Biomedical subjects

Alexandros P Patrianakos

Publications and source records attributed to Alexandros P Patrianakos.

11 recordsLinked to original sources

PubMed2006

Androgen deficiency and endothelial dysfunction in men with end-stage kidney disease receiving maintenance hemodialysis.

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 testosterone 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.

Adult↗

PubMed2006

Atrial fibrillation is associated with increased neurohumoral activation and reduced exercise tolerance in patients with non-ischemic dilated cardiomyopathy.

OBJECTIVES: To assess atrial fibrillation (AF) associated differences in proinflammatory cytokines, natriuretic peptide levels and exercise capacity in patients with heart failure (HF) secondary to non-ischemic dilated cardiomyopathy (NIDC). METHODS: We studied 147 NIDC patients, mean age 58.3+/-12.5 years, left ventricular (LV) ejection fraction 27.8+/-10.9% and NYHA class II-III. Neurohumoral activation was assessed by measurement of interleukin IL-1, IL-6, tumor necrosis factor-a (TNF-a), its soluble receptors sTNFR I and II, N-terminal atrial (NT-ANP) and -brain (NT-BNP) natriuretic peptide levels, and functional class was assessed by cardiopulmonary exercise test. RESULTS: Forty patients (27.5%) had chronic AF and they did not differ in age, LV ejection fraction or HF duration compared to patients in sinus rhythm (SR). AF was associated with increased levels of IL-6 (p=0.001), TNF-a (p=0.002), sTNFRI (p=0.023), NT-ANP (p<0.001) and NT-BNP (p=0.003), decreased exercise duration (p<0.001) and slightly reduced maximal oxygen consumption at peak exercise (p=0.07) compared to SR patients. No significant differences in cytokine and natriuretic peptide levels or exercise tolerance were noted when patients in AF were compared to the subgroup of SR with restrictive LV filling pattern. Multivariate analysis showed that NT-ANP (p=0.003) and IL-6 (p=0.006) plasma levels were independently associated with the presence of AF in our patient population. CONCLUSION: AF is associated with increased inflammatory state, natriuretic peptide levels and reduced exercise capacity in patients with HF secondary to NIDC. These findings suggest that the presence of AF in HF represents a more advanced stage of the syndrome.

Atrial Fibrillation↗

PubMed2006

Adiponectin and cardiovascular remodeling in end-stage renal disease and co-morbid diabetes mellitus.

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.

Adiponectin↗

PubMed2006

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

INTRODUCTION: Central 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. METHODS: In 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. RESULTS: There 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). CONCLUSION: The 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.

Aged↗

PubMed2005

Comparative efficacy of nebivolol versus carvedilol on left ventricular function and exercise capacity in patients with nonischemic dilated cardiomyopathy. A 12-month study.

PURPOSE: To compare the efficacy of nebivolol versus carvedilol on left ventricular (LV) function and exercise capacity in patients with nonischemic dilated cardiomyopathy (NIDC). METHODS: After enrollment in this double-blind trial, 72 patients, aged 55 +/- 9.5 years, with NIDC, LV ejection fraction (LVEF) < 45%, New York Heart Association classes II to III, were randomized to either nebivolol (34 patients) or carvedilol (38 patients) and were evaluated through echocardiography and exercise tests at baseline and 3 and 12 months after treatment. RESULTS: During follow-up, 4 patients discontinued nebivolol, although 3 patients stopped carvedilol. Patients in both the nebivolol and carvedilol groups showed a steady improvement in New York Heart Association class (P = .002 and < .001, at 12 months, respectively) and LVEF (P = .001 and < .001, at 12 months, respectively) that became significant from 3-month follow-up on. Intergroup analysis showed that carvedilol group had a greater increase in LVEF at 3 (P = .04) and 12 (P = .02) months' follow-up compared with nebivolol group. Advanced diastolic dysfunction regressed to earlier stages in carvedilol patients after 3 (P = .02) and 12 (P = .01) months' treatment, whereas in the nebivolol group, a significant improvement in diastolic dysfunction was found at the 12 months' follow-up (P = .02). Exercise duration improved in both groups at 12 months' follow-up (both P = .01), but in the nebivolol group, there was an initial deterioration at 3 months (P = .07). CONCLUSIONS: Both nebivolol and carvedilol appear relatively safe, with beneficial effects on LV systolic and diastolic function as well as exercise capacity in patients with NIDC after 12 months' treatment. However, carvedilol exhibits more favorable effects on LV function than does nebivolol.

Benzopyrans↗

PubMed2005

Peripheral arterial embolism due to a left ventricular diverticulum in a young adult.

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.

Adult↗

PubMed2005

AI-700 (Acusphere).

Acusphere is developing AI-700, perflubutane-filled synthetic polymer microspheres, for potential use as an ultrasound contrast agent for the assessment of myocardial perfusion. By April 2005, phase III enrollment was expected to be complete by early 2006, and the company expected to file an NDA in the first half of 2006.

Clinical Trials as Topic↗

PubMed2004

Regional coronary flow and contractile reserve in patients with idiopathic dilated cardiomyopathy.

