Effects of exercise training after acute coronary syndromes in octogenarians - prospective 12-month evaluation.

OBJECTIVE: Aim: To demonstrate the impact of individual exercise training on the course of the disease, exercise tolerance and quality of life (QoL) in patients over 75 years after acute coronary syndrome (ACS). PATIENTS AND METHODS: Materials and methods: Study included octogenarians after ACS randomly assigned into two groups: a training group (ExT) subjected to individualized physical training and a control group (CG) with standard recommendations for activity. Patients underwent exercise tolerance test (ETT), 6-minute walk test (6-MWT), NHP and QoL questionnaires evaluation, lab tests, ECG, echocardiographic examination at the beginning and after 2, 6 and 12 months. RESULTS: Results: Study included 51 patients, mean age 80 years, 50% men, all patients completed the study. Initial physical capacity was comparable in both groups. After 2-month training the average ETT exercise time increased by 12.5% (p=0.0004), the load increased by 13% (p=0.0005) and the 6-MWT results improved by 8.3% (p=0.0114). Among CG these changes were not significant. But 6 and 12 months after training cessation 6-MWT results returned to the initial values (p=0.069, p=0.062 respecitvely). Average ETT exercise time and average load decreased significantly after 12 months (p=0.0009, p=0.0006). Level of pain was significantly lower at the end of the training in ExT group (p=0.007), but it returned to initial 12 months later (p=0.48). QoL deteriorated significantly in the ExT group 12 months after training cessation (p=0.04). CONCLUSION: Conclusions: Cardiac rehabilitation in octogenarians after ACS was safe and improved physical performance in a short period of time. Cessation of training resulted in a loss of achieved effects and deterioration of the QoL.

A Short Review of the Toxicity of Dentifrices-Zebrafish Model as a Useful Tool in Ecotoxicological Studies.

This review aims to summarize the literature data regarding the effects of different toothpaste compounds in the zebrafish model. Danio rerio provides an insight into the mechanisms of the ecotoxicity of chemicals as well as an assessment of their fate in the environment to determine long-term environmental impact. The regular use of adequate toothpaste with safe active ingredients possessing anti-bacterial, anti-inflammatory, anti-oxidant, and regenerative properties is one of the most effective strategies for oral healthcare. In addition to water, a typical toothpaste consists of a variety of components, among which three are of predominant importance, i.e., abrasive substances, fluoride, and detergents. These ingredients provide healthy teeth, but their environmental impact on living organisms are often not well-known. Each of them can influence a higher level of organization: subcellular, cellular, tissue, organ, individual, and population. Therefore, it is very important that the properties of a chemical are detected before it is released into the environment to minimize damage. An important part of a chemical risk assessment is the estimation of the ecotoxicity of a compound. The zebrafish model has unique advantages in environmental ecotoxicity research and has been used to study vertebrate developmental biology. Among others, the advantages of this model include its external, visually accessible development, which allows for providing many experimental manipulations. The zebrafish has a significant genetic similarity with other vertebrates. Nevertheless, translating findings from zebrafish studies to human risk assessment requires careful consideration of these differences.

Biomechanical parameters of the BP-enriched bone cement.

Bisphosphonates (BPs) are well-known substances with very efficient antiresorptive properties. Their beneficial actions are useful not only in achieving better bone mineral density but also in improving bone microarchitecture, strength and, consequently, its quality. Surgical cement, being a polymer composite, is required to be highly biocompatible and biotolerant. The goal of the presented study was to assess whether the enrichment of cement with pamidronate has changed its biomechanical properties. We compared the biomechanical parameters of clean bone cement and BP-enriched bone cement, which were both used formerly in our rat models. Biomechanical properties of BP-enriched bone cement are defined by two basic terms: stress and strain, which are caused by the influence of external force. In the investigatory process of the bone's biomechanical parameters, the compressive test and the three-point flexural tests were used. During the three-point flexural investigation, the sample was supported at both ends and loaded in the middle, resulting in a flexure. After a specific range of flexure, the sample was fractured. In obtained results, there were no significant differences in the values of the stress determined at the point of maximal load and the energy stored in the samples for proportional stress-strain limit (elastic region). There were also no significant differences in the density of the samples. The study shows that the enrichment of bisphosphonates causes yielding of the bone cement material. In the presented data, we conclude that use of pamidronate implanted in bone cement did not have a detrimental effect on its biomechanical properties. Therefore, the obtained results encouraged us to perform further in vivo experiments which assess the biomechanical properties of bones implanted with BP-enriched bone cement.

