Search

Background: The effect of the cardioprotective Mediterranean diet on the development of cardiac abnormalities and prognosis of cardiac patients has rarely been investigated. Objective: We sought to evaluate the relation between the Mediterranean diet, the development of left ventricular systolic dysfunction (LVSD) at hospitalization, and the 2-y prognosis of patients who have had an acute coronary syndrome (ACS). Design: During 2006-2009, 1000 consecutive patients with ACS were enrolled; of these patients, 459 had LVSD (ejection fraction Results: The MedDietScore was associated with less likelihood of developing LVSD at hospitalization [odds ratio (OR) per 1/55 unit: 0.93; 95% CI: 0.88, 0.99; P = 0.04], less likelihood of remodeling (ie, ejection fraction Conclusions: Greater adherence to the Mediterranean diet seems to preserve left ventricular systolic function and is associated with better long-term prognosis of patients who have had an ACS. Am J Clin Nutr 2010;92:47-54. doi: 10.3945/ajcn.2009.28982.

Background: Choline and betaine are found in a variety of plant and animal foods and were recently shown to be associated with decreased homocysteine concentrations. Objective: The scope of this work was to investigate the associations between dietary choline and betaine consumption and various markers of low-grade systemic inflammation. Design: Under the context of a cross-sectional survey that enrolled 1514 men (18-87 y of age) and 1528 women ( 18-89 y of age) with no history of cardiovascular disease (the ATTICA Study), fasting blood samples were collected and inflammatory markers were measured. Dietary habits were evaluated with a validated foodfrequency questionnaire, and the intakes of choline and betaine were calculated from food-composition tables. Results: Compared with the lowest tertile of choline intake (310 mg/d had, on average, 22% lower concentrations of C-reactive protein (P < 0.05), 26% lower concentrations of interleukin-6 (P < 0.05), and 6% lower concentrations of tumor necrosis factor-[alpha] (P < 0.01). Similarly, participants who consumed >360 mg/d of betaine had, on average, 10% lower concentrations of homocysteine (P < 0.01), 19% lower concentrations of C-reactive protein (P < 0.1), and 12% lower concentrations of tumor necrosis factor-[alpha] (P < 0.05) than did those who consumed Conclusions: Our results support an association between choline and betaine intakes and the inflammation process in free-eating and apparently healthy adults. However, further studies are needed to confirm or refute our findings. KEY WORDS Inflammation, cardiovascular disease, risk factors, diet, choline, betaine

Background: Dietary habits have long been associated with many manifestations of cardiovascular disease. Objective: We sought to investigate whether a diet enriched with fish and n--3 fatty acid consumption are associated with changes in the potential duration of the electrical action, as represented by the QT duration on a resting electrocardiogram, in a population-based sample of Greek adults. Design: During 2001 and 2002, we randomly enrolled 1514 men (18-87 y old) and 1528 women (18-89 y old) stratified by age and sex distribution (in the 2001 Greek census) from the Attica area, Greece. We studied several demographic, anthropometric, lifestyle, dietary, and bioclinical factors of the participants. Dietary habits (including fish consumption) were evaluated by using a validated food-frequency questionnaire. All subjects underwent electrocardiography with a 12-lead surface, in which, along with several other indexes, QT duration was measured, and the heart rate--corrected QT (QTc) was calculated (corrected by using Bazett's rate). The tested hypothesis was evaluated through multiple linear regression analysis, after control for physical activity status, sex, age, medication intake, and several other potential confounders. Results: Compared with fish nonconsumers, those who consumed >300 g fish/wk had a mean 13.6% lower QTc (P < 0.01). These findings were confirmed after adjustment for age, sex, physical activity status, BMI, smoking habits, intake of nuts, and other confounders. Moreover, compared with fish nonconsumers, those who consumed [greater than or equal to] 300 g fish/wk had a 29.2% lower likelihood of having QTc intervals >0.45 s (P = 0.03). Conclusions: Long-term consumption of fish is associated with lower QTc interval in free-eating people without any evidence of cardiovascular disease. Thus, fish intake seems to provide antiarrhythmic protection at a population level. KEY WORDS Fish consumption, n--3 fatty acids, QTc interval, arrhythmia

