PubMed Health⌕ Search

Biomedical subjects

X Q Zhao

Publications and source records attributed to X Q Zhao.

At least 19 recordsLinked to original sources
PubMed2000

Ca(2+)-dependent inhibition of actin-activated myosin ATPase activity by S100C (S100A11), a novel member of the S100 protein family.

S100C (S100A11, calgizzarin) inhibits the actin-activated myosin Mg(2+)-ATPase activity of smooth muscle in a dose-dependent manner: its half-maximal effect occurs at a S100C/actin molar ratio of 0.05 and its maximal effect occurs at a ratio of 0.20. Furthermore, S100C was found to bind to actin with a stoichiometry of 1:6-7 in the presence of Ca(2+), with an affinity of 1 x 10(-6) M determined by cosedimentation assays. Other Ca(2+)-binding proteins such as S100A1, S100A2, S100B, and calmodulin did not inhibit actin-activated myosin Mg(2+)-ATPase activity. Calmodulin, S100A1, and S100B reversed the inhibitory effect of calponin in a Ca(2+)-dependent manner, S100A2 had no effect, and S100C had additional inhibitory effects. The results suggest that S100C might be involved in the regulation of actin-activated myosin Mg(2+)-ATPase activity through its Ca(2+)-dependent interaction with actin filaments.

Actins↗
PubMed1999

Intracoronary thrombus and platelet glycoprotein IIb/IIIa receptor blockade with tirofiban in unstable angina or non-Q-wave myocardial infarction. Angiographic results from the PRISM-PLUS trial (Platelet receptor inhibition for ischemic syndrome management in patients limited by unstable signs and symptoms). PRISM-PLUS Investigators.

BACKGROUND: The present study describes the effects of tirofiban, a nonpeptide platelet glycoprotein (GP) IIb/IIIa receptor blocker, on the characteristics of culprit lesions in patients with unstable angina (UA) or non-Q-wave myocardial infarction (NQWMI). METHODS AND RESULTS: Of 1915 patients enrolled in PRISM-PLUS, 1491 had a readable film obtained a median of 65 hours after randomization. A core laboratory examined the culprit lesions for intracoronary thrombus burden (primary end point) and for TIMI flow grade distribution and severity of the obstruction and of underlying coronary artery disease (secondary end points). The combination of tirofiban plus heparin compared with heparin alone significantly reduced the intracoronary thrombus burden of the culprit lesions (OR=0.77, P=0.022), improved the perfusion grade (OR=0.65, P=0.002), and decreased the severity of the obstruction (P=0.037), but it did not influence the severity of the underlying plaque. Persistence of a thrombus in 45% of patients was associated with a 2.4-fold increase in the odds of death at 30 days (P=0.005) and a 2-fold increase in the odds of myocardial infarction (P=0.002). CONCLUSIONS: The addition of tirofiban to heparin reduced the thrombus burden of the culprit lesion and improved distal perfusion in patients with UA or NQWMI, which supports the clinical benefit observed with the combination treatment.

Aged↗
PubMed1998

Importance of endothelial function in mediating the benefits of lipid-lowering therapy.

Trials of lipid lowering by various methods have clearly demonstrated the benefits, clinically and angiographically. Evidence of slowed arterial disease progression and even regression has been convincing but modest, at best. For example, among those treated intensively in the Familial Atherosclerosis Treatment Study (FATS), the mean improvement in proximal stenosis severity was <1% per patient, and only 12% of all lesions showed convincing regression. Despite these modest arterial benefits, the associated reductions in major cardiovascular events have been surprisingly great (24-35% in 3 recent large trials and > or =50% in angiographic trials using combination therapies). The process of plaque disruption helps explain this discrepancy. Disruption can be predicted by a large accumulation of core lipid in the plaque and a high density of lipid-laden macrophages in its thinned fibrous cap. Lesions with these characteristics comprise only 10-20% of the overall lesion population but account for 60-90% of the acute clinical events. Lipid-lowering therapy has beneficial effects on these "high-risk" features of plaque morphology. The composite of data presented here supports the hypothesis that lipid-lowering therapy selectively depletes lipids from this relatively small but dangerous subgroup of fatty lesions, effectively stabilizing them.

Coronary Artery Disease↗
PubMed1998

Lipid altering or antioxidant vitamins for patients with coronary disease and very low HDL cholesterol? The HDL-Atherosclerosis Treatment Study Design.

