Selective anti-scatter grid removal during coronary angiography and PCI: a simple and safe technique for radiation reduction.

Objectives The aim of this study was to quantify the radiation dose reduction during coronary angiography and percutaneous coronary intervention (PCI) through removal of the anti-scatter grid (ASG), and to assess its impact on image quality in adult patients with a low body mass index (BMI). Methods A phantom with different thicknesses of acrylic was used with a Westmead Test Object to simulate patient sizes and assess image quality. 129 low BMI patients underwent coronary angiography or PCI with or without the ASG in situ.

Real-time colour pictorial radiation monitoring during coronary angiography: effect on patient peak skin and total dose during coronary angiography.

Aims: The aim of this study was to evaluate whether a real-time (RT) colour pictorial radiation dose monitoring system reduces patient skin and total radiation dose during coronary angiography and intervention.

Methods And Results: Patient demographics, procedural variables and radiation parameters were recorded before and after institution of the RT skin dose recording system. Peak skin dose as well as traditionally available measures of procedural radiation dose were compared.

Grade 3 ischemia on the admission electrocardiogram is associated with severe microvascular injury on cardiac magnetic resonance imaging after ST elevation myocardial infarction.

Background: Grade 3 ischemia during ST elevation myocardial infarction (STEMI) is defined as ST elevation with distortion of the terminal portion of the QRS on electrocardiogram (ECG). The aim of this study was to evaluate the effect of ischemic grade on cardiac magnetic resonance (CMR) imaging infarct characteristics such as infarct size, microvascular obstruction (MVO), intramyocardial hemorrhage (IMH), and myocardial salvage.

Methods: Patients with STEMI treated with primary percutaneous coronary intervention had a 12-lead ECG on presentation for analysis of ischemic grade.

Dynamic Changes in ST Segment Resolution After Myocardial Infarction and the Association with Microvascular Injury on Cardiac Magnetic Resonance Imaging.

Background: persistent ST elevation after reperfused ST elevation myocardial infarction (STEMI) is believed to be related to poor microvascular perfusion. Cardiac magnetic resonance imaging (CMR) can evaluate microvascular obstruction (MVO) and intramyocardial haemorrhage (IMH) both of which represent severe microvascular damage, have independent prognostic value and are dynamic and evolving over the first 48hours after reperfusion. The aim of this study was to assess whether the development of MVO or IMH has an impact upon ST segment resolution.

Serum thromboxane B2 compared to five other platelet function tests for the evaluation of aspirin effect in stable cardiovascular disease.

Background: To assess the role of serum thromboxane B(2) (TXB(2)) measurements and the correlation between platelet function studies, in patients with stable cardiovascular disease on aspirin or clopidogrel.

Methods: 76 patients (47 on aspirin, 16 clopidogrel, 13 both) underwent assessment of TXB(2), whole blood aggregometry (WBA) after stimulation with (i) arachidonic acid (0.5mM), (ii) ADP (5 microM), (iii) collagen (1 and 5 microg/ml), PFA-100, and Cone and Plate Analyzer.

Multivessel coronary-ventricular fistulae and ischaemia on cardiac MRI.

Multivessel coronary ventricular fistulae is a rare coronary anomaly whose origin is believed to be from an arterioluminal or arteriosinusoidal connection with the ventricle. The clinical and haemodynamic significance of these fistulae have been a source of controversy despite varying methods of evaluation. A 69 year old female with exertional dyspnoea, atypical chest pain and multivessel coronary to left ventricular fistulae underwent cardiac MRI with adenosine stress.

Radiation exposure during elective coronary angioplasty: the effect of flat-panel detection.

Background: Coronary angiography and angioplasty have to date been performed using digital angiography and fluoroscopic systems which incorporate an image intensifier (II). More recently flat-panel (FP) detectors have been introduced which are thought to improve spatial resolution. However, there is limited data on the effect of flat-panel detection on radiation exposure.

