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Dive into the research topics where Ignatios Ikonomidis is active.

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Featured researches published by Ignatios Ikonomidis.


Circulation | 2008

Inhibition of Interleukin-1 by Anakinra Improves Vascular and Left Ventricular Function in Patients With Rheumatoid Arthritis

Ignatios Ikonomidis; John Lekakis; Maria Nikolaou; Ioannis Paraskevaidis; Ioanna Andreadou; Theophania Kaplanoglou; Pelagia Katsimbri; Grigorios Skarantavos; Panayiotis N. Soucacos; Dimitrios Th. Kremastinos

Background— Interleukin-1 increases nitrooxidative stress. We investigated the effects of a human recombinant interleukin-1a receptor antagonist (anakinra) on nitrooxidative stress and vascular and left ventricular function. Methods and Results— In an acute, double-blind trial, 23 patients with rheumatoid arthritis were randomized to receive a single injection of anakinra (150 mg SC) or placebo and, after 48 hours, the alternative treatment. At baseline and 3 hours after the injection, we assessed (1) coronary flow reserve, aortic distensibility, systolic and diastolic (Em) velocity of the mitral annulus, and E to Em ratio (E/Em) using echocardiography; (2) flow-mediated, endothelium-dependent dilation of the brachial artery; and (3) malondialdehyde, nitrotyrosine, interleukin-6, endothelin-1, and C-reactive protein. In a chronic, nonrandomized trial, 23 patients received anakinra and 19 received prednisolone for 30 days, after which all indices were reassessed. Compared with baseline, there was a greater reduction in malondialdehyde, nitrotyrosine, interleukin-6, and endothelin-1 and a greater increase in flow-mediated dilation, coronary flow reserve, aortic distensibility, systolic velocity of mitral annulus, and E/Em after anakinra than after placebo (malondialdehyde −25% versus 9%; nitrotyrosine −38% versus −11%; interleukin-6 −29% versus 0.9%; endothelin-1 −36% versus −11%; flow-mediated dilation 45% versus −9%; coronary flow reserve 29% versus 4%; and aortic distensibility 45% versus 2%; P<0.05 for all comparisons). After 30 days of treatment, the improvement in biomarkers and in vascular and left ventricular function was greater in the anakinra group than in the prednisolone group (P<0.05). Conclusions— Interleukin-1 inhibition improves vascular and left ventricular function and is associated with reduction of nitrooxidative stress and endothelin.


Hypertension | 2005

Time Rate of Blood Pressure Variation Is Associated With Increased Common Carotid Artery Intima-Media Thickness

N. Zakopoulos; Georgios Tsivgoulis; Gerassimos D. Barlas; Christos Papamichael; Konstantinos Spengos; Efstathios Manios; Ignatios Ikonomidis; Vassilios Kotsis; Ioanna Spiliopoulou; Konstantinos Vemmos; Myron Mavrikakis; Spyridon D. Moulopoulos

The extent of target-organ damage has been positively associated with the magnitude of blood pressure (BP) variability in essential hypertension. However, the clinical implications of the rate of BP changes have never been investigated. We evaluated the association between the rate of systolic BP (SBP) variation derived from ambulatory BP monitoring (ABPM) data analysis and the extent of common carotid artery (CCA) intima-media thickness (IMT) in normotensive (n=280) and in uncomplicated hypertensive subjects (n=234). The 24-hour rate of SBP variation was significantly (P<0.001) higher in hypertensive (0.608 mm Hg/min; 95% confidence interval [CI], 0.595 to 0.622) than in normotensive individuals (0.567 mm Hg/min; 95% CI, 0.555 to 0.578), even after adjusting for baseline characteristics, day–night BP changes, 24-hour heart rate (HR), SBP, and HR variability. In the entire group of patients, multiple linear regression models revealed independent determinants of CCA-IMT in the following rank order: age (P<0.001), 24-hour rate of SBP variation (P<0.001), male gender (P=0.004), cholesterol (P=0.009), and smoking (P=0.014). A 0.1 mm Hg/min increase in the 24-hour rate of SBP variation was associated to an increment of 0.029 mm (95% CI, 0.018 to 0.040) in CCA-IMT independent of BP and HR levels, BP and HR variability, and dipping status. The rate of SBP variation during the morning BP surge correlated independently (P<0.001) to larger CCA-IMT values after adjustment for baseline characteristics and other ABPM parameters. Thus, the rate of BP fluctuations is greater in hypertensive patients and correlates to increased CCA-IMT. This finding indicates that steeper BP variations may produce a greater stress on the vessel wall and consequently result in medial hypertrophy of the large arteries.


