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In postmenopausal women with coronary artery disease, conjugated equine estrogen with or without continuous administration of medroxyprogesterone acetate has failed to slow the progression of atherosclerosis. Whether 17beta-estradiol (the endogenous estrogen molecule) alone or administered sequentially with medroxyprogesterone acetate can slow the progression of atherosclerosis is unknown.We conducted a double-blind, placebo-controlled trial in 226 postmenopausal women (mean age, 63.5 years) who had at least one coronary-artery lesion. Participants were randomly assigned to usual care (control group), estrogen therapy with micronized 17beta-estradiol alone (estrogen group), or 17beta-estradiol plus sequentially administered medroxyprogesterone acetate (estrogen-progestin group). In all patients the low-density lipoprotein (LDL) cholesterol level was reduced to a target of less than 130 mg per deciliter. The primary outcome was the average per-participant change between base-line and follow-up coronary angiograms in the percent stenosis measured by quantitative coronary angiography.After a median of 3.3 years of follow-up, the mean (+/-SE) change in the percent stenosis in the 169 participants who had a pair of matched angiograms was 1.89+/-0.78 percentage points in the control group, 2.18+/-0.76 in the estrogen group, and 1.24+/-0.80 in the estrogen-progestin group (P=0.66 for the comparison among the three groups). The mean difference in the percent stenosis between the estrogen group and the control group was 0.29 percentage point (95 percent confidence interval, -1.88 to 2.46), and the mean difference between the estrogen-progestin group and the control group was -0.65 (95 percent confidence interval, -2.87 to 1.57).In older postmenopausal women with established coronary-artery atherosclerosis, 17beta-estradiol either alone or with sequentially administered medroxyprogesterone acetate had no significant effect on the progression of atherosclerosis.

In the past year, new data have appeared on the long-term benefits of low-density lipoprotein apheresis in severely hypercholesterolemic patients who are refractory to lipid-lowering drug therapy. Such data are critical for clinical decision-making, because they confirm the hypothesis that the dramatic reduction in low-density lipoprotein made possible by this technique produces clear-cut clinical benefits. Because of its efficacy and low incidence of side-effects, apheresis for severe drug-refractory hypercholesterolemia has superseded surgical approaches, such as liver transplantation or ileal bypass.

Angiotensin-converting enzyme inhibitors have proven to be of clinical benefit in congestive heart failure. Whether they also provide benefit to patients with coronary artery disease in the absence of congestive heart failure via an antiatherosclerotic mechanism is a question the QUinapril Ischemic Event Trial quantitative coronary angiography (QCA) study attempted to answer: 1,750 patients with normal left ventricular function who were undergoing coronary angiography and angioplasty were randomized to 20 mg/day of quinapril versus placebo and followed for 3 years for cardiac end points. A randomly selected subgroup of the total cohort underwent follow-up angiography. The primary QCA end point was the categorical designation of progression versus nonprogression, defined either by QCA or by a cardiac event in patients selected for the QCA trial who had no usable follow-up x-ray film. Secondary end points in patients with 2 angiograms were: new stenosis development, change in minimum lumen diameter index, and change in percent diameter stenosis index. There were 119 progressors among 243 placebo-treated patients (49%) and 111 progressors among 234 quinapril-treated patients (47%) (p = NS). There were 44 patients with new stenosis developement in the placebo group (19%) and 50 (22%) in the quinapril group (p = NS). Change in minimum lumen diameter index was −0.21 ± 0.03 mm in the placebo group and −0.18 ± 0.03 mm in the quinapril group (p = NS). Finally, change in percent diameter stenosis index was +5.1 ± 1.0 in the placebo group and +3.5 ± 1.0 in the quinapril group (p = NS). Potential confounders of this trial are presented and discussed.

