Effect of early changes in functional geometry of left ventricular contraction on the development of ventricular fibrillation during acute myocardial ischaemia. An experimental study.

Objective: The early appearance of ventricular fibrillation (VF) following acute myocardial infarction (MI) is associated with adrenergic effects and electrical interactions although some early "mechanical" changes may also occur. The aim of the present experimental study was to examine whether early changes in the functional geometry of left ventricular (LV) contraction may be associated with ventricular arrhythmias occurring during the first 120min of MI.

Methods: In 11 swine left anterior descending (LAD) coronary artery ligation was performed.

Effect of dobutamine on left ventricular functional geometry after acute myocardial infarction: experimental study.

Introduction: Acute myocardial infarction causes left ventricular (LV) remodelling, which forms the substrate for its early and late complications. The aim of this experimental study was to evaluate the acute changes in LV functional geometry after acute myocardial infarction using echocardiography and to investigate the effect of continuous intravenous dobutamine administration on those changes.

Methods: In 22 pigs acute myocardial infarction was induced by ligation of the anterior descending branch of the left coronary artery.

Intima-media thickness score from carotid and femoral arteries predicts the extent of coronary artery disease: intima-media thickness and CAD.

Objectives: In the present study we measured carotid and femoral intima-media thickness (IMT) by B-Mode ultrasonography, as well as angiographic extent and severity of coronary artery disease in patients referred for coronary arteriography, to assess the relation between individual IMT, scores incorporating IMT from the carotid and femoral arteries and the extent and severity of coronary artery disease.

Methods: Two hundred and two patients referred for elective coronary angiography underwent ultrasound imaging of both carotid and femoral arteries for IMT measurements. An IMT score was developed as the number of sites with abnormal IMT (range 0-8).

Arterial stiffness is increased in subjects with hypothyroidism.

Background: The association between hypothyroidism and increased vascular resistance, arterial wall thickening and endothelial dysfunction is well recognized. The aim of the present study was to examine if hypothyroid subjects have increased arterial stiffness, a risk factor for cardiovascular morbidity and mortality.

Methods: Sixty-five subjects (59 females and 6 males) with normal thyroid function or hypothyroidism of varying degree were investigated by radial artery applanation tonometry and pulse wave analysis, for evaluation of arterial stiffness.

Programmed ventricular stimulation in patients with idiopathic dilated cardiomyopathy and syncope receiving implantable cardioverter-defibrillators: a case series and a systematic review of the literature.

Background: The role of programmed ventricular stimulation (PVS) in patients with idiopathic dilated cardiomyopathy (DCM) and syncope receiving implantable cardioverter-defibrillators (ICD) remains controversial.

Methods And Results: Between 1994 and July 2002, 20 patients with DCM and syncope underwent PVS and ICD implantation at the Onassis Cardiac Surgery Center or the Alexandra General Hospital. At PVS 10 patients had inducible sustained monomorphic ventricular tachycardia (SMVT), 3 patients had inducible sustained polymorphic ventricular tachycardia or ventricular fibrillation, and 7 patients had no inducible arrhythmia.

Oral folic acid enhances endothelial function in patients with hypercholesterolaemia receiving statins.

Background: Folic acid therapy has been shown to improve endothelial function in patients with familial hypercholesterolaemia via a possible antioxidant mechanism. Data on the possible role of folic acid in hypercholesterolaemic patients receiving statins are lacking. In the present study we tested the hypothesis that folic acid supplementation improves endothelial function in patients with hypercholesterolaemia and treatment with statins.

New aspects on the role of blood pressure and arterial stiffness in mechanical assistance by intra-aortic balloon pump: in-vitro data and their application in clinical practice.

Despite the well-known beneficial effects of the intra-aortic balloon pump (IABP) generally, there are still some clinical conditions accompanied by IABP ineffectiveness. The aim of this study was the investigation of the independent effects of arterial stiffness and blood pressure on acute IABP effectiveness. For this purpose, a mock circulatory system and 20 patients with cardiogenic shock due to acute myocardial infarction, were employed.

Evaluation of myocardial performance index to predict mild rejection in cardiac transplantation.

Background: Early diagnosis of heart transplant rejection is mandatory, since even mild rejection can rapidly progress to more severe rejection. Noninvasive diagnosis of heart transplant rejection still remains a challenge.

