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The indication for cardiac pacing has been reliant on electrocardiography and the severity of bradycardia symptom correlation ([1][1]). Cardiovascular magnetic resonance (CMR) is routinely used in the assessment and prognostication of cardiac disease, but the clinical usefulness in patients with

Background Heart failure (HF) is characterized by altered myocardial substrate metabolism which can lead to myocardial triglyceride accumulation (steatosis) and lipotoxicity. However its role in mild HF with preserved ejection fraction (HFpEF) is uncertain. We measured myocardial triglyceride content (MTG) in HFpEF and assessed its relationships with diastolic function and exercise capacity. Methods Twenty seven HFpEF (clinical features of HF, left ventricular EF >50%, evidence of mild diastolic dysfunction and evidence of exercise limitation as assessed by cardiopulmonary exercise test) and 14 controls underwent 1H-cardiovascular magnetic resonance spectroscopy (1H-CMRS) to measure MTG (lipid/water, %), 31P-CMRS to measure myocardial energetics (phosphocreatine-to-adenosine triphosphate - PCr/ATP) and feature-tracking cardiovascular magnetic resonance (CMR) imaging for diastolic strain rate. Results When compared to controls, HFpEF had 2.3 fold higher in MTG (1.45 ± 0.25% vs. 0.64 ± 0.16%, p = 0.009) and reduced PCr/ATP (1.60 ± 0.09 vs. 2.00 ± 0.10, p = 0.005). HFpEF had significantly reduced diastolic strain rate and maximal oxygen consumption (VO2 max), which both correlated significantly with elevated MTG and reduced PCr/ATP. On multivariate analyses, MTG was independently associated with diastolic strain rate while diastolic strain rate was independently associated with VO2 max. Conclusions Myocardial steatosis is pronounced in mild HFpEF, and is independently associated with impaired diastolic strain rate which is itself related to exercise capacity. Steatosis may adversely affect exercise capacity by indirect effect occurring via impairment in diastolic function. As such, myocardial triglyceride may become a potential therapeutic target to treat the increasing number of patients with HFpEF.

Objectives This study sought to test the diagnostic performance of native T1 mapping in acute myocarditis compared with cardiac magnetic resonance (CMR) techniques such as dark-blood T2-weighted (T2W)-CMR, bright-blood T2W-CMR, and late gadolinium enhancement (LGE) imaging. Background The diagnosis of acute myocarditis on CMR often requires multiple techniques, including T2W, early gadolinium enhancement, and LGE imaging. Novel techniques such as T1 mapping and bright-blood T2W-CMR are also sensitive to changes in free water content. We hypothesized that these techniques can serve as new and potentially superior diagnostic criteria for myocarditis. Methods We investigated 50 patients with suspected acute myocarditis (age 42 ± 16 years; 22% women) and 45 controls (age 42 ± 14 years; 22% women). CMR at 1.5-T (median 3 days from presentation) included: 1) dark-blood T2W-CMR (short-tau inversion recovery); 2) bright-blood T2W-CMR (acquisition for cardiac unified T2 edema); 3) native T1 mapping (shortened modified look-locker inversion recovery); and 4) LGE. Image analysis included: 1) global T2 signal intensity ratio of myocardium compared with skeletal muscle; 2) myocardial T1 relaxation times; and 3) areas of LGE. Results Compared with controls, patients had significantly higher global T2 signal intensity ratios by dark-blood T2W-CMR (1.73 ± 0.27 vs. 1.56 ± 0.15, p Conclusions Native T1 mapping as a novel criterion for the detection of acute myocarditis showed excellent and superior diagnostic performance compared with T2W-CMR. It also has a higher sensitivity compared with T2W and LGE techniques, which may be especially useful in detecting subtle focal disease and when gadolinium contrast imaging is not feasible.

Background— Aortic stenosis (AS) leads to left ventricular (LV) hypertrophy and dysfunction. We hypothesized that cardiac steatosis is involved in the pathophysiology and also assessed whether it is reversible after aortic valve replacement. Methods and Results— Thirty-nine patients with severe AS (symptomatic=25, asymptomatic=14) with normal LV ejection fraction and no significant coronary artery disease and 20 age- and sex-matched healthy controls underwent cardiac 1H-magnetic resonance spectroscopy and imaging for the determination of steatosis (myocardial triglyceride content) and cardiac function, including circumferential strain (measured by magnetic resonance tagging). Strain was lower in both symptomatic and asymptomatic AS (−16.4±2.5% and −18.1±2.9%, respectively, versus controls −20.7±2.0%, both P P Conclusions— Pronounced myocardial steatosis is present in severe AS, regardless of symptoms, and is independently associated with the degree of LV strain impairment. Myocardial triglyceride content measured by magnetic resonance spectroscopy correlates with histological quantification. Steatosis and strain impairment are reversible after aortic valve replacement. Our findings suggest a novel pathophysiological mechanism in AS, myocardial steatosis, which may be amenable to treatment, thus potentially delaying onset of LV dysfunction.

