Biomedical subjects

Mohamed Amrani

Publications and source records attributed to Mohamed Amrani.

At least 19 recordsLinked to original sources

PubMed2006

Role of human valve interstitial cells in valve calcification and their response to atorvastatin.

BACKGROUND: Calcific aortic valve stenosis is a common disease in the elderly and is characterized by progressive calcification and fibrous thickening of the valve, but the cellular and molecular mechanisms are not fully understood. We hypothesized that human valve interstitial cells (ICs) are able to differentiate into osteoblast-like cells through the influence of defined mediators and that this process can be modulated pharmacologically. METHODS AND RESULTS: To test this hypothesis, we treated primary cultures of human aortic valve ICs with osteogenic media, bone morphogenic proteins ([BMPs] BMP-2, BMP-4, and BMP-7), and tissue growth factor-beta ([TGF-beta] TGF-beta1 and TGF-beta3) for 21 days. These mediators induced osteoblast differentiation of valve ICs by significantly increasing the activity and expression of alkaline phosphatase ([ALP] P<0.001). A cytokine protein array revealed that atorvastatin treatment (100 micromol/L) of human valve ICs caused a downregulation in levels of expression of BMP-2, BMP-6, TGF-beta1, and TGF-beta3 after 24 hours. In addition, human valve ICs treated with atorvastatin in the presence of osteogenic media showed a significant reduction in ALP activity in comparison to cells treated with osteogenic media only (P=<0.001). This was further confirmed with immunocytochemical staining of valve ICs, whereby atorvastatin markedly reduced the expression of ALP and osteocalcin induced by osteogenic media in comparison to untreated cells. CONCLUSIONS: These findings suggest that human valve ICs are capable of osteoblastic differentiation, by potential mediators which can be pharmacologically targeted by atorvastatin.

Aged↗

PubMed2006

A novel role of extracellular nucleotides in valve calcification: a potential target for atorvastatin.

BACKGROUND: Calcific aortic valve disease is a common condition and is associated with inflammatory changes and expression of osteoblast-like cell phenotypes, but the cellular mechanisms are unclear. Recent studies identified extracellular ATP and P2Y receptor cascade as important regulators of bone remodeling, whereas its breakdown product, adenosine, is known to have anti-inflammatory properties. We hypothesize that extracellular ATP and adenosine have important roles in regulating osteoblast differentiation in human valve interstitial cells, and that this can be a potential target for therapy. Method and Results- Primary cultures of human valve interstitial cells (ICs) treated for 21 days with osteogenic media, ATP, and ATP-gamma-S (a stable agonist of the P2Y receptor) revealed a significant increase in alkaline phosphatase (ALP) (an osteoblast marker) activity and expression as measured using spectrophotometric assay and immunocytochemistry staining. Valve ICs treated with adenosine alone did not cause an increase in ALP activity; however, adenosine treatment decreased the ALP activity and expression induced by osteogenic media after 21 days of incubation. In addition, atorvastatin inhibited the activity of ALP induced by ATP in human valve ICs, and enzyme studies revealed that atorvastatin upregulated the breakdown of extracellular ATP into adenosine in human valve ICs after 24-hour treatment. CONCLUSIONS: These findings identify a novel role for extracellular nucleotides in inducing osteoblast differentiation in human valve ICs in vitro and provide a potential therapeutic target for preventing the disease progression.

5'-Nucleotidase↗

PubMed2006

Effect of off-pump coronary artery bypass surgery on clinical, angiographic, neurocognitive, and quality of life outcomes: randomised controlled trial.

