Long-term rates of cardiovascular events in patients with the metabolic syndrome according to severity of coronary-angiographic alterations.

OBJECTIVES: To assess the long-term risk of mortality and cardiovascular events, related to metabolic syndrome (MetS), in patients with less, or more severe coronary artery disease (CAD). METHODS: One thousand and eighty patients were divided in four groups, according to severity of CAD (1=less than 50% or nonsignificant stenoses; 2=greater or significant stenoses), and according to MetS (A=no; B=yes). Risk was evaluated with the Cox regression analysis. RESULTS: About 18.9% of patients had less and 81.1% more advanced CAD. MetS was present in 45.1% of the first, and in 52.9% of the second group. At baseline, patients with MetS, or significant stenoses, had less favorable medical, biochemical, and angiographic characteristics. During a follow-up of 12.6+/-3.4 years, group 1B had higher incidence (16.3 vs. 7.1%) and hazard ratio [2.36 (1.001-5.57; P=0.0497)] of myocardial infarction than group 1A; group 2B had a higher incidence (19.0 vs. 11.7%) and hazard ratio [1.67 (1.18-2.37; P=0.0041)] of stroke than group 2A. Groups 2A and 2B, as compared with groups 1A and 1B, had a higher incidence of myocardial infarction (39.1 vs. 7.1; 41.8 vs. 16.3%); group 2B had higher incidence of stroke than group 1B (19.0 vs. 9.8%). After adjustment for common risk factors, group 2B retained an elevated risk of stroke. After additional adjustment for diabetes, no event was significantly related to MetS. CONCLUSION: At baseline, coronary patients with MetS, or significant angiographic alterations, had more cardiovascular risk factors. During follow-up, both MetS and significant CAD increased the risk of cardiovascular morbidity but not of mortality.

Effect of cholesterol lowering and cardiovascular risk factors on the progression of aortoiliac arteriosclerosis: a quantitative cineangiography study.

The post-Coronary Artery Bypass Graft (Post-CABG) trial has shown that aggressive compared to moderate lowering of low-density lipoprotein cholesterol (LDL-C) delayed the progression of obstructive disease in aortocoronary saphenous vein grafts and in the left main coronary artery. Patients had been allocated to high-and low-dose lovastatin therapy for a 4-5 year period. The present study evaluated the effect of LDL-C lowering and the role of cardiovascular risk factors on the progression of arteriosclerosis in the distal abdominal aorta and common iliac arteries. From one of the participating centers of the post-CABG trial, 145 patients who had adequate imaging of the aortoiliac arteries at baseline and follow-up were included. Angiographic outcomes, presumed to reflect progression of arteriosclerosis and obtained from lumen diameter (LD) measurements using quantitative cineangiography, were as follows: significant decrease of the minimum lumen diameter (LD) and increase of the maximum LD, percent lumen stenosis, and percent lumen dilatation. These outcomes were not significantly less frequent in patients randomly allocated to aggressive compared to moderate LDL-C lowering. Of 9 cardiovascular risk factors, only 2 were significantly related to progression of aortoiliac arteriosclerosis. Current smoking predicted both percent lumen stenosis increase and, to a lesser degree, percent lumen dilatation increase (p = 0.010 and p = 0.055, respectively). Abnormally high body mass index (BMI > or = 25 kg/m2) correlated with percent lumen dilatation increase (p = 0.006). Aggressive compared to moderate LDL-C lowering did not prevent or delay the progression of aortoiliac arteriosclerosis. Smoking predicted both lumen narrowing and dilatation presumably caused by arteriosclerosis. Abnormally high BMI, reflecting overweight or obesity, was strongly associated with vessel dilatation.

Quality of life after coronary artery bypass graft: results from the POST CABG Trial.

