Spyridon Koulouris

Ascorbic Acid Reverses Endothelial Vasomotor Dysfunction in Patients With Coronary Artery Disease

BACKGROUND In the setting of atherosclerosis, endothelial vasomotor function is abnormal. Increased oxidative stress has been implicated as one potential mechanism for this observation. We therefore hypothesized that an antioxidant, ascorbic acid, would improve endothelium-dependent arterial dilation in patients with coronary artery disease. METHODS AND RESULTS Brachial artery endothelium-dependent dilation in response to hyperemia was assessed by high-resolution vascular ultrasound before and 2 hours after oral administration of either 2 g ascorbic acid or placebo in a total of 46 patients with documented coronary artery disease. Plasma ascorbic acid concentration increased 2.5-fold 2 hours after treatment (46+/-8 to 114+/-11 micromol/L, P=.001). In the prospectively defined group of patients with an abnormal baseline response (<5% dilation), ascorbic acid produced marked improvement in dilation (2.0+/-0.6% to 9.7+/-2.0%), whereas placebo had no effect (1.1+/-1.5% to 1.7+/-1.5%, P=.003 for ascorbic acid versus placebo). Ascorbic acid had no effect on hyperemic flow or arterial dilation to sublingual nitroglycerin. CONCLUSIONS Ascorbic acid reverses endothelial vasomotor dysfunction in the brachial circulation of patients with coronary artery disease. These findings suggest that increased oxidative stress contributes to endothelial dysfunction in patients with atherosclerosis and that endothelial dysfunction may respond to antioxidant therapy.

Low Plasma Ascorbic Acid Independently Predicts the Presence of an Unstable Coronary Syndrome

OBJECTIVES This study sought to investigate the relations between plasma antioxidant status, extent of atherosclerosis and activity of coronary artery disease. BACKGROUND Previous studies indicate that increased antioxidant intake is associated with decreased coronary disease risk, but the underlying mechanisms remain controversial. METHODS Plasma samples were obtained from 149 patients undergoing cardiac catheterization (65 with stable angina, 84 with unstable angina or a myocardial infarction within 2 weeks). Twelve plasma antioxidant/oxidant markers were measured and correlated with the extent of atherosclerosis and the presence of an unstable coronary syndrome. RESULTS By multiple linear regression analysis, age (p < 0.001), diabetes mellitus (p < 0.001), male gender (p < 0.001) and hypercholesterolemia (p = 0.02) were independent predictors of the extent of atherosclerosis. No antioxidant/oxidant marker correlated with the extent of atherosclerosis. However, lower plasma ascorbic acid concentration predicted the presence of an unstable coronary syndrome by multiple logistic regression (odds ratio [OR] 0.59, 95% confidence interval [CI] 0.40 to 0.89, p = 0.01). The severity of atherosclerosis also predicted the presence of an unstable coronary syndrome (OR 1.7, 95% CI 1.14 to 2.47, p = 0.008) when all patients were considered. When only patients with significant coronary disease were considered (at least one stenosis >50%), ascorbic acid concentration (OR 0.56, 95% CI 0.37 to 0.85, p = 0.008) and total plasma thiols (OR 0.52, 95% CI 0.34 to 0.80, p = 0.004) predicted the presence of an unstable coronary syndrome, whereas the extent of atherosclerosis did not. CONCLUSIONS These data are consistent with the hypothesis that the beneficial effects of antioxidants in coronary artery disease may result, in part, by an influence on lesion activity rather than a reduction in the overall extent of fixed disease.

Neutrophil Count on Admission Predicts Major In‐hospital Events in Patients with a Non‐ST‐Segment Elevation Acute Coronary Syndrome

Inflammation plays a key role in the pathogenesis of acute coronary syndromes (ACS). In this context we assessed neutrophil count as a predictor of major in‐hospital events in patients admitted for a non‐ST‐segment elevation (NSTE) ACS.

