Transfer of Cholesterol and Other Lipids From a Lipid Nanoemulsion to High-density Lipoprotein in Heart Transplant Patients

Background: Beyond the first year after a heart transplant (HT) procedure, patients often develop dyslipidemias, which may be implicated in the genesis of transplant coronary heart disease. High-density lipoprotein (HDL) has a several anti-atherogenic properties, but the status of HDL in HT patients is still controversial. Nonetheless, determination of HDL cholesterol concentration is not sufficient for evaluation of the overall HDL protective role. In this study, a fundamental functional property of HDL, the ability to simultaneously receive the major lipid classes, was tested in HT patients. Methods: Twenty HT patients and 20 healthy normolipidemic subjects paired for gender, age and body mass index were studied. Blood samples were collected after 12-hour fasting for determination of plasma lipids, glucose, paraxonase I (PON 1) activity, HDL diameter and transfer of labeled lipids from an artificial nanoemulsion to HDL. Results: Plasma triglycerides (159 +/- 63 vs 94 +/- 35 mg/dl) and glucose (104 +/- 20 vs 86 +/- 10 mg/dl) were greater in HT patients than in control subjects. HDL cholesterol was lower and HDL diameter was smaller in the HT group (HDL cholesterol: 44 +/- 11 vs 55 +/- 15 mg/dl; HDL diameter: 8.8 +/- 0.6 vs 9.0 +/- 1.2 nm). PON 1 activity did not differ (87 +/- 47 vs 75 +/- 37 nmol/min/ml). The transfer rates of free cholesterol and cholesteryl esters were diminished in HT patients (HT: 8.4 +/- 1.2% and 3.8 +/- 0.6%; controls: 9.7 +/- 1.9% and 4.7 +/- 1.2%, respectively). Conclusions: The transfer of free cholesterol and cholesteryl esters to HDL is diminished in HT patients; disturbance in the ability of HDL to receive lipids may affect the anti-atherogenic properties of the lipoprotein. J Heart Lung Transplant 2009;28:1075-80. Copyright (C) 2009 by the International Society for Heart and Lung Transplantation.

Cardiac MRI for Detection of Unrecognized Myocardial Infarction in Patients With End-Stage Renal Disease: Comparison With ECG and Scintigraphy

OBJECTIVE. The purposes of this study were to use the myocardial delayed enhancement technique of cardiac MRI to investigate the frequency of unrecognized myocardial infarction (MI) in patients with end-stage renal disease, to compare the findings with those of ECG and SPECT, and to examine factors that may influence the utility of these methods in the detection of MI. SUBJECTS AND METHODS. We prospectively performed cardiac MRI, ECG, and SPECT to detect unrecognized MI in 72 patients with end-stage renal disease at high risk of coronary artery disease but without a clinical history of MI. RESULTS. Fifty-six patients (78%) were men ( mean age, 56.2 +/- 9.4 years) and 16 (22%) were women ( mean age, 55.8 +/- 11.4). The mean left ventricular mass index was 103.4 +/- 27.3 g/m(2), and the mean ejection fraction was 60.6% +/- 15.5%. Myocardial delayed enhancement imaging depicted unrecognized MI in 18 patients (25%). ECG findings were abnormal in five patients (7%), and SPECT findings were abnormal in 19 patients (26%). ECG findings were false-negative in 14 cases and false-positive in one case. The accuracy, sensitivity, and specificity of ECG were 79.2%, 22.2%, and 98.1% (p = 0.002). SPECT findings were false-negative in six cases and false-positive in seven cases. The accuracy, sensitivity, and specificity of SPECT were 81.9%, 66.7%, and 87.0% ( not significant). During a period of 4.9-77.9 months, 19 cardiac deaths were documented, but no statistical significance was found in survival analysis. CONCLUSION. Cardiac MRI with myocardial delayed enhancement can depict unrecognized MI in patients with end-stage renal disease. ECG and SPECT had low sensitivity in detection of MI. Infarct size and left ventricular mass can influence the utility of these methods in the detection of MI.

