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Dive into the research topics where Alexandros P. Patrianakos is active.

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Featured researches published by Alexandros P. Patrianakos.


Critical Care | 2006

Real-time ultrasound-guided catheterisation of the internal jugular vein: a prospective comparison with the landmark technique in critical care patients

Dimitrios Karakitsos; Nicolaos Labropoulos; Eric de Groot; Alexandros P. Patrianakos; Gregorios Kouraklis; John Poularas; George Samonis; Dimosthenis Tsoutsos; Manousos M. Konstadoulakis; Andreas Karabinis

IntroductionCentral venous cannulation is crucial in the management of the critical care patient. This study was designed to evaluate whether real-time ultrasound-guided cannulation of the internal jugular vein is superior to the standard landmark method.MethodsIn this randomised study, 450 critical care patients who underwent real-time ultrasound-guided cannulation of the internal jugular vein were prospectively compared with 450 critical care patients in whom the landmark technique was used. Randomisation was performed by means of a computer-generated random-numbers table, and patients were stratified with regard to age, gender, and body mass index.ResultsThere were no significant differences in gender, age, body mass index, or side of cannulation (left or right) or in the presence of risk factors for difficult venous cannulation such as prior catheterisation, limited sites for access attempts, previous difficulties during catheterisation, previous mechanical complication, known vascular abnormality, untreated coagulopathy, skeletal deformity, and cannulation during cardiac arrest between the two groups of patients. Furthermore, the physicians who performed the procedures had comparable experience in the placement of central venous catheters (p = non-significant). Cannulation of the internal jugular vein was achieved in all patients by using ultrasound and in 425 of the patients (94.4%) by using the landmark technique (p < 0.001). Average access time (skin to vein) and number of attempts were significantly reduced in the ultrasound group of patients compared with the landmark group (p < 0.001). In the landmark group, puncture of the carotid artery occurred in 10.6% of patients, haematoma in 8.4%, haemothorax in 1.7%, pneumothorax in 2.4%, and central venous catheter-associated blood stream infection in 16%, which were all significantly increased compared with the ultrasound group (p < 0.001).ConclusionThe present data suggest that ultrasound-guided catheterisation of the internal jugular vein in critical care patients is superior to the landmark technique and therefore should be the method of choice in these patients.


American Journal of Nephrology | 2006

Androgen Deficiency and Endothelial Dysfunction in Men with End-Stage Kidney Disease Receiving Maintenance Hemodialysis

Dimitrios Karakitsos; Alexandros P. Patrianakos; Eric de Groot; John Boletis; Andreas Karabinis; John Kyriazis; George Samonis; Frangiskos I. Parthenakis; Panos E. Vardas; Eugene Daphnis

Objectives and Methods: Two thirds of men with end-stage kidney disease (ESKD) have serum testosterone levels in the hypogonadal range. We examined if low serum testoster- one levels were correlated with measures of endothelial dysfunction in ESKD. Bilateral common carotid artery (CCA) intima-media thickness (IMT) and atherosclerotic plaque occurrence, left ventricular mass index, flow- (FMD) and nitrate-mediated vasodilatation (NMD) of the brachial artery were determined by ultrasound imaging in 100 nondiabetic men with ESKD (50 men exhibited androgen deficiency; serum testosterone concentrations <300 ng/dl). Results: Left-ventricular mass index, CCA diameter, CCA-IMT and atherosclerotic plaque occurrence were all significantly increased in ESKD patients with androgen deficiency compared with patients without androgen deficiency (p < 0.05). Also, FMD and NMD measurements were significantly reduced in the former compared with the latter (p < 0.05). Testosterone levels were inversely correlated with age and duration of hemodialysis therapy (r = –0.44 and r = –0.55; p < 0.001). Testosterone levels were negatively correlated to CCA-IMT and atherosclerotic plaque occurrence in patients with androgen deficiency (r = –0.32, p < 0.003, and r = –0.23, p < 0.04, respectively). FMD and NMD measurements were positively correlated to total (r = 0.65 and r = 0.61; both p < 0.0001) and free (r = 0.52 and r = 0.48; both p < 0.001) testosterone levels in patients with low androgenicity. Conclusion: The present results indicated that ESKD patients with androgen deficiency had increased CCA-IMT, atherosclerotic plaque occurrence and reduced FMD and NMD compared with patients without androgen deficiency. Testosterone serum levels were negatively correlated to CCA-IMT and positively correlated to endothelium-dependent vasodilatation in ESKD patients with androgen deficiency.