Association between influenza vaccination and cardiovascular outcomes in high-risk patients: a meta-analysis.

IMPORTANCE: Among nontraditional cardiovascular risk factors, recent influenzalike infection is associated with fatal and nonfatal atherothrombotic events. OBJECTIVES: To determine if influenza vaccination is associated with prevention of cardiovascular events. DATA SOURCES AND STUDY SELECTION: A systematic review and meta-analysis of MEDLINE (1946-August 2013), EMBASE (1947-August 2013), and the Cochrane Library Central Register of Controlled Trials (inception-August 2013) for randomized clinical trials (RCTs) comparing influenza vaccine vs placebo or control in patients at high risk of cardiovascular disease, reporting cardiovascular outcomes either as efficacy or safety events. DATA EXTRACTION AND SYNTHESIS: Two investigators extracted data independently on trial design, baseline characteristics, outcomes, and safety events from published manuscripts and unpublished supplemental data. High-quality studies were considered those that described an appropriate method of randomization, allocation concealment, blinding, and completeness of follow-up. MAIN OUTCOMES AND MEASURES: Random-effects Mantel-Haenszel risk ratios (RRs) and 95% CIs were derived for composite cardiovascular events, cardiovascular mortality, all-cause mortality, and individual cardiovascular events. Analyses were stratified by subgroups of patients with and without a history of acute coronary syndrome (ACS) within 1 year of randomization. RESULTS: Five published and 1 unpublished randomized clinical trials of 6735 patients (mean age, 67 years; 51.3% women; 36.2% with a cardiac history; mean follow-up time, 7.9 months) were included. Influenza vaccine was associated with a lower risk of composite cardiovascular events (2.9% vs 4.7%; RR, 0.64 [95% CI, 0.48-0.86], P = .003) in published trials. A treatment interaction was detected between patients with (RR, 0.45 [95% CI, 0.32-0.63]) and without (RR, 0.94 [95% CI, 0.55-1.61]) recent ACS (P for interaction = .02). Results were similar with the addition of unpublished data. CONCLUSIONS AND RELEVANCE: In a meta-analysis of RCTs, the use of influenza vaccine was associated with a lower risk of major adverse cardiovascular events. The greatest treatment effect was seen among the highest-risk patients with more active coronary disease. A large, adequately powered, multicenter trial is warranted to address these findings and assess individual cardiovascular end points.

Zebrafish and mouse models for anxiety evaluation - A comparative study with xanthotoxin as a model compound.

The ever-present trend for introducing new drugs of natural origin with anxiolytic properties meets healthcare needs of the population, whose almost 34 % struggles with anxiety-related disorders. At the same time, animal assays that could serve as fast and reliable models of anxiety-like behaviors are of great interest to scientists. Thus, the aim of the present study was to evaluate the utility of the zebrafish model for assessing the influence of natural compounds on anxiety in comparison with the well-known mouse model. Secondly, this study is also the first attempt to investigate the influence of a naturally occurring metabolite, i.e. xanthotoxin, on anxiety-related behaviors. The anxiety level in zebrafish was assessed by measuring thigmotaxis, a specific animal behavior to move closer to the boundaries of an open area and to avoid its center. In mice, the elevated plus maze test was chosen to study anxiety-related behaviors. Our results show that xanthotoxin exerted reversed U-shape effect on anxiety behaviors in both models. The similar pattern of xanthotoxin-induced anxiety-related behaviors in both animal models not only confirms the pharmacological properties of xanthotoxin but also proves the predictive power of the zebrafish model for behavioral research of natural compounds.

Baseline clinical characteristics and midterm prognosis of STE-ACS and NSTE-ACS patients with normal coronary arteries.

