PURPOSE:Left atrial (LA) dimensions have been identified as anatomical predictors for atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI). The value of LA function compared to pure LA anatomical risk prediction for AF recurrence after PVI is not well investigated. Cardiovascular magnetic resonance (CMR) is able to simultaneously assess LA anatomical, tissue and functional markers within one examination. The hypothesis of this explorative study was that CMR-derived LA strain has incremental value for the prediction of AF recurrence after PVI.METHOD:Fifty-two patients with paroxysmal or persistent AF were retrospectively enrolled for CMR (1.5T) prior to PVI. Strain-analysis was derived from standard cine images in 4-, 3- and 2-chamber view. LA function was divided into LA reservoir strain and strain rate (εs and SRs), LA conduit (εe and SRe) and LA booster pump function (εa and SRa). The primary endpoint was recurrence of AF within one year after PVI.RESULTS:Twelve patients (23 %) presented with AF recurrence. There was no difference in age, LA size as well as LA sphericity index between the groups. Patients with AF recurrence (68.3 ± 5.5 years, 66 % male) showed significantly reduced LA booster pump function compared to the patients without AF recurrence (66.3 ± 10.5 years, 50 % male) (εa: p = 0.015; SRa: p = 0.036). In binomial logistic regression analyses, the only predictor for AF recurrence after PVI was εa (p = 0.033).CONCLUSIONS:In this descriptive study, impaired LA booster pump function predicted AF recurrence one year after PVI. Compared to further LA strain and anatomical parameters, LA booster pump might serve as additional predictor of AF recurrence.

Abstract Background To identify and stratify coronary artery disease (CAD) non-invasively, cardiovascular magnetic resonance (CMR) derived perfusion imaging holds a class Ia recommendation. As Gold standard, hyperemia is induced by an intravenous application of adenosine in a body weight adapted dosage over a constant time. However, adenosin has two disadvantages: 1.) efficacy of adenosine to induce maximal hyperemia via peripheral line is imperfect and 2.) additional adenosine specific effects exclude patients having comorbidities (e.g. AV-blocks and obstructive lung disease). Fortunately, regadenoson as aselective A2A-receptor agonist has the main advantages of being easier to handle (bolus application) and to be not restricted to patients without specific comorbidities. However, there is a lack of comprehensive data on the prognostic value of regadenoson perfusion CMR to predict clinical endpoints. To assess the predictive value of regadenoson perfusion CMR, our hypothesis was, that a “negative” ischemia test result by regadenoson-CMR predicted freedom from MACE at 12 month. Methods 676 patients, with known or suspected CAD with intermediate risk were retrospectively analyzed from May 2015 till December 2016. Cardiovascular risk factors (CVRF) like age, sex, arterial hypertension, dis-/hyperlipidemia, cigarette smoking status and diabetes were documented. All included patients received perfusion CMR (Philips 1.5 Tesla) with regadenoson (0.4 mg) and a positive ischemia test was defined as perfusion defects in ≥1,5 cardiac segments (using the 17-segment model). Major cardiovascular events (MACE) were defined as cardiovascular death, rehospitalisation due to myocardial infarction and rehospitalisation due to revascularization. The follow-up time was 12 month. Results 80,3% (n=543) of all analyzed patients showed negative ischemia testing in CMR and were thus followed up for 12 month. From these patients, 284 (52,3%) had a pre-existing coronary artery disease. The mean age regarding only the patients with negative ischemia was 66 years (65% male and 35% female) with 1,35±1,03 CVRF. The primary endpoint (MACE) occurred in 6 patients (1,1%): 3 (0,6%) died due to cardiovascular events, 1 (0,2%) suffered from a myocardial infarction and 2 (0,4%) received coronary revascularization. Consequently, an event-free survival was correctly predicted in 98,9% of all patients. No undesirable adverse reactions have appeared. Conclusion Regadenoson-CMR predicts a very low MACE-rate and an event-free survival in 98,9% in over 500 patients. In our study, Regadenoson was well tolerated and no side effects were reported.