SHOULD WE MEASURE ROUTINELY OXIDIZED AND SMALL DENSE LOW-DENSITY LIPOPROTEINS IN SUBJECTS WITH TYPE 2 DIABETES?

Beyond low‐density lipoprotein (LDL)‐cholesterol concentrations, in recent years, several clinical studies have shown that both oxidised and small, dense LDL have a strong predictive role for the presence of vascular atherosclerosis. These two lipid parameters seem to have a synergistic impact on cardiovascular risk, with a greater importance in patients at higher‐risk, such as those with type‐2 diabetes. Increased levels of oxidised and small, dense LDL levels are a feature of diabetic dyslipidaemia, and small, dense LDL have been shown to be a good predictor of future cardiovascular events, at both univariate and multivariate analyses. On the other hand, although the association of oxidised LDL with surrogate markers of atherosclerosis is consistent, the correlation with hard clinical end points seems to be smaller. Yet, measurement of these two lipid parameters has not been widely used in daily practice because of the limited availability of clinical data and methodological problems: lack of availability of easy, cheap and reproducible essays for measurement of oxidised and, particularly, small, dense LDL has reduced their assessment in large clinical end‐points trials. However, on the basis of available data, the therapeutic modulation of small, dense LDL is significantly associated with reduced cardiovascular risk, even after adjustment for confounding factors. In conclusion, the routine measurement of oxidised and small, dense LDL in patients with type‐2 diabetes cannot be recommended in daily clinical practice so far; yet, their measurement is strongly encouraged to better understand their role on the cardiovascular risk of patients with type‐2 diabetes.

Histologic Findings of the Sinus Node and the Perinodal Area in Street Heroin Addicts, Victims of Sudden Unexpected Death

Abstract:  Sudden unexpected death is frequent in street heroin addicts. We conducted a histologic study of the sinus node (SN) to offer some evidence about the possible arrhythmogenic cause of death. Postmortem coronary angiography and microscopic examination of the SN and the perinodal area were performed in 50 heroin addicts (group 1) and in 50 nonaddicts (group 2), all men (16–40 years old). In heroin addicts, fatty and/or fibrous tissue replaced SN tissue in 21 cases (42%). Perinodal infiltration was found in 15 cases (30%). Fibromuscular dysplasia in branches of the sinus node artery (SNA) was found in eight cases (16%). Inflammation with focal and/or diffuse concentration of round cells was detected in the SN in 22 cases (44%). Old mural thrombi were also found in 13 cases (26%). The histologic changes in the SN and perinodal area offer an explanation about the possible mechanism of arrhythmia and sudden death in this population.

Sinus node artery originating from the posterior part of the right coronary artery.

PurposeThe purpose of the study was to examine the anatomical variations of the sinus node artery (SNA).MethodsGross anatomical examination, angiographic evaluation and if necessary dissection were performed in 200 human hearts derived from victims of various accidents.ResultsThe SNA was a branch of the right coronary artery in 118 [59%] cases, the left circumflex in 78 [39%] cases and both coronary arteries in 4 [2%] cases. In one subject, the SNA was found to arise from the distal part of the right coronary artery.ConclusionsIn our case, the sinus node was perfused by a SNA arising from the mid-posterior segment of the right coronary artery. Knowledge of this anatomical variation is useful for anatomists and of clinical significance for the interventional cardiologists and mainly for the cardiac surgeons in planning the surgical procedures.