Myocardial release of nitric oxide during ischaemia and reperfusion: effects of L-arginine and hypercholesterolaemia.

Aims: Nitric oxide (NO) may modulate myocardial ischaemia/reperfusion (I/R) injury, but effects of hypercholesterolaemia on myocardial NO release during I/R are unknown.

Methods: A NO-specific carbon fibre electrode continuously measured coronary sinus [NO] during 60 min low-flow ischaemia (1 ml/min) and 60 min free reperfusion (I/R) in isolated rabbit hearts. Experimental groups (n=7 per group) were control, L-arginine supplement (200 microM), N-nitro-L-arginine methyl ester (L-NAME) treatment (8 microM) and hypercholesterolaemic.

Serial angiography in patients with acute coronary syndromes: effect of antithrombotic therapy on angiographic lesion severity.

Background: Patients presenting with acute coronary syndromes (ACS) commonly have a responsible culprit coronary lesion. There is limited data on the natural history of this culprit lesion in the short term and whether there is a change in morphology of this lesion in the days following presentation. Furthermore, the effect of antithrombotic therapy on this process is unknown.

Angioplasty facilitated permanent pacing in de novo superior vena cava obstruction.

The finding of complete occlusion of the superior venal cava during the performance of cardiac pacing is rare. We report a case where performance of angioplasty aided the successful completion of permanent pacemaker implantation.

Proteomics of ischemia/reperfusion injury in rabbit myocardium reveals alterations to proteins of essential functional systems.

Brief periods of myocardial ischemia prior to timely reperfusion result in prolonged, yet reversible, contractile dysfunction of the myocardium, or "myocardial stunning". It has been hypothesized that the delayed recovery of contractile function in stunned myocardium reflects damage to one or a few key sarcomeric proteins. However, damage to such proteins does not explain observed physiological alterations to myocardial oxygen consumption and ATP requirements observed following myocardial stunning, and therefore the impact of alterations to additional functional groups is unresolved.

New bifurcation stenting technique: shunt stenting.

The optimal treatment of bifurcation lesions remains controversial. We describe a new technique we term shunt stenting. This technique incorporates both the new technology of drug-eluting stents and a novel procedure for optimizing the ostial side branch stent positioning.

Disassembly of a rotablator: getting out of a trap.

The rotablator burr rarely becomes trapped within calcified lesions. Manual traction can be ineffective and dangerous. We report a case that illustrates a novel technique involving use of a percutaneous snare in conjunction with partial disassembly of the rotablator device to remove a trapped burr without need for open surgical intervention.

Duration of ischaemia determines matrix metalloproteinase-2 activation in the reperfused rabbit heart.

It has been hypothesised that activation of matrix metalloproteinase-2 (MMP-2) contributes to reversible myocardial dysfunction (stunning) following short-term ischaemia and reperfusion. Gelatin zymography was used to measure release of both pro-MMP-2 (72 kDa) and MMP-2 (62 kDa), into the coronary effluent from isolated, perfused rabbit hearts during 90 min aerobic perfusion (control), or low-flow ischaemia (15 or 60 min at 1 mL/min), followed by 60 min reperfusion. In controls, pro-MMP-2 was detected in the coronary effluent throughout the first 30 min of aerobic perfusion, but MMP-2 was not detected.

Effect of treatment on ventricular function and troponin I proteolysis in reperfused myocardium.

Effects of ischemia time and treatment interventions upon troponin I (TnI) proteolysis and function of reperfused myocardium were examined in isolated, perfused rabbit hearts. Hearts were randomized to 90 min aerobic perfusion, 15 min low-flow (1 ml/min) ischemia (I) and 60 min reperfusion (R) or 60 min low-flow I and 60 min R. Hearts subject to 60 min I and 60 min R received either no treatment, l -arginine treatment, or treatment with oxygen free radical (OFR) scavengers (mercapto-proponyl-glycine, catalase and superoxide dismutase).