Right ventricular strain assessment by feature tracking from cine images shows acceptable levels of agreement with echocardiography

Background: Acute myocarditis can be diagnosed on cardiovascular magnetic resonance (CMR) using multiple techniques, including late gadolinium enhancement (LGE) imaging, which requires contrast administration. Native T1-mapping is significantly more sensitive than LGE and conventional T2-weighted (T2W) imaging in detecting myocarditis. The aims of this study were to demonstrate how to display the non-ischemic patterns of injury and to quantify myocardial involvement in acute myocarditis without the need for contrast agents, using topographic T1-maps and incremental T1 thresholds. Methods. We studied 60 patients with suspected acute myocarditis (median 3 days from presentation) and 50 controls using CMR (1.5 T), including: (1) dark-blood T2W imaging; >(2) native T1-mapping (ShMOLLI); (3) LGE. Analysis included: (1) global myocardial T2 signal intensity (SI) ratio compared to skeletal muscle; (2) myocardial T1 times; (3) areas of injury by T2W, T1-mapping and LGE. Results: Compared to controls, patients had more edema (global myocardial T2 SI ratio 1.71 ± 0.27 vs.1.56 ± 0.15), higher mean myocardial T1 (1011 ± 64 ms vs. 946 ± 23 ms) and more areas of injury as detected by T2W (median 5% vs. 0%), T1 (median 32% vs. 0.7%) and LGE (median 11% vs. 0%); all p < 0.001. A threshold of T1 > 990 ms (sensitivity 90%, specificity 88%) detected significantly larger areas of involvement than T2W and LGE imaging in patients, and additional areas of injury when T2W and LGE were negative. T1-mapping significantly improved the diagnostic confidence in an additional 30% of cases when at least one of the conventional methods (T2W, LGE) failed to identify any areas of abnormality. Using incremental thresholds, T1-mapping can display the non-ischemic patterns of injury typical of myocarditis. Conclusion: Native T1-mapping can display the typical non-ischemic patterns in acute myocarditis, similar to LGE imaging but without the need for contrast agents. In addition, T1-mapping offers significant incremental diagnostic value, detecting additional areas of myocardial involvement beyond T2W and LGE imaging and identified extra cases when these conventional methods failed to identify abnormalities. In the future, it may be possible to perform gadolinium-free CMR using cine and T1-mapping for tissue characterization and may be particularly useful for patients in whom gadolinium contrast is contraindicated. © 2014 Ferreira et al.; licensee BioMed Central Ltd.

We thank Ellims et al for their query about the consistency of results from the T1 mapping literature on hypertrophic cardiomyopathy. The letter serves well to highlight an important issue: the fundamental differences between native (or precontrast) T1 mapping and postcontrast T1 mapping as distinct techniques. Native myocardial T1 increases with conditions involving an increase in free water content, whereas postcontrast T1 typically decreases. Results and correlations derived from studies using these different biomarkers should not be expected to demonstrate a direct relationship. Single-time-point postcontrast T1 constitutes a momentary snapshot of the transient effect of …

Background— Noncontrast magnetic resonance T1 mapping reflects a composite of both intra- and extracellular signal. We hypothesized that noncontrast T1 mapping can characterize the myocardium beyond that achieved by the well-established late gadolinium enhancement (LGE) technique (which detects focal fibrosis) in both hypertrophic (HCM) and dilated (DCM) cardiomyopathy, by detecting both diffuse and focal fibrosis. Methods and Results— Subjects underwent Cardiovascular Magnetic Resonance imaging at 3T (28 HCM, 18 DCM, and 12 normals). Matching short-axis slices were acquired for cine, T1 mapping, and LGE imaging (0.1 mmol/kg). Circumferential strain was measured in the midventricular slice, and 31 P magnetic resonance spectroscopy was acquired for the septum of the midventricular slice. Mean T1 relaxation time was increased in HCM and DCM (HCM 1209±28 ms, DCM 1225±42 ms, normal 1178±13 ms, P r =0.32, P P P P r =0.42, P r =0.56, P =0.04). Finally, there was also a statistically significant negative correlation between T1 values and phosphocreatine/adenosine triphosphate ratios ( r =−0.59, P Conclusions— In HCM and DCM, noncontrast T1 mapping detects underlying disease processes beyond those assessed by LGE in relatively low-risk individuals.