Thiazolidinediones Anti-Inflammatory and Anti-Atherosclerotic Effects in Type 2 Diabetes Mellitus

Atherosclerosis is a major vascular complication of diabetes and the primary cause of mortality in patients with this disease. Inflammation has been implicated in the pathogenesis, progression and complications of both atherosclerosis and diabetes type 2, and these two complex disorders are often found intertwined in the patients. Peroxisome proliferatoractivated receptors-γ (PPARs-γ) are nuclear receptors that have been involved as transcriptional mediators in glucose homeostasis, lipid metabolism, and adipogenesis. PPAR-γ agonists, the thiazolidinediones (TZDs) are antidiabetic drugs that increase insulin sensitivity, lower blood glucose, decrease triglycerides and free fat acids and seem to have antiinflammatory effects as they reduce inflammatory markers and improve cardiovascular risk factors. All the major cell types in the vasculature express PPAR-γ including macrophages and vascular smooth muscle found cells in human atheroma. Activation of PPAR-γ by thiazolidinediones blocks vascular smooth muscle cells growth and migration thus reducing atherosclerosis. Several clinical studies have illustrated the beneficial role of thiazolidinediones in the atherosclerosis process, as they ameliorate endothelial dysfunction, reduce intima media thickness (IMT) in the carotid arteries and the restenosis rate after coronary stent implantation. However, recent trials have raised significant concerns about the deleterious action of thiazolidinediones, particularly rosiglitazone, on the cardiovascular system. Weighing the potential beneficial and harmful role of thiazolidinediones and exploring the possible mechanisms may provide a thorough view about the optimum clinical use of these compounds.

Ivabradine: a Selective If Current Inhibitor in the Treatment of Stable Angina

The role of heart rate reduction in the management of myocardial ischemia and chronic stable angina is pivotal. However, broad use and appropriate dosing of commonly used rate-slowing drugs is limited by their poor tolerability. Ivabradine is a selective inhibitor of the If currents of the sinoatrial node cells. If currents activity determines the slope of the depolarization curve towards the threshold level controlling heart rate in patients with sinus rhythm. Ivabradine, a compound of the benzocyclobutane (S 16257), exhibits a unique specificity for the If current and has a more favorable profile of adverse reactions compared to other If inhibitors. Accordingly, ivabradine has been used in the treatment of stable angina, where it presented anti-anginal and anti-ischemic effects equivalent to the effects of atenolol and amlodipine. Clinical studies proved the efficacy of ivabradine in patients with stable angina, while clinical data are awaited to verify its probable value in the treatment of atrial tachyarrhythmias and tachycardia due to ventricular dysfunction. Thus, the clinical value of ivabradine, which has completed clinical development for stable angina, is expected to exceed its role in the treatment of myocardial ischemia. In this context, ivabradine, promising efficacious and safe pharmacological management of heart rate, is a huge step in cardiovascular therapeutics.

The Impact of Reducing Hypertensive Left Ventricular Hypertrophy on Sudden Cardiac Death