Evidence supports the idea that substantial benefits may derive from treatments that increase high density lipoprotein (HDL) cholesterol (HDL-C), apolipoprotein (apo) A-I, HDL2 (or 2b) or the size of HDL particles with, or without, apo A-II. HDL3 appears to be neutral in terms of coronary artery disease risk, and apo A-II appears to be adverse. Because HDL particles serve as antioxidants in vitro, the hypothesis that low HDL-C reflects an antioxidant deficiency state appears tenable. Based on these observations, a three-year angiographic study was proposed and received funding. Enrollment began in January 1995 and was completed in January 1997.

Adult↗
PubMed1997

Moderate dose, three-drug therapy with niacin, lovastatin, and colestipol to reduce low-density lipoprotein cholesterol <100 mg/dl in patients with hyperlipidemia and coronary artery disease.

The efficacy, safety, and tolerability of a moderate dose, 3-drug lipid-lowering regimen were evaluated among 29 male patients with hyperlipidemia and coronary artery disease. In an initial 12-month phase, regular niacin, 500 mg qid, lovastatin, 20 mg bid, and colestipol, 10 g/bid, were given with dose adjustment for lipid targets and side effects. This was followed by 2 random sequence crossover phases (8 months each) alternating regular niacin with a polygel controlled-release formulation of niacin for use in this regimen. Lipid, lipoprotein, apoprotein, and clinical chemistry determinations were obtained at baseline, during the initial phase, at the 2 crossover phases, and at 6 weeks after therapy. A final questionnaire queried specific side effects and overall preferences. Low-/high-density lipoprotein (LDL/HDL) changed from means of 215/46 mg/dl at baseline, to 94/59 mg/dl after run-in, to 85/52 mg/dl after 8 months of controlled-release niacin, and to 98/56 mg/dl after 8 months of regular niacin (regular niacin vs controlled-release niacin, p <0.005/<0.05). The target of LDL < or = 100 mg/dl was achieved at 8 months by 83% of these patients with controlled-release niacin and by 52% with regular niacin (p <0.01). Compliance was 95% with controlled-release niacin versus 85% with regular niacin (p <0.001). The controlled-release niacin and regular niacin regimens did not differ in terms of uric acid, glucose, insulin, or asparate aminotransferase levels. Overall, 21% of patients called the 3 drugs "very easy" and 72% "fairly easy" to take. The controlled-release niacin-containing regimen was preferred by 21 patients and the regular niacin by 4. In conclusion, these regimens achieve striking lipid changes among hyperlipidemic patients. Controlled release is the preferred niacin preparation in terms of LDL reduction, compliance, patient preference, and achieving the National Cholesterol Education Program guideline of LDL < or = 100 mg/dl. The 2 niacin preparations did not differ in evidence of toxicity.

Cholesterol, LDL↗
PubMed1997

Influence of environmental temperature on in vivo energy expenditure in vitro ouabain-sensitive respiration in duodenal mucosa and liver in rats fed different levels of dietary fiber or protein.

Seventy two Wistar rats were used in two repeat studies to investigate the effect of environmental temperature (18 degrees C or 28 degrees C) and increasing levels of dietary fibre (low, 68 g/kg DM; medium 110 g/kg DM; high, 157 g/kg DM) or protein (low, 91 g/kg DM; medium, 171 g/kg DM; high, 262 g/kg DM) on digestive tract, visceral organ size, energy metabolism, and respiration attributable to Na+,K(+)-ATPase activity in duodenal mucosa and liver. Total and ouabain-sensitive (a measure of Na+,K(+)-ATPase activity) O2 consumption in vitro of tissues were measured polarographically using a Clark-style YSI biological O2 monitor. Whole body heat production (in vivo) was measured using open-circuit respiration chambers. The weight of the visceral organs was higher in rats housed at 18 degrees C than at 28 degrees C. The empty weight of the small intestine, caecum, and colon increased as the level of dietary fibre increased (P 0.05). Heat production as a proportion of metabolizable energy was higher (P < 0.05) at 18 degrees C than at 28 degrees C in the first experiment but this difference was significant in the second experiment. Rats fed the low protein diet had significantly higher (P > 0.05) heat production than those fed medium or high protein diets. Compared to 28 degrees C, environmental temperature of 18 degrees C caused an increased total and ouabain-sensitive O2 consumption in duodenal mucosa. There was no significant effect of environmental temperature on total and ouabain-sensitive O2 consumption in the liver. However, ouabain-sensitive O2 consumption in liver was significantly higher (P 0.05) when rats were fed a low protein diet compared to the medium or high protein diet. Total and ouabain-sensitive O2 consumption increased in duodenal mucosa of rats fed low level of dietary fibre compared to the medium or high dietary fibre diets. The in vitro results corresponded with the whole animal energy expenditure and O2 consumption in vivo.