European Journal of Echocardiography | 2009

Proximal aortic stiffness is related to left ventricular function and exercise capacity in patients with dilated cardiomyopathy

Alexandros P. Patrianakos; Fragiskos I. Parthenakis; Dimitrios Karakitsos; Eva Nyktari; Panos E. Vardas

AIMS Patients with heart failure (HF) show abnormal arterial stiffening. METHODS AND RESULTS We examined 60 patients (52.1 +/- 12, 8 years) with non-ischaemic dilated cardiomyopathy (NIDC), New York Heart Association II-III, in sinus rhythm, left ventricular ejection fraction 30.1 +/- 8.6%, and 44 normals. All subjects underwent an echocardiographic study and a cardiopulmonary exercise test. We evaluated the segmental proximal aorta (AO) pulse wave velocity (PWV) in the region of aortic arch with a new echo-method: from the suprasternal view, the distance between ascending and descending AO was measured with two-dimensional ultrasound, and the aortic flow wave transit time (TT) was measured with pulsed-wave Doppler. Pulse wave velocity was calculated as aortic distance/TT. Patients showed increased PWV (7.4 +/- 2.9 vs. 4.8 +/- 1.1 m/s, P < 0.001), compared with controls. Patients with advanced left ventricular (LV) (restrictive or pseudo-normal filling pattern) diastolic dysfunction showed increased PWV (8.6 +/- 2.6 vs. 6.6 +/- 2.9 m/s, P = 0.01) and reduced peak and predicted (for age, sex, and body mass) VO(2) (both P < 0.001), compared with those with mild diastolic dysfunction (delayed relaxation filling pattern). Pulse wave velocity was significantly correlated with the LV mass (r = 0.32, P = 0.01), the peak spectral tissue Doppler imaging systolic wave (r = -0.34, P = 0.006), the LV diastolic filling pattern (r = 0.42, P = 0.001), and the peak (r = -0.47, P < 0.001) and predicted VO(2) (r = -0.579, P < 0.001). CONCLUSION Patients with NIDC showed increased proximal aortic stiffness, which relates to LV systolic and diastolic function and exercise capacity. The echocardiographic assessment of the regional aorta PWV seems to be clinically important.


Cardiovascular Pathology | 2008

Myocardial sympathetic innervation in patients with impaired glucose tolerance: relationship to subclinical inflammation

Georgios F. Diakakis; Fragiskos I. Parthenakis; Alexandros P. Patrianakos; Sofia Koukouraki; Maria Stathaki; Nikos Karkavitsas; Panos E. Vardas

AIM This study was designed to assess cardiac adrenergic nerve activity, using iodine (I)-123-labeled metaiodobenzylguanidine (MIBG), in patients with impaired glucose tolerance (IGT) and to investigate its relation to circulating levels of proinflammatory cytokines. METHODS We studied 22 patients with IGT (aged 34-68 years) and 18 age-matched healthy controls, using I-123 MIBG cardiac imaging. The early (10 min) and late (4 h) heart to mediastinum MIBG uptake (H/M) ratio and washout were calculated. Levels of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-a), and its soluble receptor [soluble TNF receptor II (sTNFRII)] were measured by immunoassay of blood samples from patients and controls. RESULTS The early and late MIBG uptake was lower (both P<.001) and the WR was higher (P<.001) in patients than in controls. The analysis showed innervation defects in 20 of the 22 patients. Nearly half (45.4%) showed severe adrenergic innervation defects in both the inferior wall and the apex. Regarding cytokines, patients showed significantly elevated TNF-a (P=.005), sTNFRII (P<.001), and IL-6 (P<.001) levels compared to controls. IL-6 and sTNFRII were found to correlate with the WR (r=0.468, P=.028 and r=0.455, P=.034, respectively). CONCLUSION Patients with IGT show reduced MIBG cardiac uptake with a segmental pattern. The reduced cardiac sympathetic innervation was related to the elevated proinflammatory cytokine levels and could be considered an index of early atherosclerotic process in these patients.