OBJECTIVE: To compare the clinical, angiographic, neurocognitive, and quality of life outcomes of off-pump coronary artery bypass surgery with conventional coronary artery bypass grafting surgery using cardiopulmonary bypass. DESIGN: Randomised controlled clinical trial. SETTING: Tertiary cardiothoracic centre in Middlesex, England. PARTICIPANTS: 168 patients (27 women) requiring primary isolated coronary artery bypass grafting surgery. INTERVENTIONS: Patients were randomised to conventional coronary artery bypass grafting surgery using cardiopulmonary bypass (n = 84) or off-pump coronary artery bypass surgery (n = 84), carried out by one surgeon. Angiographic examination was carried out at three months postoperatively. Neurocognitive tests were carried out at baseline and at six weeks and six months postoperatively. MAIN OUTCOME MEASURES: Clinical outcome, graft patency at three months, neurocognitive function at six weeks and six months, and health related quality of life. RESULTS: Graft patency was evaluated by angiography in 151 (89.9%) patients and was similar between the cardiopulmonary bypass and off-pump groups (risk difference - 1%, 95% confidence interval - 5% to 4%), with the off-pump group considered the treatment group. Patients in the off-pump group required fewer blood transfusions (1.7 units v 1.0 unit, P = 0.02), shorter duration of mechanical ventilation (7.7 hours v 3.9 hours, P = 0.03), and shorter hospital stay (10.8 days v 8.9 days). Scores for neurocognitive function showed a significant difference in three memory subtests at six weeks and two memory subtests at six months in favour of the off-pump group. CONCLUSIONS: Patients who underwent off-pump coronary artery bypass surgery showed similar patency of grafts, better clinical outcome, shorter hospital stay, and better neurocognitive function than patients who underwent conventional coronary artery bypass grafting surgery using cardiopulmonary bypass.

Cognition Disorders↗

PubMed2006

Determining phosphorus release rates to runoff from selected Alberta soils using laboratory rainfall simulation.

Phosphorus losses from agricultural land can cause accelerated eutrophication of surface water bodies. This study evaluated the use of soil test phosphorus (STP) levels to predict dissolved inorganic phosphorus (DIP) concentrations in runoff water from agricultural soils using laboratory rainfall simulation. The objectives of this study were to determine (i) to what extent STP concentrations can be used as a basis to predict P losses from Alberta soils and (ii) how extended rainfall simulation run times affected DIP losses. Soil samples collected from a total of 38 field sites, widely scattered throughout the southern half of Alberta, were subjected to rainfall simulation in the laboratory. The STP concentrations were determined using Miller-Axley, Norwest, Kelowna, Modified Kelowna Mehlich-III, and distilled water extraction methods. Each rainfall simulation event lasted for at least 90 min. Runoff samples were collected in time series for the duration of each simulation, during two distinct runoff intervals: (i) for the first 30 min of continuous runoff (T30) and (ii) for 40 min during runoff equilibrium (Teq). For all the STP extractants and both runoff intervals, the relationship with DIP-flow-weighted mean concentration (FWMC) was linear and highly significant with r2 values ranging from 0.74 to 0.96. However, the slopes of the resulting regression lines were, on average, 1.85 times greater for the T30 runoff interval over those computed for the Teq interval. Thus experimental methodology greatly influenced regression parameters, suggesting that more work was needed to verify these relationships under natural conditions. In addition, with many of the r2 values greater than 0.90 there would be little, if any, benefit derived by including soil properties in regression analysis.

Alberta↗

PubMed2006

A technical failure changes a Y-graft into a C-conduit causing steal syndrome.

Y-grafting is a common coronary grafting technique for performing composite coronary grafts. The outcome and efficacy of this technique have not been studied in detail in the literature. We report a case of an occlusion in the proximal limb of a Y-graft, changing it into a C-shaped conduit and causing a steal syndrome. Our aim is to raise the level of caution when performing this type of composite graft and to suggest how this complication can be managed postoperatively.

Aged, 80 and over↗

PubMed2006

Effect of myocardial reperfusion on the release of nitric oxide after regional ischemia: an experimental model of beating-heart surgery.