OBJECTIVE: We sought to compare clinical profiles and midterm prognosis of patients with normal coronary arteries presenting with ST-elevation ACS (STE-ACS) versus non-ST-elevation ACS (nSTE-ACS). BACKGROUND: There are limited data regarding ACS in patients with normal coronary arteries, and especially clinical differences between ST-ACS and nSTE-ACS patients have not been evaluated sufficiently. METHODS: The study group comprised 190 patients (mean age: 53.2 years, 63.1% males, 63.6% STE-ACS) presenting with ACS and normal coronary angiograms. The participants were evaluated in terms of 42 clinical variables. MACE [cardiac death (CD) and hospitalization for angina (HA)] were the study end points. RESULTS: STE-ACS in comparison to nSTE-ACS patients were younger (P < 0.01), were more frequently males (P < 0.01), had more often infection prior to ACS (P < 0.01), higher hsCRP on admission (P < 0.01), and greater infarct size, measured by maximal troponin I (P < 0.01). By multivariate analysis in this subgroup, predictors of outcome were hsCRP (P = 0.03) and raised troponin I (P = 0.02). nSTE-ACS in comparison to STE-ACS patients were more obese (BMI, P < 0.01), had higher LDL cholesterol (P < 0.01), fasting glucose (P = 0.03). LDL cholesterol (P = 0.02) and fasting glucose (P = 0.03) emerged as independent predictors of outcome in these patients. Mean follow-up period was 25.4 months. STE-ACS patients had twice fewer MACE rate than nSTE-ACS patients [(1-CD, 12-HA; 11%) vs (1-CD, 16-HA; 25%), respectively, log rank P < 0.01]. CONCLUSIONS: STE-ACS and nSTE-ACS patients with normal coronary arteriography have different clinical profiles. In nSTE-ACS patients more pronounced metabolic abnormalities were identified, while in STE-ACS patients inflammatory background was more significant.

Antibody response to influenza vaccine in coronary artery disease: a substudy of the FLUCAD study.

BACKGROUND: Influenza vaccination is recommended for patients with cardiovascular diseases. The main reason for the low vaccination rates in such patients is insufficient knowledge about vaccination efficacy, including immune response to the vaccine. The aim of this study was to assess humoral response to influenza vaccination in patients with coronary artery disease. MATERIAL/METHODS: This was a substudy of the randomized prospective double-blind placebo-controlled FLUCAD study on influenza vaccination in the secondary prevention of ischemic coronary events in patients with coronary artery disease. Patients received inactivated subunit vaccine (n=325) or placebo (n=333). Anti-hemagglutinin and anti-neuraminidase antibody levels to the vaccine strains as well as IgM and IgG levels against influenza A and B were measured before administration of vaccine/placebo and after 8-10 weeks in 78 vaccinated and 97 placebo patients. RESULTS: Post-vaccination antibody titers were significantly higher than before vaccination, with mean increases of 4.9- to 5.7-fold for anti-hemagglutinin and 3.5- to 4.2-fold for neuraminidase antibodies. Post-vaccination protection rates ranged from 56.4 to 60.3% and response rates from 62.8 to 68%. The percentage of patients with significant post-vaccination concentrations of IgG and IgM was higher than before vaccination and amounted to 100% and 88.1% in the case of IgG and 14.3% and 5.2% in the case of IgM in response to influenza A and B, respectively. CONCLUSIONS: At least 60% of the patients achieved high post-vaccination antibody levels sufficient to prevent influenza.

Sodium level on admission and in-hospital outcomes of STEMI patients treated with primary angioplasty: the ANIN Myocardial Infarction Registry.

BACKGROUND: Hyponatremia is a common electrolyte disorder reported to be a predictor of poor prognosis among hospitalized patients, but individuals with high levels also tend to have less favorable outcomes. This study investigated whether sodium level on admission is predictive of in-hospital outcome in patients with ST-elevation myocardial infarction (STEMI) treated with primary angioplasty. MATERIAL/METHODS: Included were 1858 patients admitted with STEMI for primary angioplasty. Sodium level was measured on admission and analyzed as hypo- versus normonatremia and by grouping patients into sodium quintiles. The relationships between sodium level and in-hospital mortality as well as the composite of death or heart failure were assessed. RESULTS: Ninety-six patients had hyponatremia on admission. The hypo- and normonatremic groups were comparable with respect to baseline characteristics and in-hospital management. Hyponatremics had higher rates of in-hospital mortality (13.5% vs. 3.8%, p<0.001) composite of death and heart failure (27.8% vs. 18.4%, p=0.022). After adjustment for covariates, hyponatremia independently correlated with in-hospital mortality (HR: 3.89, 95%CI: 1.59-9.56, p=0.003) and the combined endpoint (HR: 1.73, 95%CI: 1.01-2.99, p=0.047). Patients in the lowest and highest sodium quintiles were 3.27 (95%CI: 1.34-8.02, p=0.009) and 2.65 (95%CI: 1.07-6.60, p=0.036) times more likely to die during hospitalization than those in the 2nd quintile (best survival). In the adjusted model, only patients in the lowest quintile had significantly increased risk of in-hospital death (HR: 6.35, 95%CI: 1.83-21.72, p=0.004). CONCLUSIONS: Hyponatremia is a simple laboratory marker independently associated with increased risk of death in STEMI patients treated with primary angioplasty.