A randomized, cross-sectional health and nutrition ATTICA survey conducted in the province of Attica, Greece, examines the relationship of physical activity and obesity with the glycemic control and insulin resistance. The study shows that in spite of physical activity being a very important factor for insulin sensitivity, an increase in the physical activity can reduce the common effects of obesity on the sensitivity of insulin.

Background: Homocystinemia is a metabolic abnormality associated with endothelial dysfunction and increased cardiovascular disease risk. The underlying mechanisms of these effects, however, are obscure. Objective: We examined the effect of asymmetrical dimethylarginine (ADMA) on endothelial dysfunction in methionine-induced and chronic homocystinemia and evaluated the regulatory role of oxidative stress and proinflammatory cytokines on the release of ADMA. Design: In this double-blind, placebo-controlled parallel group study, 30 subjects of both sexes (15 with homocystinemia and 15 healthy controls) underwent methionine loading, with simultaneous administration of a combination of vitamin C (2g) plus [alpha]-tocopherol (800 IU) or placebo. Endothelial function in forearm resistance vessels and concentrations of ADMA, oxidized LDL, and proinflammatory cytokines were determined at baseline and 4 h after methionine loading. Results: Both chronic and methionine-induced homocystinemia were associated with increased oxidized LDL (P < 0.01), higher expression of the proinflammatory cytokine interleukin 6 (P < 0.05), and endothelial dysfunction (P < 0.01). Although ADMA rapidly increased in acute homocystinemia (P < 0.01) and was correlated with forearm hyperemic response at 4 h after methionine loading (r = -0.722, P = 0.0001), it was not higher in subjects with high versus low fasting homocysteine. High-dose antioxidant treatment prevented methionine-induced elevation of oxidized LDL and interleukin 6 but failed to prevent the increase in ADMA or endothelial dysfunction. Conclusions: Both chronic and methionine-induced homocystinemia are characterized by increased oxidative stress and proinflammatory cytokines, which may contribute to the development of endothelial dysfunction. However, the ADMA pathway is activated only in acute homocystinemia by mechanisms not mediated by oxidized LDL or proinflammatory stimuli. KEY WORDS Vitamins, endothelium, asymmetrical dimethylarginine, ADMA, atherosclerosis, homocysteine, inflammation

We examine a mechanism by which bundling may inefficiently deter entry into the market. The model considers an incumbent monopolist in two complementary components that faces a series of entry attempts by rivals. It is shown that the incumbent can practice bundling to buttress its monopoly position by keeping specialist innovators out of the market. Bundling prevents specialist rivals from coordinating in the dynamic entry process, reducing the probability of an eventual displacement of the incumbent. The specialization decisions of rivals are also distorted. Bundling may lead to lower customer and total economic welfare.

Background: Greater adherence to the Mediterranean diet has been associated with a lower incidence of cardiovascular disease and cancer. Objective: We studied the effect of the Mediterranean diet on total antioxidant capacity (TAC) in 3042 participants who had no clinical evidence of cardiovascular disease. Design: During 2001-2002, a random sample of 1514 men and 1528 women aged 18-89 y from the Attica area of Greece was selected. TAC was measured with an immune-diagnostic assay. Food consumption was evaluated with a validated food-frequency questionnaire, and adherence to the Mediterranean diet was assessed on the basis of a diet score that incorporated the inherent characteristics of this diet. Results: TAC was positively correlated with diet score. The participants in the highest tertile of the diet score had, on average, 11% higher TAC levels than did the participants in the lowest tertile, even after adjustment for relevant confounders (P < 0.01). On the other hand, the participants in the highest tertile of the diet score had, on average, 19% lower oxidized LDL-cholesterol concentrations than did the participants in the lowest tertile (P < 0.01). An additional analysis showed that TAC was positively correlated with the consumption of olive oil ([rho] = 0.54. P = 0.002) and of fruit and vegetables ([rho] = 0.34 and [rho] = 0.31, respectively; P < 0.001 for both), whereas it was inversely associated with the consumption of red meat ([rho] = -0.35, P = 0.02). Conclusion: Greater adherence to the Mediterranean diet is associated with elevated TAC levels and low oxidized LDL-cholesterol concentrations, which may explain the beneficial role of this diet on the cardiovascular system. KEY WORDS Mediterranean diet, antioxidant capacity, oxidized LDL cholesterol, cardiovascular disease