The QUinapril Ischemic Event Trial (QUIET) is the first prospective, double-blind, placebo-controlled trial to investigate the long-term antiatherosclerotic effects of angiotensin-converting enzyme inhibition. Normotensive, nonhyperlipidemic subjects (1,750) with normal left ventricular systolic function were randomly assigned to treatment or placebo at percutaneous transluminal coronary angioplasty (PTCA). The primary end point is time to first cardiac ischemic event. Baseline clinical characteristics are (mean +/- SD): age 58 +/- 9 years; blood pressure 123 +/- 15/74 +/- 10 mm Hg; low density lipoprotein cholesterol 124 +/- 27 mg/dL; high density lipoprotein cholesterol 37 +/- 10 mg/dL; and triglycerides 167 +/- 91 mg/dL. In addition, 81% are men; 22% are current smokers; 49% give a history of myocardial infarction. Baseline angiographic characteristics are (mean +/- SD): left ventricular ejection fraction 59% +/- 11%; per patient diameter stenosis (excluding the PTCA segment) 49% +/- 31%; 8.9 +/- 3.5 analyzable segments per patient (excluding the PTCA segment), 3.8 +/- 2.3 of which have visible stenosis. Including the PTCA segment, 52% have single vessel disease and 48% have multivessel disease. Baseline angiographic data for non-PTCA segments will be correlated with cardiac ischemic events which occur after 6 months. Up to 500 subjects will undergo follow-up angiography with quantitative coronary angiographic analysis (QCA) of baseline and follow-up films. The primary QCA end point will be per-patient categorical designation as progressor or nonprogressor based on the presence or absence of > or = 400 microns narrowing in > or = 1 vessels that did not undergo PTCA.

Angiotensin-converting enzyme inhibitors improve endothelial function, inhibit experimental atherogenesis, and decrease ischemic events. The Quinapril Ischemic Event Trial was designed to test the hypothesis that quinapril 20 mg/day would reduce ischemic events (the occurrence of cardiac death, resuscitated cardiac arrest, nonfatal myocardial infarction, coronary artery bypass grafting, coronary angioplasty, or hospitalization for angina pectoris) and the angiographic progression of coronary artery disease in patients without systolic left ventricular dysfunction. A total of 1,750 patients were randomized to quinapril 20 mg/day or placebo and followed a mean of 27 +/- 0.3 months. The 38% incidence of ischemic events was similar for both groups (RR 1.04; 95% confidence interval 0.89 to 1.22; p = 0.6). There was also no significant difference in the incidence of patients having angiographic progression of coronary disease (p = 0.71). The rate of development of new coronary lesions was also similar in both groups (p = 0.35). However, there was a difference in the incidence of angioplasty for new (previously unintervened) vessels (p = 0.018). Quinapril was well tolerated in patients after angioplasty with normal left ventricular function. Quinapril 20 mg did not significantly affect the overall frequency of clinical outcomes or the progression of coronary atherosclerosis. However, the absence of the demonstrable effect of quinapril may be due to several limitations in study design.

An understanding of how angiographic progression correlates with events is useful at this time for two reasons. First, to more fully comprehend the contribution of these trials in the past and second, to interpret trials which are currently underway or in the planning stages. A grave disservice has been done to the angiographic trials by introduction of the concept of “small angiographic change” leading to a “large reduction in events”. The former is due solely to the denominator effect and the latter was not generally seen, at lest in terms of the traditional endpoint of death from coronary disease plus non-fatal myocardial infarction. The predictive power of angiographic progression of future clinical events (its ability to serve as a “surrogate”) has been demonstrated during long term follow-up of three major angiographic trials. The success of sequential angiography to serve as a surrogate is probably based on the fact that angiography can detect plaque rupture. Thus angiographic trials could best be referred to as “plaque repture trails”.

Background Progression of coronary artery disease is assumed to be a surrogate end point for clinical coronary events. Because no single method or measure for a coronary angiographic end point is uniformly accepted as optimal, the utility and validity of surrogate end points for predicting clinical coronary events remain unsettled. Methods and Results The Cholesterol Lowering Atherosclerosis Study randomized 162 nonsmoking, 40- to 59-year-old men with previous coronary artery bypass graft surgery to colestipol/niacin plus diet or placebo plus diet. Atherosclerosis change on 2-year coronary angiograms was evaluated by a consensus panel and by quantitative coronary angiography (average per-subject change in percent diameter stenosis [%S] and minimum lumen diameter [MLD]). With all three end points, the benefit of colestipol/niacin treatment on coronary artery atherosclerosis has been reported. Annual follow-up for an average of 7 years (range, 6.3 months to 10 years) has been carried out on all subjects who completed the 2-year angiogram. Clinical coronary events (need for revascularization, nonfatal acute myocardial infarction, and coronary death) have been documented. Risk of clinical coronary events was positively related to coronary lesion progression for all three surrogate end points ( P P =.02) and progression of mild/moderate lesions (P P Conclusions In this population of nonsmoking men with previous bypass surgery, both the consensus panel– and quantitative coronary angiography–based end points of coronary artery disease progression predict clinical coronary events. Subjects who demonstrate greater coronary artery lesion progression have an increased risk of future clinical coronary events. Design of shorter, smaller trials of antiatherosclerotic agents is justified.

