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The cardiovascular benefits of omega‐3 polyunsaturated fatty acids (O3FA) remain a point of confusion in clinical medicine. Recently two large, randomised trials were published with discordant findings regarding the overall benefits of omega‐3 supplementation, resulting in unnecessary confusion and therapeutic nihilism. Epidemiological studies clearly show high intake of fish and measured O3FA (mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) in tissues are inversely associated with cardiovascular events and total mortality. These fatty acids are 'essential' and depend almost entirely on intake with very little production from within the body. The efficacy of supplementation depends on background tissue levels, in contradistinction to drug therapy. Insufficient dosing of omega‐3 supplementation using less than 1 g/day and lack of titration to target by failing to measure O3FA levels in the blood may explain these conflicting trial outcomes. We review the current evidence regarding O3FA supplementation and cardiovascular outcomes, describe possible reasons for the discrepant results in the literature including recent controversial data around the mineral oil comparator used in REDUCE‐IT and discuss the potential use of the omega‐3 index to guide management and optimise supplementation in those at greatest risk. [ABSTRACT FROM AUTHOR]

Atherosclerosis is the commonest cause of death in Australia. Cardiovascular (CV) risk calculators have an important role in preventative cardiology, although they are are strongly age-dependent and designed to identify individuals at high risk of an imminent event. The imprecision around "intermediate" or "low" risk generates therapeutic uncertainty, and a significant proportion of patients presenting with myocardial infarction come from these groups, often with no warning. This highlights a conundrum: "Low" risk does not mean "no" risk. A fresh approach may be required to address the clinical conundrum around CV preventative approaches in non-high-risk individuals. While probabilistic calculators do not measure atherosclerosis, calculation of Coronary Artery Calcium (CAC) scores by low-dose computed tomography (CT) can provide a snapshot of atherosclerotic burden. In intermediate-risk individuals, CAC is well-established as an aid to CV risk prediction. Although CAC scoring in low-risk asymptomatic people may be considered controversial, CAC has emerged as the single best predictor of CV events in asymptomatic individuals, independent of traditional risk factor calculators. Therefore, apart from the contribution of age and sex, the somewhat arbitrary distinction between "intermediate" and "low" CV risk using probabilistic calculators may need to be reconsidered. A zero CAC score has a very low future event rate and non-zero CAC scores are associated with a progressive, graded increase in risk as the CAC score rises. In this review, we examine the evidence for CAC screening in low-risk individuals, and propose more widespread use of CAC using simple new model intended to enhance established CV risk prediction equations. [ABSTRACT FROM AUTHOR]

Introduction: Coronary CT Angiography (CCTA) is a rapidly increasing technique for coronary imaging; however, it exposes patients to ionising radiation. We examined the impact of dose reduction techniques using ECG‐triggering, kVp/mAs reduction and high‐pitch modes on radiation exposure in a large Australian tertiary CCTA service. Methods: Data on acquisition modes and dose exposure were prospectively collected on all CCTA scans from November 2009 to March 2014 at an Australian tertiary care centre. A dose reduction algorithm was developed using published techniques and implemented with education of medical staff, radiographers and referrers. Associations of CCTA acquisition to radiation over time were analysed with multivariate regression. Specificity in positive CCTA was assessed by correlation with invasive coronary angiography. Results: 3333 CCTAs were analysed. Mean radiation dose decreased from 8.4 mSv to 5.3, 4.4, 3.7, 2.9 and 2.8 mSv (P < 0.001) per year. Patient characteristics were unchanged. Dose reduction strategies using ECG‐triggering, kVp/mAs reduction accounted for 91% of the decrease. High‐pitch scanning reduced dose by an additional 9%. Lower dose was independently related to lower kVp, heart rate, tube current modulation, BMI, prospective triggering and high‐pitch mode (P < 0.01). CCTA specificity remained unchanged despite dose reduction. Conclusion: Implementation of evidence‐based CCTA dose reduction algorithm and staff education programme resulted in a 67% reduction in radiation exposure, while maintaining diagnostic specificity. This approach is widely applicable to clinical practice for the performance of CCTA. [ABSTRACT FROM AUTHOR]

Abstract: Background: The left ventricular (LV) papillary muscles are important components of the mitral valve apparatus. Catheter ablation of ventricular arrhythmias from these sites is challenging. We aim to describe the association between LV papillary muscle ventricular arrhythmias (VAs) and mitral valve prolapse (MVP), and to determine the outcomes of ablation in these patients with a focus on those with MVP and cardiomyopathy. Methods: A total of 152 patients underwent 170 consecutive procedures for ablation of focal VAs. MVP and cardiomyopathy were diagnosed by echocardiography. Outcomes following ablation were assessed in three groups: (1) LV papillary muscle VAs versus other sites, (2) LV papillary muscle VAs by the presence of MVP, and (3) LV papillary muscle VAs in the setting of cardiomyopathy. Results: Nine of 23 (39%) patients undergoing ablation of LV papillary muscle VAs had MVP compared to none of 129 (0%) patients at other sites (P < 0.001). In the former group, acute procedural success was achieved in 60% and 80% of those with and without MVP, respectively (P = 0.28). Medium‐term outcomes were comparable (P = 0.75). In patients with cardiomyopathy, the median LV ejection fraction improved from 40% to 54% following ablation (P = 0.007). Conclusions: Although MVP is strongly associated with LV papillary muscle VAs, MVP does not adversely affect the acute or medium‐term outcomes of ablation. Systolic function can improve following ablation in patients with ectopy‐mediated cardiomyopathy due to papillary muscle VAs. [ABSTRACT FROM AUTHOR]