OBJECTIVE--Patients with coronary artery disease (CAD) and diabetes show increased inflammatory activation. Thermography detects local inflammatory involvement as heat generation. The aim of this study was to investigate whether patients [...]

Background: The effect of coffee consumption on the cardiovascular system is still an unresolved issue. Aortic stiffness and wave reflections are important prognosticators of cardiovascular disease risk. We have shown that caffeine acutely increases aortic stiffness and wave reflections. Objective: The objective was to investigate the effect of chronic coffee consumption on aortic stiffness and wave reflections. Design: This was a cross-sectional study of 228 healthy subjects: 141 men ([bar.x] SD: 41 [+ or -] 8 y old) and 87 women (41 [+ or -] 9y old). Aortic stiffness was evaluated with carotid-femoral pulse wave velocity (PWV). Wave reflections were evaluated with augmentation index (AIx) and augmented pressure (AP) of the aortic pressure waveform with the use of high-fidelity pulse wave analysis. Coffee consumption was ascertained over 1 y with a food-frequency questionnaire. Results: A linear relation between coffee consumption and PWV, AIx, and AP was observed (P for trend < 0.05). Compared with the nonconsumption group, PWV was on average 13% higher, AIx was 2-fold higher, and AP was 2.4-fold higher (P < 0.01 for all) in the high-consumption group (>450 mL/d). The findings remained significant after control for confounders such as age, sex, smoking habits, body mass index, total and LDL cholesterol, triacylglycerols, blood glucose, mean blood pressure, and heart rate. The linear relation (P for trend < 0.05) observed between coffee consumption and arterial pressures was largely explained when the covariates were entered in the model. Conclusions: Chronic coffee consumption exerts a detrimental effect on aortic stiffness and wave reflections, which may increase the risk of cardiovascular disease. KEY WORDS Aorta, caffeine, coffee, stiffness, wave reflections

Background: The effect of coffee consumption on the cardiovascular system is conflicting. Inflammation is important to the development of cardiovascular disease (CVD), and several dietary factors are thought to exert significant effects on inflammation and thus on the risk of CVD. Objective: We aimed to investigate the associations between coffee consumption and inflammatory markers. Design: The cross-sectional survey enrolled 1514 men ([bar.x] [+ or -] SD age: 46 [+ or -] 13 y; range: 18-87 y) and 1528 women (aged 45 [+ or -] 13 y; range: 18-89 y). Five percent of men and 3% of women were excluded for history of CVD. Fasting blood samples were collected. Dietary habits (including consumption of various types of coffee) were evaluated by using a validated food-frequency questionnaire. Results: Compared with coffee nondrinkers, men who consumed >200 mL coffee/d had 50% higher interleukin 6 (IL-6), 30% higher C-reactive protein (CRP), 12% higher serum amyloid-A (SAA), and 28% higher tumor necrosis factor a (TNF-[alpha]) concentrations and 3% higher white blood cell (WBC) counts (all: P < 0.05). Women who consumed >200 mL coffee/d had 54% higher IL-6, 38% higher CRP, 28% higher SAA, and 28% higher TNF-[alpha] concentrations and 4% higher WBC counts (all: P < 0.05) than did coffee nondrinkers. The findings were significant even after control for the interactions between coffee consumption and age, sex, smoking, body mass index, physical activity status, and other covariates. Conclusions: A relation exists between moderate-to-high coffee consumption and increased inflammation process. This relation could explain, in part, the effect of increased coffee intake on the cardiovascular system. KEY WORDS Inflammation, cardiovascular disease, risk factors, coffee