Human immunodeficiency virus (HIV) infection is considered a chronic, treatable disease, although treatment is associated with increased rates of coronary artery disease (CAD). We analyzed the utility of coronary CTA in the assessment of CAD among HIV patients and explored whether HIV patients are at greater risk of associated morbidity and mortality compared to HIV-negative controls.In a retrospective, single center cohort study 97 males without history of previous coronary artery disease who had undergone coronary CTA between 2011 and 2014 was analyzed, including 32 HIV positive patients and 65 matched HIV negative controls. Presence and composition of coronary plaque was determined by coronary CTA. Data on subsequent coronary events and coronary intervention was collected.Patients with HIV had higher rates of non-calcified plaque (0.8 ± 1.5 versus 0.3 ± 0.7, p = 0.03) compared to negative controls. At a median follow-up of 38 months, patients with HIV were at greater risk of non-ST elevation acute coronary syndrome (16% versus 3%, p 0.04), although there was no difference in the combined endpoint of all acute coronary syndromes (19% versus 6%, p = 0.08). Following baseline coronary TCA, there was a higher rate of coronary intervention in patients without HIV (mean time to event 9.9 ± 3.3 versus 20.6 ± 4.9 months, p 0.04).Patients with HIV more pronounces coronary atherosclerosis on coronary CTA and higher rates of non-ST elevation acute coronary syndromes compared to negative controls.

Background— Patients with treated HIV infection have clear survival benefits although with increased cardiac morbidity and mortality. Mechanisms of heart disease may be partly related to untreated chronic inflammation. Cardiovascular magnetic resonance imaging allows a comprehensive assessment of myocardial structure, function, and tissue characterization. We investigated, using cardiovascular magnetic resonance, subclinical inflammation and myocardial disease in asymptomatic HIV-infected individuals. Methods and Results— Myocardial structure and function were assessed using cardiovascular magnetic resonance at 1.5-T in treated HIV-infected individuals without known cardiovascular disease (n=103; mean age, 45±10 years) compared with healthy controls (n=92; mean age, 44±10 years). Assessments included left ventricular volumes, ejection fraction, strain, regional systolic, diastolic function, native T1 mapping, edema, and gadolinium enhancement. Compared with controls, subjects with HIV infection had 6% lower left ventricular ejection fraction ( P P =0.02), 29% lower peak diastolic strain rate ( P P =0.02), and higher native T1 values (969 versus 956 ms in controls; P =0.01). Pericardial effusions and myocardial fibrosis were 3 and 4× more common, respectively, in subjects with HIV infection (both P Conclusions— Treated HIV infection is associated with changes in myocardial structure and function in addition to higher rates of subclinical myocardial edema and fibrosis and frequent pericardial effusions. Chronic systemic inflammation in HIV, which involves the myocardium and pericardium, may explain the high rate of myocardial fibrosis and increased cardiac dysfunction in people living with HIV.

Background Heart failure (HF) is characterised by alterations in fatty acid and glucose metabolism. We aimed to determine if myocardial lipid is increased in HF with reduced (HFrEF) and preserved (HFpEF) ejection fraction (EF), and assess whether it is related to cardiac structure and function. Methods 25 HFrEF due to dilated cardiomyopathy (DCM), 18 HFpEF (defined by EF >50%, abnormal diastolic function, maximum oxygen consumption

Background Diabetic cardiomyopathy is a well-recognised entity, with multifactorial aetiology. We and others have previously shown impaired myocardial energetics (decreased PCr/ ATP using cardiac 31P Magnetic Resonance Spectroscopy-MRS) in patients with type II diabetes mellitus (T2DM) at rest. Furthermore, diabetic patients are known to have impaired myocardial perfusion reserve even in the absence of epicardial coronary artery disease likely due to microvascular dysfunction. However, it is unknown whether this hypoperfusion is translated to further energetic derangement at stress. Methods 27 patients (13 male, mean age 54±1.5 years; BMI 28±2.7) with T2DM and 24 healthy volunteers of similar age and BMI (13 male, mean age 51±2.6 years; BMI 26±0.84) were studied. Patients were on oral antidiabetic therapies only, with mean HBA1c 7.4±1.3% and no history of diabetic complications. Obstructive coronary artery disease (defined as> 50% lumen diameter reduction) was excluded in all patients by CT coronary angiography. Cardiac 31PMRS (3T) was performed at rest and during 8 minutes of leg exercise lying prone, with 2.5 kg weights attached to both legs. First-pass perfusion images (using a saturation recovery fast-gradient echo sequence and 0.03 mmol/kg bolus of Gadoterate meglumine (Dotarem, Guerbet LLC, France ) were also acquired at stress (3-6 minutes i.v. adenosine, 140 μg/kg/min) and rest at mid ventricular short axis. myocardial perfusion reserve index (MPRI) were measured from perfusion images. Results Left ventricular ejection fraction (LVEF) and mass index (LVMI) were similar in patients with T2DM and healthy volunteers (LVEF 70±1 vs 71±0.9%, p=0.494; LVMI 56.7 ±1.8 vs 52.6±2.4g/m 2 , p=0.168). Increases in rate pressure product with exercise (T2DM 46±36%, healthy volunteers 42±26%, P = 0.69) and adenosine stress (T2DM 40 ± 3%, healthy volunteers 39 ± 3%, P = 0.89) were similar. There was no change in PCr/ATP during exercise in healthy volunteers (rest: 2.03±0.05, exercise