OBJECTIVES: The POST CABG (Post Coronary Artery Bypass Graft) Trial showed that aggressive lowering of low-density lipoprotein (LDL) cholesterol levels reduced the progression of atherosclerosis in saphenous vein grafts. In the extended follow-up phase, aggressive lowering of LDL cholesterol levels was associated with reduced rates of clinical events. Low-dose anticoagulation therapy did not reduce the progression of atherosclerosis. We conducted this analysis to determine the effects of both lipid-lowering and low-dose anticoagulation therapy on health-related quality of life (HRQL). DESIGN: Randomized clinical trial, factorial design. SETTING: Outpatients in five tertiary care medical centers. PATIENTS: A cohort of 852 patients enrolled in the POST CABG Trial completed an HRQL questionnaire at baseline, and at the year 2 and year 4 follow-up visits. INTERVENTION: Aggressive LDL cholesterol lowering vs moderate LDL cholesterol lowering, and low-dose warfarin vs placebo. MEASUREMENTS: Domains included emotional status, basic physical and social functioning, perceived health status, symptoms of pain, a variety of physical symptoms, and global life satisfaction. RESULTS: Overall, there were no indications of systematic differences among treatment groups for any of the HRQL parameters at baseline, year 2, or year 4. CONCLUSIONS: These data indicate that patients did not experience detrimental or beneficial effects on HRQL parameters while receiving LDL cholesterol-lowering therapy that had demonstrable benefits for treatment of atherosclerosis.

Effect of increasing metabolic syndrome score on atherosclerotic risk profile and coronary artery disease angiographic severity.

The metabolic syndrome (MS) is a frequent cause of coronary artery disease (CAD), and recently the National Cholesterol Education Program Adult Treatment Panel III suggested its diagnosis in the presence of 3 to 5 quantitatively defined markers. Because the consequences of the MS are likely related to the number and diversity of markers, we studied the relation between the number of markers-the MS score-and the degree of abdominal obesity, risk factor profile, and severity of CAD. One thousand one hundred eight subjects of a mostly white population with symptoms of CAD (793 men and 315 women; 58.1 +/- 9.8 years of age) were divided into 6 groups based on their MS scores. A low high-density lipoprotein cholesterol level was the most frequently observed marker, followed by increased blood pressure, triglycerides, waist circumference, and fasting glucose. As the MS score increased so did abdominal obesity, parameters of "nontraditional" dyslipidemia with surrogate markers of dense low-density lipoprotein and high-density lipoprotein particles, blood pressure, fasting glucose, insulin, and the homeostatic model assessment insulin resistance index. Similarly, an increasing MS score was significantly related to more severe coronary angiographic alterations and higher frequencies of unstable angina, myocardial infarction, percutaneous coronary intervention, and coronary artery bypass grafting. Therefore, the MS score provides a clinically useful index of MS severity and the associated atherosclerotic risk factor profile. It also correlates with the angiographic severity of CAD and its clinical complications.

Incidence, coronary risk profile and angiographic characteristics of prediabetic and diabetic patients in a population with ischemic heart disease.

BACKGROUND: Recently, the threshold of fasting blood glucose indicating diabetes mellitus was lowered to 7.00 mmol/L (126 mg/dL) and the term 'impaired fasting glucose' (IFG; fasting blood glucose ranging from 6.11 mmol/L to 6.99 mmol/L or from 110 mg/dL to 126 mg/dL) was introduced to define a prediabetic state. OBJECTIVE: To evaluate the incidence of the above states in a Canadian population with suspected coronary artery disease and to compare their risk profiles and angiographic status to normoglycemic subjects. PATIENTS AND METHODS: Revision of the database of 1108 consecutive patients (793 males and 315 females; mean age 58.1+/-9.8 years) undergoing clinical, biochemical and elective angiographic studies because of suspected coronary artery disease. RESULTS: One third of the patients had either IFG (8.5%), or were diabetics (24.2%). Unlike the 747 normoglycemic patients, both IFG (n=94) and diabetic (n=267) subjects showed an insulin resistance profile, with abdominal obesity, and dislipidemia characterized by high triglycerides in the presence of low high density lipoprotein-cholesterol and high normal or elevated blood pressure. Both prediabetics and diabetics had a significantly higher homeostatic model assessment insulin resistance index than normoglycemics (P<0.0001), the index also being higher for diabetics than for prediabetics (P<0.0001). Coronary atherosclerosis was documented in most patients of the three groups and was significantly more severe in diabetics than in IFG patients (P=0.0359) or normoglycemics (P=0.0069), with no differences between the former two groups. CONCLUSIONS: As expected, the new definitions identify more patients with impaired homeostasis than earlier criteria. IFG patients have similar coronary risk profile as diabetics, suggesting the need for similar coronary precautions.

Incidence and clinical characteristics of the metabolic syndrome in patients with coronary artery disease.