Objectives: Compare variability in flow measurements by phase contrast MRI, performed at different locations in the aorta and pulmonary artery (PA) using breath-held (BH) and free-breathing (FB) sequences.Methods: Fifty-seven patients with valvular heart disease, confirmed by echocardiography, were scanned using BH technique at 3 locations in the ascending aorta (SOV = sinus of Valsalva, STJ = sinotubular junction, ASC = ascending aorta at level of right pulmonary artery) and 2 locations in PA. Single FB measurement was obtained at STJ for aorta. Obtained metrics (SV = stroke volume, FV = forward volume, BV = backward volume, RF = regurgitant fraction) were evaluated separately for patients with aortic regurgitation (AR, n = 31) and mitral regurgitation (n = 26).Results: No difference was noted between the two measurements in the PA. Significant differences were noted in measured SV at different aortic locations. SV measurements obtained at ASC correlated best with the measurements obtained in the PA. Strongest correlation of AR was measured at the STJ.Conclusion: Measurements of flow volumes by phase contrast MRI differ depending on slice location. When using stroke volumes to calculate pulmonary to systemic blood flow ratio (Qp/Qs), ASC should be used. For quantifying aortic regurgitation, measurement should be obtained at STJ.Key Points: • Aortic regurgitation can be accurately measured by MRI. • Aortic regurgitation measurement by MRI varies according to the location where measured. • Aortic regurgitation can also be measured by MRI without breath hold. [ABSTRACT FROM AUTHOR]

Background: Coronary CT angiography (CCTA) has high sensitivity, with 3 recent randomized trials favorably comparing CCTA to standard-of-care. Comparison to exercise stress ECG (ExECG), the most available and least expensive standard-of-care worldwide, has not been systematically tested. Methods: CT-COMPARE was a randomized, single-center trial of low–intermediate risk chest pain subjects undergoing CCTA or ExECG after the first negative troponin. From March 2010 to April 2011, 562 patients randomized to either dual-source CCTA (n = 322) or ExECG (n = 240). Primary endpoints were diagnostic performance for ACS, and hospital cost at 30 days. Secondary endpoints were time-to-discharge, admission rates, and downstream resource utilization. Results: ACS occurred in 24 (4%) patients. ExECG had 213 negative studies and 27 (26%) positive studies for ACS with sensitivity of 83% [95% CI: 36, 99.6%], specificity of 91% [CI: 86, 94%], and ROC AUC of 0.87 [CI: 0.70, 1]. CCTA (> 50% stenosis considered positive) had 288 negative studies and 18/35 (51%) positive studies with a sensitivity of 100% [CI: 81.5, 100], specificity of 94% [CI: 91.2, 96.7%], and ROC of 0.97 [CI: 0.92, 1.0; p = 0.2]. Despite CCTA having higher odds of downstream testing (OR 2.0), 30 day per-patient cost was significantly lower for CCTA ($2193 vs $2704, p < 0.001). Length of stay for CCTA was significantly reduced (13.5 h [95% CI: 11.2–15.7], ExECG 19.7 h [95% CI: 17.4–22.1], p < 0.0005), which drove the reduction in cost. No patient had post-discharge cardiovascular events at 30 days. Conclusions: CCTA had improved diagnostic performance compared to ExECG, combined with 35% relative reduction in length-of-stay, and 20% reduction in hospital costs. These data lend further evidence that CCTA is useful as a first line assessment in emergency department chest pain. [ABSTRACT FROM AUTHOR]

Coronary CT angiography and coronary calcium scoring offer a new approach to the diagnosis of coronary artery disease (CAD). They hold significant promise in improving patient outcomes, through identification of atherosclerosis and improved risk assessment. Coronary calcium scoring has proven predictive value concerning the occurrence of future cardiovascular events and outperforms current risk evaluation methods such as the Framingham Risk Score. Coronary CT angiography allows visualisation of the coronary artery lumen, detection of stenoses as well as visualisation of both calcified and non-calcified plaque. The accuracy of coronary CT angiography to detect obstructive coronary artery disease has been established by numerous trials. In particular the negative predictive value of the test approaches 100% in low and intermediate risk groups. Outcomes data demonstrate significant prognostic ability of coronary CT angiography. Modern techniques allow substantial reduction of dose values and radiation exposure of coronary CT angiography has significantly fallen. Coronary CT angiography can be reliably performed with doses similar to the level of annual background radiation, and less than one-third of a Tc Sestamibi scan. Coronary CT angiography has been approved for Medicare reimbursement for specific indications when performed by accredited providers. High quality examinations, experience and careful patient selection and preparation are required to ensure optimal results of coronary CT angiography, and to guide clinical decisions. [ABSTRACT FROM AUTHOR]

Imaging of Scar in Patients with RV Origin Arrhythmias: CMR Versus EAM. Introduction: Assessment of late gadolinium enhancement (LGE) at cardiac magnetic resonance is often used to detect scar in patients with arrhythmias of right ventricular (RV) origin. Recently, electroanatomic mapping (EAM) has been shown to reliably detect scars corresponding to different cardiomyopathic substrates. We compared LGE with EAM for the detection of scar in patients with arrhythmias of RV origin. Methods and Results: Thirty-one patients with RV arrhythmias and biopsy-proven structural heart disease (18 ARVC and 13 myocarditis), and 5 with idiopathic RV outflow tract arrhythmias underwent LGE analysis and EAM with scar validation through EAM-guided endomyocardial biopsy. EAM scars were present in 23 (64%) patients (all with structural heart disease), whereas LGE was present only in 12 (33%). In 2 cases, EAM provided a false-positive diagnosis of a small scar in the basal perivalvular area. LGE correctly diagnosed EAM scar in 48% of patients, resulting in high positive (92%) but low negative (50%) predictive values. The distribution of LGE was significantly associated with the distribution of EAM scars (P < 0.001 in the free wall, P = 0.003 in the outflow tract, and P = 0.023 in the posterior/inferior wall). Presence of LGE reflected a higher extension of EAM scars (34.4 ± 16.5% vs 7.9 ± 10.1% of the RV area, P < 0.001). At receiver operating characteristic (ROC) analysis, an extension of scar ≥20% of the RV area was the best cut-off value to detect LGE (sensitivity 83%, specificity 92%). Of note, LGE missed 10 of 11 (91%) patients with EAM scars <20% of RV area. Conclusions: LGE is significantly less sensitive than EAM in identifying RV cardiomyopathic substrates. Absence of LGE does not rule out the presence of small scars, and EAM with biopsy should be considered to increase the diagnostic yield. (J Cardiovasc Electrophysiol, Vol. 22, pp. 1359-1366, December 2011) [ABSTRACT FROM AUTHOR]