Off-pump coronary artery bypass surgery is increasing in popularity worldwide. However, very little is known about the effect of regional myocardial ischemia-reperfusion on nitric oxide release. In an animal model mimicking off-pump bypass, male Sprague-Dawley rats (350-450 g) were mechanically ventilated under general anesthesia. After left lateral thoracotomy, the animals underwent occlusion of either the left anterior descending artery (for 3, 5, 75, 10, 12.5, 15, or 20 minutes) or the circumflex artery (for 5, 10, or 15 minutes). Twenty-four hours after reperfusion, heart tissue was stained for determination of the area at risk and the infarcted area. Blood samples obtained before ischemia, 10 minutes after reperfusion, and 24 hours after reperfusion were analyzed for plasma concentrations of nitric oxide. After occlusion of the left anterior descending artery, the size of the infarcted area increased dramatically as the duration of occlusion increased, and was significantly larger after 12.5, 15, or 20 minutes of occlusion than after 3 minutes. After occlusion of the circumflex artery, the size of the infarcted area increased steadily and was significantly larger after 15 minutes of occlusion than after 5 minutes. There was no significant correlation between the duration of coronary occlusion and the plasma concentration of nitric oxide: 10 minutes after reperfusion, this concentration was significantly lower than that before ischemia, but it was twice the baseline level 24 hours after reperfusion. We concluded that the duration of regional ischemia did not affect the plasma concentration of nitric oxide in the systemic circulation.

Animals↗

PubMed2005

Three-dimensional in vivo characterization of calcification in native valves and in Freestyle versus homograft aortic valves.

OBJECTIVE: This article describes a novel interactive method for quantitative evaluation of calcium deposits in the aortic valve by means of electron beam tomography data fusion technique. METHODS: The technique relied on the use of hierarchic 3-dimensional free-form volume registration with fast global optimization between normally acquired and contrast-enhanced electron beam tomographic volume. A total of 66 contrast-enhanced electron beam tomographic scans of the aortic root were performed in 27 patients, 10 with native aortic valve disease (group A) and 17 from a prospective randomized trial of aortic root replacement (group B, 9 Freestyle grafts [Medtronic, Inc, Minneapolis, Minn] and 8 homografts). To validate the in vivo electron beam tomographic measurements, 5 patients from group A underwent electron beam tomographic scans before the operation and then had their own valves, explanted at the time of surgery, analyzed for calcium quantification by ex vivo electron beam tomography. RESULTS: In group A, the mean (+/- SE) calcification score was 6560 +/- 2388, which correlated with peak gradients measured at echocardiography ( r = 0.93, P = .02). In group B, the mean (+/- SE) calcification score was 168 +/- 27, showing a tendency toward a lower calcification for Freestyle valves than for homografts at 2 years after implantation ( P = .052). A mean variability of 6% was found between in vivo electron beam tomographic scores of calcification and those measured on valve specimens after explantation. CONCLUSION: We describe a novel method to characterize the degree and location of calcification in both native valves and postoperative valve implants. The technique may be useful in the management of patients with aortic valve disease and has potential as a screening tool for high-risk patients to diagnose early valve calcification and possibly institute corrective measures.

Aged↗

PubMed2004

Off-pump myocardial revascularization is associated with less incidence of stroke in elderly patients.

Several recent studies have highlighted the potential benefits of using off-pump coronary artery bypass (OPCAB) surgery, particularly in high-risk patients. The aim of this meta-analysis is to assess the effect of OPCAB on the incidence of stroke compared with coronary artery bypass grafting using cardiopulmonary bypass (CPB) in elderly patients. We performed a meta-analysis of all observational studies, published in MEDLINE between 1999 and 2002 and a comparison between the OPCAB and CPB techniques in elderly patients was performed with the outcome of interest being the incidence of stroke. Elderly patients were defined as those aged 70 years or older. Nine studies are included in the meta-analysis. The total number of subjects included was 4,475 patients, of which, 1,253 underwent OPCAB (28%) and 3,222 (72%) underwent CPB. The meta-analysis showed that the OPCAB technique was associated with significantly lower incidence of stroke in elderly patients compared with the CPB technique (1% vs 3%), with an odds ratio of 0.38% to 95% (CI, 0.22 to 0.65). We did not identify any significant heterogeneity and funnel plot asymmetry between the studies included in the meta-analysis. Meta-regression analysis including variables predicting stroke, mortality, and study characteristics did not show any associations affecting the calculated odds ratio of stroke. Despite the fact that this is a meta-analysis of observational studies and adjustment for differences in baseline risk factors between OPCAB and CPB patients was not possible, we believe that this study suggests that the OPCAB technique might be associated with reduced incidence of stroke in the elderly patients undergoing coronary artery bypass grafting.