American Heart Journal | 1999

Natural history of early aortic paraprosthetic regurgitation : A five-year follow-up

Loukianos S. Rallidis; Ioannis Moyssakis; Ignatios Ikonomidis; Petros Nihoyannopoulos

OBJECTIVES To assess the incidence and natural course of paravalvular leaks detected early after aortic valve replacement. BACKGROUND Although the use of echocardiography has simplified the postoperative assessment of patients with aortic valve replacement, there are no data regarding the natural history of early detected paravalvular aortic leaks. METHODS Eighty-four consecutive patients with aortic valve replacement were prospectively followed clinically every 6 months and by echocardiography early (11 +/- 7 days), at midterm (27 +/- 3 months), and late (63 +/- 4 months) after aortic valve replacement. The competence of artificial valves was assessed by Doppler color flow mapping. RESULTS Paraprosthetic leaks were detected in 40 (47.6%) aortic prostheses during the early study; the majority (90%) were small. All leaks remained unchanged during the follow-up period. Left ventricular dimensions and function did not differ between patients with or without paravalvular leak during the follow-up. Left ventricular fractional shortening, however, increased during the intermediate study in both subgroups, indicating improved left ventricular function overall. Three patients had severe paravalvular regurgitation suddenly develop from late infective endocarditis, and 1 patient had a degenerative tissue valve failure 4 years after implantation. CONCLUSIONS Paraprosthetic aortic leaks detected early after surgery, in the absence of valve infection, are common, are usually small, and have a benign course. However, the development of new, usually severe, regurgitation should raise the suspicion of prosthetic valve endocarditis or bioprosthetic valve failure.


European Journal of Preventive Cardiology | 2011

Methods for evaluating endothelial function: a position statement from the European Society of Cardiology Working Group on Peripheral Circulation

John Lekakis; Pierre Abraham; Alberto Balbarini; Andrew D. Blann; Chantal M. Boulanger; John R. Cockcroft; Francesco Cosentino; John E. Deanfield; Augusto Gallino; Ignatios Ikonomidis; Dimitrios Th. Kremastinos; Ulf Landmesser; Athanase D. Protogerou; Christodoulos Stefanadis; Dimitris Tousoulis; Giuseppe Vassalli; Hans Vink; Nikos Werner; Ian B. Wilkinson; Charalambos Vlachopoulos

The endothelium holds a pivotal role in cardiovascular health and disease. Assessment of its function was until recently limited to experimental designs due to its location. The advent of novel techniques has facilitated testing on a more detailed basis, with focus on distinct pathways. This review presents available in-vivo and ex-vivo methods for evaluating endothelial function with special focus on more recent ones. The diagnostic modalities covered include assessment of epicardial and microvascular coronary endothelial function, local vasodilation by venous occlusion plethysmography and flow-mediated dilatation, arterial pulse wave analysis and pulse amplitude tonometry, microvascular blood flow by laser Doppler flowmetry, biochemical markers and bioassays, measurement of endothelial-derived microparticles and progenitor cells, and glycocalyx measurements. Insights and practical information on the theoretical basis, methodological aspects, and clinical application in various disease states are discussed. The ability of these methods to detect endothelial dysfunction before overt cardiovascular disease manifests make them attractive clinical tools for prevention and rehabilitation.


Journal of Hypertension | 2007

Weight loss after bariatric surgery improves aortic elastic properties and left ventricular function in individuals with morbid obesity: a 3-year follow-up study.

Ignatios Ikonomidis; Andreas Mazarakis; Costas G. Papadopoulos; Nikolaos Patsouras; Fotis Kalfarentzos; John Lekakis; Dimitrios Th. Kremastinos; Dimitrios Alexopoulos