Background: Gated Blood Pool Imaging (GBPI) has low inter-test variability compared to echocardiography, and is often used when accurate repeated measurements of left ventricular ejection fraction are required such as in the surveillance of post-transplant patients. The aim of this study was to determine if cardiac MRI (CMR) could replace Gated Blood Pool Imaging for annual assessment of left ventricular (LV) function in the surveillance of patients post-cardiac transplantation. Methods: Forty-nine patients at various stages of post-cardiac transplantation presenting for annual review underwent LV functional assessment with GBPI and CMR. LV ejection fractions (EF) obtained from the two methods were compared and limits of agreement determined. Results: The mean EF (plus and minus two standard deviations) was 58.3±18% for GBPI and 57.6±18% for CMR. The two methods were found to provide clinically equivalent results. Conclusions: Assessment of LVEF with CMR offers comparable values to GBPI in post-heart transplant patients. However, CMR also allows quantitative volumetric analysis of ventricular volumes and assessment of wall motion and valvular function. As is now accepted in native heart assessment, CMR should be considered the “gold standard” for post-transplant volumetric and functional evaluation. CMR offers information over-and-above traditional imaging modalities. [Copyright &y& Elsevier]

Background: The second-generation contrast agent Definity® (a perflutren microsphere) became available in Australia in mid-2007. We describe the introduction of contrast echocardiography into a high-volume quaternary teaching hospital, performing over 16,000 echocardiograms per year. Workflow protocols were developed for patient selection, contrast administration, and image acquisition and analysis. Methods: Data were prospectively collected for all contrast cases. Endocardial definition scores were derived by three independent observers before and after contrast administration, and statistically compared. Results: 161 patients received contrast in the first 12 months of the contrast program. There was statistically significant improvement in endocardial definition scores after contrast administration (p =0.0001), and reduction in inter-observer variability of wall motion assessment. A number of clinically significant findings (pseudoaneurysm, non-compaction, thrombus) were detected on contrast echo that were not apparent on standard 2D imaging. Adverse events were rare (0.6%) with no life-threatening events. Conclusions: The introduction of a second-generation contrast agent into clinical workflow in a hospital echocardiography department resulted in a statistically significant improvement in endocardial definition, and safely provided diagnostic imaging in cases which were otherwise non-diagnostic. Inter-observer variability was reduced, and diagnostic yield increased. These results reflect previously published data, and indicate that contrast echocardiography is feasible in Australian clinical practice. [Copyright &y& Elsevier]

This vignette illustrates a classic case of congenital mitral stenosis (Ruckman-VanPraagh type 1) presenting in adulthood and demonstrates the benefits of multimodality cardiac imaging prior to successful surgical intervention. [ABSTRACT FROM AUTHOR]

The article offers information related to CT coronary angiography (CTCA) as a first-line diagnostic test for chest pain in Australia. Topics include the advantages over stress testing in detecting CAD (coronary artery disease) and in identifying patients who require medical therapy; the use of preventive pharmacotherapies, such as statins and aspirin, through detection of nonobstructive CAD; and the ability to assess the burden, location and severity of coronary atherosclerotic plaque.

GadaCAD2 was 1 of 2 international, multicenter, prospective, Phase 3 clinical trials that led to U.S. Food and Drug Administration approval of gadobutrol to assess myocardial perfusion and late gadolinium enhancement (LGE) in adults with known or suspected coronary artery disease (CAD). A prespecified secondary objective was to determine if stress perfusion cardiovascular magnetic resonance (CMR) was noninferior to single-photon emission computed tomography (SPECT) for detecting significant CAD and for excluding significant CAD. Participants with known or suspected CAD underwent a research rest and stress perfusion CMR that was compared with a gated SPECT performed using standard clinical protocols. For CMR, adenosine or regadenoson served as vasodilators. The total dose of gadobutrol was 0.1 mmol/kg body weight. The standard of reference was a 70% stenosis defined by quantitative coronary angiography (QCA). A negative coronary computed tomography angiography could exclude CAD. Analysis was per patient. CMR, SPECT, and QCA were evaluated by independent central core lab readers blinded to clinical information. Participants were predominantly male (61.4% male; mean age 58.9 ± 10.2 years) and were recruited from the United States (75.0%), Australia (14.7%), Singapore (5.7%), and Canada (4.6%). The prevalence of significant CAD was 24.5% (n = 72 of 294). Stress perfusion CMR was statistically superior to gated SPECT for specificity (P = 0.002), area under the receiver operating characteristic curve (P < 0.001), accuracy (P = 0.003), positive predictive value (P < 0.001), and negative predictive value (P = 0.041). The sensitivity of CMR for a 70% QCA stenosis was noninferior and nonsuperior to gated SPECT. Vasodilator stress perfusion CMR, as performed with gadobutrol 0.1 mmol/kg body weight, had superior diagnostic accuracy for diagnosis and exclusion of significant CAD vs gated SPECT. [Display omitted] [ABSTRACT FROM AUTHOR]

The Australian Cardiovascular Alliance (ACvA), the Cardiac Society of Australia and New Zealand (CSANZ) and the National Heart Foundation of Australia (NHFA) recently joined forces to bring the cardiovascular and stroke community together to convene and document a national discussion and propose a national CVD Implementation and Policy agenda and action plan. This includes prevention and screening, acute care and secondary prevention. [ABSTRACT FROM AUTHOR]

An abstract of the paper "Late Gadolinium Enhancement Does Occur in the Tako-Tsubo Cardiomyopathy: A Quantitative Cardiovascular Magnetic Resonance Study," by Christian Hamilton-Craig and colleagues from the 2011 SCMR/Euro CMR Joint Scientific Sessions in Nice, France from February 3-6, 2011 is presented.

The article presents an abstract on a paper titled "Non-Tropical Endomyocardial Fibrosis by Cardiovascular Magnetic Resonance, Demonstrating the Value of CMR in Restrictive Cardiomyopathy," presented at the 2011 Society for Cardiovascular Magnetic Resonance (CMR)/Euro CMR Joint Scientific Sessions held in France.

The article presents an abstract on a paper titled "Quantification of Aortic Regurgitation and Stroke Volume by CMR - Variation Due to Slice Plane Position: It Matters Where You Measure!," presented at the 2011 Society for Cardiovascular Magnetic Resonance (CMR)/Euro CMR Joint Scientific Sessions held in France.