Aged↗

PubMed2004

Do off-pump techniques reduce the incidence of postoperative atrial fibrillation in elderly patients undergoing coronary artery bypass grafting?

BACKGROUND: Atrial fibrillation is the most common postoperative complication in patients undergoing coronary artery bypass grafting (CABG) with advancing age having been shown to have a significant association with its incidence. This study aims to assess whether off-pump coronary artery bypass (OPCAB) reduces the incidence of atrial fibrillation in elderly patients. METHODS: A meta-analysis of all observational studies reporting a comparison between the two techniques in elderly patients (> 70 years) between 1999-2003 was performed. The primary outcome of interest was the incidence of postoperative atrial fibrillation. The quality of each study was evaluated by examining three items: patient selection, matching of the off-pump and cardiopulmonary bypass patient groups, and assessment of outcome. Meta-regression analysis was undertaken to see the effects of study size and quality on the calculated odds ratio. RESULTS: Eight studies fulfilled our inclusion criteria, all of which were nonrandomized. In total the studies identified 3017 subjects, of which 764 had off-pump surgery (25%) and 2253 underwent cardiopulmonary bypass (75%). Meta-analysis showed that after off-pump surgery there was a significantly lower incidence of postoperative atrial fibrillation in these patients (odds ratio 0.70, 95% confidence interval [CI] 0.56-0.89). Meta-regression analysis including study characteristics did not show any associations affecting the calculated odds ratio of atrial fibrillation. CONCLUSIONS: Our study demonstrates a reduced incidence of postoperative atrial fibrillation in an elderly population with off-pump as compared with cardiopulmonary bypass techniques. We appreciate, however, that our statistical analysis uses nonrandomized published data and that the results must be treated with caution. If this finding is confirmed by a large-scale randomized trial, it has significant implications on the operative strategy employed for this patient group.

Aged↗

PubMed2004

Methodological approach in adopting off-pump coronary artery bypass surgery in a British cardiothoracic unit: Harefield experience.

The theoretical and practical disadvantages of coronary artery bypass graft surgery using cardiopulmonary bypass with cardioplegic arrest are well reported in the literature. Encouraged by our work and others, we adopted a systematic approach to the application of off-pump coronary artery bypass surgery. We aimed to validate the non-selective use of the off-pump technique in all patients and assess the outcome in specific patient groups including: patients with ischaemic left ventricular dysfunction, female and high-risk patients. We investigated specific technical details related to off-pump surgery including: the potential effect of the distortion of the mitral valve on haemodynamic stability intraoperatively and the feasibility of sequential coronary artery bypass grafting using the off-pump technique. We also compared the outcome to the national United Kingdom performance in a risk-stratified manner. An extensive retrospective data review for comparative analysis of outcome was carried out at both local and multi-centre levels. This showed that off-pump surgery was feasible for all patients, and provided a better outcome in patients with ischaemic left ventricular dysfunction, female and high-risk patients. The distortion of the mitral valve contributed to the haemodynamic instability. In conclusion, off-pump surgery is safe and provides better outcome in specific patient groups.

Aged↗

PubMed2004

The role of arterial grafts in coronary artery bypass grafting: an update.

Based on the legacy of the success of the internal thoracic artery as a bypass conduit for myocardial revascularization, the effort to achieve total arterial revascularization continued to evolve in the last 2 decades. Arterial conduits were used as alternatives to saphenous vein for coronary artery bypass grafting. In this review we attempted to assess the success and failure of these conduits and the current trend in myocardial revascularization.

Arteries↗

PubMed2004

Cerivastatin does not prevent oxidative injury of human aortic endothelial cells.

