Right ventricular responses to CPAP therapy in obstructive sleep apnea: CMR analysis of the MOSAIC randomized trial.

Effects of continuous positive airway pressure (CPAP) on right ventricular (RV) function in patients with untreated mild-to-moderate obstructive sleep apnea (OSA) are unclear. In this exploratory analysis of cardiac magnetic resonance (CMR)-derived indices of RV function in patients with minimally symptomatic OSA from the MOSAIC randomized control trial we found no effect of CPAP on RV CMR parameters. In those with lower RV ejection fraction and higher RV end-diastolic volume (EDV) at baseline, CPAP treatment appeared to improve RV function with a significant reduction in both RV EDV and RV end-systolic volume although between-group effects were not observed.

Effect of CPAP on Cardiac Function in Minimally Symptomatic Patients with OSA: Results from a Subset of the MOSAIC Randomized Trial.

Study Objectives: Minimally symptomatic obstructive sleep apnea (OSA) is highly prevalent, and the effects of continuous positive airway pressure (CPAP) on myocardial function in these patients are unknown. The MOSAIC randomized, controlled trial of CPAP for minimally symptomatic OSA assessed the effect of CPAP on myocardial function in a subset of patients.

Methods: Two centers taking part in the MOSAIC trial randomized 238 patients in parallel to 6 months of CPAP (120) or standard care (118).

Atherosclerosis and arterial stiffness in obstructive sleep apnea--a cardiovascular magnetic resonance study.

Objective: Obstructive sleep apnoea (OSA) has been linked to cardiovascular risk factors, such as hypertension, and clinical cardiovascular endpoints. Our aim was to assess whether OSA is independently associated with atherosclerosis and vascular dysfunction as assessed by cardiovascular magnetic resonance (CMR).

Methods: 58 patients with OSA and 39 matched control subjects without OSA underwent CMR of the aorta and carotid arteries.

Plaque features associated with increased cerebral infarction after minor stroke and TIA: a prospective, case-control, 3-T carotid artery MR imaging study.

Objectives: The goal of this study was to determine whether a 3-T magnetic resonance imaging (MRI) protocol combining carotid atherosclerotic plaque and brain imaging can identify features of high-risk acutely symptomatic plaque that correlate with brain injury.

Background: It has previously been demonstrated that, in asymptomatic patients, MRI can identify features of carotid plaque that are associated with stroke, such as the presence of a large lipid core. We hypothesized that the early phase (<7 days) after a cerebrovascular event, when risk of recurrence is highest, may be associated with particular plaque characteristics that associate with cerebral injury.

Systemic and vascular oxidation limits the efficacy of oral tetrahydrobiopterin treatment in patients with coronary artery disease.

Background: The endothelial nitric oxide synthase cofactor tetrahydrobiopterin (BH4) plays a pivotal role in maintaining endothelial function in experimental vascular disease models and in humans. Augmentation of endogenous BH4 levels by oral BH4 treatment has been proposed as a potential therapeutic strategy in vascular disease states. We sought to determine the mechanisms relating exogenous BH4 to human vascular function and to determine oral BH4 pharmacokinetics in both plasma and vascular tissue in patients with coronary artery disease.

Multimodal cardiovascular magnetic resonance quantifies regional variation in vascular structure and function in patients with coronary artery disease: relationships with coronary disease severity.

Background: Cardiovascular magnetic resonance (CMR) of the vessel wall is highly reproducible and can evaluate both changes in plaque burden and composition. It can also measure aortic compliance and endothelial function in a single integrated examination. Previous studies have focused on patients with pre-identified carotid atheroma.

Impaired endothelial responses in apparently healthy young people associated with subclinical variation in blood pressure and cardiovascular phenotype.

Background: A phenomenon of endothelial impairment, independent of classical cardiovascular risk factors, has been observed in young people. We identified subjects with persistently reduced, or declining, endothelial function during adolescence and early adulthood, without apparent cardiovascular risk, and investigated the clinical relevance of this finding.

Methods: Endothelial vasomotor responses were assessed by brachial artery flow-mediated dilatation (FMD) at age 15 years in 47 subjects (22 males) who returned for a repeated measurement at age 25.

Short-term exposure to exogenous lipids in premature infants and long-term changes in aortic and cardiac function.

Objective: Intravenous lipid use is associated with an acute hyperlipidemia, but long-term consequences have not been studied. We investigated whether elevated lipids in humans during the critical period of preterm neonatal life have a long-term impact on aortic and myocardial function relevant to adult disease.

Methods And Results: We followed up 102 subjects born prematurely and now aged 23 to 28 years.

Elevated blood pressure in offspring born premature to hypertensive pregnancy: is endothelial dysfunction the underlying vascular mechanism?

Offspring born to mothers with hypertensive pregnancy have higher childhood blood pressure. We hypothesized this relates to prenatally programmed differences in the underlying vascular pathophysiology of the offspring and that these would be most apparent in those born preterm because of severe hypertension. We carried out a 20-year follow-up study of 71 subjects born preterm, 19 to a hypertensive pregnancy and 52 to a normotensive pregnancy.

Effects of high-dose modified-release nicotinic acid on atherosclerosis and vascular function: a randomized, placebo-controlled, magnetic resonance imaging study.

Objectives: Our aim was to determine the effects of high-dose (2 g) nicotinic acid (NA) on progression of atherosclerosis and measures of vascular function.

Background: NA raises high-density lipoprotein cholesterol (HDL-C) and reduces low-density lipoprotein cholesterol and is widely used as an adjunct to statin therapy in patients with coronary artery disease. Although changes in plasma lipoproteins suggest potential benefit, there is limited evidence of the effects of NA on disease progression when added to contemporary statin treatment.

Atherosclerosis regression.

Atherosclerosis follows the deposition, retention, and oxidative modification of lipoproteins, especially low-density lipoprotein (LDL) in the walls of large arteries. Uptake of oxidized LDL results in the formation of macrophage foam cells. Proliferation of vascular smooth muscle cells and secretion of extracellular matrix contribute "fibrous" components of the plaque, whereas ongoing accumulation of lipid and inflammatory cell debris forms the necrotic lipid core of the mature atherosclerotic plaque.