OBJECTIVE Obtaining new details of radial motion of left ventricular (LV) segments using velocity-encoding cardiac MRI. METHODS Cardiac MR examinations were performed on 14 healthy volunteers aged between 19 and 26 years. Cine images for navigator-gated phase contrast velocity mapping were acquired using a black blood segmented κ-space spoiled gradient echo sequence with a temporal resolution of 13.8 ms. Peak systolic and diastolic radial velocities as well as radial velocity curves were obtained for 16 ventricular segments. RESULTS Significant differences among peak radial velocities of basal and mid-ventricular segments have been recorded. Particular patterns of segmental radial velocity curves were also noted. An additional wave of outward radial movement during the phase of rapid ventricular filling, corresponding to the expected timing of the third heart sound, appeared of particular interest. CONCLUSION The technique has allowed visualization of new details of LV radial wall motion. In particular, higher peak systolic radial velocities of anterior and inferior segments are suggestive of a relatively higher dynamics of anteroposterior vs lateral radial motion in systole. Specific patterns of radial motion of other LV segments may provide additional insights into LV mechanics. ADVANCES IN KNOWLEDGE The outward radial movement of LV segments impacted by the blood flow during rapid ventricular filling provides a potential substrate for the third heart sound. A biphasic radial expansion of the basal anteroseptal segment in early diastole is likely to be related to the simultaneous longitudinal LV displacement by the stretched great vessels following repolarization and their close apposition to this segment.

Background Cardiovascular magnetic resonance (CMR) is regarded as the gold standard for clinical assessment of the aorta, but normal dimensions are usually referenced to echocardiographic and computed tomography data and no large CMR normal reference range exists. As a result we aimed to 1) produce a normal CMR reference range of aortic diameters and 2) investigate the relationship between regional aortic size and body surface area (BSA) in a large group of healthy subjects with no vascular risk factors. Methods 447 subjects (208 male, aged 19–70 years) without identifiable cardiac risk factors (BMI range 15.7–52.6 kg/m2) underwent CMR at 1.5 T to determine aortic diameter at three levels: the ascending aorta (Ao) and proximal descending aorta (PDA) at the level of the pulmonary artery, and the abdominal aorta (DDA), at a level 12 cm distal to the PDA. In addition, 201 of these subjects had aortic root imaging, allowing for measurements at the level of the aortic valve annulus (AV), aortic sinuses and sinotubular junction (STJ). Results Normal diameters (mean ±2 SD) were; AV annulus male(♂) 24.4 ± 5.4, female (♀) 21.0 ± 3.6 mm, aortic sinus♂32.4 ± 7.7, ♀27.6 ± 5.8 mm, ST-junction ♂25.0 ± 7.4, ♀21.8 ± 5.4 mm, Ao ♂26.7 ± 7.7, ♀25.5 ± 7.4 mm, PDA ♂20.6 ± 5.6, +18.9 ± 4.0 mm, DDA ♂17.6 ± 5.1, ♀16.4 ± 4.0 mm. Aortic root and thoracic aortic diameters increased at all levels measured with BSA. No gender difference was seen in the degree of dilatation with increasing BSA (p > 0.5 for all analyses). Conclusion Across both genders, increasing body size is characterized by a modest degree of aortic dilatation, even in the absence of traditional cardiovascular risk factors.

Background— Elevated free fatty acid (FFA) levels are known to impair aortic elastic function. In obesity, FFA levels are elevated and aortic distensibility (AD) reduced in a pattern that predominantly affects the distal aorta. Despite this, the role of FFAs in obesity-related aortic stiffness remains unclear. Methods and Results— Using vascular MRI, we aimed to determine if (1) FFA level correlated with AD in obesity; and (2) whether elevating FFA acutely and subacutely in normal-weight subjects reproduced the distal pattern of AD change in obesity. To do this, regional AD was recorded in 35 normal-weight and 70 obese subjects and then correlated with FFA levels. When compared with normal weight, obesity was associated with reduced AD in a pattern predominantly affecting the distal aorta (ascending aorta by −22%, proximal descending aorta by −25%, and abdominal aorta by −35%; P r =−0.43, P Conclusions— Both intralipid infusion and a low-carbohydrate diet resulted in reduced abdominal AD (infusion −22%, diet −28%; both P