Relation of Aortic Valve Calcium Detected by Cardiac Computed Tomography to All-Cause Mortality

Aortic valve calcium (AVC) can be quantified on the same computed tomographic scan as coronary artery calcium (CAC). Although CAC is an established predictor of cardiovascular events, limited evidence is available for an independent predictive value for AVC. We studied a cohort of 8,401 asymptomatic subjects (mean age 53 10 years, 69% men), who were free of known coronary heart disease and were undergoing electron beam computed tomography for assessment of subclinical atherosclerosis. The patients were followed for a median of 5 years (range 1 to 7) for the occurrence of mortality from any cause. Multivariate Cox regression models were developed to predict all-cause mortality according to the presence of AVC. A total of 517 patients (6%) had AVC on electron beam computed tomography. During follow-up, 124 patients died (1.5%), for an overall survival rate of 96.1% and 98.7% for those with and without AVC, respectively (hazard ratio 3.39, 95% confidence interval 2.09 to 5.49). After adjustment for age, gender, hypertension, dyslipidemia, diabetes mellitus, smoking, and a family history of premature coronary heart disease, AVC remained a significant predictor of mortality (hazard ratio 1.82, 95% confidence interval 1.11 to 2.98). Likelihood ratio chi-square statistics demonstrated that the addition of AVC contributed significantly to the prediction of mortality in a model adjusted for traditional risk factors (chi-square = 5.03, p = 0.03) as well as traditional risk factors plus the presence of CAC (chi-square = 3.58, p = 0.05). In conclusion, AVC was associated with increased all-cause mortality, independent of the traditional risk factors and the presence of CAC. (C) 2010 Published by Elsevier Inc. (Am J Cardiol 2010;106:1787-1791)

Transfusion Requirements After Cardiac Surgery The TRACS Randomized Controlled Trial

Context Perioperative red blood cell transfusion is commonly used to address anemia, an independent risk factor for morbidity and mortality after cardiac operations; however, evidence regarding optimal blood transfusion practice in patients undergoing cardiac surgery is lacking. Objective To define whether a restrictive perioperative red blood cell transfusion strategy is as safe as a liberal strategy in patients undergoing elective cardiac surgery. Design, Setting, and Patients The Transfusion Requirements After Cardiac Surgery (TRACS) study, a prospective, randomized, controlled clinical noninferiority trial conducted between February 2009 and February 2010 in an intensive care unit at a university hospital cardiac surgery referral center in Brazil. Consecutive adult patients (n=502) who underwent cardiac surgery with cardiopulmonary bypass were eligible; analysis was by intention-to-treat. Intervention Patients were randomly assigned to a liberal strategy of blood transfusion (to maintain a hematocrit >= 30%) or to a restrictive strategy (hematocrit >= 24%). Main Outcome Measure Composite end point of 30-day all-cause mortality and severe morbidity (cardiogenic shock, acute respiratory distress syndrome, or acute renal injury requiring dialysis or hemofiltration) occurring during the hospital stay. The noninferiority margin was predefined at -8% (ie, 8% minimal clinically important increase in occurrence of the composite end point). Results Hemoglobin concentrations were maintained at a mean of 10.5 g/dL(95% confidence interval [CI], 10.4-10.6) in the liberal-strategy group and 9.1 g/dL (95% CI, 9.09.2) in the restrictive-strategy group (P<.001). A total of 198 of 253 patients (78%) in the liberal-strategy group and 118 of 249 (47%) in the restrictive-strategy group received a blood transfusion (P<.001). Occurrence of the primary end point was similar between groups (10% liberal vs 11% restrictive; between-group difference, 1% [95% CI, -6% to 4%]; P=.85). Independent of transfusion strategy, the number of transfused red blood cell units was an independent risk factor for clinical complications or death at 30 days (hazard ratio for each additional unit transfused, 1.2 [95% CI, 1.1-1.4]; P=.002). Conclusion Among patients undergoing cardiac surgery, the use of a restrictive perioperative transfusion strategy compared with a more liberal strategy resulted in noninferior rates of the combined outcome of 30-day all-cause mortality and severe morbidity. Trial Registration clinicaltrials.gov Identifier: NCT01021631 JAMA. 2010; 304(14):1559-1567 www.jama.com

