Cardiac Society of Australia and New Zealand position statement executive summary: coronary artery calcium scoring.

Introduction This article summarises the Cardiac Society of Australia and New Zealand position statement on coronary artery calcium (CAC) scoring. CAC scoring is a non-invasive method for quantifying coronary artery calcification using computed tomography. It is a marker of atherosclerotic plaque burden and the strongest independent predictor of future myocardial infarction and mortality.

Cardiac Society of Australia and New Zealand Position Statement: Coronary Artery Calcium Scoring.

Coronary Artery Calcium Scoring (CAC) is a non-invasive quantitation of coronary artery calcification using computed tomography (CT). It is a marker of atherosclerotic plaque burden and an independent predictor of future myocardial infarction and mortality. Coronary Artery Calcium Scoring provides incremental risk information beyond traditional risk calculators (eg.

Non-diagnostic coronary artery calcification and stenosis: a correlation of coronary computed tomography angiography and invasive coronary angiography.

Background Heavy coronary artery calcification (CAC) impairs diagnostic accuracy of coronary computed tomography angiography (cCTA) and is considered to be a major limitation. Purpose To investigate the effect of non-evaluable CAC seen on cCTA on clinical decision-making by determining the degree of subsequent invasive testing and to assess the relationship between non-evaluable segments containing CAC and significant stenosis as seen in invasive coronary angiography (ICA). Material and Methods The study comprised of 356 patients who underwent cCTA and subsequent ICA within 2 months between 2005 and 2009.

Coronary atheroma composition and its association with segmental endothelial dysfunction in non-ST segment elevation myocardial infarction: novel insights with radiofrequency (iMAP) intravascular ultrasonography.

Little is known of the relationship between coronary atheroma composition and corresponding endothelial dysfunction. We tested the hypothesis that segmental epicardial vasoreactivity relates to atheroma composition in patients with non-ST segment elevation myocardial infarction (NSTEMI) in vivo. In 23 NSTEMI patients referred for coronary angiography, a non-culprit vessel underwent intracoronary salbutamol (0.

Left main coronary arterial endothelial function and heterogenous segmental epicardial vasomotor reactivity in vivo: novel insights with intravascular ultrasonography.

Aims: While the relationship between epicardial coronary vasomotor reactivity and cardiovascular events is well established, this observation has yet to be evaluated within the left main coronary artery (LMCA) in humans in vivo. Our aims were to test the endothelium-dependent vasomotor properties of the LMCA, and to compare these responses to downstream epicardial segments.

Methods And Results: Thirty patients referred for coronary angiography underwent intracoronary (IC) salbutamol provocation during intravascular ultrasound imaging within a non-critically diseased, left-sided conduit vessel.

Coronary artery wall shear stress is associated with endothelial dysfunction and expansive arterial remodelling in patients with coronary artery disease.

Aims: To investigate in vivo relationships between segmental wall shear stress (WSS), endothelium-dependent vasoreactivity and arterial remodelling.

Methods And Results: Twenty-four patients with minor angiographic coronary arterial disease (≤30% stenosis severity) underwent intracoronary (IC) salbutamol provocation during intravascular ultrasound (IVUS)-upon-Doppler guidewire imaging. Macrovascular response (change in segmental lumen volume [SLV] at baseline and following IC salbutamol), plaque burden (percent atheroma volume [PAV]), remodelling indices (RI), eccentricity indices (EI) and WSS were evaluated in 179 consecutive 5 mm coronary segments.

Coronary computed tomography angiography at 140 kV versus 120 kV: assessment of image quality and radiation exposure in overweight and moderately obese patients.

Background: Although a tube potential of 140 kV is available on most computed tomography (CT) scanners, its incremental diagnostic value versus 120 kV has been controversial.

Purpose: To retrospectively evaluate the image quality and radiation exposure of cardiac computed tomography angiography (CCTA) performed at 140 kV in comparison to CCTA at 120 kV in overweight and moderately obese patients.

Material And Methods: Eighty-eight patients who were referred for CCTA between January 2010 and May 2012 were included.