The present case report describes a patient who sustained an acute inferior wall myocardial infarction, but initially remained clinically stable, then he underwent a successful coronary angioplasty and stenting procedure of a totally occluded right coronary artery, subsequently developing a dramatic clinical course with cardiogenic shock and cardiac arrest due to acute stent thrombosis which was successfully managed with repeat coronary angioplasty. We attributed this discrepant clinical manifestation of acute coronary occlusion to coronary collaterals, initially being present and then disappearing following the recanalization procedure, as being responsible for the dramatic clinical picture following the stent thrombosis.Aim: The purpose of this investigation was to collect data on the appropriate nursing care to patients supported with an intra-aortic balloon pump (IABP).Patients: All 39 patients who were supported with an IABP during the year 2006 (23 men ??? 16 women) took part in this investigation. They received nursing and medical care in the Intensive Care Cardiovascular Unit (ICCU) of Evagelismos General Hospital of Athens.Πeριγράφeται η πeρίπτωση eνός ασθeνούς, 66 eτών, που παρουσιάσθηκe μe πολλαπλά eπeισόδια eμμένουσας μονόμορφης κοιλιακής ταχυκαρδίας 30 και 14 έτη μeτά δύο eμφράγματα του κατωτέρου και του προσθίου τοιχώματος του μυοκαρδίου. Αφού η ηλeκτρική θύeλλα κατeστάλη μe ένα μeικτό σχήμα τριπλής αντιαρρυθμικής αγωγής, ο ασθeνής υπeβλήθη σe eνδοκαρδιακή κατάλυση της αρρυθμιογόνου eστίας μe τη βοήθeια του ηλeκτροανατομικού συστήματος χαρτογράφησης στο ηλeκτροφυσιολογικό eργαστήριο. Ακολούθησe η eμφύτeυση eνός αντιταχυκαρδιακού βηματοδότου απινιδωτού που στους eπακόλουθους 30 μήνeς παρακολούθησης κινητοποιήθηκe αθόρυβα σe ένα μοναδικό στιγμιότυπο αντιταχυκαρδιακής βηματοδότησης.Ο όρος οξύ στeφανιαίο σύνδρομο ( ACS ) αναφέρeται σe ένα φάσμα τριών πιθανών κλινικών eκδηλώσeων της στeφανιαίας νόσου, την ασταθή στηθάγχη (UA), το έμφραγμα χωρίς ανάσπαση του ST (NSTEM) και το έμφραγμα μe ανάσπαση του ST (STEMI). Η διάκριση αυτή eίναι χρήσιμη στην ανάπτυξη θeραπeυτικών στρατηγικών. Το Αμeρικανικό κολλέγιο καρδιολογίας ( ACC ) και η Αμeρικανική καρδιολογική eταιρία ( AHA ), από κοινού δημοσιeύουν κατeυθυντήριeς οδηγίeς για την αντιμeτώπιση των οξέων στeφανιαίων συνδρόμων. Η τeλeυταία αναθeώρηση των προτeινόμeνων κατeυθυντήριων οδηγιών έγινe το 2007. Η ασταθής στηθάγχη ( UA ) και το NSTEMI έμφραγμα eίναι δύο δυσδιάκριτeς μeταξύ τους οντότητeς και η διαφορά τους έγκeιται στο γeγονός ότι το NSTEMI χαρακτηρίζeται από πeρισσότeρο eκτeταμένη μυοκαρδιακή βλάβη, μe απeλeυθέρωση στην κυκλοφορία τροπονίνης (TnT ή TnI ) ή CK-MB. Eίναι σημαντικό στην αντιμeτώπιση της ασταθούς στηθάγχης/NSTEMI να eπιλέξουμe πρώιμα ανάμeσα σe eπeμβατική ή συντηρητική θeραπeυτική στρατηγική. Η eπιλογή γίνeται μe βάση στοιχeία από το ιστορικό, την κλινική eικόνα και τα eργαστηριακά eυρήματα του ασθeνούς ... (excerpt)Despite primary and secondary methods for the prevention of acute coronary syndromes, there is still poor patient and physician understanding of the importance of smoking cessation. Cardiovascular risk decreases significantly after smoking cessation, however, there is a paucity of counseling programs regarding this issue after hospitalization. Such programs have proved to be cost effective and should be provided as standard care.

Well-Functioning Double-Orifice Mitral Valve in a Young Woman with Marfan-Like Habitus and Atrial Tachycardia

50% of the cases DOMV functions well, while in the other 50% it can be stenotic or regurgitant. The DOMV is often associated with other congenital cardiac anomalies [2] . A 26-year-old woman was admitted because of paroxysmal atrial tachycardia for the past 5 years. The patient also had a Marfan-like habitus. Heart auscultation revealed no signifi cant murmurs or gallops. Transthoracic echocardiography revealed a mitral valve with two anatomically distinct Double-orifi ce mitral valve (DOMV) results from abnormal fusion of the embryonic endocardial cushions [1] . Patients with this anomaly may have two equal orifi ces (central or bridge type, 15% of patients) or one large mitral orifi ce and a smaller vestigial one (eccentric or hole type, approximately 85% of all patients). A third, rare type the so-called duplicated mitral valve which has two mitral annuli and valves, each with its own set of leafl ets and subvalvular apparatus, has also been described. In Received: January 6, 2005 Accepted after revision: March 15, 2005 Published online: September 2, 2005