An abstract of the paper "Quantitative Blush Evaluator (QuBE) Accurately Quantifies Microvascular Dysfunction in Patients With ST-Elevation Myocardial Infarction; Comparison With Cardiovascular Magnetic Resonance," by Italo Porto and colleagues is presented.

Introduction: The purpose of this study was to obtain a range of normal measurements of the adult thoracic aorta and main pulmonary artery using cardiac MRI, and to assess agreement between measurements made on ECG-gated two-dimensional (2D) breath held steady-state-free precession (SSFP), and three-dimensional (3D) breath held SSFP image acquisitions.Methods: Forty-nine normal volunteers underwent cardiac MRI using a 1.5T system. Two independent examiners measured the ascending aorta, aortic arch, descending thoracic aorta and main pulmonary artery in pre-defined locations.Results: Overall, inter-observer agreement for all measurements was excellent. Close agreement was observed in aortic diameters obtained from the 2D and 3D SSFP methods in six of the nine aortic measurement sites. There was a tendency for the 3D measurements to be smaller than the 2D measurements but this was only significant at two sites, the aortic annulus, and the ascending aorta. There was a significance difference in aortic measurements between the left carotid artery (LC) and the left subclavian artery (LSC).Conclusion: Normal values for transverse diameters of the thoracic aorta and main pulmonary artery were established using 2D and 3D non-contrast MR sequences in healthy adults. Overall both inter-observer agreement, and agreement between 2D and 3D techniques was good. Mean diameter differences demonstrated at the aortic annulus, ascending aorta and aortic arch between LC and LSC although significant were less than one millimetre and unlikely to be important in clinical practice. [ABSTRACT FROM AUTHOR]

Computed tomography coronary angiography (CTCA) is a non-invasive diagnostic modality that provides a comprehensive anatomical assessment of the coronary arteries and coronary atherosclerosis, including plaque burden, composition and morphology. The past decade has witnessed an increase in the role of CTCA for evaluating patients with both stable and acute chest pain, and recent international guidelines have provided increasing support for a first line CTCA diagnostic strategy in select patients. CTCA offers some advantages over current functional tests in the detection of obstructive and non-obstructive coronary artery disease, as well as for ruling out obstructive coronary artery disease. Recent randomised trials have also shown that CTCA improves prognostication and guides the use of guideline-directed preventive therapies, leading to improved clinical outcomes. CTCA technology advances such as fractional flow reserve, plaque quantification and perivascular fat inflammation potentially allow for more personalised risk assessment and targeted therapies. Further studies evaluating demand, supply, and cost-effectiveness of CTCA for evaluating chest pain are required in Australia. This discussion paper revisits the evidence supporting the use of CTCA, provides an overview of its implications and limitations, and considers its potential role for chest pain evaluation pathways in Australia. [ABSTRACT FROM AUTHOR]

This position statement provides guidance to cardiologists and related specialists on the management of adult patients with elevated lipoprotein(a) [Lp(a)]. Elevated Lp(a) is an independent and causal risk factor for atherosclerotic cardiovascular disease (ASCVD) and calcific aortic valve disease (CAVD). While circulating Lp(a) levels are largely determined by ancestry, they are also influenced by ethnicity, hormones, renal function, and acute inflammatory events, such that measurement should be done after accounting for these factors. Further, circulating Lp(a) concentrations should be estimated using an apo(a)-isoform independent assay that employs appropriate calibrators and reports the results in molar units (nmol/L). Selective screening strategies of high-risk patients are recommended, but universal screening of the population is currently not advised. Testing for elevated Lp(a) is recommended in all patients with premature ASCVD and those considered to be at intermediate-to-high risk of ASCVD. Elevated Lp(a) should be employed to assess and stratify risk and to enable a decision on initiation or intensification of preventative treatments, such as cholesterol lowering therapy. In adult patients with elevated Lp(a) at intermediate-to-high risk of ASCVD, absolute risk should be reduced by addressing all modifiable behavioural, lifestyle, psychosocial and clinical risk factors, including maximising cholesterol-lowering with statin and ezetimibe and, where appropriate, PCSK9 inhibitors. Apheresis should be considered in patients with progressive ASCVD. New ribonucleic acid (RNA)-based therapies which directly lower Lp(a) are undergoing clinical trials. [ABSTRACT FROM AUTHOR]

Background: High-sensitivity cardiac troponin (hs-cTn) laboratory assays are used to rule out myocardial infarction (MI) on presentation, but prolonged result turn-around times can delay patient management. Our primary aim was to identify patients at low risk of index MI using a rapid, point of care (POC), whole blood hs-cTnI assay at presentation, with potential early patient discharge.Methods: Consecutive emergency department patients from two prospective, observational studies with suspected acute coronary syndrome were enrolled. A POC hs-cTnI assay (Atellica® VTLi) threshold using whole blood at presentation, that resulted in a negative predictive value (NPV) of ≥99.5% and sensitivity of ≥99% for index MI, was derived (Safe Emergency department dIscharGE rate [SEIGE]) and validated using plasma (Suspected acute myocardial infarction in Emergency [SAMIE]). Event adjudications were established using hs-cTnI assay results from routine clinical care. The primary outcome was MI at 30-days.Results: 1086 patients (8.1% MI) were enrolled in a US derivation cohort (SEIGE) and 1486 (5.5% MI) in an Australian validation cohort (SAMIE). A derivation whole blood POC hs-cTnI concentration of <4ng/L provided a sensitivity of 98.9% (93.8-100%) and NPV of 99.5% (95% CI: 97.2-100%) for ruling out MI. In the validation cohort, sensitivity was 98.8% (93.3-100%) and NPV was 99.8% (99.1-100%). 17.8% and 41.8%, respectively, were defined as low risk for discharge. 30-day adverse cardiac events were 0.1% (n=1) for SEIGE and 0.8% (n=5) for SAMIE.Conclusions: A point-of-care, whole blood hs-cTnI assay permits an accessible, rapid and safe exclusion of MI, and may expedite discharge from the emergency department. [ABSTRACT FROM AUTHOR]