To assess the effects of lipid-lowering therapy with lovastatin on coronary angiographic findings in patients with coronary artery disease and to compare the findings with those of two lipid-lowering angiographic trials using similar end points.Randomized, double-blind, placebo-controlled, multicenter coronary angiographic trial.Community- and university-based cardiac catheterization laboratories.A total of 270 patients, 37 to 67 years old, with total cholesterol ranging from 4.92 to 7.64 mmol/L (190 to 295 mg/dL) and angiographically defined coronary artery disease.A cholesterol-lowering diet and either lovastatin, 80 mg/day, or placebo.Per-patient change in percent diameter stenosis as determined by quantitative coronary angiography (primary end point). Global change score, based on the consensus of blinded expert readers regarding angiographic change (secondary endpoint).Lovastatin lowered total cholesterol level by 32%, low-density lipoprotein cholesterol by 38%, and the apolipoprotein B by 26% and raised the high-density lipoprotein cholesterol by 8.5% (P0.001). Average percent diameter stenosis increased 2.2% in placebo recipients and 1.6% in lovastatin recipients (P0.20). For lesions 50% or greater, average percent diameter stenosis increased 0.9% in placebo recipients and decreased 4.1% in lovastatin recipients (P = 0.005). The mean global change score was +0.9 (indicating progression) in the placebo group and +0.4 in the lovastatin group (P = 0.002); 13 placebo recipients and 28 lovastatin recipients had global change scores indicating regression (P0.02).Treatment with lovastatin plus diet slows the rate of progression and increases the frequency of regression in coronary artery lesions (by global change score), especially in more severe lesions (by quantitative angiography). This is the third lipid-lowering trial to show a benefit using the global change score, an end point predictive of clinical coronary events. Differences between two of these trials, using quantitative coronary angiographic end points, may have theoretical bearing on the mechanisms by which lipid-lowering therapy operates at the level of the arterial wall.

A number of large-scale clinical trials have demonstrated that lipid-altering therapy is associated with a reduced risk of coronary artery disease events. The mechanism of benefit has been postulated to be related to favorable effects at the level of the arterial wall. Angiography allows direct examination of the effects of lipid-altering therapy on the arterial wall and extensive angiographic trial data are now available. Coronary angiographic trials, employing various patient populations, therapies and endpoint measures, have demonstrated slowed progression and increased regression of atherosclerosis in the coronary tree. Femoral artery trials (which might be considered as surrogate for coronary artery trials) have also shown significant regression of atherosclerosis in treated patients. There are pros and cons for all of the various atherosclerosis change measurement techniques, but coronary artery disease events remain the “bottom line” of concern. In this regard, the Program on the Surgical Control of the Hyperlipidemias (POSCH) trial is valuable since the 3-year human consensus panel-derived global coronary change score predicted subsequent coronary events. Yet to be determined are which quantitative coronary angiography measures predict events. Finally, given the number of therapeutic questions that remain, the most promising opportunity for future antiatherosclerosis research may lie in the use of ultrasound to evaluate changes in the carotid arteries.

The Cholesterol Lowering Atherosclerosis Study, a randomized, angiographic clinical trial, has demonstrated the beneficial effect of niacin/colestipol therapy on coronary and femoral atherosclerosis. The primary outcome was a panel-determined consensus score evaluating global coronary changes determined angiographically at 2 years. This article presents an evaluation of interreader agreement in independently assessing the status of native coronary arteries and overall coronary condition. Parameters include 1) identification of the presence of lesions and lesion changes; 2) estimation of lesion severity (percent stenosis) and amount of change in lesion severity; and 3) global assessment of change in coronary status. Readers independently agreed on 1) presence of lesions (82%) and change in lesions (51%); 2) percent stenosis +/- 10% (76%) and change in stenosis +/- 10% (81%); and 3) global assessment of change in coronary status within one step (96%). Results of these analyses may be useful in effectively designing angiographic trials that use a panel of human evaluators as well as computerized methods for angiographic interpretation.

