-lowering agents, and glycemic control have all been shown to be effective in decreasing long-term mortality. Despite advances in the management of MI, the mortality rates of patients with diabetes remain 1.5- to 2-fold greater than those of persons without diabetes. Maximizing the use of lifesaving therapies proved effective in large randomized clinical trials and tight metabolic control can further decrease mortality rates. However, many of these lifesaving therapies are underused in patients with diabetes because of the misconception that potential adverse effects may outweigh their benefits. New programs aimed at improving postinfarction quality of care in patients with diabetes, based on guidelines and expert recommendations, have shown promise. However, more effort must be devoted to the improvement of outcomes related to these public health problems.

Percutaneous coronary intervention: historical perspectives, current status, and future directions

In the twenty-six years since Gruntzig introduced a simple balloon angioplasty technique, percutaneous coronary intervention has undergone extraordinary growth and has now surpassed bypass surgery in frequency of performance. Several critical breakthrough technologies account for this remarkable progress: intracoronary stents have increased success rates and reduced restenosis, adjunctive antiplatelet therapy has reduced periprocedural complications, and restenosis after stent placement has been effectively treated with local radiation. Most recently, drug-eluting stents coated with cell-cycle inhibitors have shown great promise for further reducing restenosis, possibly to negligible levels.

Clinical and Angiographic Predictors of Restenosis After Stent Deployment in Diabetic Patients

Background— Restenosis and consequent adverse cardiac events are increased in diabetics undergoing percutaneous coronary intervention. Use of intracoronary stents may ameliorate such risks; however, factors influencing the likelihood of restenosis after stent deployment in this high-risk patient subgroup are unknown.

Methods and Results— We retrospectively analyzed all stented diabetic patients in 16 studies of percutaneous coronary intervention, all of which underwent core angiographic analysis at Cardialysis, Rotterdam. Univariate and multivariate analyses, with 37 clinical and angiographic variables, compared those with and without restenosis and predicted restenosis rates calculated through the use of reference charts derived from angiographic data. Within the studies, 418 of 3090 (14%) stented patients with 6-month angiographic follow-up had diabetes. Restenosis (≥50% diameter stenosis at follow-up) occurred in 550 of 2672 (20.6%) nondiabetic and 130 of 418 (31.1%) diabetic patients ( P <0.001). Univariate predictors of restenosis in diabetics were smaller vessel reference diameter (RD) ( P <0.001), smaller minimal luminal diameter before stenting ( P =0.01), smaller minimal luminal diameter and percent diameter stenosis after stenting ( P <0.001, P =0.04), greater stented length of vessel ( P <0.001), and reduced body mass index (BMI) ( P =0.04). With the use of multivariate analysis, only smaller RD ( P =0.003), greater stented length of vessel ( P =0.04), and reduced BMI ( P =0.04) were associated with restenosis. Reference charts demonstrated an incremental risk of restenosis that appears solely dependent on vessel RD.

Conclusions— Restenosis after stent deployment is significantly increased in diabetic patients. Vessel caliber, stented length of vessel, and lower BMI are predictors of in-stent restenosis in patients with diabetes. Furthermore, vessel caliber affected the predicted risk of restenosis incrementally.

Paradigm shifts in cardiovascular medicine

Cardiovascular medicine is changing rapidly with the development, testing, and introduction of new diagnostic and therapeutic methods. New interventional techniques such as the use of drug-eluting stents have important implications for the care of individual patients and the delivery and economics of health care in general. Drug-eluting stents have been shown to improve outcomes among patients undergoing percutaneous coronary intervention by significantly reducing restenosis rates. Two randomized trials have documented that per 100 patients treated with the sirolimus drug-eluting stent, 12.5 to 13.6 patients avoided the need for subsequent target lesion revascularization, when compared with patients treated with conventional stents. The economic effect of the introduction of these stents, which are projected to be two to three times as expensive as conventional stents, is complex and depends on which segment of health care is considered. These stents will be favorably received by patients, physicians, employers, and society as well as payers. However, hospitals may be adversely affected by having increased procedural costs for the stents, along with fewer procedures for evaluation and treatment of restenosis and probably decreased surgical volumes. Drug-eluting stents are only the first of many new technologic advances that will affect cardiovascular care. These procedures have many features in common, including: 1). replacement of major surgical procedures with less invasive approaches; and 2). redistribution of costs, with a decrease in hospital profits but potentially lower costs of health care delivery for society as a whole.

Stent restenosis and the use of drug-eluting stents in patients with diabetes mellitus

Stents have become the technique of choice for percutaneous revascularization, but in-stent restenosis has remained a clinical challenge. This brief article summarizes the incidence, patterns, and proposed mechanisms of restenosis and outlines its contemporary management with specific focus on the diabetic patient. It includes a synopsis of the strategy of drug-eluting stents, which is the most recent and major advance in percutaneous coronary intervention.