Coronary artery disease (CAD) remains the leading cause of adult mortality globally. Targeting known modifiable risk factors has had substantial benefit, but there remains a need for new approaches. Improvements in invasive and noninvasive imaging techniques have enabled an increasing recognition of distinct quantitative phenotypes of coronary atherosclerosis that are prognostically relevant. There are marked differences in plaque phenotype, from the high-risk, lipid-rich, thin-capped atheroma to the low-risk, quiescent, eccentric, nonobstructive calcified plaque. Such distinct phenotypes reflect different pathophysiologic pathways and are associated with different risks for acute ischemic events. Noninvasive coronary imaging techniques, such as computed tomography, positron emission tomography, and coronary magnetic resonance imaging, have major potential to accelerate cardiovascular drug development, which has been affected by the high costs and protracted timelines of cardiovascular outcome trials. This may be achieved through enrichment of high-risk phenotypes with higher event rates or as primary end points of drug efficacy, at least in phase 2 trials, in a manner historically performed through intravascular coronary imaging studies. Herein, we provide a comprehensive review of the current technology available and its application in clinical trials, including implications for sample size requirements, as well as potential limitations. In its effort to accelerate drug development, the US Food and Drug Administration has approved surrogate end points for 120 conditions, but not for CAD. There are robust data showing the beneficial effects of drugs, including statins, on CAD progression and plaque stabilization in a manner that correlates with established clinical end points of mortality and major adverse cardiovascular events. This, together with a clear mechanistic rationale for using imaging as a surrogate CAD end point, makes it timely for CAD imaging end points to be considered. We discuss the importance of global consensus on these imaging end points and protocols and partnership with regulatory bodies to build a more informed, sustainable staged pathway for novel therapies. [ABSTRACT FROM AUTHOR]

Background: Recent data suggest that colchicine may reduce cardiovascular events among patients presenting with acute coronary syndromes. This sub-study of the Australian COPS trial aimed to assess whether colchicine affects health status outcomes.Methods: Health status was assessed at baseline and 12-months using the EuroQol-5 Dimension 5-level (EQ-5D-5L) score and the full 19-question Seattle Angina Questionnaire (SAQ). Data were available for 786 patients (388 randomized to colchicine, 398 to placebo).Results: Baseline characteristics were well matched between groups; mean age was 60.1 (SD 14.8) years, and 20 % were female. Baseline health status scores were impaired, and most parameters demonstrated significant improvement from baseline to 12-months (EQ-5D-5L Visual Analogue Score [VAS] 69.3 to 77.7; SAQ angina frequency score 83.0 to 95.3, both p < 0.001). No significant differences in adjusted mean score change among any of the EQ-5D-5L or SAQ dimensions were observed between treatment groups in either intention-to-treat or per-protocol analysis. There were borderline interactions in EQ-5D-5L scores for those with previous MI vs not, and in SAQ scores for those with obesity vs not. In categorical analysis using observed data, patients treated with colchicine were more likely to have clinically significant improvement in physical limitation score over the period (36 % improved vs. 28 %, p < 0.05). Baseline health status scores were not associated with the primary endpoint at 12 months.Conclusions: Treatment with colchicine did not appear to affect change in measures of health status following acute coronary syndromes, but it did lead to a greater likelihood of improvement in physical limitation scores.Trial Registration: ACTRN, ACTRN12615000861550. Registered 18/08/2015, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=368973. [ABSTRACT FROM AUTHOR]

Background: TEXTMEDS (Text Messages to Improve Medication Adherence and Secondary Prevention After Acute Coronary Syndrome) examined the effects of text message-delivered cardiac education and support on medication adherence after an acute coronary syndrome.Methods: TEXTMEDS was a single-blind, multicenter, randomized controlled trial of patients after acute coronary syndrome. The control group received usual care (secondary prevention as determined by the treating clinician); the intervention group also received multiple motivational and supportive weekly text messages on medications and healthy lifestyle with the opportunity for 2-way communication (text or telephone). The primary end point of self-reported medication adherence was the percentage of patients who were adherent, defined as >80% adherence to each of up to 5 indicated cardioprotective medications, at both 6 and 12 months.Results: A total of 1424 patients (mean age, 58 years [SD, 11]; 79% male) were randomized from 18 Australian public teaching hospitals. There was no significant difference in the primary end point of self-reported medication adherence between the intervention and control groups (relative risk, 0.93 [95% CI, 0.84-1.03]; P=0.15). There was no difference between intervention and control groups at 12 months in adherence to individual medications (aspirin, 96% vs 96%; β-blocker, 84% vs 84%; angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, 77% vs 80%; statin, 95% vs 95%; second antiplatelet, 84% vs 84% [all P>0.05]), systolic blood pressure (130 vs 129 mm Hg; P=0.26), low-density lipoprotein cholesterol (2.0 vs 1.9 mmol/L; P=0.34), smoking (P=0.59), or exercising regularly (71% vs 68%; P=0.52). There were small differences in lifestyle risk factors in favor of intervention on body mass index <25 kg/m2 (21% vs 18%; P=0.01), eating ≥5 servings per day of vegetables (9% vs 5%; P=0.03), and eating ≥2 servings per day of fruit (44% vs 39%; P=0.01).Conclusions: A text message-based program had no effect on medical adherence but small effects on lifestyle risk factors.Registration: URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=364448; Unique identifier: ANZCTR ACTRN12613000793718. [ABSTRACT FROM AUTHOR]

Computed tomographic coronary artery calcium scanning enables cardiovascular risk stratification; however, exposing patients to high radiation levels is an ongoing concern. New-generation computed tomographic systems use lower radiation doses than older systems do. To quantify comparative doses of radiation exposure, we prospectively acquired images from 220 patients with use of a 64-slice GE LightSpeed VCT scanner (control group, n=110) and a 256-slice GE Revolution scanner (study group, n=110). The groups were matched for age, sex, and body mass index; statistical analysis included t tests and linear regression. The mean dose-length product was 21% lower in the study group than in the control group (60.2 ± 27 vs 75.9 ± 22.6 mGy·cm; P <0.001) and also in each body mass index subgroup. Similarly, the mean effective radiation dose was 21% lower in the study group (0.84 ± 0.38 vs 1.06 ± 0.32 mSv) and lower in each weight subgroup. After adjustment for sex, women in the study group had a lower dose-length product (50.4 ± 23.4 vs 64.7 ± 27.6 mGy·cm) than men did and received a lower effective dose (0.7 ± 0.32 vs 0.9 ± 0.38 mSv) (P=0.009). As body mass index and waist circumference increased, so did doses for both scanners. Our study group was exposed to radiation doses lower than the previously determined standard of 1 mSv, even after adjustment for body mass index and waist circumference. In 256-slice scanning for coronary artery calcium, radiation doses are now similar to those in lung cancer screening and mammography. [ABSTRACT FROM AUTHOR]