Summary Across both genders, obesity, in the absence of traditional cardiovascular risk factors, is characterized by concentric LV remodeling. Whereas males show predominantly concentric remodeling, females exhibit eccentric and concentric hypertrophy. This may explain the observed gender difference in obesity related cardiovascular mortality. Background Obesity related cardiovascular mortality, although elevated when compared to normal weight, is lower in females (♀ )t han males ( ♂ )a t every body mass index (BMI) level. Given the fact that males have less fat tissue than females at each BMI level, the reasons behind this trend are unlikely to be attributable to the effects of excess adiposity alone. As different patterns of left ventricular (LV) remodeling have been shown to have varying prognostic value, with concentric hypertrophy being more strongly predictive of cardiovascular mortality than eccentric hypertrophy, our aim was to investigate whether sex-specific differences in LV remodeling could provide an additional explanation for the observed gender difference in obesity related mortality. Methods 703 subjects (♀ n= 390, ♂ n=313) without identifiable cardiovascular risk factors, (BMI range 15.7-59.2 Kg/ M2) underwent cardiovascular magnetic resonance at 1.5 Tesla for the assessment of LV mass (g), enddiastolic volume (EDV; ml) and LV mass/volume ratio (LVM/VR).

Summary This work demonstrates that cardiac energetcics is further impaired during exercise in hypertrophic cardiomyopathy. This may be a possible reason for exercise related death in HCM. Background In hypertrophic cardiomyopathy (HCM), sarcomere mutations increase the energy cost of contraction. Impaired resting cardiac energetics as measured by phosphocreatine/adenosine triphosphate (PCr/ATP) using 31Phosphorus MR Spectroscopy(31P MRS) has been documented in animal models and patients. We hypothesize that: 1.Cardiac energetics are further impaired acutely during exercise in HCM, which does not occur in normals or athletes (physiological hypertrophy); 2. This impairment is not related to the degree of hypertrophy or late gadolinium enhancement (LGE) burden.

To determine the accuracy of visual analysis of left ventricular (LV) function in comparison with the accepted quantitative gold standard method, Cardiac Magnetic Resonance (CMR). Cine CMR imaging was performed at 1.5 T on 44 patients with a range of ejection fractions (EF, 5-80%). Clinicians (n = 18) were asked to visually assess EF after sequentially being shown cine images of a four chamber (horizontal long axis; HLA), two chamber (vertical long axis; VLA) and a short axis stack (SAS) and results were compared to a commercially available analysis package. There were strong correlations between visual and quantitative assessment. However, the EF was underestimated in all categories (by 8.4% for HLA, 8.4% for HLA + VLA and 7.9% for HLA + VLA + SAS, P all < 0.01) and particularly underestimated in mild LV impairment (17.4%, P < 0.01), less so for moderate (4.9%) and not for severe impairment (1%). Assessing more than one view of the heart improved visual assessment of LV, EF, however, clinicians underestimated EF by 8.4% on average, with particular inaccuracy in those with mild dysfunction. Given the important clinical information provided by LV assessment, quantitative analysis is recommended for accurate assessment. © 2010 Springer Science+Business Media, B.V.

Objective Using high resolution cardiovascular magnetic resonance (CMR), we aimed to detect new details of left ventricular (LV) systolic and diastolic function, to explain the twisting and longitudinal movements of the left ventricle. Methods Using CMR phase contrast velocity mapping (also called Tissue Phase Mapping) regional wall motion patterns and longitudinally and circumferentially directed movements of the left ventricle were studied using a high temporal resolution technique in healthy male subjects (n = 14, age 23 ± 3 years). Results Previously undescribed systolic and diastolic motion patterns were obtained for left ventricular segments (based on the AHA segmental) and for basal, mid and apical segments. The summation of segmental motion results in a complex pattern of ventricular twisting and longitudinal motion in the normal human heart which underlies systolic and diastolic function. As viewed from the apex, the entire LV initially rotates in a counter-clockwise direction at the beginning of ventricular systole, followed by opposing clockwise rotation of the base and counter-clockwise rotation at the apex, resulting in ventricular torsion. Simultaneously, as the entire LV moves in an apical direction during systole, the base and apex move towards each other, with little net apical displacement. The reverse of these motion patterns occur in diastole. Conclusion Left ventricular function may be a consequence of the relative orientations and moments of torque of the sub-epicardial relative to the sub-endocardial myocyte layers, with influence from tethering of the heart to adjacent structures and the directional forces associated with blood flow. Understanding the complex mechanics of the left ventricle is vital to enable these techniques to be used for the evaluation of cardiac pathology.