Pregnancy in patients with severe hypercholesterolemia and coronary artery disease results in multiple problems both for mother and fetus; the most potent agents for low-density lipoprotein (LDL) cholesterol reduction, the HMG-CoA reductase inhibitors (statins) cannot be used during pregnancy. We present a case in which LDL apheresis via heparin-induced extracorporeal LDL precipitation was employed safely and efficaciously during pregnancy in a woman with heterozygous familial hypercholesterolemia and stable coronary artery disease.

Objective. —To explore the association of supplementary and dietary vitamin E and C intake with the progression of coronary artery disease. Design. —A subgroup analysis of the on-trial antioxidant vitamin intake database acquired in the Cholesterol Lowering Atherosclerosis Study, a randomized, placebo-controlled, serial angiographic clinical trial evaluating the risk and benefit of colestipol-niacin on coronary artery disease progression. Setting. —Community- and university-based cardiac catheterization laboratories. Subjects. —A total of 156 men aged 40 to 59 years with previous coronary artery bypass graft surgery. Intervention. —Supplementary and dietary vitamin E and C intake (nonrandomized) in association with cholesterol-lowering diet and either colestipol-niacin or placebo (randomized). Outcome. —Change per subject in the percentage of vessel diameter obstructed because of stenosis (%S) determined by quantitative coronary angiography after 2 years of randomized therapy on all lesions, mild/moderate lesions ( Results. —Overall, subjects with supplementary vitamin E intake of 100 IU per day or greater demonstrated less coronary artery lesion progression than did subjects with supplementary vitamin E intake less than 100 IU per day for all lesions (P=.04) and for mild/moderate lesions (P=.01). Within the drug group, benefit of supplementary vitamin E intake was found for all lesions (P=.02) and mild/moderate lesions (P=.01). Within the placebo group, benefit of supplementary vitamin E intake was not found. No benefit was found for use of supplementary vitamin C exclusively or in conjunction with supplementary vitamin E, use of multivitamins, or increased dietary intake of vitamin E or vitamin C. Conclusions. —These results indicate an association between supplementary vitamin E intake and angiographically demonstrated reduction in coronary artery lesion progression. Verification from carefully designed, randomized, serial arterial imaging end point trials is needed. (JAMA. 1995;273:1849-1854)

The Cholesterol Lowering Atherosclerosis Study (CLAS) was a randomized, placebo-controlled, angiographic trial testing combined colestipol-niacin therapy in 162 subjects. Two-year results (CLAS-I) showed decreased atherosclerosis progression and increased regression. We now describe a subgroup of 103 subjects treated for 4 years (CLAS-II). Changes in blood lipid, lipoproteincholesterol, and apolipoprotein levels were maintained, and at 4 years significantly more drug-treated subjects demonstrated nonprogression (52% drug- vs 15% placebo-treated) and regression (18% drug- vs 6% placebo-treated) in native coronary artery lesions. Significantly fewer drug-treated subjects developed new lesions in native coronary arteries (14% drug- vs 40% placebo-treated) and bypass grafts (16% drug- vs 38% placebo-treated). These results confirm CLAS-I findings and indicate that regression can continue for 4 years. They reaffirm the need for early initiation of vigorous long-term lipid lowering therapy in coronary bypass subjects. ( JAMA . 1990;264:3013-3017)

A serial blood-lipid-lowering study at the University of Southern California yielded unexpected findings on routine thyroid function monitoring. After 1 year of combined colestipol and niacin therapy, patients had reduced total serum thyroxine (T4) levels and increased triiodothyronine uptake ratios, an indicator of apparent decreases in thyroxine-binding globulin levels. Calculation of the free T4 index partially but not completely corrected for the apparent decrease in thyroxine-binding globulin, as determined by a relatively small decrease in the free T4 index compared with a large decrease in T4. Sequential sampling, using three separate methods, showed reduced thyroxine-binding globulin levels. The mechanism for these changes is unknown, but the fact that these patients were essentially euthyroid needs emphasis because the use of combined colestipol and niacin therapy is becoming more widespread.

The Cholesterol-Lowering Atherosclerosis Study (CLAS) was a randomized, placebo-controlled, angiographic trial testing combined colestipol hydrochloride and niacin therapy in 162 nonsmoking men aged 40 to 59 years with previous coronary bypass surgery. During two years of treatment there was a 26% reduction in total plasma cholesterol, a 43% reduction in low-density lipoprotein cholesterol, plus a simultaneous 37% elevation of high-density lipoprotein cholesterol. This resulted in a significant reduction in the average number of lesions per subject that progressed ( P P P P P P =.002). ( JAMA 1987;257:3233-3240)