Interventional cardiovascular magnetic resonance (iCMR) might evolve as a technique to improve procedural success rates in cardiovascular interventions by combining intraprocedural guidance and simultaneous lesion imaging. The objective of the present study was to prove feasibility and estimate safety of renal sympathetic denervation guided by real-time iCMR using active tracking. Six pigs were examined in a 1.5 T MRI-System (Achieva, Philips Healthcare, Best, Netherlands) equipped with non-invasive hemodynamic control and in-room monitors displaying an interventional software platform [Interventional MRI Suite (iSuite), Philips Research, Hamburg, Germany]. MR-guided renal denervation was performed using a MR conditional non-irrigated ablation catheter with active tracking (Imricor, Burnsville, MN, USA). Real-time imaging for device guidance was performed with a TFE sequence, vessel patency was assessed with a 3D non-contrast angiography and velocity encoded imaging. Oedema of the renal artery was visualized by a high-resolution T2 SPIR sequence. Renal sympathetic denervation was feasible in all cases with survival of all animals. Non-contrast angiography displayed renal artery patency accompanied by equal flow conditions before and after the ablation in all cases as measured by velocity encoded imaging. Oedema imaging displayed a significant increase in relative signal intensity at renal artery ablations sites pre and post intervention (p < 0.05). The histologic examination revealed no signs of perforation or bleeding, while sufficient ablation lesions could be depicted. MR-guided renal sympathetic denervation using active tracking is feasible and the initial data suggest safety of this procedure. MR-guided renal sympathetic denervation offers the inherent strength of high soft tissue contrast thereby providing target information without the use of iodinated contrast agents or radiation.

Background To investigate the value of cardiovascular magnetic resonance (CMR) and T2-mapping in patients with systemic lupus erythematosus (SLE) and persistent dyspnoea without sings for pulmonary involvement (conventional X-rays and pulmonary function testing) as a possible sign for myocardial involvement. Methods 11 women fulfilling the ACR criteria for SLE (mean age 37±14.81 years, mean disease duration 13.75±8.47 years, mean SLEDAI 6.82±3) with persistent dyspnoea (at least NYHA II) but absence of pathological findings in electrocardiogram (ECG), echocardiography and lung function were investigated by CMR. CMR was conducted with a 1.5 Tesla MRI-System (Achieva, Philips, Best, Netherlands) using a 32-channel coil. T2 mapping was done using a respiration navigator gated Gradient and Spin-Echo sequence (GRASE, 15 T2 echoes separated by 10 ms, res: 1 × 1 × 10 mm², 3 short axis slices). Images were post-processed using software based on the LabView environment for local T2 value generation (T2 mapping). Strain analysis was conducted entering cine-images into myocardial feature tracking (FTI) analysis software (TomTec Imaging Systems, Unterschleisheim, Germany). A cohort eleven of age and gender matched healthy controls (HC) served as controls. Results All SLE patients showed significantly extended T2 times as a sign of local inflammation compared with age matched healthy controls (p Conclusions SLE patients with persistent dyspnoea in absence of pathological findings in ECG and echocardiography showed significantly extended T2-times in MRI as a sign of local fluid content as a part of myocardial inflammation, reduced GLS and diastolic dysfunction, which would be missed by using conventional technics. CMR and T2-mapping is a possible tool for the investigation of a cardiac involvement in SLE patients and should be investigated in clinical studies.

Endomyocardial biopsy (EMB) is considered to be the diagnostic gold-standard in detection of myocardial-inflammation. EMB is usually conducted under fluoroscopy without any specific target information. Specific target-information provided by cardiovascular magnetic resonance (CMR) may improve specificity of EMB. The aim was to investigate feasibility and safety of CMR-guided and targeted EMB in a preclinical-model using passively-tracked devices. Procedures were performed on a MRI-System equipped with an Interventional Software-Platform for real-time imaging. Ex vivo experiments were conducted to optimize visibility of the guide-sheath. In vivo experiments were conducted in 2 pigs for technical feasibility assessment and in 4 pigs after acute myocardial infarction to test feasibility of guided and lesion targeted EMB. For anatomical real-time imaging a single-shot-balanced-SSFP-sequence was applied. Myocardial targets were identified under real-time imaging (single-shot-T2 (sshT2) and single-shot Late-Gadolinium-Enhancement (sshLGE) sequences). Ex vivo experiments demonstrated best visibility of continuously labelled guide-sheath. CMR-guided EMB was feasible in all cases without major complications. Likewise, lesion-targeting endomyocardial biopsy was feasible in two cases. Biopsies exhibited appropriate sizes and qualities. Real-time lesion sequences revealed comparable CNR values to clinical-protocols. Real-time imaging of lesions showed following signal- and contrast-to-noise ratios (SNR/CNR): SNR of sshT2- and sshLGE was 124 ± 35 and 67 ± 51 respectively, whereas CNR was 81 ± 30 and 57 ± 44. This study demonstrates feasibility and safety of CMR-guided and basically targeted EMB with passively-tracked devices. Signal-to-noise ratios of real-time sequences is non-inferior to standard sequences for lesion detection. CMR-guidance may improve diagnostic accuracy of EMB since CMR can detect myocardial-targets under real-time-imaging.