Methods The regional ventricular wall motion was investigated in two groups of healthy volunteers between the ages of 23 ± 3 and 66 ± 7 years old respectively, using navigator gated tissue phase mapping. The left ventricle was divided into 16 segments (six basal, six middle and four apical) and regional wall motion was studied in high temporal detail. The results were also compared with those obtained in one patient with peripheral vascular disease and in a second patient with a massive LV scar.

Purpose The purpose of this study was to obtain detailed threedimensional left ventricular (LV) wall motion in patients with ischaemic heart disease (IHD) before and after coronary artery by-pass graft (CABG) surgery, using navigator gated high temporal resolution tissue phase mapping (TPM). The technique has a higher temporal resolution compared with standard TPM analysis [1,2] and has allowed visualization of new details of LV motion.

Methods Healthy males from the University of Oxford (n = 12, age 24 ± 2) underwent twenty hours of normobaric hypoxia in purpose-built hypoxia chambers. The partial pressure of oxygen during end tidal expiration (PETO2) was kept between 50 and 60 mmHg, whilst keeping peripheral oxygen saturation (SaO2) above 80%. Cardiac function was measured using magnetic resonance imaging (MRI) and echocardiography. High-energy phosphate metabolism was measured as the ratio of phosphocreatine to ATP (PCr/ATP) by 31Phosphorus magnetic resonance spectroscopy (MRS) before and after twenty hours of hypoxia. Additionally, four subjects had blood taken for biochemical analysis every four hours.

Introduction Cardiac 31P-MRS is the only non-invasive in vivo technique for the determination of cardiac high energy phosphate metabolism. Changes in cardiac phosphocreatine to adenosine triphosphate ratios (PCr/ATP) occur in common cardiac pathologies and have diagnostic, prognostic and therapeutic utility. However, long acquisition times (20 minutes or more, depending on heart rate) required to achieve sufficient signal to noise ratios for reliable interpretation have limited the clinical utility of 31P-MRS studies in patients with severe cardiac disease.

OBJECTIVES: This study assessed 3-dimensional fusion echocardiography (3DFE), combining several real-time 3-dimensional echocardiography (RT3DE) full volumes from different transducer positions, for improvement in quality and completeness of the reconstructed image. BACKGROUND: The RT3DE technique has limited image quality and completeness of datasets even with current matrix transducers. METHODS: RT3DE datasets were acquired in 32 participants (mean age 33.7 +/- 18.8 years; 27 men, 5 women). The 3DFE technique was also performed on a cardiac phantom. The endocardial border definition of RT3DE and 3DFE segments was graded for quality: good (2), intermediate (1), poor (0), or out of sector. Short-axis and apical images were compared in RT3DE and 3DFE, yielding 2,048 segments. The images were processed to generate 3DFE and then compared with cardiac magnetic resonance. RESULTS: In the heart phantom, fused datasets showed improved contrast to noise ratio from 49.4 +/- 25.1 (single dataset) to 125.4 +/- 25.1 (6 datasets fused together). In subjects, more segments were graded as good quality with 3DFE (805 vs. 435; p < 0.0001) and fewer as intermediate (184 vs. 283; p = 0.017), poor (31 vs. 265; p < 0.0001), or out of sector (4 vs. 41; p < 0.001) compared with the single 3-dimensional dataset. End-diastolic volume (EDV) and end-systolic volume (ESV) obtained from 3-dimensional fused datasets were equivalent to those from single datasets (EDV 118.2 +/- 39 ml vs. 119.7 +/- 43 ml; p = 0.41; ESV 48.1 +/- 30 ml vs. 48.4 +/- 35 ml; p = 0.87; ejection fraction [EF] 61.0 +/- 10% vs. 61.8 +/- 10%; p = 0.44). Bland-Altman analysis showed good 95% limits of agreement for the nonfused datasets (EDV +/-46 ml; ESV +/-36 ml; EF +/-14%) and the fused datasets (EDV +/-45 ml; ESV +/-35 ml; EF +/-16%), when compared with cardiac magnetic resonance. CONCLUSIONS: Fusion of full-volume datasets resulted in an improvement in endocardial borders, image quality, and completeness of the datasets.

Background Rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) commonly involve the cardiovascular system and are associated with significant morbidity and mortality, driven by cardiovascular inflammation, microvascular and diastolic dysfunction and fibrosis. Cardiovascular magnetic resonance (CMR) can assess non-invasively cardiac function, strain, ischaemia, altered vascular function, perfusion, inflammation and fibrosis; magnetic resonance spectroscopy (MRS) provides further insights into the status of myocardial energetics and lipidosis. To date, there have been no cardiovascular MRS studies in RA and SLE patients. We hypothesised that RA and SLE would be associated with impaired myocardial energetics and lipidosis.