The anti-atherogenic properties of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) have been well established in several circulatory beds. Increasing evidence suggests that statins may help attenuate ischemia-reperfusion injury, a beneficial effect that may be related to the antioxidant capabilities of statins; however, this remains controversial. We performed this study to determine whether the HMG-CoA reductase inhibitor cerivastatin can prevent oxidative stress-induced injury in cultured human aortic endothelial cells (HAEC). The HAEC were subjected to oxidative stress in the absence and presence of increasing concentrations of cerivastatin (50 nM-1,000 nM). Oxidative stress was induced by increasing concentrations of hydrogen peroxide or endogenous superoxide anions generated by the inhibition of superoxide dismutase using diethylthiocarbamate (10 mM). Cell viability and mitochondrial activity were measured by mitochondria-dependent 3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) conversion. Cell morphology was also examined using light microscopy. Exposing HAEC to cerivastatin for 24 hours had no effect on cell viability using both cell morphology and MTT conversion: the HAEC incubated in 100 nM cerivastatin had 90% +/- 2.2% viability of the control. As expected, hydrogen peroxide produced a concentration-dependent decrease in cell viability. Varying concentrations of cerivastatin pretreatment for < or = 18 hours showed no protection of HAEC against hydrogen peroxide-induced injury. As a positive control, the prototype antioxidant N-acetyl-L-cysteine was cytoprotective even with the highest hydrogen peroxide concentration. Neither cerivastatin nor N-acetyl-L-cysteine protected HAEC against diethylthiocarbamate-induced oxidative injury at any concentration. In this study, cerivastatin did not protect cultured HAEC against oxidative stress induced by hydrogen peroxide or diethylthiocarbamate.

Aorta↗

PubMed2004

Mid-term pattern of survival, hemodynamic performance and rate of complications after medtronic freestyle versus homograft full aortic root replacement: results from a prospective randomized trial.

BACKGROUND AND AIM OF THE STUDY: The full homograft root replacement has been regarded as the 'gold standard' for aortic valve replacement (AVR). Xenograft full root AVR may offer similar theoretical advantages, but no prospective randomized trials to compare the two valve substitutes have been reported to date. METHODS: A total of 147 patients (mean age 66.2 years; range: 40-82 years) was randomized to undergo either Medtronic Freestyle (group F; n = 80) or homograft (group H; n = 67) root AVR. Coronary artery bypass grafting was associated with root AVR in 55 patients (37.4%). Follow up included routine clinical and echocardiographic assessments. RESULTS: Overall, there were seven early deaths (4.8%). The early mortality rate for isolated root AVR was 2.1% in group F (1/47) and 2.2% in group H (1/45) (p = NS). There were four late deaths in group F, and two in group H. Actuarial survival was 83+/-5% and 84+/-4% (p = NS) at five years, in groups F and H, respectively. No patient required reoperation on the aortic valve. Overall, there were eight thromboembolic events and six anticoagulant-related bleeding events; these were equally divided between the two groups. After a median follow up of 45 months, most patients in both groups were in NYHA class I, and the mean trans-aortic gradient was 6+/-1 mmHg in group F and 5+/-2 mmHg in group H (p = NS). Mild aortic regurgitation was recorded in 1/26 patients (4%) of group F, and in 1/16 (6%) of group H. CONCLUSION: The Medtronic Freestyle porcine xenograft appears to be a good alternative to homografts for full aortic root replacement, at least in the mid term.

Adult↗

PubMed2003

Off-Pump Coronary Artery Bypass (OPCAB) surgery reduces risk-stratified morbidity and mortality: a United Kingdom Multi-Center Comparative Analysis of Early Clinical Outcome.

