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Background: Poor preoperative health-related quality of life (HRQoL) has been associated with reduced short-term survival after coronary artery bypass graft (CABG) surgery; however, its impact on long-term mortality is unknown. This study's objective was to determine if baseline HRQoL status predicts 5-year post-CABG mortality., Methods: This prespecified, randomized on/off bypass follow-up study (ROOBY-FS) subanalysis compared baseline patient characteristics and HRQoL scores, obtained from the Seattle Angina Questionnaire (SAQ) and Veterans RAND Short Form-36 (VR-36), between 5-year post-CABG survivors and nonsurvivors. Standardized subscores were calculated for each questionnaire. Multivariable logistic regression assessed whether HRQoL survey subcomponents independently predicted 5-year mortality (p ≤ .05)., Results: Of the 2203 ROOBY-FS enrollees, 2104 (95.5%) completed baseline surveys. Significant differences between 5-year post-CABG deaths (n = 286) and survivors (n = 1818) included age, history of chronic obstructive pulmonary disease, stroke, peripheral vascular disease, renal dysfunction, diabetes, lower left ventricular ejection fraction, atrial fibrillation, depression, non-White race/ethnicity, lower education status, and off-pump CABG. Adjusting for these factors, baseline VR-36 physical component summary score (p = .01), VR-36 mental component summary score (p < .001), and SAQ physical limitation score (p = .003) were all associated with 5-year all-cause mortality., Conclusions: Pre-CABG HRQoL scores may provide clinically relevant prognostic information beyond traditional risk models and prove useful for patient-provider shared decision-making and enhancing pre-CABG informed consent., (Published 2022. This article is a U.S. Government work and is in the public domain in the USA.)

Background: Observational studies have documented an off-pump over on-pump advantage for high-risk patients, including diabetic patients. Randomized trials have not confirmed this advantage. The VA Randomization On Versus Off Bypass (ROOBY) trial randomly assigned 2,203 coronary artery bypass graft surgery (CABG) patients at 18 sites to either on-pump (n=1,099) or off-pump (n=1,104) procedures. An a priori ROOBY aim was to evaluate treatment impact on diabetic patients., Methods: Actively treated diabetic patients (n=835, receiving oral hypoglycemic or insulin medications) received off-pump CABG (n=402) or on-pump CABG (n=433). The primary ROOBY trial endpoints were a short-term composite (30-day operative death or major complications) and a 1-year composite (death, nonfatal acute myocardial infarction, or repeat revascularization). Secondary ROOBY endpoints included 1-year all-cause death, 1-year graft patency, 1-year changes from baseline in neurocognitive status and health-related quality of life, and costs., Results: Diabetic patients' risk factors at baseline were balanced across treatments. For diabetic patients, the primary short-term composite outcome rate showed a worse trend for off-pump (8.0%) than on-pump (3.9%, p=0.013), with no difference in the 1-year primary composite outcome or 1-year death rate. One-year patency was 83.1% off-pump versus 88.4% on-pump (p=0.004). No differences were found in neurocognitive, health-related quality of life, discharge cost, and 1-year cumulative cost., Conclusions: Concordant with the ROOBY trial's overall findings, off-pump CABG yielded no advantage over on-pump CABG for actively treated diabetic patients. The 1-year graft patency was lower and the short-term composite trended higher for off-pump CABG, with no other significant outcome or cost differences., (Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objectives: This study sought to evaluate the short- and