Results Compared to controls, patients had significantly more edema (global myocardial T2 SI ratio 1.71 ± 0.27 vs.1.56 ± 0.15), higher mean myocardial T1 (1011 ± 64 ms vs. 946 ± 23 ms) and more areas of injury measured by T2 (median 5% vs. 0%), T1 (median 32% vs. 0.7%) and LGE (median 11% vs. 0%); all p 990 ms (sensitivity 90%, specificity 91%) detected significantly larger areas of involvement than T2W and LGE imaging in patients, and additional areas of injury when T2W and LGE were negative. Using incremental thresholds, T1-mapping can display the non-ischemic patterns of injury typical of myocarditis (Figure 2).

Background Patients with diabetes mellitus (DM) of longer duration have an increased incidence of heart failure, independent of hypertension and coronary disease, as shown in large population based studies. Mechanisms of diabetic cardiomyopathy are multifactorial and not fully elucidated. Cardiovascular magnetic resonance (CMR) and magnetic resonance spectrocopy (MRS) provide a noninvasive assessment of the functional, structural and metabolic status of the heart. Here we assessed whether subclinical functional, structural and metabolic alterations can be detected using MRI in a patient cohort of early-onset, stable and uncomplicated type 2 DM. Objective The aim of this study was to assess the earliest manifestations of diabetic cardiomyopathy using multiparametric CMR and MRS in a cohort of uncomplicated type 2 DM patients with a short duration of disease. Methods

Background Hypertension (HPT) is an important risk factor for heart disease worldwide. It is already established that in hypertension there is an abnormal oxygenation response to stress (by exploiting the paramagnetic properties of deoxyhemoglobin, blood oxygen level-dependent, BOLD). Additionally, abnormal resting cardiac energetics (phosphocreatine/adenosine triphosphate, PCr/ATP, as measured by 31Phosphorus MR Spectroscopy, 31P MRS) has been reported. However, it is not known if this energetic profile worsens with the increasing energy demand of exercise, and if so, if the blunted Oxygen supply response may contribute to this. Understanding this relation can lend new insights into the pathophysiology and management of hypertensive heart disease. We hypothesized that cardiac energetic are abnormal at rest and are further impaired during acute exercise in HPT, and that this impairment is related to abnormal oxygenation during stress.

OBJECTIVE: Obtaining new details for rotational motion of left ventricular (LV) segments using velocity encoding cardiac MR and correlating the regional motion patterns to LV insertion sites. METHODS: Cardiac MR examinations were performed on 14 healthy volunteers aged between 19 and 26 years. Peak rotational velocities and circumferential velocity curves were obtained for 16 ventricular segments. RESULTS: Reduced peak clockwise velocities of anteroseptal segments (i.e. Segments 2 and 8) and peak counterclockwise velocities of inferoseptal segments (i.e. Segments 3 and 9) were the most prominent findings. The observations can be attributed to the LV insertion sites into the right ventricle, limiting the clockwise rotation of anteroseptal LV segments and the counterclockwise rotation of inferoseptal segments as viewed from the apex. Relatively lower clockwise velocities of Segment 5 and counterclockwise velocities of Segment 6 were also noted, suggesting a cardiac fixation point between these two segments, which is in close proximity to the lateral LV wall. CONCLUSION: Apart from showing different rotational patterns of LV base, mid ventricle and apex, the study showed significant differences in the rotational velocities of individual LV segments. Correlating regional wall motion with known orientation of myocardial aggregates has also provided new insights into the mechanisms of LV rotational motions during a cardiac cycle. ADVANCES IN KNOWLEDGE: LV insertion into the right ventricle limits the clockwise rotation of anteroseptal LV segments and the counterclockwise rotation of inferoseptal segments adjacent to the ventricular insertion sites. The pattern should be differentiated from wall motion abnormalities in cardiac pathology.

A 67-year-old woman initially presented with dyspnoea. Echocardiography demonstrated an inter-atrial mass. Cardiovascular magnetic resonance (CMR) showed a well-marginated mass (35 mm × 45 mm) in the inter-atrial septum (IAS) sparing the fossa ovalis, extending to the posterior right atrial wall. The mass had high signal intensity on T1-weighted images ( Panels A and B , arrows) consistent with fat, which attenuated on fat-suppression imaging ( Panels C and …

Background Although it is widely accepted that obesity is related to increased aortic size, to date, there is no large study assessing the effect of obesity, in the absence of co-morbidities, on regional aortic diameter. In addition, despite the fact that magnetic resonance imaging (MRI) is generally regarded as the gold standard technique for imaging the aorta, the vast majority of data comes from 2D echo, which has marked limitations in the setting of obesity. As a result, we aimed to use MRI to 1) establish a large