Purpose: Left ventricular mechanical dispersion (LVMD) is a novel speckle tracking parameter for prognostic assessment of arrhythmic risk prediction. There is growing evidence to support its use in a variety of cardiomyopathic processes. There is paucity of data addressing any presence of inter‐vendor discrepancies for LVMD. The aim of this study was to assess inter‐vendor variability of LVMD in vendor specific software (VSS) and vendor independent software (VIS) in subjects with preserved and reduced left ventricular function. Methods: Fifty‐nine subjects (14 normal subjects and 45 subjects with cardiac disease) were recruited and 2D speckle tracking echocardiographic images were acquired on two different ultrasound machines (GE and Philips). LVMD was measured by two different VSS (EchoPac GE and QLAB Philips) and one VIS (TomTec Arena). Results: There was significant bias and wide limits of agreement (LOA) in the overall cohort observed between two different VSS (17.6 ms; LOA: ‐29.6 to 64.8; r:.47). There was acceptable bias and narrower LOA with good agreement for LVMD between images obtained on different vendors when performed on VIS (‐3.1 ms; LOA: ‐27.6 to 21.4; r:.75). QLAB LVMD was consistently higher than GE LVMD and TomTec LVMD in both preserved and reduced left ventricular function. LVMD measurements have high intra‐vendor reproducibility with excellent inter and intra‐observer agreement. Conclusions: There was acceptable bias and narrower LOA for LVMD assessment on a VIS. Inter‐vendor variability exists for LVMD assessment between VSS. Serial measurements of LVMD should be performed using a single vendor for consistent and reliable results. [ABSTRACT FROM AUTHOR]

Idiopathic VA are traditionally considered benign, although occasional patients develop an ectopy-mediated cardiomyopathy (EMC). It is unclear whether patients with idiopathic VA in the absence of left ventricular (LV) dysfunction harbor a subclinical cardiomyopathy. We aim to assess for cardiomyopathic substrate in patients with idiopathic ventricular arrhythmias (VA) using imaging and electrophysiologic markers of early fibrosis. Cardiac magnetic resonance (CMR) imaging and ventricular electroanatomic mapping was performed in 3 groups: patients undergoing ablation for idiopathic VA without (Group 1, n = 17) and with LV dysfunction (Group 2 [presumed EMC], n = 12) plus a control group undergoing ablation of supraventricular tachycardia (Group 3, n = 16). Global LV strain, T1 mapping and extended electrogram (EGM) characteristics were compared. Global strain was impaired in patients with presumed EMC (Group 2, p < 0.001). Native T1 times did not differ between groups, however patients in both idiopathic VA groups (Groups 1 and 2) had shorter post-contrast T1 times at 8 min compared to SVT controls (Group 3, p = 0.04). Similarly, the duration of the bipolar EGM was subtly prolonged in both Group 1 and 2 compared to Group 3 (p = 0.002). There were no between group differences in unipolar or bipolar voltage, the no. of bipolar EGM deflections or the maximal unipolar EGM dV/dt. Patients with idiopathic VAs and apparently structurally normal hearts may have subtle CMR and electrophysiologic changes similar in magnitude to that seen in frank presumed EMC, possibly suggestive of an occult cardiomyopathic process. • Idiopathic ventricular arrhythmias may be associated with a cardiomyopathic substrate • Post-contrast T1 changes (by cardiac MRI) may reflect interstitial fibrosis. • Prolonged electrogram duration may reflect conduction slowing. • These changes may be present even in the absence of left ventricular dysfunction. [ABSTRACT FROM AUTHOR]

Background: Coronary artery disease (CAD) remains a major public health problem in Australia and globally. A variety of imaging techniques allow for both anatomical and functional assessment of CAD and selection of the optimal investigation pathway is challenging. Cardiovascular magnetic resonance (CMR) is not widely used in Australia, partly due to perceived cost and lack of Federal Government reimbursement compared to the alternative techniques. The aim of this study was to estimate the cost-effectiveness of different diagnostic strategies in identifying significant CAD in patients with chest pain suggestive of angina using the evidence gathered in the Clinical Evaluation of Magnetic Resonance Imaging in Coronary Heart Disease 2 (CE-MARC trial), analysed from the Australian health care perspective.Methods: A decision analytic model coupled with three distinct Markov models allowed eight potential clinical investigation strategies to be considered; combinations of exercise electrocardiogram stress testing (EST), single-photon emission computed tomography (SPECT), stress CMR, and invasive coronary angiography (ICA). Costs were from the Australian health care system in Australian dollars, and outcomes were measured in terms of quality-adjusted life-years. Parameter estimates were derived from the CE-MARC and EUropean trial on Reduction Of cardiac events with Perindopril in patients with stable coronary Artery disease (EUROPA) trials, and from reviews of the published literature.Results: The most cost-effective diagnostic strategy, based on a cost-effectiveness threshold of $45,000 to $75,000 per QALY gained, was EST, followed by stress CMR if the EST was positive or inconclusive, followed by ICA if the stress CMR was positive or inconclusive; this held true in the base case and the majority of scenario analyses.Conclusions: This economic evaluation shows that an investigative strategy of stress CMR if EST is inconclusive or positive is the most cost-effective approach for diagnosing significant coronary disease in chest pain patients within the Australian health care system. [ABSTRACT FROM AUTHOR]