American Journal of Nephrology | 2006

Adiponectin and Cardiovascular Remodeling in End-Stage Renal Disease and Co-Morbid Diabetes Mellitus

Dimitrios Karakitsos; Eric de Groot; Alexandros P. Patrianakos; Frangiscos Parthenakis; John Boletis; Andreas Karabinis; John Kyriazis; Panos E. Vardas; Eugene Daphnis

Objectives and Methods: Altered plasma high-sensitivity C-reactive protein (hs-CRP) and adiponectin (ADP) may contribute to increased vascular inflammation and accelerated atherosclerosis in patients with end-stage renal disease (ESRD) and co-morbid diabetes. Common carotid artery intima-media thickness (CCA-IMT) and atherosclerotic plaque occurrence, left-ventricular mass index (LVMI), and pulse wave velocity of the proximal aorta (PWVr) were determined by ultrasound imaging in 120 ESRD (55 diabetic) patients, and 83 age-, sex-, and blood pressure-matched controls. Also, plasma levels of ADP and hs-CRP were determined and their relationships with the above cardiovascular alterations were analyzed. Results: LVMI, PWVr, CCA-IMT and atherosclerotic plaque occurrence were all increased in ESRD patients compared to controls (all p < 0.001). LVMI (p < 0.05), PWVr (p < 0.001), CCA-IMT (p < 0.001) and atherosclerotic plaque occurrence (p < 0.001) were increased in diabetic compared to nondiabetic ESRD patients. Hs-CRP levels were increased and ADP levels were decreased in diabetic compared to nondiabetic ESRD patients (both p < 0.001). ADP levels correlated inversely with hs-CRP (r = –0.473, p < 0.0001) in ESRD patients. Hs-CRP was positively correlated with LVMI (r = 0.365, p < 0.0001), PWVr (r = 0.42, p < 0.0001) and CCA-IMT (r = 0.18, p = 0.047) while ADP inversely correlated with PWVr (r = –0.263, p = 0.0035) and CCA-IMT (r = –0.207, p = 0.022) in ESRD patients. Conclusion: The present results indicate diabetic disease-specific alterations in the biochemical parameters of hs-CRP and ADP in ESRD patients. The above biochemical parameters were intimately linked to the cardiovascular measurements of LVMI, PWVr and CCA-IMT in patients with ESRD and co-morbid diabetes mellitus.


Chest | 2005

Peripheral Arterial Embolism Due to a Left Ventricular Diverticulum in a Young Adult

Fragiskos I. Parthenakis; George E. Kochiadakis; Alexandros P. Patrianakos; Mihalis I. Hamilos; Ioanna Mitrouska; Asterios N. Katsamouris; Panos E. Vardas

A 32-year-old man was admitted to the emergency department of our hospital after experiencing a peripheral arterial embolism. Investigation of the possible embolic sources in an otherwise asymptomatic patient revealed the existence of a left ventricular diverticulum. The left ventricular diverticulum is a rare congenital anomaly, either isolated or as a part of a syndrome including other congenital malformations. The treatment of choice, especially in symptomatic patients, is surgical resection, while in asymptomatic patients anticoagulation therapy is indicated.


American Journal of Cardiology | 2003

Relation of cardiac sympathetic innervation to proinflammatory cytokine levels in patients with heart failure secondary to idiopathic dilated cardiomyopathy

Fragiskos I. Parthenakis; Alexandros P. Patrianakos; Vasilis Prassopoulos; Evangelos A. Papadimitriou; Dragana Nikitovic; Nikos S. Karkavitsas; Panos E. Vardas

Experimental studies have shown that cytokine production by the heart may be regulated by sympathetic nervous system stimulation of cardiac beta-adrenergic receptors. Proinflammatory cytokine levels are increased in heart failure, whereas cardiac fixation of 123-I-metaiodobenzylguanidine (MIBG) has been used to study myocardial adrenergic innervation. This study was designed to assess the relation between cardiac MIBG uptake and circulating levels of proinflammatory cytokines in patients with idiopathic dilated cardiomyopathy (IDC). Forty-seven patients (12 women; mean age 56.5 +/- 9 years) with angiographically proved IDC, in New York Heart Association functional classes II to III, and who had left ventricular ejection fraction 30.6 +/- 9.5%, and 20 healthy controls were studied with planar MIBG. The early (10 minutes) and late (4 hours) heart to mediastinum uptake ratio and washout were calculated. Circulating plasma levels of interleukins (IL)-1 and IL-6, tumor necrosis factor-alpha, and solube receptors of TNF (sTNFR) I and II were measured. The patient group had significantly lower values of MIBG uptake at 10 minutes (p <0.001) and 4 hours (p <0.001) and higher washout (p <0.001) than the controls. Late MIBG uptake was significantly correlated with New York Heart Association class (r = -0.42, p = 0.02), left ventricular ejection fraction (r = 0.34, p = 0.01), left ventricular systolic wall stress (r = -0.40, p = 0.05), oxygen consumption at peak exercise (r = 0.32, p = 0.03), IL-1 (r = -0.55, p <0.001), TNF (r = -0.33, p = 0.02), and sTNFRII (r = -0.44, p = 0.001). Multivariate linear regression analysis revealed that MIBG at 4 hours was independently associated with IL-1 levels (p <0.001). Thus, reduced cardiac sympathetic innervation in heart failure is associated with elevated levels of inflammatory cytokines, suggesting that it has a potential inflammatory effect via modulation of the cardiac production of these cytokines.