Preferential use of nonreversed vein grafts in above-knee femoropopliteal bypasses for critical ischemia: Midterm outcome

We evaluated nonreversed vein grafts in above-knee bypasses for chronic critical limb ischemia in a retrospective study with intention-to-treat analysis in patients who underwent above-knee bypass grafting. During a 4-year period, 51 patients (men, 32; women, 19; mean age 66 years) with 53 critically ischemic lower extremities underwent above-knee femoropopliteal bypass grafting. The follow-up evaluation consisted of clinical examination, assessment of the ankle- brachial systolic blood pressure index, and, whenever necessary, duplex scanning. Three ( 5.7%) deaths occurred within 30 days, two from myocardial infarction and one from an undetermined cause. The 2-year cumulative success rate was 82.5 +/- 9.6% for primary patency, 84.6 +/- 8.9% for secondary patency, 90.1 +/- 7.3% for tertiary patency, 86.9 +/- 7.6% for limb salvage, 77.7 +/- 8.4% for survival, 68.0 +/- 11.1% for composite patency, and 68.4 +/- 9.3% for amputation- free survival; the corresponding estimates for vein grafts alone were 86.6 +/- 9.2%, 88.9 +/- 8.6%, 89.0 +/- 8.5%, 88.1 +/- 8.1%, 81.1 +/- 9.1, 76.8 +/- 11.1%, and 72.6 +/- 10.2%. Three prosthetic grafts failed and were replaced with an arm vein graft. Nonreversed vein bypass grafts in above- knee revascularization of critically ischemic limbs are justified.

Characterization of high density lipoprotein particles in familial apolipoprotein A-I deficiency

Our aim was to characterize HDL subspecies and fat-soluble vitamin levels in a kindred with familial apolipoprotein A-I (apoA-I) deficiency. Sequencing of the APOA1 gene revealed a nonsense mutation at codon 22, Q[22] X, with two documented homozygotes, eight heterozygotes, and two normal subjects in the kindred. Homozygotes presented markedly decreased HDL cholesterol levels, undetectable plasma apoA-1, tuboeruptive and planar xanthomas, mild corneal arcus and opacification, and severe premature coronary artery disease. In both homozygotes, analysis of HDL particles by two-dimensional gel electrophoresis revealed undetectable apoA-I, decreased amounts of small a-3 migrating apoA-II particles, and only modestly decreased normal amounts of slow a migrating apoA-IV- and apoE-containing HDL, while in the eight heterozygotes, there was loss of large alpha-1 HDL particles. There were no significant decreases in plasma fat-soluble vitamin levels noted in either homozygotes or heterozygotes compared with normal control subjects. Our data indicate that isolated apoA-I deficiency results in marked HDL deficiency with very low apoA-II alpha-3 HDL particles, modest reductions in the separate and distinct plasma apoA-IV and apoE HDL particles, tuboeruptive xanthomas, premature coronary atherosclerosis, and no evidence of fat malabsorption.

Most of the patients presenting myocardial infarction would not be eligible for intensive lipid-lowering based on clinical algorithms or plasma C-reactive protein

Objective: The study we assessed how often patients who are manifesting a myocardial infarction (MI) would not be considered candidates for intensive lipid-lowering therapy based on the current guidelines. Methods: In 355 consecutive patients manifesting ST elevation MI (STEMI), admission plasma C-reactive protein (CRP) was measured and Framingham risk score (FRS), PROCAM risk score, Reynolds risk score, ASSIGN risk score, QRISK, and SCORE algorithms were applied. Cardiac computed tomography and carotid ultrasound were performed to assess the coronary artery calcium score (CAC), carotid intima-media thickness (cIMT) and the presence of carotid plaques. Results: Less than 50% of STEMI patients would be identified as having high risk before the event by any of these algorithms. With the exception of FRS (9%), all other algorithms would assign low risk to about half of the enrolled patients. Plasma CRP was <1.0 mg/L in 70% and >2 mg/L in 14% of the patients. The average cIMT was 0.8 +/- 0.2 mm and only in 24% of patients was >= 1.0 mm. Carotid plaques were found in 74% of patients. CAC > 100 was found in 66% of patients. Adding CAC >100 plus the presence of carotid plaque, a high-risk condition would be identified in 100% of the patients using any of the above mentioned algorithms. Conclusion: More than half of patients manifesting STEMI would not be considered as candidates for intensive preventive therapy by the current clinical algorithms. The addition of anatomical parameters such as CAC and the presence of carotid plaques can substantially reduce the CVD risk underestimation. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Intramyocardial transplantation of fibroblasts expressing vascular endothelial growth factor attenuates cardiac dysfunction