Animals↗
PubMed1997

Energy expenditure and quantitative oxidation of nutrients in rats (Rattus norvegicus) kept in different thermal environments and given two levels of dietary fiber.

A study was performed to investigate the effect of environmental temperature (16 degrees C, 24 degrees C or 32 degrees C) and dietary fiber (DF) on energy expenditure and quantitative oxidation of nutrients in rats. Forty-eight male rats, initial body weight 90-105 g, were allocated to eight groups in two series. The rats kept at 24 degrees C was repeated in both series. Low and high fiber diets (56 vs. 257 g DF/kg dry matter) were studied in 6-week balance experiments. The rats in all groups were offered the same amount of air-dried food. Indirect calorimetry was used to measure the energy metabolism. The difference in heat production (HP) calculated by RQ and CN methods was < 2% and was not affected by environmental temperature and DF. The relation between fat and protein oxidation changed from 1.54 to 1.00 when the ambient temperature changed from 16 degrees C to 32 degrees C. The contribution of carbohydrate oxidation to total HP was lowest at 16 degrees C, whereas the fat and protein oxidation was highest at 16 degrees C. The oxidation of nutrients was not influenced by DF. The additional energy retained at the higher temperatures had a constant ratio between fat and protein, i.e., 70:30. At an energy retention of 65.8 kJ/kg0.75 d or less, body fat is mobilized and only protein deposited. Because of higher HP, rats living in the cold environment used more fat as substrate for HP than rats kept in warmer environments. The cold environment results in an increase in the amount of interscapular brown adipose tissue, but no significant difference was found between DF levels.

Adipose Tissue, Brown↗
PubMed1997

Secondary prevention of heart disease amongst patients with lipid abnormalities: practice and trends in the United States.

Patients with established coronary disease and abnormalities of lipid metabolism represent a particularly important subgroup, since their mortality risk is typically 10 times greater than that amongst-subjects with comparable risk factors but no clinical history. Such patients are commonly treated initially with anti-anginal therapy; if ischaemic symptoms persist they often undergo revascularization (bypass or angioplasty). While invasive procedures restore blood flow and relieve ischemia, they do not, in most cases, reduce risk of subsequent MI or death, or alter the underlying atherogenic process(es). Despite this, there has been a progressive 54% decline in age-adjusted cardiac mortality over the period 1960-1995, which appears best attributable to US lifestyle changes. In particular, the past decade has provided compelling evidence for the merits of a fourth approach: comprehensive risk factor management. Clinical outcome studies have confirmed the substantial merit of aspirin prophyllaxis and of intensive lipid-lowering therapy in secondary prevention. Prospective angiographic trials and evidence from studies of vascular biology have provided insight into mechanisms of benefit. As a consequence, lipid therapy and aspirin use have increased greatly among middle aged and older US citizens, especially those with CAD. The growth of comprehensive medical management now rivals that of invasive revascularization in secondary prevention.

Aspirin↗
PubMed1997

The energy value of short-chain fatty acids infused into the caecum of pigs.

The present work was undertaken to study the energy value of a mixture of acetic, propionic and butyric acids (0.682:0.226:0.092) infused intracaecally in growing pigs. A basal diet low in fibre (42 g NSP/kg DM) was given at below the requirement for maximum weight gain. In six 2-week periods, N and energy balance measurements in eight growing pigs were carried out with and without infusion of short-chain fatty acids (SCFA). Heat production was measured using open-circuit chambers and the concentration of SCFA in faeces was determined. Less than 1% of the infused SCFA was excreted in faeces illustrating the capacity of the hind-gut to absorb and metabolize SCFA. Infusion of SCFA did not affect the digestibility of nutrients and energy. However, N retention increased demonstrating that SCFA are an energy source for protein gain when pigs are fed at below the requirement of energy. Increased CH4 production together with an increased excretion of branched-chain fatty acids in faeces suggested that there was a higher microbial activity in the hind-gut during infusion. The partial utilization of the infused energy in SCFA was 0.821. A small proportion of the infused energy in SCFA was retained in protein (0.099) and a considerable amount was retained as fat (0.722).

Animals↗
PubMed1996

Effectiveness of revascularization in the Emory angioplasty versus surgery trial. A randomized comparison of coronary angioplasty with bypass surgery.