OBJECTIVE: Off-Pump Coronary Artery Bypass (OPCAB) surgery is gaining more popularity worldwide. The aim of this United Kingdom (UK) multi-center study was to assess the early clinical outcome of the OPCAB technique and perform a risk-stratified comparison with the conventional Coronary Artery Bypass Grafting (CABG) using the Cardio-Pulmonary Bypass (CPB) technique. METHODS: Data were collected on 5,163 CPB patients from the database of the National Heart and Lung institute, Imperial College, University of London, and on 2,223 OPCAB patients from eight UK cardiac surgical centers, which run established OPCAB surgery programs. All patients had undergone primary isolated CABG for multi-vessel disease through a midline sternotomy approach, between January 1997 and April 2001. Postoperative morbidity and mortality were compared between the CPB and OPCAB patients after adjusting for case-mix. The mortality of the OPCAB patients was also compared, using risk stratification, to the mortality figures reported by the Society of Cardiothoracic Surgeons of Great Britain and Ireland (SCTS) based on 28,018 patients in the national database who were operated on between January 1996 and December 1999. RESULTS: Morbidity and mortality were significantly lower in the OPCAB patients compared with the CPB patients and the UK national database of CABG patients, over the same period of time, after adjusting for case-mix. CONCLUSIONS: This study demonstrates that risk stratified morbidity and mortality are significantly lower in OPCAB patients than CPB patients and patients in the UK national database.

Adult↗

PubMed2003

Kidney warming during transplantation.

The objective of the present study was to describe kidney temperature variations during transplantation and to identify the factors responsible for kidney warming. Kidney temperature was recorded steadily during transplantation. Kidney weight, body mass index (BMI), second warm ischemia time (t), and kidney temperature at the time of being placed in the recipient were analyzed so that we could evaluate their influence on kidney temperature and on kidney warming during transplantation. Kidney temperature at the time of removal from the container was 1.6 degrees C and 6. 3 degrees C when the kidney was placed in the recipient. Kidney temperature in the recipient depended on kidney temperature after serum washing (P<0.0001), but was independent of kidney preparation time (P=0.94). Then, kidney temperature (T) increased according to the logarithmic curve given in the following equation: T=7.2 ln(t)-0.6. Kidney temperature at the end of anastomosis was 26.7 degrees C. Kidney warming speed was 0.48 degrees/min and was dependent on the length of time of vascular anastomosis (P<0.0001). Kidney weight decreased the kidney warming speed (P=0.02). In conclusion, kidney warming increases slowly during ex vivo preparation. Kidney temperature stays below the damaging ischemic temperature of 18 degrees C. Because of its major impact on kidney warming, it is desirable that vascular anastomosis time be reduced, and, consequently, ex vivo kidney preparation needs to be meticulous.

Adolescent↗

PubMed2003

Is the female gender an independent predictor of adverse outcome after off-pump coronary artery bypass grafting?

BACKGROUND: The female gender is an independent predictor of adverse outcome after conventional coronary artery bypass grafting using cardiopulmonary bypass. The aim of this study is to assess the effect of the female gender on the outcome after off-pump coronary artery bypass (OPCAB) surgery. METHODS: This study is a retrospective review of 413 consecutive patients (181 women and 232 men) who underwent OPCAB between January 1999 and May 2001. Adverse outcomes were divided into minor adverse outcomes (MINAO), major adverse outcomes (MAJAO), and prolonged length of stay (PLOS) more than 7 days. MINAO included atrial fibrillation, respiratory complications except adult respiratory distress syndrome, and any wound infection except mediastinitis. MAJAO included stroke, myocardial infarction, renal failure, adult respiratory distress syndrome, mediastinitis, low cardiac output, mechanical ventilation more than 24 hours, intensive therapy unit stay more than 24 hours, gastrointestinal complications, cardiorespiratory arrest, and mortality within 30 days. Preoperative and intraoperative variables were evaluated as predictors of MINAO, MAJAO, and PLOS by univariate and multivariate analyses. RESULTS: The groups were matched for age and Parsonnet score-predicted mortality. However, the women had a higher incidence of chronic obstructive airway disease (p = 0.04), diabetes (p = 0.01), obesity (p = 0.000), peripheral vascular disease (p = 0.000), hypertension (p = 0.000), unstable angina (p = 0.005), history of previous failed nonsurgical intervention (p = 0.02), and nonelective operation (p = 0.000). There were a fewer number of grafts performed in the female group (2.8 vs 3.4, p = 0.000), with the circumflex territory being revascularised less frequently (p = 0.001). Univariate analysis identified the female gender to be a predictor of only MINAO (p = 0.001) and PLOS (p = 0.000). However, with multivariate analysis, female gender was not found to be an independent predictor of MINAO, MAJAO, or PLOS. CONCLUSIONS: In OPCAB, the female gender is not an independent predictor of MINAO, MAJAO, or PLOS.