A novel analysis algorithm for potential quantitative assessment of myocardial computed tomography perfusion.

Rationale And Objectives: Cardiac computed tomography (CT) has emerged as a robust modality for imaging coronary stenosis and has recently been used to evaluate myocardial abnormalities such as ischemic perfusion defects and infarction. We developed a new image analysis algorithm for the semiautomatic and quantitative assessment of myocardial perfusion by CT.

Materials And Methods: The algorithm semiautomatically segments two-dimensional short-axis reformatted DICOM images of the left ventricle into regions of interest (ROIs) in accordance with American Heart Association (AHA) standards and is capable of creating nine further ROI subsegments.

Coronary endothelium-dependent vasoreactivity and atheroma volume in subjects with stable, minimal angiographic disease versus non-ST-segment-elevation myocardial infarction: an intravascular ultrasound study.

Background: Epicardial plaque burden and endothelial function are recognized predictors of coronary events. We aimed to investigate mechanistic relationships between atheroma volume and endothelial function in patients with non-ST-segment-elevation myocardial infarction (NSTEMI) using intravascular ultrasound.

Methods And Results: In coronary vessels of patients with near-normal or minimal angiographic disease (n=23) and NSTEMI (n=24), intravascular ultrasound-derived measures (percent atheroma volume), arterial remodeling index, and segmental lumen volumes were performed in contiguous 5-mm epicardial segments.

Relationship of aortic annular eccentricity and paravalvular regurgitation post transcatheter aortic valve implantation with CoreValve.

Background: Significant paravalvular aortic regurgitation (PAR) after transcatheter aortic valve implantation (TAVI) is associated with negative clinical consequences. We hypothesize that increased eccentricity of the aortic annulus is associated with greater PAR.

Methods: Patients with severe aortic stenosis underwent multidetector computed tomography (MDCT) before successful TAVI with the Medtronic CoreValve bioprosthesis.

Classification of coronary atherosclerotic plaques ex vivo with T1, T2, and ultrashort echo time CMR.

Objectives: This study sought to determine whether the classification of human coronary atherosclerotic plaques with T1, T2, and ultrashort echo time (UTE) cardiac magnetic resonance (CMR) would correlate well with atherosclerotic plaque classification by histology.

Background: CMR has been extensively used to classify carotid plaque, but its ability to characterize coronary plaque remains unknown. In addition, the detection of plaque calcification by CMR remains challenging.

Histopathological correlates of the napkin-ring sign plaque in coronary CT angiography.

Objective: The purpose of this study was to identify histologic characteristics of advanced coronary atherosclerotic plaques that are related with the detection of the napkin-ring sign (NRS) in coronary CT angiography (CCTA).

Methods: CCTA was performed in 7 human donor hearts. Histological slicing and stainings were performed in 1 mm increments of each major coronary artery.

Coronary computed tomography angiography during arrhythmia: Radiation dose reduction with prospectively ECG-triggered axial and retrospectively ECG-gated helical 128-slice dual-source CT.

Background: Arrhythmia during coronary computed tomography angiography (coronary CTA) acquisition increases the risk of nondiagnostic segments and high radiation exposure. An advanced arrhythmia rejection algorithm for prospectively electrocardiogram (ECG)-triggered axial scans using dual-source CT (DSCT) examinations has recently been reported.

Objective: We compared image quality and effective dose at DSCT examinations using prospectively ECG-triggered axial scanning with advanced arrhythmia rejection software (PT-AAR) versus retrospectively ECG-gated helical scanning with tube-current modulation (RG-TCM) during arrhythmia.

Intracoronary ECG ST-segment recovery during primary percutaneous intervention for ST-segment myocardial infarction: insights from a cardiac MRI study.

Background: ST-segment-resolution (STR) on surface electrocardiogram (ECG) is a good surrogate for myocardial reperfusion in patients with acute ST-segment-elevation-myocardial-infarction (STEMI). We sort to determine the optimal criteria of measuring STR on intracoronary-ECG (IC-ECG) for prediction of myocardial injury evaluated by cardiac MRI (CMR).

