Long-term prognostic value of contemporary stress echocardiography in patients with suspected or known coronary artery disease: systematic review and meta-analysis.

Background: Long-term outcome of contemporary stress echocardiography has not been systematically assessed.

Objective: To evaluate the association between results of stress echocardiography and patients' outcomes with suspected coronary artery disease using randomised controlled trials.

Methods: Multiple electronic databases were searched for studies evaluating long-term outcome (>12 months) of stress echocardiography in patients suspected of coronary artery disease since year 2000.

The role of cardiac magnetic resonance imaging in the assessment of heart failure with preserved ejection fraction.

Heart failure (HF) is a major cause of morbidity and mortality worldwide. Current classifications of HF categorize patients with a left ventricular ejection fraction of 50% or greater as HF with preserved ejection fraction or HFpEF. Echocardiography is the first line imaging modality in assessing diastolic function given its practicality, low cost and the utilization of Doppler imaging.

Fibroelastoma in an unusual location: a rare cause of multiple cerebrovascular events.

Unlabelled: Fibroelastomas are rare, primary cardiac tumours with a predilection for valvular endothelium and a propensity to embolise. We present the case of a 72-year-old male with multiple cerebrovascular events (CVA) despite oral anticoagulation. Transoesophageal echocardiography (TOE) revealed a small highly mobile left atrial mass with frond-like projections attached by a stalk to the orifice of the LAA.

Separation anxiety: Extreme dehiscence of a mitral annuloplasty ring.

We report a patient admitted with acute pulmonary edema 3 months after mitral valve repair, with no history of inter-current febrile illness. Transesophageal echocardiography (TEE) demonstrated severe mitral regurgitation (MR) and an abnormally positioned annuloplasty ring, suggestive of dehiscence. The extreme extent of ring dehiscence was visualized on 3-dimensional TEE (3D), with near-complete separation of the ring.

Correction to: does stress perfusion imaging improve the diagnostic accuracy of late gadolinium enhanced cardiac magnetic resonance for establishing the etiology of heart failure?

Following publication of the original article [1], the author reported his name has erroneously spelled as Abishek Shetye. The correct name is Abhishek Shetye.

Haemodynamic effects of pharmacologic stress with adenosine in patients with left ventricular systolic dysfunction.

Background: In patients with heart failure, downregulation of adenosine receptor gene expression and impaired adenosine-related signal transduction may result in a diminished response to adenosine. This may have implications for cardiac stress testing. We evaluated the haemodynamic response to intravenous adenosine in patients with left ventricular systolic dysfunction (LVSD) undergoing stress cardiovascular magnetic resonance imaging (CMR).

Does stress perfusion imaging improve the diagnostic accuracy of late gadolinium enhanced cardiac magnetic resonance for establishing the etiology of heart failure?

Background: Late gadolinium enhanced cardiovascular magnetic resonance (LGE-CMR) has excellent specificity, sensitivity and diagnostic accuracy for differentiating between ischemic cardiomyopathy (ICM) and non-ischemic dilated cardiomyopathy (NICM). CMR first-pass myocardial perfusion imaging (perfusion-CMR) may also play role in distinguishing heart failure of ischemic and non-ischemic origins, although the utility of additional of stress perfusion imaging in such patients is unclear. The aim of this retrospective study was to assess whether the addition of adenosine stress perfusion imaging to LGE-CMR is of incremental value for differentiating ICM and NICM in patients with severe left ventricular systolic dysfunction (LVSD) of uncertain etiology.

Comparison of exercise testing and CMR measured myocardial perfusion reserve for predicting outcome in asymptomatic aortic stenosis: the PRognostic Importance of MIcrovascular Dysfunction in Aortic Stenosis (PRIMID AS) Study.

Aims: To assess cardiovascular magnetic resonance (CMR) measured myocardial perfusion reserve (MPR) and exercise testing in asymptomatic patients with moderate-severe AS.

Methods And Results: Multi-centre, prospective, observational study, with blinded analysis of CMR data. Patients underwent adenosine stress CMR, symptom-limited exercise testing (ETT) and echocardiography and were followed up for 12-30 months.

Differences in performance of five types of aortic valve prostheses: haemodynamic assessment by dobutamine stress echocardiography.

Background: In patients being considered for aortic valve replacement, there remains controversy over which design or tissue offers the best performance. We aimed to evaluate in a single study the haemodynamic performances of five different widely used aortic valve prostheses: stentless porcine xenograft (Elan), stentless bovine pericardium (Pericarbon Freedom), stented porcine xenograft (Aspire), stented bovine pericardium (More) and mechanical (Ultracor). We also compared them with normal aortic valves and stenosed valves of variable severity.