Background: Dietary and genetic factors may influence the effect of raised homocysteine concentrations on coronary artery disease risk. Objective: We evaluated the effect of the interaction between adoption of a Mediterranean diet and the methylenetetrahydrofolate reductase gene (MTHFR) 677C[right arrow]T mutation on homocysteine concentrations in healthy adults participating in the ATTICA study. Design: We studied demographic, lifestyle, clinical, biochemical, and genetic information from 322 men ([bar.x] [+ or -] SD age: 46 [+ or -] 13 y) and 252 women (45 [+ or -] 14 y) who had no clinical evidence of cardiovascular or any other chronic disease. We also measured total plasma homocysteine concentrations, the distribution of the MTHFR genotype, and adherence to a Mediterranean diet. Results: The distribution of MTHFR genotypes was as follows: homozygous normal (CC), 41%; heterozygous (CT), 48%; and homozygous mutant (TT), 11%. Homocysteine concentrations were higher in persons with the TT genotype than in those with the CC and CT genotypes ([bar.x] [+ or -] SD: 15.8 [+ or -] 9 compared with 11.3 [+ or -] 8 and 10.8 [+ or -] 9 [micro]mol/L, respectively; P < 0.001). The Mediterranean diet score was not significantly associated with homocysteine concentrations (P = 0.89). However, after control for potential confounders, the stratified analysis showed that adherence to a Mediterranean diet was associated with reduced homocysteine concentrations in persons with the TT and CT genotypes ([beta] = -0.21, P = 0.002, and [beta] = -0.14, P = 0.025, respectively) but not in those with the CC genotype ([beta] = -0.03, P = 0.38). Conclusion: The observed association of an MTHFR 677C[right arrow]T gene-diet interaction on homocysteine concentrations may provide a pathophysiologic explanation for how a Mediterranean diet may influence coronary risk in persons with raised homocysteine concentrations. KEY WORDS Homocysteine, methylenetetrahydrofolate reductase, MTHFR genotype, cardiovascular disease, Mediterranean diet

OBJECTIVE--To examine the effect of vitamin C on forearm vasodilatory response to reactive hyperemia and on plasma level of plasminogen activator inhibitor (PAl-1), von Wil1ebrand factor (vWF), tissue plasminogen activator [...]

Byline: Christodoulos Stefanadis, John Dernellis, Eleftherios Tsiamis, Costas Stratos, Ioannis Kallikazaros, Pavlos Toutouzas Abstract: Objective: The physiologic basis for the hemodynamic and clinical improvement achieved by the use of intra-aortic balloon pumping in patients with cardiogenic shock has not been clarified in all its aspects. This study evaluated the possible contribution of pump-induced alterations of aortic mechanics to the overall benefit gained by the implementation of this therapeutic modality in patients with acute heart failure of ischemic origin. Methods: The aortic pressure-diameter relation was obtained by use of an intravascular catheter for aortic diameter measurements developed in our institution and previously validated, simultaneously with a catheter-tip micromanometer for aortic pressure measurements at the same aortic level. Aortic function indices were compared before and during intra-aortic balloon pumping in 12 patients with cardiogenic shock. Results: Intra-aortic balloon pumping increased cardiac index and aortic distensibility by 24% and 30%, respectively, and reduced myocardial oxygen demand by 31% (P < .001 for all alterations). Energy loss caused by aortic wall viscosity increased by 207% (P < .001). The aortic diameter augmentation index increased by 68% (P < .001); the aortic pressure augmentation index decreased by 117% (P < .001). Linear regression analysis showed that cardiac index and myocardial oxygen demand were related with the aortic stiffness constant both before and during intra-aortic balloon pumping. Conclusions: During intra-aortic balloon pumping, aortic distensibility was improved, and wave reflection from the arterial periphery was reduced. The relationship between cardiac index and myocardial oxygen demand and aortic stiffness suggests that improvement of the elastic properties of the aorta was an important mechanism by which intra-aortic balloon pumping improved circulatory function. (J Thorac Cardiovasc Surg 1998;116:1052-9) Article History: Received 8 May 1998; Accepted 28 July 1998 Article Note: (footnote) [star] From the Hippokration Hospital, Department of Cardiology, University of Athens, Greece., [star][star] Supported in part by a grant from the Helenic Heart Foundation., a Address for reprints: Christodoulos Stefanadis, MD, FESC, FACC, 9 Tepeleniou Str, 15452 Paleo Psychico, Athens, Greece., aa 12/1/93475