In this study, we analyzed whether transplantation of cardiac fibroblasts (CFs) expressing vascular endothelial growth factor (VEGF) mitigates cardiac dysfunction after myocardial infarction (MI) in rats. First, we observed that the transgene expression lasts longer (45 vs 7 days) when fibroblasts are used as vectors compared with myoblasts. In a preventive protocol, induction of cardiac neovascularization accompanied by reduction in myocardial scar area was observed when cell transplantation was performed 1 week before ischemia/reperfusion and the animals analyzed 3 weeks later. Finally, the therapeutic efficacy of this approach was tested injecting cells in a fibrin biopolymer, to increase cardiac retention, 24 h post-MI. After 4 weeks, an increase in neovascularization and a decrease in myocardial collagen were observed only in rats that received cells expressing VEGF. Basal indirect or direct hemodynamic measurements showed no differences among the groups whereas under pharmacological stress, only the group that received cells expressing VEGF showed a significant reduction in end-diastolic pressure and improvement in stroke volume and cardiac work. These results indicate that transplantation of CFs expressing VEGF using fibrin biopolymer induces neovascularization and attenuates left ventricle fibrosis and cardiac dysfunction in ischemic heart. Gene Therapy (2010) 17, 305-314; doi:10.1038/gt.2009.146; published online 10 December 2009

Association between glutathione S-transferase polymorphisms and triglycerides and HDL-cholesterol

Objective: Null genotypes of glutathione S-transferase (GSTs) exhibit absence of enzymatic activity and are hypothesized to modulate an increased risk of developing cardiovascular disease. The aim of this study was to identify the potential association between GSTM1 and GSTT1 deleted polymorphisms with cardiovascular risk factors and coronary atherosclerosis in two independent urban populations. Methods and results: Genotype distribution of GSTM1 and GSTT1 deleted polymorphism were examined in a sample of 1577 individuals from the general population and a replication sample of 871 individuals submitted to coronary angiography. Triglycerides, HDL-cholesterol and the triglycerides/HDL ratio were significantly associated with a double-deleted genotype in individuals from the general population. These findings were replicated in a second, independent, population of individuals submitted to coronary angiography. In addition, coronary artery disease severity was also associated with GSTs genotypes and the risk conferred from GSTs genotype was mainly due to triglycerides/HDL ratio information. Conclusions: The data suggest that the presence of a double deletion genotypes of the GSTM1 and GSTT1 genes is associated with hypertriglyceridemia and low HDL-cholesterol levels in humans. These novel findings may provide a new unexplored link between lipid metabolism and GST homeostasis. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

Native LDL-Cholesterol Mediated Monocyte Adhesion Molecule Overexpression is Blocked by Simvastatin