Objective To investigate whether weight loss after bariatric surgery (gastric bypass) is associated with changes in aortic function (an important determinant of left ventricular function) and in left ventricular function, in morbidly obese individuals 3 and 36 months after surgery. Methods We used echocardiography to evaluate 60 obese individuals [body mass index (BMI) > 40 kg/m2] who underwent surgery and 20 obese individuals who neither underwent surgery nor lost weight, at baseline and at 3 and 36 months of follow-up, and 40 lean individuals (BMI < 25 kg/m2) of similar age, sex and risk factors, at baseline. We measured aortic strain, distensibility, stiffness index, pressure–strain modulus and Doppler indices of left ventricular diastolic dysfunction (ratio of peak early to peak atrial flow velocities, isovolumic relaxation time and deceleration time). Results Baseline aortic function and Doppler diastolic indices were impaired in obese individuals compared with those who were lean (P < 0.05). During 3 and 36 months of follow-up, BMI and left ventricular diastolic diameter, volume, mass and wall thickness were reduced, and indices of aortic function and left ventricular diastolic function were normalized, in obese individuals after surgery [aortic distensibility (cm2 × dyn−1 × 10−6): 1.9 before surgery, 3.4 at 3 months after surgery and 4.3 at 3 years after surgery, compared with 3.36 in lean controls; P < 0.01], but not in those who did not lose weight. The reduction in BMI after surgery was related to the concomitant improvement in indices of aortic function (P < 0.01) and isovolumic relaxation time (P < 0.05) after adjustment for age, sex and concomitant reduction in blood pressure, lipids and glucose concentrations. Conclusion Weight reduction after bariatric surgery normalizes aortic function, reduces left ventricular hypertrophy and, thus, improves left ventricular diastolic function in morbidly obese individuals over a 3-year period of follow-up.


American Journal of Hypertension | 2008

Incremental Value of Pulse Wave Velocity in the Determination of Coronary Microcirculatory Dysfunction in Never-treated Patients With Essential Hypertension

Ignatios Ikonomidis; John Lekakis; Costas G. Papadopoulos; Helen Triantafyllidi; Ioannis Paraskevaidis; Georgia Georgoula; Stavros Tzortzis; Ioanna Revela; Dimitrios Th. Kremastinos

BACKGROUND Coronary microcirculation is disturbed in essential hypertension. We investigated whether arterial stiffness determines coronary flow reserve (CFR) in hypertensive patients. METHODS We examined 100 never-treated hypertensives and 20 healthy controls. We measured (i) carotid-to-femoral pulse wave velocity (PWV); (ii) Systolic (V (s)) and diastolic (V (d)) coronary flow velocity, time integral (V (TI)-V (d)) of diastolic velocity and CFR after adenosine by transthoracic echocardiography; (iii) ratio of E wave from mitral inflow to Em of mitral annulus, as an index of left ventricular (LV) diastolic pressures using tissue Doppler; (iv) carotid intima-media thickness (IMT), as an index of vascular damage; and (v) 24-h blood pressure parameters using ambulatory blood pressure monitoring. RESULTS Patients had abnormal PWV, IMT, E/Em, resting V (d)/V (s), and CFR than controls (P < 0.05). In hypertensives, PWV was related to abnormal IMT and E/Em which in turn were related to reduced CFR (P < 0.05). PWV and E/Em were independent determinants of CFR and V (d)/V (s) (P < 0.05) in hypertensives. When added to a model including age, sex, smoking, LV mass (LVM), heart rate, 24-h systolic blood pressure (SBP), and E/Em, PWV had an incremental value in the determination of CFR (r (2) change from 0.25 to 0.46, P < 0.01). PWV >10.7 m/s predicted a CFR <2 with 79 and 75% and a CFR <2.6 with 83 and 82% sensitivity and specificity, respectively, using adjusted-receiver operating characteristic curve (ROC) analysis. CONCLUSIONS Elevated LV diastolic compressive forces on coronary microcirculation and the presence of generalized vascular damage may explain the association between PWV and CFR. PWV has an incremental value in the determination of impaired coronary microcirculation in hypertensive patients.


American Journal of Hypertension | 2009

Cognitive Impairment Is Related to Increased Arterial Stiffness and Microvascular Damage in Patients With Never-Treated Essential Hypertension

Helen Triantafyllidi; Chrysa Arvaniti; John Lekakis; Ignatios Ikonomidis; Nikolaos Siafakas; Stavros Tzortzis; Paraskevi Trivilou; Loukia Zerva; Eleftherios Stamboulis; Dimitrios Th. Kremastinos