I examine a mechanism by which exclusive supply contracts may inefficiently deter entry into the market. In the model, the incumbent supplier selectively offers contracts only to some buyers and convinces them to consent by guaranteeing them low prices. The contracts strengthen the monopoly position of the incumbent supplier and allow it to extract rents from remaining buyers that were not offered contracts. Aside from the favorable contract terms, buyers have another reason to consent to the exclusivity scheme: the latter raises the input costs of rival buyers that were not offered contracts. The model has potential applications to the recent Microsoft antitrust case (1994). I define exclusive supply contract as an agreement under which an upstream firm becomes the exclusive supplier of a downstream firm; the downstream firm is prohibited from buying from other suppliers.

Background: The aorta acts as both a conduit and an elastic buffering chamber that modulates left ventricular function and coronary blood flow. Previous studies have shown that active smoking has unfavorable effects on aortic elasticity. Objective: To study the association between passive smoking and the elastic properties of the human aorta. Design: Comparison of nonsmokers during passive smoking studies and smokers during active smoking or sham smoking studies. Setting: Academic medical center. Participants: 16 male nonsmokers were assigned to passive smoking studies, and 32 current, long-term, male smokers were randomly assigned to either active smoking (16 patients) or sham smoking (16 patients) studies. intervention: All participants underwent diagnostic catheterization. in the passive smoking group, environmental tobacco smoke was vented into an exposure chamber for 5 minutes (mean carbon monoxide level, 30 parts per million). Each participant in the active smoking group smoked one filtered cigarette (1.0 mg of nicotine) under standardized conditions within 5 minutes; each participant in the sham smoking group performed a similar pattern of inhalation with one unlit cigarette. Measurements: Aortic elastic properties were studied by measuring the aortic pressure-diameter relation before and for 20 minutes after passive, active, or sham smoking. instantaneous diameter of the thoracic aorta was measured with a high-fidelity ultrasonic dimension catheter. instantaneous aortic pressure and diameter were measured at the same site. Results: Both passive and active smoking were associated with changes in the aortic pressure-diameter relation (change in mean distensibility in the passive smoking group, from 2.02 to 1.59 x [10.sup.-6] [cm.sup.2] [multiplied by] [dyne.sup.-1] [for comparisons of time course between passive and sham smoking groups, P [is less than]0.001; change in mean distensibility in the active smoking group, from 2.08 to 1.51 x [10.sup.-6] [cm.sup.2] [dyne.sup.-1] [for comparisons of time course between active and sham smoking groups, P [is less than]0.001 ]). These changes represent decreases of 21% and 27%, respectively. No changes in aortic elasticity were seen in the sham smoking group. Conclusions: Both passive and active smoking are associated with an acute deterioration in the elastic properties of the aorta. This association between exposure to tobacco smoke and aortic elasticity indicates that aortic function deteriorates during passive or active smoking., Both active and passive smoking appear to adversely affect the aorta, which is the major artery that distributes blood from the heart to the rest of the body. The aorta must remain elastic in order to absorb the blood from each heart contraction. Researchers used ultrasound to measure the diameter and pressure inside the aorta in 16 male non-smokers exposed to passive smoke and 32 male smokers while they smoked. The elasticity of the aorta dropped 21% in non-smokers exposed to passive smoke and 27% in smokers while they smoked. This could be one means by which smoking causes cardiovascular disease.