Background: Gadolinium-based contrast agents were not approved in the United States for detecting coronary artery disease (CAD) prior to the current studies.Objectives: The purpose of this study was to determine the sensitivity and specificity of gadobutrol for detection of CAD by assessing myocardial perfusion and late gadolinium enhancement (LGE) imaging.Methods: Two international, single-vendor, phase 3 clinical trials of near identical design, "GadaCAD1" and "GadaCAD2," were performed. Cardiovascular magnetic resonance (CMR) included gadobutrol-enhanced first-pass vasodilator stress and rest perfusion followed by LGE imaging. CAD was defined by quantitative coronary angiography (QCA) but computed tomography coronary angiography could exclude significant CAD.Results: Because the design and results for GadaCAD1 (n = 376) and GadaCAD2 (n = 388) were very similar, results were summarized as a fixed-effect meta-analysis (n = 764). The prevalence of CAD was 27.8% defined by a ≥70% QCA stenosis. For detection of a ≥70% QCA stenosis, the sensitivity of CMR was 78.9%, specificity was 86.8%, and area under the curve was 0.871. The sensitivity and specificity for multivessel CAD was 87.4% and 73.0%. For detection of a 50% QCA stenosis, sensitivity was 64.6% and specificity was 86.6%. The optimal threshold for detecting CAD was a ≥67% QCA stenosis in GadaCAD1 and ≥63% QCA stenosis in GadaCAD2.Conclusions: Vasodilator stress and rest myocardial perfusion CMR and LGE imaging had high diagnostic accuracy for CAD in 2 phase 3 clinical trials. These findings supported the U.S. Food and Drug Administration approval of gadobutrol-enhanced CMR (0.1 mmol/kg) to assess myocardial perfusion and LGE in adult patients with known or suspected CAD. [ABSTRACT FROM AUTHOR]

Background: The clinical use of cardiac magnetic resonance (CMR) in Australian heart failure (HF) patients has limited evidence. Aim: To examine how CMR, compared with routine echocardiography, affects the diagnosis and management of patients with HF. Methods: Single‐centre retrospective study of HF patients newly referred to the Advanced Heart Failure and Transplant unit at The Prince Charles Hospital, Brisbane. Between January 2010 and December 2014, all patients clinically referred for both CMR and echocardiography in the workup of HF were analysed. Imaging results, electronic records and medical charts were reviewed for final diagnosis and changes in clinical management. Results: A total of 114 new HF referrals was included. Evaluation of HF of uncertain aetiology (70%) was the most common indication for CMR. In 20% of cases, CMR led to a completely new diagnosis or diagnostic confirmation of suspicions raised by echocardiography. Clinical decision‐making was altered in 48%, with the greatest impact on decisions regarding revascularisation. Overall, CMR had a significant impact on 50% of patients. In a multivariable model, the only independent variable significantly associated with clinical impact was the presence/absence of late gadolinium enhancement (P < 0.001). Importantly, body mass index, echocardiography image quality and the presence of sinus rhythm did not show statistical significance in the multivariate analysis. Conclusion: CMR makes a substantial contribution to both the diagnosis and management of HF patients over and above standard echocardiography. This study provides evidence of its clinical utility in the HF population in Australia and supports the role of CMR in the routine assessment of this cohort. [ABSTRACT FROM AUTHOR]

Aim: Transthoracic echocardiography (TTE) is a fundamental investigation for the noninvasive assessment of pulmonary hemodynamics and right heart function. The aim of this study was to assess the correlation and agreement of Doppler calculation of right ventricular systolic pressure (RVSP) and pulmonary vascular resistance (PVR) using "chin" and "beard" measurements of tricuspid regurgitant velocity (TRVmax), with invasive pulmonary artery systolic pressure (PASP) and PVR. Methods: One hundred patients undergoing right heart catheterisation (RHC) and near simultaneous transthoracic echocardiography were studied. TRVmax was recorded for "chin" measurement (distinct peak TRVmax signal) and where available (63 patients), "beard" measurement (higher indistinct peak TRVmax signal). Results: Measurable TRV signal was obtained in 96 patients. Mean RVSPchin 54.7 ± 22.7 mm Hg and RVSPbeard 68.6 = 23 ± 26.3 mm Hg (P < .001). There was strong correlation between both RVSPchin and RVSPbeard with invasive PASP (Pearson's r = .9, R2 = 0.82, P < .001 -r = .88, R = .78, P < .001, respectively.). Bland-Altman analysis for RVSPchin and RVSPbeard showed a mean bias of -0.5 mm Hg (95% limits of agreement -21.4 to 20.5 mm Hg) and -10.7 (95% LOA -35.5 to 14.2 mm Hg), respectively. Receiver operator characteristics of TRVmax "chin" and "beard" for diagnosis of pulmonary hypertension was assessed with optimal cut-offs being 2.8 m/s (sensitivity 93%, specificity 87%) and 3.2 m/s (sensitivity 91%, specificity 82%), respectively. There was similar correlation between PVRchin and PVRbeard (r = .87, R2 = 0.75, P < .001 and r = .86, R2 = 0.74, P < .001, respectively). At higher PVR, there was overestimation of calculated PVR using PVRbeard. Conclusion: The accuracy of noninvasive measurement of right heart pressures is increased using the "chin" in estimation of both RVSP and PVR. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 39-year-old man who suffered from shortness of breath and whose echocardiography revealed severe RV dilation and tricuspid regurgitation.

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. Framingham Risk Score). Its use for risk stratification is confined to primary prevention of cardiovascular events, and can be considered as "individualised coronary risk scoring" for those not considered to be of high or low risk. Medical practitioners should carefully counsel patients prior to CAC. Coronary Artery Calcium Scoring should only be undertaken if an alteration in therapy including embarking on pharmacotherapy is being considered based on the test result. Patient Groups to Consider Coronary Calcium Scoring: Patient Groups in Whom Coronary Calcium Scoring Should Not be Considered: Coronary Artery Calcium Scoring is not recommended for patients who are: Interpretation of CAC CAC=0 A zero score confers a very low risk of death, <1% at 10 years. CAC=1-100 Low risk, <10% CAC=101-400 Intermediate risk, 10-20% CAC=101-400 & >75th centile. Moderately high risk, 15-20% CAC >400 High risk, >20% Management Recommendations Based on CAC Optimal diet and lifestyle measures are encouraged in all risk groups and form the basis of primary prevention strategies. Patients with moderately-high or high risk based on CAC score are recommended to receive preventative medical therapy such as aspirin and statins. The evidence for pharmacotherapy is less robust in patients at intermediate levels of CAC 100-400, with modest benefit for aspirin use; though statins may be reasonable if they are above 75th centile. Aspirin and statins are generally not recommended in patients with CAC <100. Repeat CAC Testing In patients with a CAC of 0, a repeat CAC may be considered in 5 years but not sooner. In patients with positive calcium score, routine re-scanning is not currently recommended. However, an annual increase in CAC of >15% or annual increase of CAC >100 units are predictive of future myocardial infarction and mortality. Cost Effectiveness of CAC Based Primary Prevention Recommendations: There is currently no data in Australia and New Zealand that CAC is cost-effective in informing primary prevention decisions. Given the cost of testing is currently borne entirely by the patient, discussion regarding the implications of CAC results should occur before CAC is recommended and undertaken. [ABSTRACT FROM AUTHOR]