Aim of the study This study sought to evaluate the effect of nLDL concentrations on monocyte adhesion molecule expression in hypercholesterolemic patients with stable corollary artery disease (CAD) and to determine whether lipid-lowering therapy with simvastatin Would change this effect. Methods Blood samples from patients with hypercholesterolemia (mean LDL 152 mg/dL) and CAD (HC, n = 23) were collected before and after a 12-week treatment with 40 mg of simvastatin. Healthy individuals (mean LDL 111 mg/dL) were used as controls (CT, n = 15). Isolated nLDL, at a fixed concentration of 100 mg/dL, was added to monocyte suspensions obtained before and after the simvastatin treatment. Monocyte activation was determined by changes in cellular adhesion molecule expression. Results In response to nLDL, CD11b and CD14 adhesion molecule expression was higher in HC patients than in CT patients before treatment (174.2+/-8.4 vs 102.2+/-6.3, P<0.03 and 140.4+/-5.0 vs 90.4+/-6.7, P<0.04). After simvastatin treatment, CD11b expression decreased to 116.9+/-12.5 (P< 0.03) and CD14 expression to 107.5+/-6.2 (P<0.04). Alternatively, L-selectin expression was lower in HC patients than in CT patients before therapy (46.0+/-3.5 vs 62.1+/-5.5, P<0.04), and it increased markedly after lipid reduction to 58.7+/-5.0 (P<0.04 vs baseline). After simvastatin treatment, LDL was reduced to mean 101.5 mg/dL. Conclusions These data demonstrate that monocytes from HC patients are more prone to marked nLDL-mediated changes of adhesion molecule expression than monocytes from controls. Simvastatin is capable of inhibiting such nLDL effects. This proinflammatory response to nLDL may have a role in the early onset of atherosclerosis.

Multicenter double blind trial of autologous bone marrow mononuclear cell transplantation through intracoronary injection post acute myocardium infarction - MiHeart/AMI study

Background: Myocardial infarction remains as a major cause of mortality worldwide and a high rate of survivors develop heart failure as a sequel, resulting in a high morbidity and elevated expenditures for health system resources. We have designed a multicenter trial to test for the efficacy of autologous bone marrow (ABM) mononuclear cell (MC) transplantation in this subgroup of patients. The main hypothesis to be tested is that treated patients will have a significantly higher ejection fraction (EF) improvement after 6 months than controls. Methods: A sample of 300 patients admitted with ST elevation acute myocardial infarction (STEMI) and left ventricle (LV) systolic dysfunction, and submitted to successful mechanical or chemical recanalization of the infarct-related coronary artery will be selected for inclusion and randomized to either treated or control group in a double blind manner. The former group will receive 100 x 106 MC suspended in saline with 5% autologous serum in the culprit vessel, while the latter will receive placebo (saline with 5% autologous serum). Implications: Many phase I/II clinical trials using cell therapy for STEMI have been reported, demonstrating that cell transplantation is safe and may lead to better preserved LV function. Patients with high risk to develop systolic dysfunction have the potential to benefit more. Larger randomized, double blind and controlled trials to test for the efficacy of cell therapies in patients with high risk for developing heart failure are required.

Subclinic atherosclerosis and cardiovascular risk factors in HIV-infected children: PERI study

Objectives To compare carotid intima-media thickness (cIMT) of children and adolescents with and without HIV infection and to determine associations among independent socio-demographic, clinical or cardiovascular variables and cIMT in HIV-infected children and adolescents. Patients and methods This is a matched case-control study comparing 83 HIV-infected and 83 healthy children and adolescents. Clinical and laboratorial parameters, cIMT and echocardiogram were measured. Results The cIMT was higher in HIV-infected individuals (median 480 mu m; interquartile range 463-518 mu m) compared with controls (426 mu m; range 415-453 mu m, P < 0.001). In addition, the HIV-infected group showed higher levels of high-sensitive C-reactive protein (medians 1.0 mg/l vs. 0.4 mg/l, P < 0.001), glycated hemoglobin (6.1 +/- 0.9 vs. 5.7 +/- 0.8%, P= 0.028) and triglycerides (medians 0.9 vs. 0.8 mmol/l, P= 0.031). Finally, this group showed lower levels of total and high-density lipoprotein-cholesterol. After multivariate analysis, increased cIMT was positively associated with stavudine use [odds ratio (OR): 18.9, P=0.005], left atrial/aorta index (OR: 15.6, P=0.019), suprailiac skinfold (OR: 7.9, P=0.019), tachypnea (OR: 5.9, P=0.031), CD8 lymphocyte count (OR: 5.7, P=0.033) and CD4 T-lymphocyte count (OR: 5.5, P=0.025). cIMT increment was negatively associated with total cholesterol (OR: 0.2, P=0.025) and with CD8 zenith (OR: 0.1, P=0.007). Conclusion In this sample of children and adolescents, having HIV infection was associated with increased cIMT and elevated prevalence of cardiovascular risk factors. These findings suggest that this group should be included in cardiovascular prevention programs.