long-term outcomes for smokers with non-ST-segment elevation acute coronary syndromes (NSTE-ACS)., Background: Smoking has been associated with the "paradox" of reduced mortality after acute myocardial infarction (MI). This is thought to be due to favorable baseline characteristics and less diffuse coronary artery disease (CAD) among smokers., Methods: In the ACUITY (Acute Catheterization and Urgent Intervention Triage Strategy) trial, 13,819 patients (29.1% smokers) with moderate- to high-risk NSTE-ACS underwent angiography and, if indicated, revascularization., Results: Smokers were significantly younger and had fewer comorbidities than nonsmokers. Incidence of death and MI were comparable at 30 days, although smokers had significantly reduced risks of 30-day major bleeding (hazard ratio [HR]: 0.80, 95% confidence interval [CI]: 0.67 to 0.96; p = 0.016) and 1-year mortality (HR: 0.797, 95% CI: 0.65 to 0.97; p = 0.027). After correction for baseline and clinical differences, smoking was no longer predictive of major bleeding (odds ratio: 1.06, 95% CI: 0.86 to 1.32; p = 0.56) and was associated with higher 1-year mortality (HR: 1.37, 95% CI: 1.07 to 1.7; p = 0.013). This pattern of reversed risk after multivariable correction held true for those smokers requiring percutaneous coronary intervention. Core laboratory angiographic analysis showed that smokers and nonsmokers were comparable in terms of the extent of CAD, Thrombolysis In Myocardial Infarction flow, myocardial blush, and the presence of thrombi., Conclusions: In contrast to the paradox previously described in ST-segment elevation MI, our analysis finds smoking to be an independent predictor of higher 1-year mortality in patients presenting with NSTE-ACS, and our angiographic study demonstrates CAD in smokers that is comparable to that in nonsmokers but evident ∼1 decade earlier. (Acute Catheterization and Urgent Intervention Triage Strategy [ACUITY]; NCT00093158)., (Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: Aged garlic extract with supplement (AGE-S) significantly reduces coronary artery calcium (CAC). We evaluated the effects of AGE-S on change in white (wEAT) and brown (bEAT) epicardial adipose tissue, homocysteine and CAC., Methods: Sixty subjects, randomized to a daily capsule of placebo vs. AGE-S inclusive of aged garlic-extract (250 mg) plus vitamin-B12 (100 μg), folic-acid (300 μg), vitamin-B6 (12.5mg) and L-arginine (100mg) underwent CAC, wEAT and bEAT measurements at baseline and 12 months. The postcuff deflation temperature-rebound index of vascular function was assessed using a reactive-hyperemia procedure. Vascular dysfunction was defined according to the tertiles of temperature-rebound at 1 year of follow-up. CAC progression was defined as an annual-increase in CAC>15%., Results: From baseline to 12 months, there was a strong correlation between increase in wEAT and CAC (r(2)=0.54, p=0.0001). At 1 year, the risks of CAC progression and increased wEAT and homocysteine were significantly lower in AGE-S to placebo (p<0.05). Similarly, bEAT and temperature-rebound were significantly higher in AGE-S as compared to placebo (p<0.05). Strong association between increase in temperature-rebound and bEAT/wEAT ratio (r(2)=0.80, p=0.001) was noted, which was more robust in AGE-S. Maximum beneficial effect of AGE-S was noted with increase in bEAT/wEAT ratio, temperature-rebound, and lack of progression of homocysteine and CAC., Conclusions: AGE-S is associated with increase in bEAT/wEAT ratio, reduction of homocysteine and lack of progression of CAC. Increases in bEAT/wEAT ratio correlated strongly with increases in vascular function measured by temperature-rebound and predicted a lack of CAC progression and plaque stabilization in response to AGE-S., (Published by Elsevier Ireland Ltd.)