This study aims to investigate the measurement of left ventricular flow propagation velocity, V p, using phase contrast magnetic resonance imaging and to assess the discrepancies resulting from inflow jet direction and individual left ventricular size. Three V p measuring techniques, namely non-adaptive (NA), adaptive positions (AP) and adaptive vectors (AV) method, were suggested and compared. We performed the comparison on nine healthy volunteers and nine post-infarct patients at four measurement positions, respectively, at one-third, one-half, two-thirds and the conventional 4 cm distances from the mitral valve leaflet into the left ventricle. We found that the V p measurement was affected by both the inflow jet direction and measurement positions. Both NA and AP methods overestimated V p, especially in dilated left ventricles, while the AV method showed the strongest correlation with the isovolumic relaxation myocardial strain rate (r = 0.53, p < 0.05). Using the AV method, notable difference in mean V p was also observed between healthy volunteers and post-infarct patients at positions of: one-half (81 ± 31 vs. 58 ± 25 cm/s), two-thirds (89 ± 32 vs. 45 ± 15 cm/s) and 4 cm (98 ± 23 vs. 47 ± 13 cm/s) distances. The use of AV method and measurement position at one-half distance was found to be the most suitable method for assessing diastolic dysfunction given varying left ventricular sizes and inflow jet directions. [ABSTRACT FROM AUTHOR]

Background: Transcatheter pulmonary valve implantation (TPVI) with the Melody® transcatheter pulmonary valve (TPV) has demonstrated good haemodynamic and clinical outcomes in the treatment of right ventricular outflow tract (RVOT) conduit dysfunction in patients with repaired congenital heart disease CHD. We present the first Australian single centre experience of patients treated with Melody TPV.Method: A prospective, observational registry was developed to monitor clinical and haemodynamic outcomes in patients with RVOT dysfunction treated with the Melody TPV (Medtronic Inc, Minneapolis, United States).Results: Seventeen patients underwent TPVI with Melody TPV at The Prince Charles Hospital between January 2009 and February 2016 with a median (range) age of 34 (R: 15-60). Fifteen (88%) were NYHA Class 2 dyspnoea and 11 (59%) had corrected Tetralogy of Fallot. Indication for TPVI was stenosis in eight (47%), regurgitation in two (12%) and mixed dysfunction in seven (41%). Device implantation was successful in all patients. Peak RVOT gradient was significantly reduced and there was no significant regurgitation post procedure. There was one (6%) major procedural adverse event and two (12%) major adverse events at last recorded follow-up. There were no patient deaths. Follow-up cardiac magnetic resonance imaging revealed a significant reduction in indexed right ventricular end diastolic volume.Conclusion: This study confirms the safety and effectiveness of TPVI with Melody TPV for RVOT dysfunction in repaired CHD. [ABSTRACT FROM AUTHOR]

Infarct extension, a process involving progressive extension of the infarct zone (IZ) into the normally perfused border zone (BZ), leads to continuous degradation of the myocardial function and adverse remodelling. Despite carrying a high risk of mortality, detailed understanding of the mechanisms leading to BZ hypoxia and infarct extension remains unexplored. In the present study, we developed a 3D truncated ellipsoidal left ventricular model incorporating realistic electromechanical properties and fibre orientation to examine the mechanical interaction among the remote, infarct and BZs in the presence of varying infarct transmural extent (TME). Localized highly abnormal systolic fibre stress was observed at the BZ, owing to the simultaneous presence of moderately increased stiffness and fibre strain at this region, caused by the mechanical tethering effect imposed by the overstretched IZ. Our simulations also demonstrated the greatest tethering effect and stress in BZ regions with fibre direction tangential to the BZ-remote zone boundary. This can be explained by the lower stiffness in the cross-fibre direction, which gave rise to a greater stretching of the IZ in this direction. The average fibre strain of the IZ, as well as the maximum stress in the sub-endocardial layer, increased steeply from 10% to 50% infarct TME, and slower thereafter. Based on our stress-strain loop analysis, we found impairment in the myocardial energy efficiency and elevated energy expenditure with increasing infarct TME, which we believe to place the BZ at further risk of hypoxia. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective: Cardiac magnetic resonance (CMR) has the potential to provide early detection of cardiac involvement in Fabry disease. We aimed to gain further insight into this by assessing a cohort of Fabry patients using CMR.Methods/results: Fifty genotype-positive Fabry subjects (age 45±2 years; 50% male) referred for CMR and 39 matched controls (age 40±2 years; 59% male) were recruited. Patients had a mean Mainz severity score index of 15±2 (range 0-46), reflecting an overall mild degree of disease severity. Compared with controls, Fabry subjects had a 34% greater left ventricular mass (LVM) index (82±5 vs 61±2 g/m(2), p=0.001) and had a significantly greater papillary muscle contribution to total LVM (13±1 vs 6±0.5%, p<0.001), even in the absence of left ventricular hypertrophy (LVH). Late gadolinium enhancement (LGE) was present in 15 Fabry subjects (9/21 males and 6/23 females). The most common site for LGE was the basal inferolateral wall (93%, 14/15). There was a positive association between LVM index and LGE. Despite this, there were two males and three females with no LVH that displayed LGE. Of Fabry subjects who were not on enzyme replacement therapy at enrolment (n=28), six were reclassified as having cardiac involvement (four LVH-negative/LGE-positive, one LVH-positive/LGE-positive and one LVH-positive/LGE-negative).Conclusions: CMR was able to detect cardiac involvement in 48% of this Fabry cohort, despite the overall mild disease phenotype of the cohort. Of those not on ERT, 21% were reclassified as having cardiac involvement allowing improved risk stratification and targeting of therapy. [ABSTRACT FROM AUTHOR]