BACKGROUND: The Emory Angioplasty Versus Surgery Trial (EAST) was designed to determine whether percutaneous transluminal coronary angioplasty (PTCA) is as effective as coronary artery bypass graft surgery (CABG) in restoring arterial perfusion capacity in eligible patients with multivessel disease. METHODS AND RESULTS: Of 392 patients in EAST, 198 were randomized to PTCA and 194 to CABG. Index lesions (2.7 +/- 1.0 per patient) were those with > or = 50% stenosis judged treatable by both angioplasty and surgery. Coronary segments jeopardized by these index lesions were designated as index segments (4.4 +/- 1.4 per patient). Percent stenosis was measured by quantitative angiography at the point of greatest obstruction in the main perfusion path of each index segment. The EAST primary arteriographic end point was the percent of a patient's index segments with < 50% stenosis in the main perfusion pathways at 1 and 3 years. At baseline, the percent of index segments for which revascularization was attempted was 85% for PTCA and 98% for CABG (P < .0001). At 1 year, PTCA patients had a smaller percentage of successfully revascularized index segments than CABG patients (59% versus 88%, P < .001). At 3 years, the findings were similar but less striking (70% versus 87%, P < .001). When only "high-priority" index segments (2.1 +/- 1.6 per patient) were considered, baseline attempts were comparable (96% versus 99%, P = NS); despite this, CABG remained more successful at 1 (64% versus 93%, P < .001) and 3 (76% versus 89%, P < .01) years. However, the mean percent of index segments free of severe stenosis (> or = 70%) did not differ between PTCA and CABG patients at 3 years (93% versus 95%, P = NS). Furthermore, the frequency of patients with all index segments free of severe stenosis did not differ between the two groups at 1 (76% versus 83%, P = NS) or 3 (82% for both PTCA and CABG) years. CONCLUSIONS: In patients with multivessel disease, index segment revascularization was more complete with CABG than PTCA at both 1 and 3 years. However, when the physiological priority of the target lesion and the measured severity of the residual stenosis are taken into account, the advantage of CABG becomes less significant or nonsignificant. This may, in part, explain why these two strategies did not differ in terms of the EAST primary clinical end points over 3 years.

Aged↗
PubMed1996

The influence of dietary fibre and environmental temperature on the development of the gastrointestinal tract, digestibility, degree of fermentation in the hind-gut and energy metabolism in pigs.

The present study was undertaken to provide detailed information about the effect of dietary fibre (DF) level on the development of the digestive tract, on nutrient digestibility and on energy and protein metabolism of pigs housed in low (13 degrees) or high (23 degrees) thermal environments. Low- and high-fibre diets (59 v. 268 g DF/kg DM) were studied in three balance periods with fistulated pigs in the weight range 45-120 kg. Heat production was measured using open-circuit respiration chambers. Pea fibre and pectin were used to adjust the DF level in the high-fibre diet. Per kg empty body weight the stomach, caecum and colon and the length of colon were significantly greater in pigs consuming the high-fibre diet than in those on the low-fibre diet. Pigs kept at low temperature had significantly heavier caecums than those kept at the high temperature. Digestibilities of protein, DM and energy were lowest for the high-fibre diet. Only minor amounts of NSP and its constituent sugars were degraded anterior to the ileum, whereas in the hind-gut the fermentation of the total NSP fraction was high, being 0.77 for the high-fibre diet and 0.59 for the low-fibre diet. Feeding the high-fibre diet increased the flow of digesta through the terminal ileum 5-6-fold and an extra 460 g organic matter was fermented daily in the hind-gut compared with pigs fed on the low-fibre diet. The amount of retained energy as a proportion of metabolizable energy decreased in relation to the amount of energy fermented in the hind-gut. Based on the present data it was estimated that the relative value of energy derived from hind-gut fermentation was 0.73 in comparison with energy enzymically digested in the small intestine. There was negligible effect of the temperature--fibre interaction on energy metabolism. However, it could be calculated that the decrease in temperature from 23 degrees to 13 degrees was associated with an increase in heat production by 2.9 MJ/pig per d.

Animals↗
PubMed1996

The influence of dietary fibre source and level on the development of the gastrointestinal tract, digestibility and energy metabolism in broiler chickens.