Background: Patients with chronic obstructive pulmonary disease (COPD) are at inherent risk for higher rates of adverse events after coronary artery bypass graft surgery (CABG). As compared with on-pump CABG (ONCAB), it has been suggested that beating heart or off-pump CABG (OPCAB) may differentially benefit high-risk COPD patients., Methods: Intraoperative, 30-day and 1-year outcomes were compared for COPD patients randomized to OPCAB (n = 220) versus ONCAB (n = 238) within the Veterans Affairs' Randomized On/Off Bypass (ROOBY) trial. As COPD patients may more likely incur adverse post-CABG outcomes, a propensity analysis was performed comparing all ROOBY patients with COPD (n = 458) versus those without COPD (n = 1,745)., Results: For COPD patients, the baseline characteristics were similar between the 2 revascularization approaches. In these patients, the intraoperative complication rate was higher with OPCAB than ONCAB (21.9% vs 10.1%, respectively; p < 0.001), but there were no significant differences in the 30-day (7.3% vs 7.6%, p = 1.00) or 1-year composite outcome rates (9.5% vs 7.1%, p = 0.39) between the groups. Comparing the COPD patients with propensity-matched non-COPD patients, there was no difference in 1-year major adverse cardiovascular events (including the 1-year composite major adverse cardiac events (MACE) outcome, as well as the individual MACE outcomes for all cause death, acute myocardial infarction, or repeat revascularization)., Conclusions: In COPD patients, there were more intraoperative complications and no differences in 30-day or 1-year outcomes with OPCAB as compared with ONCAB. Similar to patients without COPD, there was no benefit to using an OPCAB approach in COPD patients., (Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: The need of having feasible screening tools like Coronary Calcium Scoring (CCS) and CT Coronary Artery (CTCA) for Coronary Artery Disease (CAD) has become paramount. We aimed to evaluate the accuracy of CCS in determining the degree of stenosis of coronary vessels as compared to that determined by CTCA in a South Asian population., Methods: A retrospective study was conducted at The Aga Khan University Hospital. A total of 539 patient records were reviewed who had undergone CCS and CTCA between 2008 and 2010. Patient records were reviewed by comparing their CCS and CTCA results., Results: About 268 out of 301 (89%) patients with a CCS of 0-9 were found to be free of stenosis on CTCA. On a CCS of 10-99, 110 out of 121 (91%) patients were either free of stenosis or had mild stenosis. About 66 out of 79 (84%) patients had moderate or severe stenosis with a calcium score of 100-400 while none of the patients were free of stenosis. Around 28 out of 38 (74%) patients with a CCS of more than 400 had severe stenosis. However, only 04 patients (11%) were found to have mild stenosis. Spearman's rho revealed a correlation coefficient of 0.791 with a p-value of <0.001., Conclusion: Our study reaffirms that in South Asian population, low CCS (<100) is associated with no or minimal stenosis while high CCS warrants further investigation; hence, making it a reliable tool for screening patients with CAD.

Post-traumatic stress disorder (PTSD) is associated with increased risk of multiple medical problems including myocardial infarction. However, a direct link between PTSD and atherosclerotic coronary artery disease (CAD) has not been made. Coronary artery calcium (CAC) score is an excellent method to detect atherosclerosis. This study investigated the association of PTSD to atherosclerotic CAD and mortality. Six hundred thirty-seven veterans without known CAD (61 ± 9 years of age, 12.2% women) underwent CAC scanning for clinical indications and their psychological health status (PTSD vs non-PTSD) was evaluated. In subjects with PTSD, CAC was more prevalent than in the non-PTSD cohort (76.1% vs 59%, p = 0.001) and their CAC scores were significantly higher in each Framingham risk score category compared to the non-PTSD group. Multivariable generalized linear regression analysis identified PTSD as an independent predictor of presence and extent of atherosclerotic CAD (p <0.01). During a mean follow-up of 42 months, the death rate was higher in the PTSD compared to the non-PTSD group (15, 17.1%, vs 57, 10.4%, p = 0.003). Multivariable survival regression analyses revealed a significant linkage between PTSD and mortality and between CAC and mortality. After adjustment for risk factors, relative risk (RR) of death was 1.48 (95% confidence interval [CI] 1.03 to 2.91, p = 0.01) in subjects with PTSD and CAC score >0 compared to subjects without PTSD and CAC score equal to 0. With a CAC score equal to 0, risk of death was not different between subjects with and without PTSD (RR 1.04, 95% CI 0.67 to 6.82, p = 0.4). Risk of death in each CAC category was higher in subjects with PTSD compared to matched subjects without PTSD (RRs 1.23 for CAC scores 1 to 100, 1.51 for CAC scores 101 to 400, and 1.81 for CAC scores ≥400, p <0.05 for all comparisons). In conclusion, PTSD is associated with presence and severity of coronary atherosclerosis and predicts mortality independent of age, gender, and conventional risk factors., (Published by Elsevier Inc.)