Influenza vaccination in secondary prevention from coronary ischaemic events in coronary artery disease: FLUCAD study.

AIMS: To evaluate the effect of influenza vaccination on the coronary events in patients with confirmed coronary artery disease (CAD). METHODS AND RESULTS: Randomized, double-blind, placebo controlled study. We included 658 optimally treated CAD patients; 477 men, mean age 59.9+/-10.3 years. Three hundred and twenty-five patients received the influenza vaccine, and 333 patients placebo. Median follow-up was 298 (interquartile range 263-317) days. Primary endpoint was the cardiovascular death. Its estimated 12-month cumulative event rate was 0.63% in the vaccine vs. 0.76% in controls (HR 1.06 95% CI: 0.15-7.56, P = 0.95). There were two secondary composite endpoints: (i) the MACE (cardiovascular death, myocardial infarction, coronary revascularization) tended to occur less frequently in the vaccine group vs. placebo with the event rate 3.00 and 5.87%, respectively (HR 0.54;95% CI: 0.24-1.21, P = 0.13). (ii) Coronary ischaemic event (MACE or hospitalization for myocardial ischaemia) estimated 12-month event rate was significantly lower in the vaccine group 6.02 vs. 9.97% in controls (HR 0.54; 95% CI: 0.29-0.99, P = 0.047). CONCLUSION: In optimally treated CAD patients influenza vaccination improves the clinical course of CAD and reduces the frequency of coronary ischaemic events. Large-scale studies are warranted to evaluate the effect of influenza vaccination on cardiovascular mortality. (ClinicalTrials.gov: NCT 00371098).

[Acetylsalicylic acid hypersensitivity in a patient with coronary artery disease and insulin-dependent diabetes mellitus]. / Nadwrazliwosc na kwas acetylosalicylowy u pacjentki z choroba wiencowa i cukrzyca insulinozalezna.

A case of a patient with unstable coronary artery disease, insulin-dependent diabetes mellitus and acetylsalicylic acid hypersensitivity is presented. Acetylsalicylic acid desensitisation and coronary angioplasty with stent implantation were successfully performed. The patient continues to receive antiplatelet therapy and has stable angina. No late hypersensitivity reactions were seen after a follow-up of 16 months.

Primary angioplasty in patients > or = 75 years old with ST-elevation myocardial infarction - one-year follow-up results.

BACKGROUND: Efficacy and safety of primary percutaneous coronary angioplasty (PCI) in elderly patients with acute ST-elevation myocardial infarction (STEMI) have not yet been definitely established because these patients were usually excluded from large randomised trials. AIM: To evaluate in-hospital and one-year outcome after primary PCI in elderly patients, and to assess clinical characteristics of this group. METHODS: The study population included 1061 consecutive STEMI patients, mean age 60.6+/-17 years, treated with primary PCI. Clinical characteristics and results of 127 patients aged > or = 75 years were compared to the younger group. RESULTS: Elderly patients were more frequently female (48.4 vs. 23.6%, p <0.005) and diabetics (22.2 vs. 12.1%, p <0.02) and more frequently had renal and/or left ventricular failure (22.3 vs. 9.1%, and 9.1 vs. 4.5%, p <0.005, respectively). In older patients less frequently stents were implanted and TIMI flow 3 was restored (65.1 vs. 78.8%, p <0.05 and 74.6 vs. 84.7%, p <0.03). In-hospital mortality in older versus younger patients was 11.8 vs. 3.0%, p <0.005. The incidence of in-hospital complications (stroke, major bleeding and reinfarction) was similar in both groups. The one-year mortality and MACE rates were higher in older patients (21.3 vs. 6.0% and 24.9 vs. 11.0%, p <0.0005). In multivariate analysis Killip class II-IV (OR 6.73; 95% CI 1.75-25.97, p=0.006) and heart rate (OR 1.04; 95% CI 1.01-1.07, p=0.03) were independent predictors of one-year mortality in patients aged > or = 75 years. CONCLUSIONS: Primary PCI in older STEMI patients is associated with a favourable in-hospital and one-year outcome, although inferior to that seen in younger patients. The in-hospital complication rate is similar in the elderly and in younger patients.

Cardioprotective effect of influenza and pneumococcal vaccination in patients with cardiovascular diseases.