The present study was undertaken to provide detailed information about the effect of fibre source (pea fibre, wheat bran or oat bran) at inclusion levels of 0, 187 and 375 g/kg diet on the development of the digestive tract, nutrient digestibility and energy and protein metabolism in broiler chickens. Heat production was measured using open-air-circuit respiration chambers. Diets with increasing levels of pea fibre decreased the DM in droppings and increased excreta output (2.5-fold) relative to DM intake. Adaptation to increased dietary fibre levels included increases in the size of the digestive system, with pea fibre exerting a stronger impact than wheat bran or oat bran. The length of the intestine, and particularly the length and weight of the caecum, increased with the fibre level. The digestibility of all nutrients also decreased with increasing fibre level. The decrease in the digestibility in relation to NSP for the three fibre sources was bigger for oat bran (0.0020 per g dietary NSP) than for pea fibre and wheat bran (0.0014 and 0.0016 per g dietary NSP) indicating that the cell walls in oat bran (aleurone and subaleurone) had a significant negative effect on the digestibility of cellular nutrients, i.e. protein and fat. The degradation of the NSP constituents was far lower in chickens than found in other animal species such as pigs and rats, thus supporting the view that chickens do not ferment fibre polymers to a great extent. Excretion of organic acids (mainly lactic acid and acetic acid) accounted for up to 2% of metabolizable energy (ME) intake with the highest excretion for the high-fibre diets. H2 excretion was related to the amount of NSP degraded and indicated higher microbial fermentation with increasing fibre levels. The chickens' feed intake responded to a great extent to dietary ME concentration but expressed in terms of metabolic body size (W0.75) ME intake was depressed at the high fibre levels. Dietary NSP was able to explain between 86% (oat bran) and 96% (pea fibre) of the variation in ME concentration. The amount of energy available from fermentation of NSP appears to reach a maximum of 42 kJ/d independent of fibre source and level. Expressed in relation to ME intake the NSP fermentation contributed 3-4%. With increasing fibre intake the partitioning of retained energy between body protein and body fat changed in favour of protein.

Animals↗
PubMed1996

Energy metabolism and protein balance in growing rats housed in 18 degree C or 28 degree C environments and fed different levels of dietary protein.

A study was performed to investigate the effect of environmental temperature and increasing levels of protein in the diet on visceral organ size, digestibility, protein balance and energy metabolism in rats. Thirty-six male Wistar rats, initial body weight 77-80 g, were used in a factorial design consisting of three levels of dietary protein and two environmental temperatures of either 18 or 28 degrees C. Three fish meal-based diets were prepared to contain 91, 171 and 262 g protein (N X 6.25/kg diet). Gas-exchange measurements were made and urine and feces were quantitatively collected. The weights of the visceral organs from rats housed at 18 degrees C were greater (P < 0.05) than those of rats housed at 28 degrees C. The digestibilities of dry matter and protein were not affected by environmental temperature, whereas fat and energy digestibilities were higher (P < 0.05) at 18 degrees C than at 28 degrees C. As the level of protein was increased, the digestibilities of protein, energy and fat increased (P < 0.05). Protein intake and protein retention were higher at 18 degrees C (P < 0.05) than at 28 degrees C and increased (P < 0.05) as dietary protein concentration increased. Apparent biological value was lower (P < 0.05) at 18 degrees C than at 28 degrees C and decreased (P < 0.05) as dietary protein level increased. Heat production as a percentage of metabolizable energy was higher (P < 0.05) for the low protein diet than for the medium and high protein diets. The efficiency of energy utilization was depressed (P < 0.05) for the high protein diet when rats were kept at 28 degrees C. The results suggest that thermogenesis was induced when low protein was fed. The increase in thermogenesis may have been important in regulating energy balance and maintaining a constant body temperature in a cold environment.

Animals↗
PubMed1995

Effects of lowering elevated LDL cholesterol on the cardiovascular risk of lipoprotein(a).