A risk-management approach based on the Framingham risk score (FRS), although useful in preventing future coronary artery disease (CAD) events, is unable to identify a considerable portion of patients with CAD who need aggressive medical management. Coronary artery calcium (CAC), an anatomic marker of atherosclerosis, correlates well with presence and extent of CAD. This study investigated mortality risk associated with CAC score and FRS in subjects classified as "low risk" versus "high risk" based on FRS. In total 730 veterans without known CAD (61 ± 10 years old, 12.8% women) underwent measurement of their FRS and CAC. Subjects were classified as "discordant low risk" (DLR) if their FRS was <10% and CAC score was ≥ 100 (n = 108, 14.8%) or "discordant high risk" (DHR) if their FRS was ≥ 20% and CAC score was 0 (n = 104, 14.2%). Survival analysis was used to compare mortality rates associated with FRS and CAC in DLR versus DHR subjects. Mortality rate during the mean 48-month follow-up was 7.3% (n = 53) including 18.5% (n = 20) in the DLR group and 7.7% (n = 8) in the DHR group, respectively. Adjusted relative risks of mortality were 5.46 (95% confidence interval [CI] 2.44 to 12.20, p = 0.0001) in subjects with CAC score ≥ 100 compared to CAC score 0 and 1.35 (95% CI 1.01 to 4.32, p = 0.04) in subjects with FRS ≥ 20% compared to FRS <10%. Adjusted relative risk of mortality was 3.6 (95% CI 1.57 to 8.34, p = 0.003) for DLR compared to DHR. Areas under the receiver operator curve to predict mortality were 0.72 for FRS, 0.82 for CAC score, and 0.92 for the combination. In conclusion, the prognostic value of CAC to predict future mortality is superior to the FRS. Addition of CAC score to FRS significantly improves the identification and prognostication of patients without known CAD., (Published by Elsevier Inc.)

Objective: Ventricular dysfunction in asymptomatic patients is directly linked to the eventual development of symptomatic congestive heart failure. This study investigates whether subclinical left ventricular (LV) and right ventricular (RV) dysfunctions measured by computed tomography angiography is associated with the severity of coronary artery disease (CAD)., Methods and Results: We studied 1608 consecutive patients with suspected CAD (age 62 ± 10 years, 64% male), who underwent coronary artery calcium (CAC) scanning and computed tomography angiography. RV and LV volumes at end systole and end diastole were measured, and stroke volume and ejection fraction were calculated using the Simpson method and piecewise smooth subdivision surface (PSSS) method. Analysis by Simpson was performed on short axis and apical four-chamber views. Axial images were used to measure RV and LV volumes by the PSSS method. CAD was defined as normal, nonobstructive, and obstructive (0% stenosis, luminal stenosis 1-49 and 50%+, respectively). There was a strong agreement between PSSS and Simpson method RV ejection fraction (RVEF) and LV ejection fraction (LVEF) measurement. RVEF and LVEF decreased proportionally from CAC 0 to CAC 100+, also from normal-to-diseased coronaries (P=0.001). After adjustment for cardiovascular risk factors, the mean LVEF and RVEF decreased 2.8 and 2.4%, respectively in CAC 100+ compared with CAC 0. Similarly, LVEF and RVEF decreased significantly in nonobstructive CAD (-3.5 and -3.1%, respectively) and obstructive CAD (-5.9 and -4.5%, respectively) compared with normal coronaries, respectively (P<0.05). The relative risk of each 5% decrease in LVEF and RVEF was 1.33 and 1.29 for nonobstructive CAD and 1.54 and 1.33 for obstructive CAD, respectively., Conclusion: The presence and severity of coronary atherosclerosis is significantly associated with subclinical RV and LV dysfunctions.