OBJECTIVES: The purpose of this study was to assess regional coronary flow and contractile reserve in patients with idiopathic dilated cardiomyopathy (IDCM). BACKGROUND: Although IDCM has been associated with alterations in coronary blood flow and contractile reserve, little is known about their regional distribution and correlation. METHODS: Fourteen patients with IDCM and 11 control subjects underwent coronary flow velocity (APV) measurements in the left anterior descending (LAD), left circumflex (LCx), and right coronary (RCA) arteries at baseline (b) and at maximal hyperemia (h). Coronary flow reserve (CFR) was defined as h-APV/b-APV. Wall thickening was assessed in 16 segments (7 assigned to LAD, 5 to LCx, and 4 to RCA) both at rest and under peak stress during low-dose dobutamine echocardiography. Regional contractile reserve was defined as the percentage difference in wall motion score index between rest and stress in each vascular territory. RESULTS: Although there were no significant differences in b-APV, patients with IDCM had significantly lower h-APV than controls in all three vascular territories and reduced CFR (LAD: 2.79 +/- 0.43 vs. 3.48 +/- 0.51, p < 0.05; LCx: 2.71 +/- 0.39 vs. 3.36 +/- 0.65, p < 0.05; and RCA: 3.43 +/- 0.55 vs. 4.02 +/- 0.73, p < 0.05). There was also a significant correlation between CFR and the corresponding contractile reserve in the vascular territory of the LAD (r = 0.75, p = 0.002) and the LCx (r = 0.64, p = 0.014). CONCLUSIONS: Patients with IDCM have alterations in regional coronary flow and reduced CFR. Furthermore, the correlation between regional CFR and the corresponding contractile reserve indicates that microvascular dysfunction may have a pathophysiologic role in the evolution of the disease.

Blood Flow Velocity↗

PubMed2004

Late left ventricular diastolic flow propagation velocity determined by color M-mode Doppler in the assessment of diastolic dysfunction.

BACKGROUND: Early color M-mode Doppler flow propagation (Ep) through the left ventricle (LV) has been proposed as a useful noninvasive index for assessing LV relaxation, whereas data concerning late velocity propagation (Ap) is lacking. METHODS: We studied 51 patients with delayed relaxation (group I) and 50 with pseudonormal filling pattern (group II). Another 51 aged-matched healthy persons served as the control group. RESULTS: Patients showed increased left atrial dimensions, atrial wave of the pulmonary vein flow, and Ap, and reduced LV ejection fraction, Ep, and Ep/Ap ratio compared with the control group. Patients in group II revealed increased left atrial dimensions (P =.001), atrial wave of the pulmonary vein flow (P <.001), and Ep/Ap ratio (P <.001), and reduced LV ejection fraction and Ap (P <.001) compared with group I. Regression analysis showed that the strongest independent variable distinguishing normal from pseudonormal filling pattern was the Ep/Ap ratio. CONCLUSION: Ap evaluation offers a new diagnostic diastolic index, especially in the field of the pseudonormal pattern where the separation from normal is difficult.

Adult↗

PubMedDate not supplied

Effects of Nebivolol on left ventricular function and exercise capacity in patients with non-ischaemic dilated cardiomyopathy. A randomised placebo-controlled study.

INTRODUCTION: This study assessed the effects of Nebivolol on left ventricular (LV) function and exercise capacity in patients with non-ischaemic dilated cardiomyopathy (NIDC). METHODS: After enrolment in this double-blind trial, 60 patients, aged 55 +/- 9.5 years, with angiographically proven NIDC, LV ejection fraction (EF) < 45%, NYHA class II-III, were randomised to either Nebivolol (target dose 5 mg) or placebo and were evaluated using echocardiography and exercise tests over 3 months. RESULTS: There were no baseline differences between the 2 groups regarding NYHA class, heart rate (HR), blood pressure (BP), LVEF or other echocardiographic variables. During follow-up, 4 patients in the Nebivolol and 5 in the placebo group discontinued treatment. After 3-months' treatment a significant decrease in NYHA class (p = 0.001), resting HR (p = 0.03), systolic and diastolic BP (both p < 0.001), left atrial diameter (p = 0.01) and LV end-systolic volume (p = 0.046), and an increase in LVEF (p = 0.01) were observed in the Nebivolol group compared to placebo. The atrial contribution to total LV filling (p = 0.007) and the pulmonary venous (PV) systolic wave velocity (p = 0.007) increased, whereas the atrial PV component decreased (p < 0.001) in the Nebivolol patients compared to placebo. Exercise duration decreased at 3 months (p = 0.01) compared to placebo, probably as a result of reduced maximal exercise HR (p < 0.001). CONCLUSIONS: Nebivolol is a safe and well-tolerated drug that improves NYHA class, systolic and diastolic LV function in NIDC patients, although it is associated with a lower maximal exercise duration at 3 months.

Adrenergic beta-Antagonists↗

PubMedDate not supplied

Association of impaired glucose tolerance with increased heart rate and subclinical inflammation.

INTRODUCTION: This study was designed to assess possible alterations in heart rate (HR), heart rate variability (HRV) and circulating serum levels of proinflammatory cytokines in patients with impaired glucose tolerance (IGT). METHODS: Forty-five patients, aged 34-68 years, with IGT were compared with 28 age-matched healthy controls. Using a 24-hour ambulatory electrocardiogram, we calculated mean HR during daytime (HR-D), night-time (HR-N) and the entire 24-hour period (HR-24h), as well as time domain HRV parameters. From blood samples interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-a) and its soluble receptor (sTNFRII) were also calculated by immunoassay. RESULTS: Patients showed higher mean HR compared to controls and significantly elevated circulating levels of TNF-a, sTNFRII, and IL-6. Pearson correlation analysis showed that TNF-a was positively correlated with mean HR-D (r: 0.304, p=0.042). IL-6 was also positively correlated with mean HR-24h (r: 0.299, p=0.046) and with mean HR-D (r: 0.410, p=0.005). CONCLUSION: IGT patients have an increased HR and elevated cytokine levels. These changes could serve as an index of the primary atherosclerotic process.

Adult↗