Tetrahydrobiopterin supplementation reduces atherosclerosis and vascular inflammation in apolipoprotein E-knockout mice.

BH4 (tetrahydrobiopterin) supplementation improves endothelial function in models of vascular disease by maintaining eNOS (endothelial nitric oxide synthase) coupling and NO (nitric oxide) bioavailability. However, the cellular mechanisms through which enhanced endothelial function leads to reduced atherosclerosis remain unclear. We have used a pharmaceutical BH4 formulation to investigate the effects of BH4 supplementation on atherosclerosis progression in ApoE-KO (apolipoprotein E-knockout) mice.

Dressler's syndrome demonstrated by late gadolinium enhancement cardiovascular magnetic resonance.

A 49-year old patient presented late with an anterolateral ST-elevation myocardial infarction and was treated with rescue angioplasty to an occluded left anterior descending artery. Her recovery was complicated by low-grade pyrexia and raised inflammatory markers. Cardiovascular magnetic resonance 5 weeks after the acute presentation showed transmural infarction and global late gadolinium enhancement of the pericardium in keeping with Dressler's syndrome.

Pivotal role for endothelial tetrahydrobiopterin in pulmonary hypertension.

Background: Pulmonary hypertension is a fatal disease characterized by vasoconstriction and vascular remodeling. Loss of endothelial nitric oxide bioavailability is implicated in pulmonary hypertension pathogenesis. Recent evidence suggests that the cofactor tetrahydrobiopterin (BH4) is an important regulator of nitric oxide synthase enzymatic function.

Augmented BH4 by gene transfer restores nitric oxide synthase function in hyperglycemic human endothelial cells.

Objective: Endothelial dysfunction in diabetes is characterized by decreased nitric oxide (NO) bioactivity and increased superoxide (SO) production. Reduced levels of tetrahydrobiopterin (BH4), an essential cofactor of endothelial NO synthase (eNOS), appear to be associated with eNOS enzymatic uncoupling. We sought to investigate whether augmented BH4 biosynthesis in hyperglycemic human aortic endothelial cells (HAEC) by adenovirus-mediated gene transfer of GTP cyclohydrolase I (GTPCH, the rate-limiting enzyme for the de novo BH4 synthesis), would be sufficient to rescue eNOS activity and dimerization.

Congenic mapping and genotyping of the tetrahydrobiopterin-deficient hph-1 mouse.

The hph-1 ENU-mutant mouse provides a model of tetrahydrobiopterin deficiency for studying hyperphenylalaninaemia, dopa-response dystonia, and vascular dysfunction. We have successively localized the hph-1 mutation to a congenic interval of 1.6-2.

EPR quantification of vascular nitric oxide production in genetically modified mouse models.

With increasing use of genetically modified mice to study endothelial nitric oxide (NO) biology, methods for reliable quantification of vascular NO production by mouse tissues are crucial. We describe a technique based on electron paramagnetic resonance (EPR) spectroscopy, using colloid iron (II) diethyldithiocarbamate [Fe(DETC)2], to trap NO. A signal was seen from C57BL/6 mice aortas incubated with Fe(DETC)2, that increased 4.

Increased endothelial tetrahydrobiopterin synthesis by targeted transgenic GTP-cyclohydrolase I overexpression reduces endothelial dysfunction and atherosclerosis in ApoE-knockout mice.

Objective: Increased production of reactive oxygen species and loss of endothelial nitric oxide (NO) bioactivity are key features of vascular disease states such as atherosclerosis. Tetrahydrobiopterin (BH4) is a required cofactor for NO synthesis by endothelial nitric oxide synthase (eNOS); pharmacologic studies suggest that reduced BH4 availability may be an important mediator of endothelial dysfunction in atherosclerosis. We aimed to investigate the importance of endothelial BH4 availability in atherosclerosis using a transgenic mouse model with endothelial-targeted overexpression of the rate-limiting enzyme in BH4 synthesis, GTP-cyclohydrolase I (GTPCH).

Tetrahydrobiopterin-dependent preservation of nitric oxide-mediated endothelial function in diabetes by targeted transgenic GTP-cyclohydrolase I overexpression.

Increased production of reactive oxygen species and loss of endothelial NO bioactivity are key features of vascular disease states such as diabetes mellitus. Tetrahydrobiopterin (BH4) is a required cofactor for eNOS activity; pharmacologic studies suggest that BH4 may mediate some of the adverse effects of diabetes on eNOS function. We have now investigated the importance and mechanisms of BH4 availability in vivo using a novel transgenic mouse model with endothelial-targeted overexpression of the rate-limiting enzyme in BH4 synthesis, guanosine triphosphate-cyclohydrolase I (GTPCH).