Due to the wide interaction between the respiratory and the circulatory systems, influenza and pneumococcal vaccinations are recommended in the prevention and treatment of cardiovascular diseases. The review summarizes the results of recent studies and meta-analyses demonstrating that in this group of high-risk patients both vaccinations have potentially beneficial properties. However, in the era of Evidence Base Medicine, there is still a lack of randomized prospective clinical trials, especially those evaluating the effect of pneumococcal vaccination. As the burden of cardiovascular diseases represents various pathologies, it is important to point that the beneficial effect of vaccination is more pronounced in the atherosclerotic etiology, especially in patients after recent coronary events. This information contributes significantly to the appreciation of the role of the adaptive and innate immunity in atherosclerosis, which is now considered as immuno-inflammatory process driven by LDL-cholesterol intimal infiltration and macrophages activation. The mechanism of the cardioprotective effect of vaccination may not only be associated with the elimination of infections and their complications, but also related to the modification of the immuno-inflammatory model of atherosclerosis.

Medial patellofemoral ligament reconstruction in children: A comparative randomized short-term study of fascia lata allograft and gracilis tendon autograft reconstruction.

BACKGROUND: Many surgical procedures have been described to treat recurrent patellar dislocation, but none of these techniques has been successful in all patients. The goal of the study was to evaluate the results of medial patellofemoral ligament reconstruction in children. Two operative procedures were evaluated; a fascia lata allograft and an autologous gracilis graft. METHODS: Forty-four children (27 girls and 17 boys) between 13 and 17 years of age with unilateral recurrent patellar dislocation underwent medial patellofemoral ligament (MPFL) reconstruction. Patients were operated in two orthopedic centers. The 1st group contained 22 patients and surgery was performed using a fascia lata allograft. In the 2nd group of patients which also contained 22 children and autologous gracilis graft was used. The mean age of the patients was 14.9 years and the mean follow-up was 24 months. Preoperatively, all patients were evaluated clinically (Kujala score questionnaire) and radiologically. The same evaluation was used 18 to 30 months postoperatively to estimate the results of our treatment. RESULTS: In 1st group of children operated with cadaver allografts, the Kujala score significantly improved from 73.91 points preoperatively to 94.50 points postoperatively (P < .001). The average duration of operating procedure was 1 hour and 35 minutes. As shown by subjective symptoms, the results in 95% of patients were rated as good or very good. All children returned to full activity. Similar results were obtained in patients in 2nd group, where MPFL was reconstructed with ipsilateral gracilis tendon. Kujala score increased from 70.77 points preoperatively to 94.32 postoperatively (P < .001). Our results were estimated as good or very good in 93% of patients. All patients that were operated returned to full activity. However, median duration of operation was longer and lasted 1 hour and 55 minutes. CONCLUSIONS: Both techniques were effective in the short-term (18-30 months) in treatment of recurrent patellar dislocation. The use of cadaver allograft spares the hamstring muscles and reduces the time of surgery. Therefore, such study appears to be useful because it provides valuable information that would help to guide treatment of this condition in children. Level of evidence II-2.

Comparison of prognostic value of epicardial blood flow and early ST-segment resolution after primary coronary angioplasty. ANIN--Myocardial Infarction Registry.

BACKGROUND: TIMI scale is commonly used for angiographic assessment of reperfusion effectiveness and early risk stratification in patients treated with primary angioplasty for ST-elevation myocardial infarction (STEMI). Since ST-resolution analysis allows a noninvasive insight into the reperfusion status at the myocardial tissue level, it may be a better predictor of outcome after primary angioplasty. AIM: To compare the prognostic value of the reperfusion effectiveness evaluation based on either the epicardial blood flow assessment according to the TIMI scale, or ST-segment resolution analysis in patients treated with primary coronary angioplasty for STEMI. METHODS: 324 consecutive patients treated within 12 hours from the pain onset were studied. Based on the analysis of maximal ST-segment elevation/depression identified in a single ECG lead recorded after the procedure (maxSTE), patients were classified into groups of high versus medium/low risk. Independently, distinguished were groups with restored normal (TIMI 3) and abnormal (TIMI 0-2) final blood flow in infarct related artery. RESULTS: The 30-day and one-year mortality rates were higher in the high-risk maxSTE group (25% of all patients) than in the other patients (14.8% vs. 2.5%, p<0.001 and 18.5% vs. 5.4%, p<0.001 respectively). In subjects (82%) with restored TIMI grade 3 blood flow, mortality at one-month and one-year was lower than in the group with abnormal final blood flow (3.1% vs. 15.6%, p=0.001 and 6.2% vs. 18.8%, p=0.005). Comparison in multivariate analysis revealed that maxSTE stratification but not final TIMI grade assessment remained an independent predictor of both, 30-day and one-year mortality (high vs. medium/low-risk category; OR 5.3, 95% CI 1.6-16.7, p=0.005, and OR 3.3, 95% CI 1.4-7.8, p=0.007, respectively). Furthermore, maxSTE proved to stratify the risk of death even in subgroup of patients with restored normal blood flow (OR 6.2, 95% CI 1.4-27.8, p=0.016, and OR 3.0, 95% CI 1.1-8.7, p=0.039, respectively). CONCLUSIONS: Analysis of extent of maximal ST-segment elevation or depression identified in a single ECG lead after primary coronary angioplasty allows better prognosis of subsequent 30-day and one-year mortality than the assessment of final epicardial blood flow, stratifying risk of death even in a subgroup of patients with restored normal blood flow.