Coronary Artery Bypass↗

PubMed2003

Is the use of cardiopulmonary bypass for multivessel coronary artery bypass surgery an independent predictor of operative mortality in patients with ischemic left ventricular dysfunction?

BACKGROUND: l Coronary artery bypass grafting for patients with ischemic left ventricular dysfunction (ILVD) remains superior to medical therapy in terms of long-term survival. Recently, off-pump coronary artery bypass surgery has been shown to be very promising in achieving functional improvements with favorable operative mortality in this challenging group of patients. The aim of this study was to assess the risk factors responsible for operative mortality in this group of patients. METHODS: The records of 305 consecutive ILVD patients, who underwent primary isolated coronary artery bypass grafting for multivessel disease at The National Heart and Lung Institute, Imperial College, University of London, between January 1999 and January 2002, were reviewed retrospectively. Patients were considered to have ILVD if they had a left ventricular ejection fraction of 0.30 or less on preoperative coronary angiography. One hundred six patients were operated on using the off-pump coronary artery bypass surgery technique, and 199 patients were operated on using the conventional coronary artery bypass grafting technique with cardiopulmonary bypass. RESU;TS: Seven (6.6%) patients died in the off-pump coronary artery bypass surgery group, whereas 28 (14.1%) patients died in the cardiopulmonary bypass group (p = 0.05). Univariate analysis of all the preoperative characteristics was performed to identify the potential predictors of mortality in the whole group of ILVD patients. Potential predictors of mortality included symptom status (stable/unstable), chronic obstructive airway disease, dyspnea grade III and IV on the New York Heart Association classification, intravenous nitrates, preoperative use of intraaortic balloon pump, ventricular tachycardia or ventricular fibrillation, body surface area less than 2, and cardiopulmonary bypass. Only ventricular tachycardia or ventricular fibrillation was proved to act as an independent predictor of operative mortality in this group of ILVD patients, with an odds ratio of 29.6 (95% confidence interval, 8.9 to 98). CONCLUSIONS: This study showed that using cardiopulmonary bypass for multivessel coronary artery bypass grafting in patients with ILVD was not proved to act as an independent predictor of operative mortality.

Aged↗

PubMed2003

Differential in vitro response of the human radial artery versus left internal thoracic artery to cerivastatin: implications to bypass grafting.

BACKGROUND: This study investigated acute (in vitro) and long-term (in vivo) effects of statins on the vascular function of human radial artery (RA) and left internal thoracic artery (LITA). METHODS: RA and LITA specimens were divided into vascular rings, which were incubated in the absence or presence of 10(-6) mol/L Cerivastatin for 2 or 24 hours. In terms of preoperative statin treatment, four groups included: group 1 [preop statin(-)/in vitro cerivastatin(-)]; group 2 [preop(-)/in vitro(+)]; group 3 [preop(+)/in vitro(-)]; and group 4 [preop(+)/in vitro(+)]. Endothelial function was assessed with acetylcholine (10(-9) to 10(-5) mol/L) following contraction by 3 x 10(-8) mol/L endothelin-1. RESULTS: Although endothelium-dependent vasodilatation was higher in RA (57.7% +/- 3.5%) than in LITA (46.5% +/- 3.8%, p = 0.046), there was no significant evidence that it depended on the preoperative use of statins or incubation period. In vitro incubation with cerivastatin significantly increased endothelium-dependent vasodilatation by 14.2% +/- 2.4% (p < 0.0001) independent of artery types (RA/LITA). There was no significant evidence that endothelium-dependent vasodilatation depended on the preoperative use of statins or incubation period. CONCLUSIONS: In vitro incubation with cerivastatin preserved endothelial function more effectively than preoperative use of statins. This could have implications to perioperative use of statins for patients undergoing coronary surgery.

Acetylcholine↗