It was previously reported that event-free survival rates of symptomatic patients with coronary artery disease (CAD) diagnosed by computed tomographic angiography decreased incrementally from normal coronary arteries to obstructive CAD. The aim of this study was to investigate the clinical outcomes of symptomatic patients with nonobstructive CAD with luminal stenoses of 1% to 49% on the basis of coronary plaque morphology in an outpatient setting. Among 3,499 consecutive symptomatic subjects who underwent computed tomographic angiography, 1,102 subjects with nonobstructive CAD (mean age 59 ± 14 years, 69.9% men) were prospectively followed for a mean of 78 ± 12 months. Coronary plaques were defined as noncalcified, mixed, and calcified per patient. Multivariate Cox proportional-hazards models were developed to predict all-cause mortality. The death rate of patients with nonobstructive CAD was 3.1% (34 deaths). The death rate increased incrementally from calcified plaque (1.4%) to mixed plaque (3.3%) to noncalcified plaque (9.6%), as well as from single- to triple-vessel disease (p <0.001). In subjects with mixed or calcified plaques, the death rate increased with the severity of coronary artery calcium from 1 to 9 to ≥ 400. The risk-adjusted hazard ratios of all-cause mortality in patients with nonobstructive CAD were 3.2 (95% confidence interval 1.3 to 8.0, p = 0.001) for mixed plaques and 7.4 (95% confidence interval 2.7 to 20.1, p = 0.0001) for noncalcified plaques compared with calcified plaques. The areas under the receiver-operating characteristic curve to predict all-cause mortality were 0.75 for mixed and 0.86 for noncalcified coronary lesions. In conclusion, this study demonstrates that the presence of noncalcified and mixed coronary plaques provided incremental value in predicting all-cause mortality in symptomatic subjects with nonobstructive CAD independent of age, gender, and conventional risk factors., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Rationale and Objectives: Epicardial adipose tissue (EAT), pericardial adipose tissue (PAT), and subcutaneous adipose tissue (SAT) are mediators of metabolic risk and may be involved in the pathogenesis of coronary artery disease. The aim of this study was to investigate the association of visceral and subcutaneous fat depots with the presence and severity of coronary artery calcium (CAC) in asymptomatic individuals., Materials and Methods: One hundred eleven consecutive subjects underwent CAC assessment, and their Framingham risk scores were measured. EAT, total thoracic adipose tissue, and SAT volumes were measured from slice level 15 mm above to 30 mm below the ostium of the left main coronary artery. PAT was calculated as thoracic adipose tissue - EAT. SAT was defined as the volume of fat depot anterior to the sternum and posterior to the vertebra. CAC was defined as 0, 1 to 100, 101 to 400, or ≥ 400. Relative risk regression analysis was used to assess the association between fat depots and CAC., Results: There were modest correlations between EAT (r = 0.58), PAT (r = 0.47), SAT (r = 0.34), and CAC (P < .01). EAT, PAT, and SAT increased proportionally with the severity of CAC in both genders (P < .05). After adjustment for cardiovascular risk factors and body mass index, the relative risks for each standard deviation increase in EAT, PAT, and SAT were 3.3 (95% confidence interval, 1.9-5.6), 2.7 (95% confidence interval, 1.6-3.9), and 2.6 (95% confidence interval, 1.5-4.4) for CAC ≥ 100 compared to CAC 0, respectively (P < .05). The area under the receiver-operating characteristic curve to predict CAC ≥ 100 was higher in each fat depot compared to Framingham risk score, and addition of fat depots to Framingham risk score provided maximum prognostication value to detect CAC ≥ 100., Conclusions: Increased EAT, PAT, and SAT are associated with the severity of CAC independent of risk factors., (Published by Elsevier Inc.)

Background: Atherosclerotic changes within the coronary artery wall can affect vessel distensibility., Objective: This study evaluated the relationship between the coronary distensibility index (CDI) and the severity of coronary artery disease (CAD) measured by computed tomographic angiography (CTA)., Methods: One hundred thirteen subjects, age 63 +/- 10 years, 32% women, who underwent coronary artery calcium (CAC) scanning and CTA, were studied. Early diastolic and mid diastolic (MD) cross-section area (CSA) of the left anterior descending (LAD) artery were measured 5 mm distal to the left main bifurcation. CDI was defined as Deltalumen CSA/[lumen CSA in MD x estimated central pulse pressure (eCPP)] x 10(3) {eCPP = 0.77 x peripheral pulse pressure}. LAD diameter measured by CTA and quantitative coronary angiography (QCA) was compared in 19 subjects without CAD. CAD was defined as normal (no stenosis and CAC 0), mild (stenosis or= 70%) on CTA., Results: Excellent correlation was observed between CTA and QCA measured by CDI (r(2) = 0.96, P = 0.0001). CDI decreased from normal coronaries (6.75 +/- 1.43) to arteries with mild (5.78 +/- 1.45), moderate (3.96 +/- 1.06), and severe (3.31 +/- 1.06) disease (P = 0.004). The risk factor adjusted odds ratio of lowest versus 2 upper tertiles of CDI was 1.28 for mild, 8.47 for moderate, and 10.59 for severe CAD compared with the normal cohort. The area under the ROC curve to predict obstructive CAD (stenosis >or= 50%) increased significantly from 0.71 to 0.84 by addition of CDI to CAC (P < 0.05)., Conclusion: CTA-measured CDI is inversely related to the severity of CAD independent of age, sex, cardiovascular risk factors, and CAC., (Copyright 2010 Society of Cardiovascular Computed Tomography. All rights reserved.)