Background To investigate the value of cardiovascular magnetic resonance (CMR) and T2-mapping in patients with systemic lupus erythematosus (SLE) and persistent dyspnoea without sings for pulmonary involvement (conventional X-rays and pulmonary function testing) as a possible sign for myocardial involvement. Methods 11 women fulfilling the ACR criteria for SLE (mean age 37±14.81 years, mean disease duration 13.75±8.47 years, mean SLEDAI 6.82±3) with persistent dyspnoea (at least NYHA II) but absence of pathological findings in electrocardiogram (ECG), echocardiography and lung function were investigated by CMR. CMR was conducted with a 1.5 Tesla MRI-System (Achieva, Philips, Best, Netherlands) using a 32-channel coil. T2 mapping was done using a respiration navigator gated Gradient and Spin-Echo sequence (GRASE, 15 T2 echoes separated by 10 ms, res: 1 × 1 × 10 mm², 3 short axis slices). Images were post-processed using software based on the LabView environment for local T2 value generation (T2 mapping). Strain analysis was conducted entering cine-images into myocardial feature tracking (FTI) analysis software (TomTec Imaging Systems, Unterschleißheim, Germany). A cohort eleven of age and gender matched healthy controls (HC) served as controls. Results All SLE patients showed significantly extended T2 times as a sign of local inflammation compared with age matched healthy controls (p<0.05). Moreover, the global systolic longitudinal strain (GLS) as means by systolic function was significantly decreased. In addition, global early diastolic strain rate displayed diastolic dysfunction in comparison to controls. Conclusions SLE patients with persistent dyspnoea in absence of pathological findings in ECG and echocardiography showed significantly extended T2-times in MRI as a sign of local fluid content as a part of myocardial inflammation, reduced GLS and diastolic dysfunction, which would be missed by using conventional technics. CMR and T2-mapping is a possible tool for the investigation of a cardiac involvement in SLE patients and should be investigated in clinical studies.

BACKGROUND:Patients with severe aortic stenosis (AS) are subjected to left ventricular hypertrophy (LVH) with increasing morbidity and mortality. Transcatheter aortic valve replacement (TAVR) induces reverse left ventricular remodeling which can be monitored by cardiovascular magnetic resonance (CMR). CMR is able to analyze myocardial tissue properties by magnetic relaxation times (parametric CMR). The objective of this study was to study myocardial T2 relaxation in reverse ventricular remodeling after TAVR.METHODS:Forty-three patients with severe AS (19 males, 81.9 ± 4.9 years) underwent CMR with T2 mapping before and 6 months after TAVR. A cohort of age- and gender-matched volunteers served as controls. Analyzed parameters included left ventricular ejection fraction (LV-EF), mass indexed to body surface area (LVMi), interventricular septum thickness (IVS), end-diastolic volume (LVEDV), global longitudinal strain (GLS), peak diastolic strain rate (SRe) and myocardial T2 values.RESULTS:CMR characteristics for patients with AS displayed LVH concomitant to elevated myocardial T2 values, reduced GLS and SRe. Patients with T2 values above 70.2 ms at baseline were characterized by eccentric hypertrophy with reduced LV-EF. T2 values decreased after TAVR (67.4 ± 3.4 to 63.3 ± 4.2 ms, p < 0.01) during left ventricular remodeling. Patients with T2 values above 70.2 ms at baseline exhibited pronounced reverse remodeling which proved to be a significant predictor of LV-EF improvement and LVEDV reduction in uni- and multivariate analyses.CONCLUSIONS:Multiparametric CMR can be used to characterize myocardial hypertrophy due to severe AS and to monitor myocardial adaptations after TAVR. It may provide additional information in the prediction of left ventricular remodeling after TAVR.