BACKGROUND It is known that essential hypertension may be implicated in the development of cognitive impairment that is associated to microvascular disease of the brain. It has been hypothesized that increased arterial stiffness of the large arteries may lead to microvascular changes due to increased pulsatile flow. Our study tests the hypothesis that large artery stiffness and microvascular damage are related to brain microcirculation changes as reflected by impaired cognitive function. METHODS We studied 110 nondiabetic patients aged 40-80 years (mean age 53.8 +/- 11.2 years, 57 men) with recently diagnosed stage I-II essential hypertension. Mini-Mental State Examination (MMSE) was used as a screening test for global cognitive impairment. We performed both 2-D echocardiography and carotid-femoral pulse wave velocity (PWV) in order to evaluate arterial stiffness. Twenty-four hour urine microalbumin excretion was measured as a marker of microvascular damage. RESULTS In the entire population, MMSE was negatively correlated with age (r = -0.42, P < 0.001), 24-h pulse pressure (PP) (r = -0.18, P < 0.05), and PWV (r = -0.3, P = 0.003). Additionally, MMSE was not independently correlated with microalbuminuria in patients aged over 65 years (r = -0.58, P = 0.003). CONCLUSIONS Impaired cognitive function is associated with increased large artery stiffness and microalbumin excretion in newly diagnosed, untreated hypertensive patients. These findings support the hypothesis that cognitive impairment induced by impaired microcirculation is linked to large artery stiffness and microvascular damage.


Circulation-cardiovascular Imaging | 2014

Increased benefit of interleukin-1 inhibition on vascular function, myocardial deformation, and twisting in patients with coronary artery disease and coexisting rheumatoid arthritis.

Ignatios Ikonomidis; Stavros Tzortzis; Ioanna Andreadou; Ioannis Paraskevaidis; Chrysoula Katseli; Pelagia Katsimbri; George Pavlidis; John Parissis; Dimitrios Th. Kremastinos; Maria Anastasiou-Nana; John Lekakis

Background—We investigated the effects of anakinra, an interleukin-1 receptor antagonist, on coronary and left ventricular function in coronary artery disease (CAD) patients with rheumatoid arthritis. Methods and Results—In a double-blind crossover trial, 80 patients with rheumatoid arthritis (60 with CAD and 20 without) were randomized to a single injection of anakinra or placebo and after 48 hours to the alternative treatment. At baseline and 3 hours after treatment, we assessed (1) flow-mediated dilation of brachial artery; (2) coronary flow reserve, ejection fraction, systemic arterial compliance, and resistance by echocardiography; (3) left ventricular global longitudinal and circumferential strain, peak twisting, untwisting velocity by speckle tracking; and (4) interleukin-1&bgr;, nitrotyrosine, malondialdehyde, protein carbonyl, and Fas/Fas ligand levels. At baseline, patients with CAD had 3-fold higher interleukin-1&bgr;, protein carbonyl, higher nitrotyrosine, malondialdehyde, and Fas/Fas ligand than non-CAD (P<0.05). After anakinra, there was a greater improvement of flow-mediated dilation (57±4% versus 47±5%), coronary flow reserve (37±4% versus 29±2%), arterial compliance (20±18% versus 2±17%), resistance (−11±19% versus 9±21%), longitudinal strain (33±5% versus 18±2%), circumferential strain (22±5% versus 13±5%), peak twisting (30±5% versus 12±5%), untwisting velocity (23±5% versus 13±5%), ejection fraction (12±5% versus 0.5±5%), apoptotic and oxidative markers, and, in particular, of protein carbonyl (35±20% versus 14±9%) in CAD than in non-CAD patients (P<0.01). No changes in the examined markers were observed after placebo. Conclusions—Interleukin-1 inhibition causes a greater improvement in endothelial, coronary aortic function in addition to left ventricular myocardial deformation and twisting in rheumatoid arthritis patients with CAD than in those without. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT01566201.