Hemodialysis International | 2007

Can a left internal jugular catheter be used in the hemodialysis of a patient with persistent left superior vena cava

Konstantinos Stylianou; Konstantinos Korsavas; Argyro Voloudaki; Alexandros P. Patrianakos; Eleftheria Vardaki; Nikolaos Tzenakis; Eugene Daphnis

A patient with a persistent left superior vena cava (PLSVC) was incidentally diagnosed after positioning of a dual lumen catheter for hemodialysis into the left internal jugular vein. Although PLSVC is a relatively rare condition, it is the most common congenital anomaly of thoracic venous circulation. It represents the persistence of the left horn of the embryonic sinus venosus, which normally involutes during embryogenesis to become the coronary sinus. The existence of a PLSVC can cause a significant diagnostic dilemma during catheterization of the left internal jugular vein, pertaining to the positioning of the catheter. It may also be associated with significant clinical implications such as systemic embolization, provocation of arrhythmia, and thrombosis of the vessel. The safety of such catheterization has not been adequately evaluated due to the rarity of this condition. We believe that a diagnostic workup including blood gas analysis, echocardiography, and computed tomography is necessary to confirm a right atrial drainage and a patent innominate vein as prerequisites to maintain the catheter in position.


International Journal of Cardiology | 2012

Arrhythmogenic right ventricular cardiomyopathy/dysplasia and troponin release. Myocarditis or the "hot phase" of the disease?

Alexandros P. Patrianakos; Nikos Protonotarios; Evangelia Nyktari; K. Pagonidis; Adalena Tsatsopoulou; Frangiskos I. Parthenakis; Panos E. Vardas

A 21-year-old man was admitted due to sustained palpitations and an episode of presyncope. Twelve-lead resting ECG revealed sustained ventricular tachycardia with an average rate of 220 bpm, LBBB configuration and superior axis (Fig. 1A). The patient was hemodynamically stable with arterial blood pressure 110/80 mm Hg and was converted to sinus rhythm (SR) with bolus infusion of 150 mg amiodarone over 10 min. After conversion to SR, a new 12-lead ECG exhibited inverted T waves in leads V1 to V4 and frequent ventricular extrasystoles of LBBB type and axis similar to that of VT (Fig. 1B). Detailed history revealed that at the age of 15, the patient had suffered similar episodes of sustained palpitations and presyncope, especially after exercise. Cardiac evaluation at that time demonstrated inverted T waves in leads V1 and V2 on 12-lead ECG but no functional/ structural alterations on two-dimensional echocardiography were reported. Therewas no family history of cardiac disease or sudden cardiac death. Furthermore, he denied any recent infection. The patient underwent two-dimensional echocardiography that revealed dilatation of the right ventricle (RV outflow tract enddiastolic diameter was 36 mm and 41 mm, on parasternal long axis


European Journal of Heart Failure | 2010

Myocardial gene expression alterations in peripheral blood mononuclear cells of patients with idiopathic dilated cardiomyopathy

Joanna E. Kontaraki; Fragiskos I. Parthenakis; Eva Nyktari; Alexandros P. Patrianakos; Panos E. Vardas

To assess cardiac gene expression in peripheral blood cells of patients with idiopathic dilated cardiomyopathy (IDCM) and its relationship to echocardiographic left ventricular (LV) function.

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Eva Nyktari

Imperial College London

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Dimitrios Karakitsos

University of Southern California

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Eugene Daphnis

Texas Tech University Health Sciences Center

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