BACKGROUND AND OBJECTIVES: Several studies suggested that the insulin resistance-associated metabolic syndrome (MS) is a major risk factor for coronary artery disease (CAD), but the criteria to identify MS were only recently standardized by the National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP) III. METHODS: We evaluated the incidence of the newly defined MS in patients with documented CAD and compared the characteristics of patients with and without this syndrome. RESULTS: In a Canadian population with CAD (793 men and 315 women, age 58.1+/-9.8 years) 51% had MS. As compared to patients without the MS syndrome, these patients had significantly higher waist circumference, blood pressure levels and fasting glucose and triglyceride, but lower high-density lipoprotein (HDL)-cholesterol levels. Their homeostatic model assessment (HOMA) insulin resistance index was significantly higher, with indicators of highly atherogenic, small low-density lipoprotein (LDL) and HDL particles. Family history of diabetes and the use of hypoglycemic agents, beta-blockers and thiazides were more frequent, but physical exercise and alcohol consumption were less frequent in MS positive patients. Cumulative coronary stenosis score and the frequency of patients with >50% coronary artery narrowing were higher and there was a strong tendency for higher rates of previous myocardial infarction in MS positive patients. CONCLUSIONS: In a CAD population documented in 1991-1992, 51% of participants had MS and in several respects a more advanced coronary disease than those without the syndrome. These results support the view of NCEP ATP III, that in CAD prevention, beyond lowering LDL-cholesterol levels, interventions concerning the constituents of MS should be important.

Angiographic changes in saphenous vein grafts are predictors of clinical outcomes.

BACKGROUND: Previous studies have suggested that angiographic evidence of disease progression in coronary arteries increases the risk of subsequent coronary clinical events. This study ascertained whether patients enrolled in the Post Coronary Artery Bypass Graft Clinical Trial (POST CABG) who had substantial progression of atherosclerosis in >or=1 saphenous vein grafts (on the basis of assessment of baseline and follow-up angiograms obtained 4-5 years after study entry), but who had not reported clinical symptoms before follow-up angiography, were at a higher risk of subsequent events than patients who did not have substantial progression of atherosclerosis (decrease >or=0.6 mm in lumen diameter at site of greatest change from baseline). METHODS: All 1351 patients enrolled in the trial underwent baseline angiography; only the 961 patients who had follow-up angiography and no coronary events before the follow-up study were included in this analysis. The clinical center staff contacted patients to ascertain the events that had occurred after follow-up angiography (approximately 3.4 years later). RESULTS: Sixty-nine patients had died; 870 patients or relatives were interviewed, and 22 patients could not be contacted. Univariable estimates of relative risk associated with substantial progression ranged from 2.2 (P <.001) for cardiovascular death or nonfatal myocardial infarction to 3.3 (P <.001) for revascularization. Multivariable and univariable estimates of risk were similar. CONCLUSIONS: The findings provide evidence that patients who had substantial progression of atherosclerosis in vein grafts are at an increased risk for subsequent coronary events and suggest that angiographic changes in vein grafts are appropriate surrogate measures for clinical outcomes.

The Canadian Cardiovascular Society grading of angina pectoris revisited 30 years later.

BACKGROUND: The Canadian Cardiovascular Society (CCS) grading of angina pectoris was described in the medical literature in 1976. OBJECTIVES: To describe the origin of this grading, its worldwide acceptance, critiques, perceived limitations and alternative systems. METHODS: The present author, who chaired the CCS ad hoc committee that developed this grading system in 1972, used documentation based on personal correspondence, and information from medline and international citation indexes searches. RESULTS: The CCS committee's mandate was to standardize the definition of terms used in reporting studies of coronary artery disease and coronary artery bypass graft surgery. The committee defined a four-level system modelled on the New York Heart Association functional classification of patients with diseases of the heart, and the American Medical Association classes of organic heart diseases. Threshold activities that produced angina were detailed to assess reliably the severity of exertional angina by independent observers, and changes over time. The grading system has been cited over 650 times in the literature since its official publication in 1976. Although this grading system was found to be generally relevant and practical, several imperfections and potential limitations were reported, the most pertinent being the criterion "anginal syndrome may be present at rest" included in grade IV, which was found to be inappropriate and confusing. The prognostic significance of the grading system, despite the finding that this was not its primary goal, was also thought to be inadequate. CONCLUSION: Although this grading system of the severity of effort angina has been accepted throughout the world over the past 30 years, a revision is desirable considering its potential imperfections and inconsistencies with present day management of ischemic heart disease.