Circulation | 2005

Myocardial Ischemia Induces Interleukin-6 and Tissue Factor Production in Patients With Coronary Artery Disease A Dobutamine Stress Echocardiography Study

Ignatios Ikonomidis; George Athanassopoulos; John Lekakis; Kyriaki Venetsanou; Margarita Marinou; Kimon Stamatelopoulos; Dennis V. Cokkinos; Petros Nihoyannopoulos

Background— Interleukin-6 (IL-6) and macrophage colony stimulating factor plasma levels are elevated in acute coronary syndromes. IL-6 has an inherent negative inotropic action and, with tissue factor (TF), mediates the ischemia-reperfusion myocardial injury. We hypothesized that inducible ischemia leads to cytokine production, TF expression, and consequently persistent left ventricular dysfunction after dobutamine stress echocardiography (DSE) in coronary artery disease patients. Methods and Results— DSE was performed in 103 patients with angiographically documented coronary artery disease. Blood samples were obtained at rest, at peak stress, and 30 minutes after cessation of dobutamine infusion for measurement of macrophage colony stimulating factor, IL-6, and TF. New or worsening wall motion abnormalities at peak stress and their duration into recovery were noted. Median IL-6 and TF levels were increased at peak stress and at 30 minutes into recovery compared with rest (2.7 and 2.4 versus 2.1 pg/mL for IL-6, 310 and 385 versus 266 pg/mL for TF [P<0.01] in patients with an ischemic response; n=55). Compared with rest, a greater release of IL-6 at peak stress and recovery was observed in patients with increasing number of ischemic segments at peak DSE (2 versus 3 to 4 versus 5 to 6 versus 7 to 8 segments; P=0.03). The time to recovery of wall motion abnormalities was also associated with IL-6 levels at peak stress and recovery (r=0.51 and r=0.39, P<0.05). Macrophage colony stimulating factor levels remained unchanged throughout DSE. Conclusions— Reversible ischemia induced during DSE increases IL-6 and TF plasma levels. IL-6 is related to the extent of left ventricular dysfunction at peak stress and to persistent LV dysfunction during recovery.


Journal of Hypertension | 2006

Impact of the time rate of blood pressure variation on left ventricular mass

Nikolaos Zakopoulos; Georgios Tsivgoulis; Gerassimos D. Barlas; Konstantinos Spengos; Efstathios Manios; Ignatios Ikonomidis; Savas Toumanidis; Konstantinos Dolianitis; K. Vemmos; Demetris Vassilopoulos; Spyridon D. Moulopoulos

Objectives Blood pressure (BP) changes are steeper in hypertensive than in normotensive individuals, whereas an increased rate of BP fluctuations is associated with medial hypertrophy of the carotid arteries. We evaluated the association between the rate of BP variation derived from ambulatory blood pressure monitoring (ABPM) data analysis and left ventricular mass (LVM). Methods ABPM and echocardiographic measurements of LVM were performed in 365 normotensive, 185 white-coat hypertensive (WCH) and 448 uncomplicated hypertensive individuals. Results The daytime and night-time rate of systolic blood pressure (SBP) and diastolic BP variation were significantly higher in hypertensive than in normotensive (P < 0.001) and WCH (P < 0.05) individuals. In the entire study population multiple linear regression models revealed independent determinants of LVM in the following rank order: body mass index (β + 0.266, P < 0.001), daytime SBP (β + 0.264, P < 0.001), male sex (β +0.220, P < 0.001), age (β + 0.203, P < 0.001), daytime heart rate (HR; β − 0.191, P < 0.001), daytime rate of SBP variation (β + 0.167, P < 0.001), and SBP dipping (β − 0.132, P < 0.001). A 0.1 mmHg/min increase in the daytime rate of SBP variation correlated with an increment of 7.087 g (95% confidence interval 4.775–9.399) in the LVM. The addition of the daytime rate of SBP variation in the multiple regression model for the prediction of LVM significantly increased the adjusted model R2 [R2 change 0.024 (2.4%); P for change < 0.001]. Conclusion Steeper BP variations may produce a greater stress on the left ventricular wall and may have an additive role to body habitus, BP and HR levels in the detection of cardiac hypertrophy. Target-organ damage in hypertensive patients, in addition to BP levels, dipping status and BP variability, may also be related to a steeper rate of BP oscillations.

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John Lekakis

National and Kapodistrian University of Athens

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John Parissis

National and Kapodistrian University of Athens

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Ioannis Paraskevaidis

National and Kapodistrian University of Athens

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Helen Triantafyllidi

National and Kapodistrian University of Athens

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Dimitrios Th. Kremastinos

National and Kapodistrian University of Athens

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Maria Anastasiou-Nana

National and Kapodistrian University of Athens

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Ioanna Andreadou

National and Kapodistrian University of Athens

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Stavros Tzortzis

National and Kapodistrian University of Athens

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Efstathios K. Iliodromitis

National and Kapodistrian University of Athens

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George Pavlidis

National and Kapodistrian University of Athens

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