Methods: Measurements of IC-ECG ST-segments were performed at baseline, immediately after (early) and 15 min (late) after achieving TIMI-3 flow during primary-PCI.

Appropriate indications for computed tomography coronary angiography.

Computed tomography coronary angiography (CTCA) has been shown in multicentre trials to be reliable in ruling out significant coronary artery disease (CAD). It is used most appropriately in symptomatic patients with low to intermediate pretest probability of CAD. It should not be used in asymptomatic subjects, patients with known significant CAD or patients with a high pretest probability of CAD.

Aortic annulus dimension assessment by computed tomography for transcatheter aortic valve implantation: differences between systole and diastole.

Accurate assessment of aortic annular dimensions is essential for successful transcatheter aortic valve implantation (TAVI). Annular dimensions are conventionally measured in mid-systole by multidetector computed tomography (MDCT), echocardiography and angiography. Significant differences in systolic and diastolic aortic annular dimensions have been demonstrated in cohorts without aortic stenosis (AS), but it is unknown whether similar dynamic variation in annular dimensions exists in patients with severe calcific AS in whom aortic compliance is likely to be substantially reduced.

Diagnostic accuracy of adenosine stress cardiovascular magnetic resonance following acute ST-segment elevation myocardial infarction post primary angioplasty.

Background: Adenosine stress cardiovascular magnetic resonance (CMR) has been proven an effective tool in detection of reversible ischemia. Limited evidence is available regarding its accuracy in the setting of acute coronary syndromes, particularly in evaluating the significance of non-culprit vessel ischaemia. Adenosine stress CMR and recent advances in semi-quantitative image analysis may prove effective in this area.

Coronary β2-adrenoreceptors mediate endothelium-dependent vasoreactivity in humans: novel insights from an in vivo intravascular ultrasound study.

Aims: The interaction between coronary β(2)-adrenoreceptors and segmental plaque burden is complex and poorly understood in humans. We aimed to validate intracoronary (IC) salbutamol as a novel endothelium-dependent vasodilator utilizing intravascular ultrasound (IVUS), and thus assess relationships between coronary β(2)-adrenoreceptors, regional plaque burden and segmental endothelial function.

Methods And Results: In 29 patients with near-normal coronary angiograms, IVUS-upon-Doppler Flowire imaging protocols were performed.

Intracoronary ECG during primary percutaneous coronary intervention for ST-segment elevation myocardial infarction predicts microvascular obstruction and infarct size.

Introduction: Microvascular obstruction (MVO) following ST-segment elevation myocardial infarction (STEMI) is associated with larger infarct size and an increased mortality. Although angiographic predictors of MVO in primary percutaneous coronary intervention (primary-PCI) setting have been identified, an earlier and objective "in-lab" predictor may be beneficial, in order to potentially influence therapies administered during primary-PCI. We hypothesised that intracoronary-electrocardiogram (IC-ECG) is a simple, objective and accurate predictor of MVO evaluated by cardiac magnetic resonance (CMR) and is comparable to myocardial blush grade (MBG) and TIMI myocardial perfusion grade (TMPG).

In vivo non-invasive serial monitoring of FDG-PET progression and regression in a rabbit model of atherosclerosis.

We investigated the ability of fluorodeoxyglucose positron emission tomography (FDG PET) imaging to serially monitor macrophage content in a rabbit model of atherosclerosis. Atherosclerosis was induced in rabbits (n = 8) by a combination of atherogenic diet and balloon denudation of the aorta. At the end of nine months, the rabbits were randomized to a further six months of the same atherogenic diet (progression group) or normal diet (regression group).

Long-term performance of active-fixation pacing leads: a prospective study.

Background: Despite the increasingly widespread use of active-fixation leads, long-term clinical follow-up of pacing lead outcomes is lacking. The aim was to analyze pacing parameters over a 2-year follow-up. We performed a prospective observational study of consecutive new pacemaker implants using the 1488T St.