Aims The aim of this study was to determine the value of T2 mapping for the non-invasive assessment of myocardial inflammation in different stages of systolic left ventricular dysfunction in dilated cardiomyopathy (DCM) in comparison with endomyocardial biopsy (EMB). Methods and results A total of 132 subjects were enrolled between 2013 and 2016 (62 controls and 70 patients with DCM). All patients underwent CMR at 1.5 T and received coronary angiogram and EMB. CMR applied standard protocols including T2 mapping with Gradient And SpinEcho sequence (GRASE). Global T2 relaxation time was significantly increased in patients with DCM compared to the healthy controls (T2 time DCM vs. controls: 65.9 ± 6.2 vs. 60.0 ± 4.2 ms; P < 0.001). Of note, patients with the presence of inflammatory cells in EMB exhibited further elevation of T2 values (T2 time in patients with the presence of inflammatory cells vs. T2 time in patients without: 68.8 ± 5.8 vs. 64.7 ± 5.9 ms; P = 0.02). Receiver operating characteristic analysis of our data deciphered a global myocardial T2 time >65.3 ms as the best cut-off for distinction between the healthy controls and patients with myocardial inflammation [sensitivity 93%, specificity 90%, P < 0.01, area under the curve (AUC) 0.95]. In patients with DCM, this threshold identified patients with biopsy-proven inflammation with a sensitivity of 79% and specificity 58% (AUC 0.72). Conclusion In patients with DCM and presence of inflammatory cells in the myocardium, myocardial T2 relaxation times may help to non-invasively detect myocardial inflammation. Although there is an overlap of T2 values between patients and healthy controls, T2 mapping may facilitate the identification of patients who may benefit from EMB for therapeutic decision-making.

Urea cycle defects belong to the most common metabolic disorders with a cumulative incidence of 1:8000. A common trait of urea cycle defects is a disturbed detoxification of ammonia leading to hyperammonemia in the event of a high nitrogen load. Most patients develop symptoms in the neonatal period or in infancy, e.g. vomiting, seizures and disturbed consciousness. Depending on the affected enzyme and its residual activity, patients differ in the age at first presentation, the character and severity of symptoms and in the susceptibility to metabolic derangement. The presence of hyperammonemia and an altered plasma amino acid profile give the essential diagnostic clues. Since modern therapeutic measures have prolonged the life expectancy of these patients and provided the possibility of a first presentation in adulthood, patients with urea cycle defects have become an increasing challenge in internal medicine. The reported case series illustrates the heterogeneous clinical course of these disorders from childhood to adulthood.

Urea cycle defects belong to the most common metabolic disorders with a cumulative incidence of 1:8000. A common trait of urea cycle defects is a disturbed detoxification of ammonia leading to hyperammonemia in the event of a high nitrogen load. Most patients develop symptoms in the neonatal period or in infancy, e. g. vomiting, seizures and disturbed consciousness. Depending on the affected enzyme and its residual activity, patients differ in the age at first presentation, the character and severity of symptoms and in the susceptibility to metabolic derangement. The presence of hyperammonemia and an altered plasma amino acid profile give the essential diagnostic clues. Since modern therapeutic measures have prolonged the life expectancy of these patients and provided the possibility of a first presentation in adulthood, patients with urea cycle defects have become an increasing challenge in internal medicine. The reported case series illustrates the heterogeneous clinical course of these disorders from childhood to adulthood.

We study quantum (Shubnikov-de Haas and de Haas-van Alphen) oscillations and angular oscillations of the reluctance in the organic quasi-two-dimensional metal (BO)2Clx(H2O)y. We show that the Fermi surface in this compound consists of a slightly corrugated cylinder with its axis perpendicular to the conducting plane. The cross section of the cylinder in this plane is a perfect circle of radius kF≃3×107 cm−1. The effective carrier mass associated with this cylinder is m*=(1.65–2.0) m0 in the conducting plane, while the Dingle temperature is TD=3–4 K.

C. Graeni1, C. Eichhorn1, L. Biere1, V. Agarwal1, K. Kaneko1, V.L. Murthy2, M. Steigner3, R. Blankstein3, M. Jerosch-Herold1, R.Y. Kwong1. 1Brigham and Women’s Hospital, Non-invasive Cardiovascular Imaging, Cardiovascular Division, Boston, United States of America; 2University of Michigan, Cardiovascular Imaging, Department of Radiology, Frankel Cardiovascular Center, Ann Arbor, United States of America; 3Brigham and Women’s Hospital, Non-invasive Cardiovascular Imaging, Department of Radiology, Boston, United States of America