Zenon Kyriakides

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Endothelin-1 and cyclic guanosine monophosphate (c-GMP) peripheral vein plasma levels increase during coronary angioplasty, but the reason for this increase has not been elucidated. The purpose of this study was to investigate whether these changes are related to myocardial ischaemia, or to mechanical artery injury induced during the procedure. Thirty-two(More)
AIM We examined whether there is a differential effect of endothelin-A antagonism on coronary artery compliance in type 2 diabetes mellitus compared to non-diabetic patients. PATIENT AND METHODS We examined 32 patients, 11 type 2 diabetes mellitus and 21 non-diabetic patients, with atherosclerotic epicardial arteries free of significant luminal stenoses.(More)
The effects of dual (ETA and ETB) endothelin receptor blockade on ventricular arrhythmogenesis during acute myocardial infarction are not well defined. We randomly allocated Wistar rats to bosentan (100 mg/kg daily, n=24), a dual endothelin receptor antagonist, or vehicle (n=23). After 7 days of treatment, myocardial infarction was induced by permanent(More)
OBJECTIVE To examine the contribution of endothelin type A (ET(A)) receptor stimulation by endogenously generated endothelin-1 (ET-1) to the maintenance of coronary vascular tone in humans. DESIGN Controlled clinical study. SETTING Tertiary cardiovascular referral centre. PATIENTS 14 subjects were studied, seven with normal coronary arteries and seven(More)
Mucopolysaccharidoses (MPS) are a heterogeneous group of lysosomal storage disorders, due to deficiency of glycosaminoglycans breakdown enzymes. MPS type III is also known as SanFilippo syndrome, which is further subdivided into four distinct forms--A, B, C and D--caused by different enzyme deficiencies, but with similar clinical characteristics. Cardiac(More)
STUDY OBJECTIVES Pacing-induced asynchrony may deteriorate left ventricular function; however, limited data exists in humans. The aim of our study was to compare left ventricular hemodynamics during short-term atrioventricular sequential pacing from the right ventricular apex and from the outflow tract of the right ventricle. DESIGN Three 5-min pacing(More)
Passive leg raising is commonly used for the initial treatment of hypovolemic shock. However, there are many reports which have pointed out that it does not produce significant autotransfusion effect. We tried to evaluate the effects of passive leg raising on the cardiovascular performance in coronary artery disease patients in stable condition. We studied(More)
BACKGROUND Myocardial ischemia and reperfusion are associated with increased production of endothelin (ET)-1. METHODS AND RESULTS We examined the effects of BQ-123, a selective ET(A) receptor antagonist, in 80 patients. All patients were randomly allocated to an intracoronary infusion of saline or BQ-123 (6 micromol/L over 20 minutes). The reference group(More)
BACKGROUND Few studies have addressed the impact of moderate unsupervised everyday physical activity in patients with chronic heart failure (CHF). DESIGN We investigated the effects of a 12-week walking programme as the sole exercise intervention on heart rate recovery (HRR), index of the autonomic system equilibrium, serum modulators of endothelial(More)
Endothelin (ET) exerts a tonic, stiffening effect on the common carotid artery in rats in vitro. This effect is mediated via the ET(A) receptor. The aim of this study was to examine the acute effects of ET(A) receptor antagonism on coronary artery compliance in humans. We examined 22 patients with stable angina after diagnostic coronary arteriography.(More)