Hypothesis: The purpose of the study was to determine a possible association between myocardial performance index (MPI) and biopsy score of the heart transplant.

Tamoxifen improves endothelial function and reduces carotid intima-media thickness in postmenopausal women.

Background: Tamoxifen is a selective estrogen-receptor modulator shown to improve several cardiovascular risk factors in postmenopausal women with breast cancer. In animal studies tamoxifen inhibits the progression of atherosclerosis. Although the presence of a history with tamoxifen treatment is related to a lower intima-media thickness (IMT) of the common carotid artery, data from controlled follow-up studies are lacking to support this observation.

Effect of ascorbic acid on forearm reactive hyperaemia in patients with hypercholesterolaemia.

Background: This study was designed to research the effect of hypercholesterolaemia and ascorbic acid on forearm blood flow (FBF) reactive hyperaemia (RH). Reactive hyperaemia seems to be at least partly endothelium-dependent. Endothelial dysfunction has been described in patients with hypercholesterolaemia, and has been reversed with ascorbic acid administration.

Pulse pressure and left ventricular diastolic dysfunction in hypertensive patients.

Background: Impaired left ventricular diastolic function is a common finding in essential hypertension.

Methods: In order to investigate possible relationships between flow velocity through the mitral valve (E/A; index of left ventricular diastolic function) and 24-hour blood pressure and heart rate variations, 198 patients with mild to moderate essential hypertension were studied by Doppler echocardiography and ambulatory blood pressure monitoring. They were divided according to age into group 1 (n = 88, age 40-54 years) and group 2 (n = 110, age 55-79 years).

Oral administration of ascorbic acid attenuates endothelial dysfunction after short-term cigarette smoking.

Short-term cigarette smoking is associated with persistent endothelial dysfunction. Data on the reversibility of this effect with per os antioxidants after short-term smoking are lacking. This study examines the effect of orally administered ascorbic acid on cigarette smoking-induced endothelial dysfunction.

Ascorbic acid does not improve endothelium-dependent flow-mediated dilatation of the brachial artery in patients with Raynaud's phenomenon secondary to systemic sclerosis.

Previous studies have shown that patients with Raynaud's phenomenon secondary to systemic sclerosis present abnormal endothelial function; the mechanisms responsible for the endothelial dysfunction are unknown but increased vascular oxidative stress could be a possible cause. The hypothesis that a potent water-soluble antioxidant can reverse endothelial dysfunction in these patients was tested in the present study. We examined 11 female patients with Raynaud's phenomenon secondary to systemic sclerosis and ten healthy control women by ultrasound imaging of the brachial artery to assess flow-mediated (endothelium-dependent) and nitrate-induced (endothelium-independent) vasodilatation.

Oral L-arginine improves endothelial dysfunction in patients with essential hypertension.

Background: L-Arginine is a nitric oxide precursor, which augments endothelium-dependent vasodilatation in hypercholesterolemic humans and animals. Endothelium-dependent vasodilation is attenuated in patients with hypertension; however the effects of oral L-arginine on endothelial function of the conduit arteries in patients with essential hypertension have not previously been investigated.

Methods: In a prospective randomized double blind trial, 35 patients with essential hypertension received either 6 g L-arginine (18 subjects) or placebo (17 subjects).

White-coat effect in normotension and hypertension.

Objectives: The difference between clinic and daytime ambulatory blood pressure is referred to as the white-coat effect. In this study, we investigated (i) the magnitude of the white-coat effect in subjects with different daytime ambulatory blood pressure levels, and (ii) the association of the white-coat effect with left ventricular mass.

Methods: A total of 1581 subjects underwent clinic blood pressure readings, 24-h ambulatory blood pressure monitoring and left ventricular echocardiographic assessment.

Arterial compliance is a main variable determining the effectiveness of intra-aortic balloon counterpulsation: quantitative data from an in vitro study.

Quantitative data concerning the effect of arterial compliance (AC) on the effectiveness of intra-aortic balloon counterpulsation (IABC) are lacking. The main objective of this study was to investigate the relationship between AC and IABC performance. For this purpose we constructed a Windkessel, lumped-element, hydraulic model of the systemic circulation.