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This study explored whether cardiac magnetic resonance (CMR) could help select patients who could benefit from revascularization by identifying inducible myocardial ischemia and viability in the perfusion territory of the artery with chronic total occlusion (CTO).The benefit of revascularization using percutaneous coronary intervention (PCI) in CTO is controversial. CMR offers incomparable left ventricular (LV) systolic function assessment in addition to potent ischemic burden quantification and reliable myocardial viability analysis. Whether CMR guided CTO revascularization would be helpful to such patients has not yet been explored fully.A prospective study of 50 consecutive CTO patients was conducted. Of 50 patients undergoing baseline stress CMR, 32 (64%) were selected for recanalization based on the presence of significant inducible perfusion deficit and myocardial viability within the CTO arterial territory. Patients were rescanned 3 months after successful CTO recanalization.At baseline, myocardial perfusion reserve (MPR) in the CTO territory was significantly reduced compared with the remote region (1.8 ± 0.72 vs. 2.2 ± 0.7; p = 0.01). MPR in the CTO region improved significantly after PCI (to 2.3 ± 0.9; p = 0.02 vs. baseline) with complete or near-complete resolution of CTO related perfusion defect in 90% of patients. Remote territory MPR was unchanged after PCI (2.5 ± 1.2; p = NS vs. baseline). The LV ejection fraction increased from 63 ± 13% to 67 ± 12% (p 0.0001) and end-systolic volume decreased from 65 ± 38 to 56 ± 38 ml (p 0.001) 3 months after CTO PCI. Importantly, despite minimal post-procedural infarction due to distal embolization and side branch occlusion in 8 of 32 patients (25%), the total Seattle Angina Questionnaire score improved from a median of 54 (range 45 to 74) at baseline to 89 (range 77 to 98) after CTO recanalization (p 0.0001).In this small group of patients showing CMR evidence of significant myocardial inducible perfusion defect and viability, CTO recanalization reduces ischemic burden, favors reverse remodeling, and ameliorates quality of life.

BACKGROUND: There is a need for improved worldwide access to tissue iron quantification using T2* cardiovascular magnetic resonance (CMR). One route to facilitate this would be simple in-line T2* analysis widely available on MR scanners. We therefore compared our clinically validated and established T2* method at Royal Brompton Hospital (RBH T2*) against a novel work-in-progress (WIP) sequence with in-line T2* measurement from Siemens (WIP T2*). METHODS: Healthy volunteers (n = 22) and patients with iron overload (n = 78) were recruited (53 males, median age 34 years). A 1.5 T study (Magnetom Avanto, Siemens) was performed on all subjects. The same mid-ventricular short axis cardiac slice and transaxial slice through the liver were used to acquire both RBH T2* images and WIP T2* maps for each participant. Cardiac white blood (WB) and black blood (BB) sequences were acquired. Intraobserver, interobserver and interstudy reproducibility were measured on the same data from a subset of 20 participants. RESULTS: Liver T2* values ranged from 0.8 to 35.7 ms (median 5.1 ms) and cardiac T2* values from 6.0 to 52.3 ms (median 31 ms). The coefficient of variance (CoV) values for direct comparison of T2* values by RBH and WIP were 6.1-7.8 % across techniques. Accurate delineation of the septum was difficult on some WIP T2* maps due to artefacts. The inability to manually correct for noise by truncation of erroneous later echo times led to some overestimation of T2* using WIP T2* compared with the RBH T2*. Reproducibility CoV results for RBH T2* ranged from 1.5 to 5.7 % which were better than the reproducibility of WIP T2* values of 4.1-16.6 %. CONCLUSIONS: Iron estimation using the T2* CMR sequence in combination with Siemens' in-line data processing is generally satisfactory and may help facilitate global access to tissue iron assessment. The current automated T2* map technique is less good for tissue iron assessment with noisy data at low T2* values.