Total coronary occlusion of infarct-related arteries in patients with non-ST-elevation myocardial infarction undergoing percutaneous coronary revascularisation.

BACKGROUND: The prevalence and impact of total coronary occlusion of an infarct-related artery (IRA) on outcomes in patients with non-ST-elevation myocardial infarction (NSTEMI) remain unclear. AIM: We evaluated the clinical significance of total coronary occlusion in NSTEMI patients. METHODS: A total of 2767 patients with NSTEMI enrolled in the Polish Registry of Acute Coronary Syndromes, who underwent percutaneous coronary interventions, were analysed. The patients were divided into two groups according to preprocedural culprit vessel thrombolysis in myocardial infarction (TIMI) flows (TIMI flow 0 - total coronary occlusion [TO]: 728, 26.3% of the patients, and TIMI flow 1-3 - non-total occlusion [non-TO]: 2039, 73.7% of the patients). RESULTS: Patients with total occlusion were younger, were more often current smokers, and had lower incidence of hypertension and diabetes mellitus. The left circumflex artery (LCx) was the major IRA in the TO group (48.1%), whereas the left anterior descending artery (LAD) was more commonly the IRA in the non-TO group (38.8%). Multivariate analysis revealed that LCx as the culprit lesion (OR ± 95 CI 1.54 [1.26-1.89], p < 0.0001) was an independent predictor of TIMI flow 0 in IRA. In-hospital and one-month mortality occurred more frequently in the TO group (4.0% vs. 1.7%, p = 0.0005 and 5.5% vs. 3.5%, p = 0.0175, respectively), no differences in the 12-, 24-, or 36-month mortalities were observed between these groups. CONCLUSIONS: Only LCx as a culprit lesion was an independent predictor of total occlusion in IRAs. The NSTEMI patients with TO had higher in-hospital and one-month mortalities, but their long-term outcomes were similar to those of non-TO patients.

Endothelium-dependent acetylcholine-induced vasodilatory response of saphenous vein grafts.

INTRODUCTION: It has been suggested that endothelial dysfunction is critical to saphenous vein graft (SVG) occlusion. AIM: To evaluate in vivo endothelium-mediated vasoreactivity in angiographically non-stenotic SVG. METHODS: The group consisted of 31 patients (pts), aged 58.7+/-8.7 years, 54+/-38 months after coronary bypass surgery. In each patient one angiographically normal SVG was selected for the study. Endothelium-dependent vasoreactivity was investigated with acetylcholine (Ach) 50 microg intragraft infusion. Graft diameter changes were measured by quantitative computer angiography (QCA). RESULTS: In 17 (54.8%) pts there was a significant reduction in graft diameter following Ach infusion, from 3.8+/-0.7 to 3.2+/-0.7 mm (p=0.0001), whereas in 4 (12.9%) pts there were no diameter changes (3.2+/-0.7 mm). In the 10 remaining pts (32.3%) we found graft dilatation from 3.5+/-0.5 mm to 3.9+/-0.5 mm (p=0.0002). In multivariate linear regression analysis, SVG dilatation positively correlated with a low ratio of graft/artery diameter (p <0.002), high HDL-cholesterol level (p <0.001) and absence of hypertension (p <0.03), and negatively correlated with postoperative myocardial infarction (p <0.01). CONCLUSIONS: Endothelium-dependent vasodilatory response to Ach is present in one third of old SVG. Dilative response to Ach 50 is better preserved in SVG with smaller difference between graft/grafted artery diameters. Adequate matching of the graft/grafted artery diameters probably preserves the endothelium-dependent dilative response of the graft.