OBJECTIVE: To determine if lowering elevated low-density lipoprotein cholesterol (LDL-C) levels offsets the adverse effect of raised lipoprotein(a) (Lp[a]) levels on coronary artery disease (CAC) in men. DESIGN: Randomized, double-blind, placebo-controlled trial of lipid lowering for CAD. SETTING: Post hoc analysis of the Familial Atherosclerosis Treatment Study. PARTICIPANTS: A total of 146 men aged 62 years or younger with CAD and apolipoprotein B levels of at least 125 mg/dL. INTERVENTION: Patients received a Step II Diet and lovastatin (40 mg daily) plus colestipol (30 g daily), niacin (4 g daily) plus colestipol, or placebo (plus colestipol if LDL-C > 90th percentile) for 2.5 years. They were grouped by their LDL-C responses: "minimal" if LDL-C decreased by 10% or less from baseline (mean [SD] change, +6% [13%]) and "substantial" if LDL-C decreased more than 10% (mean [SD] change, -40% [16%]). MAIN OUTCOME MEASURE: Impact of lowering elevated LDL-C on the cardiac event rate (death, myocardial infarction, and revascularization for refractory ischemia) and CAD change associated with elevated Lp(a). RESULTS: In multivariate analyses, the best correlate of baseline CAD severity was Lp(a) (r = 0.30; P < .001). For 36 patients with minimal LDL-C reduction, CAD progression correlated only with in-treatment Lp(a) levels (r = 0.45; P < .01), but for 84 patients with substantial LDL-C reduction, disease regressed and its change correlated with in-treatment LDL-C (r = 0.24; P < .05) but not with Lp(a) (r = -0.05). Lipoprotein(a) levels were not significantly altered in either group. For 40 patients with Lp(a) at the 90th percentile or higher, events were frequent (39%) if reduction of LDL-C was minimal, but were few (9%) if reduction was substantial (relative risk, 0.23; 95% confidence interval, 0.06 to 0.99). CONCLUSIONS: In men with CAD and elevated LDL-C, Lp(a) levels were dominant correlates of baseline disease severity, its progression, and event rate over 2.5 years. However, with substantial LDL-C reductions, persistent elevations of Lp(a) were no longer atherogenic or clinically threatening. This provides a possible direction for treatment in such patients with elevated Lp(a) and LDL-C.

Adult↗
PubMed1995

What benefit can be derived from treating normocholesterolemic patients with coronary artery disease?

Controversy still remains regarding the possible clinical or arteriographic benefit of intensive lipid-altering therapy in patients who have coronary artery disease and apparently normal lipid levels. Resolution of this controversy appears to depend on an improved understanding of the role of variables other than total or low density lipoprotein cholesterol levels. A comparison of the "normolipidemic" subgroup of The Familial Atherosclerosis Treatment Study patients and The Harvard Atherosclerosis Reversibility Project patients indicates that low levels of high density lipoprotein cholesterol and elevated levels of apolipoprotein B appear to increase considerably the likelihood of benefit from intensive lipid-altering therapy. Other risk-related variables such as systolic blood pressure and lipoprotein(a) further contribute to the prediction of risk and possibly to the potential for treatment benefit.

Adult↗
PubMed1994

A randomized trial comparing coronary angioplasty with coronary bypass surgery. Emory Angioplasty versus Surgery Trial (EAST)

BACKGROUND: The clinical benefit of percutaneous transluminal coronary angioplasty (PTCA) as compared with coronary-artery bypass grafting (CABG) for patients with multivessel coronary artery disease has not been established. To determine the outcomes of these treatments in patients referred for the first time for coronary revascularization, we conducted a three-year prospective, randomized trial comparing the two procedures. METHODS: Revascularization was performed by accepted methods. Follow-up clinical information was collected every six months, and coronary arteriography and thallium stress scanning were performed at one and three years. The primary end point was a composite of death, Q-wave myocardial infarction, and a large ischemic defect identified on thallium scanning at three years. Secondary end points included clinical and angiographic status and the need for additional revascularization procedures. Data were analyzed according to the intention-to-treat principle. RESULTS: Of the 5118 patients screened for the trial, 842 (16.5 percent) were eligible for enrollment, and 392 (7.7 percent) agreed to participate. A total of 194 patients were randomly assigned to the CABG group, and 198 to the PTCA group. The primary end point occurred in 27.3 percent of the CABG group and 28.8 percent of the PTCA group (P = 0.81). Death occurred in 6.2 percent of the CABG group and 7.1 percent of the PTCA group (P = 0.73 by log-rank test). At three years, the proportions of patients in the CABG group who required repeated bypass surgery (1 percent) or angioplasty (13 percent) were significantly lower than the proportions in the PTCA group (22 and 41 percent, respectively; P < 0.001). Angiographic studies at three years showed a greater degree of revascularization in the CABG group. Angina was more frequent in the PTCA group (20 percent) than in the CABG group (12 percent). CONCLUSIONS: We found that CABG and PTCA did not differ significantly with respect to the occurrence of the composite primary end point. Consequently, the selection of one procedure over the other should be guided by patients' preferences regarding the quality of life and the possible need for subsequent procedures.

Angioplasty, Balloon, Coronary↗