Background— The role of mitral valve repair (MVR) during coronary artery bypass grafting (CABG) in patients with moderate ischemic mitral regurgitation (MR) is uncertain. We conducted a randomized, controlled trial to determine whether repairing the mitral valve during CABG may improve functional capacity and left ventricular reverse remodeling compared with CABG alone. Methods and Results— Seventy-three patients referred for CABG with moderate ischemic MR and an ejection fraction >30% were randomized to receive CABG plus MVR (34 patients) or CABG only (39 patients). The study was stopped early after review of interim data. At 1 year, there was a greater improvement in the primary end point of peak oxygen consumption in the CABG plus MVR group compared with the CABG group (3.3 mL/kg/min versus 0.8 mL/kg/min; P 2 , 28.2 mL/beat, and 557.4 pg/mL, respectively versus 4.4 mL/m 2 ( P =0.002), 9.2 mL/beat ( P =0.001), and 394.7 pg/mL ( P =0.003), respectively. Operation duration, blood transfusion, intubation duration, and hospital stay duration were greater in the CABG plus MVR group. Deaths at 30 days and 1 year were similar in both groups: 3% and 9%, respectively in the CABG plus MVR group, versus 3% ( P =1.00) and 5% ( P =0.66), respectively in the CABG group. Conclusions— Adding mitral annuloplasty to CABG in patients with moderate ischemic MR may improve functional capacity, left ventricular reverse remodeling, MR severity, and B-type natriuretic peptide levels, compared with CABG alone. The impact of these benefits on longer term clinical outcomes remains to be defined. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00413998.

Purpose To improve 3D volume-selective turbo spin echo (TSE) carotid artery wall imaging by incorporating navigators to reduce artifacts caused by swallowing. Materials and Methods Images were acquired on a Siemens Magnetom Sonata 1.5T scanner. 3D volume-selective TSE scans of the carotid arteries were acquired in six healthy volunteers. A cross-pair navigator placed on the back of the tongue was used to detect swallowing and movement. Two swallowing patterns were tested: 1) a single swallow approximately halfway through the scan time, at the center of kz, and 2) repeated swallowing as often as possible throughout the scan period. Images were acquired with and without navigators for comparison. Signal intensity in the lumen was quantified for the quality of blood suppression, and the clarity of the vessel wall in the common carotid was ranked by four independent blinded observers. Results In general, lower signal intensity was recorded in the lumen, and decreased blurring and ghosting were observed on scans with navigator control. This reduction in lumen signal intensity signifies an improvement in the black-blood imaging technique. The differences likely reflect the improved double inversion/blood suppression efficiency due to cycles being rejected when the heart rate changed at the point of swallowing, or decreased motional blurring/ghosting of tissue when the navigator is used, or a combination of these two effects. A statistical analysis of image quality showed a significant difference between navigated and non-navigated scans as scored by four independent, blinded observers. For both swallowing patterns, the mean score for the navigator images was on average 0.6 greater than that of non-navigator images (on a scoring scale of 0–5, where 0 = no vessel visible, and 5 = good delineation and blood suppression) and P-values for all observers were less than 0.01. Overall, the central swallow scans were scored higher than the repeated swallow scans. One reason for this may be the fact that the heart rate increased on swallowing, and this often lasted for one or two cardiac cycles after the navigator returned to the normal acceptance position. The effect of the increased heart rate after swallowing is likely to have an effect on double inversion blood suppression efficiency. Therefore, the increased amount of heart rate changes with repeated swallowing may have a greater adverse effect, even if the navigator rejects data views during the swallowing motion. Conclusion The clarity of vessel wall delineation and the apparent efficiency of blood suppression are reduced by swallowing during acquisition. Both motion blurring and quality of blood suppression are factors that can be improved with the use of a navigator accept/reject method. J. Magn. Reson. Imaging 2005. © 2005 Wiley-Liss, Inc.