To study the effect of nifedipine on aortic distensibility in patients with coronary artery disease, ascending aorta distensibility was measured before and 10 min after 10 mg of nifedipine was [...]

PURPOSE- The purpose of the present investigation was to study the distensibility of the ascending aorta in patients with arterial hypertension and normal subjects before and after administration of a calcium antagonist, nifedipine. PATIENTS AND METHODS: The distensibility of the ascending aorta was measured before and after nifedipine administration in 22 male hypertensive patients and 12 age-matched male normotensive subjects. Aortic distensibility was calculated as a function of changes in aortic diameter and pulse pressure, using the formula: 2 x (pulsatile change in aortic diameter)/[(diastolic aortic diameter) x (aortic pulse pressure)]. Aortic diameters were measured by echocardiography and aortic pressures were obtained by catheterization of the ascending aorta. RESULTS: In the basal state, the distensibility of the ascending aorta and aortic strain were lower in hypertensive patients than in normotensive subjects (p

A new technique was developed for percutaneous mitral valve balloon valvuloplasty, using a retrograde approach to the left atrium via the left ventricle. A newly designed externally steerable guiding catheter is used for the introduction of 1 or 2 guidewires to the left atrium and the balloon catheters are advanced along these guidewires into the mitral orifice. The technique was used successfully in 10 adult patients with rheumatic mitral stenosis. After the procedure there was a significant reduction in mitral valve pressure gradient and an increase in the mitral valve area in all cases. There were no serious complications during or after the procedure. This technique should prove to be a useful nonsurgical treatment for mitral stenosis and could provide an alternative to the transseptal method. (Am J Cardiol 1990;65:650-654), Stenosis (constriction or narrowing) of the heart's mitral valve is a frequent consequence of rheumatic fever. It is often treated by percutaneous balloon valvuloplasty, in which a balloon catheter is threaded from a leg artery into the aorta, and then into the heart to widen the heart valve with the balloon. These procedures usually get to the heart valve by puncturing the atrial septum, one of the inner heart walls. A newly designed catheter is now able to be threaded into the heart, and then steered through the heart chambers, without the need for septum puncture. The procedure was successfully utilized in 10 patients with moderate to severe mitral stenosis. There were minimal complications, and mitral valve function improved in all cases. The new technique may be an attractive alternative to the transseptal method. (Consumer Summary produced by Reliance Medical Information, Inc.)

9781466587144 Biomarkers in cardiovascular diseases. Ed. by Dimitris Tousoulis and Christodoulos Stefanadis. CRC Press 2013 442 pages $149.95 Hardcover RC670 Tousoulis and Stefanadis (cardiology, Athens U., Greece) compile 16 chapters [...]

Byline: Costas P. Tsioufis, Christodoulos I. Stefanadis, Eleftherios G. Tsiamis, Ioannis E. Kallikazaros, Pavlos K. Toutouzas Author Affiliation: Department of Cardiology, University of Athens, Hippokration Hospital, Athens, Greece Article History: Received 12 July 1999; Accepted 11 August 1999 Article Note: (footnote) [star] Address for reprints: Costas Tsioufis, MD, 4, Athanasiou Diakou St, 15127 Melissia, Greece., [star][star] J Thorac Cardiovasc Surg 1999;118:1120-2, a 0022-5223/99 $8.00 + 0 12/54/102082