The relation between oxidative stress and coronary artery calcium (CAC) progression is currently not well described. The present study evaluated the relation among the biomarkers of oxidative stress, vascular dysfunction, and CAC. Sixty asymptomatic subjects participated in a randomized trial evaluating the effect of aged garlic extract plus supplement versus placebo and underwent measurement of CAC. The postcuff deflation temperature-rebound index of vascular function was assessed using a reactive hyperemia procedure. The content of oxidized phospholipids (OxPL) on apolipoprotein B-100 (apoB) particles detected by antibody E06 (OxPL/apoB), lipoprotein(a), IgG and IgM autoantibodies to malondialdehyde-low-density lipoprotein and apoB-immune complexes were measured at baseline and after 12 months of treatment. CAC progression was defined as an annual increase in CAC >15%. Vascular dysfunction was defined according to the tertiles of temperature-rebound at 1 year of follow-up. From baseline to 12 months, a strong inverse correlation was noted between an increase in CAC scores and increases in temperature-rebound (r(2) = -0.90), OxPL/apoB (r(2) = -0.85), and lipoprotein(a) (r(2) = -0.81) levels (p <0.0001 for all). The improvement in temperature-rebound correlated positively with the increases in OxPL/apoB (r(2) = 0.81, p = 0.0008) and lipoprotein(a) (r(2) = 0.79, p = 0.0001) but inversely with autoantibodies to malondialdehyde-low-density lipoprotein and apoB-immune complexes. The greatest CAC progression was noted with the lowest tertiles of increases in temperature-rebound, OxPL/apoB and lipoprotein(a) and the highest tertiles of increases in IgG and IgM malondialdehyde-low-density lipoprotein. In conclusion, the present results have documented a strong relation among markers of oxidative stress, vascular dysfunction, and progression of coronary atherosclerosis. Increases in OxPL/apoB and lipoprotein(a) correlated strongly with increases in vascular function and predicted a lack of progression of CAC., (Copyright 2010 Elsevier Inc. All rights reserved.)

Background: Studies of the relationship between patient self-reported angina symptoms using the Seattle Angina Questionnaire (SAQ) and angiographic findings after coronary artery bypass grafting surgery (CABG) are lacking. Nested within a randomized controlled trial, this prospective observational cohort comparison study aimed to assess which clinical characteristics and angiographic findings are associated with self-reported angina 1 year after CABG.Methods and Results: Patients from the ROOBY trial (Randomized On/Off Bypass) with protocol-specified 1-year post-CABG coronary angiography and SAQ assessments were included (n=1258). Patients reporting no angina (62.3%) within 4 weeks before the 1-year post-CABG study visit on the SAQ angina frequency domain were compared with patients reporting angina (37.7%). Multivariable modeling identified clinical variables and angiographic findings associated with angina. Sequential univariate and multivariable modeling found the following demographic and clinical factors were associated with angina after CABG: younger age, worse preoperative SAQ angina frequency score, smoking, diabetes mellitus, and pre-CABG depression. The only 1-year angiographic finding significantly associated with angina was incomplete revascularization of the left anterior descending (LAD) territory. Graft occlusions, incomplete revascularization of non-LAD territories, and ≥70% lesions in nonrevascularized native coronary arteries were not correlated with the presence or absence of angina. Further, only 30.6% of subjects reporting angina at 1 year had a residual major coronary artery stenosis of ≥70%.Conclusions: Self-reported angina 1 year after CABG is associated with younger age, worse baseline SAQ angina frequency score, smoking, diabetes mellitus, and depression. The only angiographic finding associated with angina was a poorly revascularized LAD territory. These results may help guide physicians when counseling patients on expected improvements in angina symptoms and in making decisions regarding the need for coronary angiography after CABG. Whether intensive treatment of these comorbidities improves post-CABG angina symptoms requires further study.Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT00032630. [ABSTRACT FROM AUTHOR]