Adult rats are more sensitive to the vascular effects induced by hyperhomocysteinemia than young rats

We aimed to investigate the vascular effects of hyperhomocysteinemia (HHcy) on carotid arteries from young and adult rats. With this purpose young and adult rats received a solution of DL-homocysteine-thiolactone (1 g/kg body weight/day) in the drinking water for 7, 14 and 28 days. Increase on plasma homocysteine occurred in young and adult rats treated with DL-homocysteine-thiolactone in all periods. Vascular reactivity experiments using standard muscle bath procedures showed that HHcy enhanced the contractile response of endothelium-intact, carotid rings to phenylephrine in both young and adult rats. However, in young rats, the increased phenylephrine-induced contraction was observed after hyperhomocysteinemia for 14 and 28 days, whereas in adult rats this response was already apparent after 7 day treatment. HHcy impaired acetylcholine-induced relaxation in arteries from adult but not young rats. The contraction induced by phenylephrine in carotid arteries in the presence of Y-27632 was reversed to control values in arteries from young but not adult rats with hyperhomocysteinemia. HHcy did not alter the contraction induced by CaCl(2) in carotid arteries from young rats, but enhanced CaCl(2)-induced contraction in the arteries from adult rats. HHcy increased the basal levels of superoxide anion in arteries from both groups. Finally, HHcy decreased the basal levels of nitrite in arteries from adult but not young rats. The major new finding of the present work is that arteries from young rats are more resistant to vascular changes evoked by HHcy than arteries from adult rats. Also, we verified that the enhanced vascular response to phenylephrine observed in carotid arteries of DL-homocysteine thiolactone-treated rats is mediated by different mechanisms in young and adult rats. (C) 2010 Published by Elsevier Inc.

Metabolism of triglyceride-rich lipoproteins and lipid transfer to high-density lipoprotein in young obese and normal-weight patients with polycystic ovary syndrome

Objective: To clarify whether the metabolism of triglyceride-rich lipoproteins and lipid transfer to high-density lipoprotein (HDL) are altered in patients with polycystic ovary syndrome (PCOS). Design: Case control study. Setting: Endocrinology clinics. Patient(s): Eight normal-weight (NW) and 15 obese (013) patients with PCOS were compared with 10 NW and 10 Ob women without PCOS paired for age and body mass index. Intervention(s): Determination of triglyceride-rich lipoprotein metabolism and lipid transfer to HDL. Main Outcome Measure(s): Participants were injected triglyceride-rich emulsions labeled with (14)C-cholesteryl esters and (3)H-triglycerides and the fractional clearance rate (FCR, in min(-1)) of labels was determined. Lipid transfer from artificial nanoemulsions to HDL was performed by incubating radioactively labeled lipid nanoemulsions with plasma during 1 hour, followed by radioactive counting of HDL-containing supernatant after chemical precipitation. Result(s): Lipolysis estimated by triglyceride FCR was equal in PCOS groups (NW = 0.043 +/- 0.032, Ob = 0.033 +/- 0.009) and respective controls (NW = 0.039 +/- 0.015, Ob = 0.044 +/- 0.019). However, the remnant removal as estimated by cholesteryl ester FCR was reduced in both PCOS groups (NW = 0.005 +/- 0.006, Ob = 0.005 +/- 0.005) compared with controls (NW = 0.016 +/- 0.006, Ob = 0.011 +/- 0.072). Lipid transfer rates were not different among groups, but triglyceride transfer rates were positively correlated with homeostasis model assessment estimate of insulin resistance in PCOS. Conclusion(s): PCOS patients showed decreased removal of atherogenic remnants even when fasting glucose was <100 mg/dL. This reinforces the usefulness of the measures taken to prevent cardiovascular events in PCOS patients. (Fertil Steril (R) 2010;93:1948-56. (C)2010 by American Society for Reproductive Medicine.)