Previous studies have shown that myocardial steatosis occurs with age, diabetes, and the metabolic syndrome and that myocardial triglyceride content (MTGC) is related to concentric left ventricular hypertrophy (LVH) [(1)][1] and diastolic dysfunction [(2)][2], suggesting a direct negative effect on

Background Microvascular dysfunction in non-ischemic DCM is well established. Despite this, little is known about whether this microvascular dysfunction is severe enough to result in ischemia on a tissue level and thus contribute to the observed derangement of cardiac energetics which is also a hallmark of DCM. We hypothesized that in DCM the oxygen response of the myocardium to moderate stress is appropriate despite the presence of microvascular dysfunction.

T1 relaxation is prolonged in hypertrophic (HCM) and dilated cardiomyopathy (DCM) and reflects myocardial changes prior to presence of LGE or development of hypertrophy in HCM and wall thinning in DCM.

Background Patients with treated Human Immunodeficiency Virus-1 (HIV) infection are at increased risk of cardiovascular events. Traditionally much of this risk has been attributed to metabolic and anthropometric abnormalities associated with HIV, which are similar to the metabolic syndrome (MS), an established risk factor for cardiovascular mortality. It remains unclear whether treated HIV infection is itself associated with increased risk, via increase vascular stiffness. Methods 226 subjects (90 with HIV) were divided into 4 groups based on HIV and MS status: 1) HIV-ve/MS-ve, 2) HIV-ve/MS + ve, 3) HIV + ve/MS-ve and 4)HIV + ve/MS + ve. CMR was used to determine aortic pulse wave velocity (PWV) and regional aortic distensibility (AD). Results PWV was 11% higher and regional AD up to 14% lower in the HIV + ve/MS-ve group when compared to HIV-ve/MS-ve (p 0.99 all analyses). The HIV + ve/MS + ve group had 32% higher PWV and 30-34% lower AD than the HIV-ve/MS-ve group (all p

Background and aim Obesity confers an enormous burden of cardiovascular morbidity and mortality worldwide. Lipotoxicity has been implicated as a potential common pathway in myocyte dysfunction and ultimately apoptosis. Fat deposition in the peritoneum, the liver and around vascular structures has been linked to metabolic syndrome and subsequent cardiomyopathy. Therefore this study sought to determine the relationship between excess body fat and intracardiac lipids as assessed by 3T proton spectroscopy in women. Methods

Background In aortic stenosis (AS), there is impairment of myocardial energetics and a substrate switch with a preference to glucose metabolism and downregulation of fatty acid utilization. Whether or not this results in cardiac steatosis is unknown. We hypothesi zed that cardiac steatosis is present in severe AS and this can be assessed by 1 H magnetic resonance spectroscopy (MRS). We aimed to investigate myocardial lipid content in patients with severe AS and to examine the associations amongst steatosis, energetics and myocardial function. Methods Thirty patients with severe AS (20 symptomatic, 10 asymptomatic) and 20 normal volunteers were enrolled. Inclusion criteria were peak aortic valve gradient >50 mmHg, no other significant valvular pathology, normal left ventricular systolic function, no obstructive coronary artery disease and blood pressure

Background The accurate diagnosis of acute myocarditis on cardiovascular magnetic resonance imaging (CMR) often requires multiple modalities, including T2-weighted (T2W), early and late gadolinium imaging. Novel CMR techniques are now available, including bright-blood T2W-CMR, and T1-mapping which is also sensitive to changes in free water content. We hypothesized that these emerging methods can serve as new diagnostic criteria for myocarditis.

Objective To determine the effects of short term exercise training on cardiac metabolism and function, during rest and exercise, in patients with dilated cardiomyopathy (DCM). Background Exercise training may play a beneficial role in patients with DCM, however the effects on cardiac function at rest and during exercise have not been defined. Methods Patients with DCM (n = 15, age 58 ± 2 years), stable on medical therapy, were studied before and after 8 weeks of training for 20 minutes, 5 times per week on a home exercise bike. Cardiac volumes and function were measured using MR at 3T during rest and leg exercise. High energy phosphate metabolism was measured as the ratio of phosphocreatine to ATP (PCr/ATP) by 31 Phosphorus magnetic resonance spectroscopy (MRS) at 3T. Quality of life scores were calculated using the Minnesota Heart Failure Questionnaire and 6 minute walk tests were used to determine exercise capacity. All assessments were repeated after the 8 week training period. Results At baseline assessment, the average left ventricular ejection fraction (LVEF) was 38 ± 3%, which did not increase with leg exercise. After the 8 weeks of home exercise there was a 6% improvement in resting LVEF to 44 ± 3% (Figure, p