A 60-year-old man with known atrial fibrillation (AF) was referred for routine cardiovascular magnetic resonance imaging (CMR) prior to AF ablation. He was normotensive and had no other previous medical conditions. A transthoracic echocardiogram had shown good systolic function with moderate left ventricular hypertrophy and mildly dilated atria (Fig. 1). Figure 1: Four-chamber transthoracic echocardiography demonstrating moderate myocardial hypertrophy and mildly dilated atria. Initial CMR imaging for anatomy and function demonstrated normal ventricular size and mildly impaired systolic function (ejection fraction = 50%, normal >55%) with no significant valvular pathology. There was asymmetrical septal hypertrophy measuring 16 mm (normal

ss Open Acce Oral presentation Recanalization of coronary chronic total occlusion guided by cardiovascular magnetic resonance imaging and its relation with health outcome measures Chiara Bucciarelli-Ducci*1, Didier Locca1, Rory O'Hanlon1, Joanna Petryka1, Agata Grasso1, Wright Christine2, Ricardo Wage1, Karen Symmonds1, Eleni Asimacopoulos1, Peter Gatehouse1, Sanjay Prasad1, Carlo Di Mario2 and Dudley Pennell1

Introduction CMR assessment of the mitral valve provides unique insights into its normal annular and leaflet motion. Although various other modalities have investigated mitral annular and leaflet motion in isolation, CMR imaging allows assessment of both the temporal and spatial relationship of mitral annular and leaflet motion throughout the cardiac cycle. Such insights provided by CMR may be important in understanding various disease processes affecting the mitral valve and the impact of these on normal mitral valve function, and in developing techniques for the surgical repair of diseased mitral valves.

Methods 15 healthy volunteers (31±5 years, 8 males) with no known medical conditions, on no medication, underwent CMR scans (Avanto, Siemens, 1.5T) on two separate attendances with an 11 heart beat MOLLI 5(3)3. Following frequency adjustment, native T1 maps were obtained twice on a basal and a mid-ventricular slice respectively. 15 mins following GBCA administration (0.1 mmol/kg, Gadobutrol, Bayer, Germany) both image planes were acquired again twice. Pixel-wise T1 maps were analyzed offline by 2 independent blinded operators. A Region Of Interest was manually drawn in the septum for myocardium and blood in native and post gad images as shown in fig 1.

Background Chronic iron overload is prevalent and prognosis relates to the severity of cardiac siderosis. The black blood (BB) T2* technique is validated, with calibration against myocardial tissue iron at 1.5T. There are potential advantages of 3T over 1.5T in assessing T2*, but preliminary studies at 3T used white blood imaging, had small patient numbers, methodological differences, and poor signal-noise ratio in severe iron overload precluding assessment across a wide dynamic range. A novel noise correction (NC) algorithm is superior to other techniques in severe iron loading. We assessed BB T2* iron measurement at 3T against the 1.5T gold standard and incorporated the NC algorithm. Methods

Background T2* relaxometry offers a non-invasive method to accurately quantify myocardial iron levels, thus aiding the diagnosis and assessment of prognosis of patients. Two T2* sequences are used clinically: the single breathhold multi-echo gradient echo white blood (WB) and black blood (BB) techniques. At 1.5T, BB T2* has superior reproducibility and fewer artefacts than WB T2*. We compared BB and WB T2* iron measurement at 3T and compared results with corresponding 1.5T measurements.

ss Open Acce Poster presentation Diagnostic performance of perfusion cardiovascular magnetic resonance compared with gated myocardial perfusion spect in patients with known or suspected coronary artery disease Jonathan Lyne*1, Chiara Bucciarelli-Ducci1, Eliana Reyes2, Ravi Assomull1, Joanna Petryka1, Stuart Watkins1, Peter Gatehouse1, Micheal Roughton1, Karen Symmonds1, Sanjay Prasad1, Richard Underwood3 and Dudley Pennell1

Background T1 mapping in end diastole requires correct identification of the diastolic pause, and an appropriate input of the trigger delay time (TD) into acquisition parameters to ensure parametric mapping during the true diastolic pause for minimal motion-related blurring of myocardium. This diascan can be derived for individual patients from either the 4 chamber or the short axis stack. However, this additional step adds complexity and time to the scan and potentially introduces error. We investigated whether the TD could be estimated from the heart rate (HR) to simplify MOLLI acquisitions.