Femtosecond Laser-Excitation-Driven High Frequency Standing Spin Waves in Nanoscale Dielectric Thin Films of Iron Garnets.

We demonstrate that femtosecond laser pulses allow triggering high-frequency standing spin-wave modes in nanoscale thin films of a bismuth-substituted yttrium iron garnet. By varying the strength of the external magnetic field, we prove that two distinct branches of the dispersion relation are excited for all the modes. This is reflected in particular at a very weak magnetic field (∼33 mT) by a spin dynamics with a frequency up to 15 GHz, which is 15 times higher than the one associated with the ferromagnetic resonance mode. We argue that this phenomenon is triggered by ultrafast changes of the magnetic anisotropy via laser excitation of incoherent and coherent phonons. These findings open exciting prospects for ultrafast photo magnonics.

Extended heart failure clinic follow-up in low-risk patients: a randomized clinical trial (NorthStar).

BACKGROUND: Outpatient follow-up in specialized heart failure clinics (HFCs) is recommended by current guidelines and implemented in most European countries, but the optimal duration of HFC programmes has not been established. Nor is it known whether all or only high-risk patients, e.g. identified by NT-proBNP, might benefit from an extended HFC follow-up. METHODS AND RESULTS: In a multi-centre setting, we randomly assigned 921 clinically stable systolic heart failure (HF) outpatients on optimal medical therapy to undergo either an extended follow-up in the HFC (n = 461) or referral back to their general practitioner (GP) (n = 460). The primary composite endpoint was death or a cardiovascular admission. Secondary endpoints included mortality, an HF admission, quality of life, number of days admitted, and number of admissions. The median age of the patients was 69 years; 23% were females; the median left ventricular ejection fraction was 0.30; and the median NT-proBNP was 801 pg/mL; 89% were in NYHA class I-II. The median follow-up was 2.5 years. Time-to-event did not differ between groups (HFC vs. GP) (HR: 1.17, 95% CI: 0.95-1.45, P = 0.149). The two groups did not differ with respect to any of the secondary endpoints at the follow-up (P> 0.05 for all). In high-risk patients identified by NT-proBNP ≥1000 pg/mL, no benefit from HFC follow-up was found (P = 0.721). CONCLUSION: Irrespective of the level of NT-proBNP stable HF patients on optimal medical therapy do not benefit from long-term follow-up in a specialized HFC in a publicly funded universal access healthcare system. Heart failure patients on optimal medical therapy with mild or moderate symptoms are safely managed by their personal GP. TRIAL REGISTRATION: www.Centerwatch.com: 173491 (NorthStar).

Design and methodology of the NorthStar Study: NT-proBNP stratified follow-up in outpatient heart failure clinics -- a randomized Danish multicenter study.

BACKGROUND: Randomized clinical trials have shown that newly discharged and symptomatic patients with chronic heart failure (CHF) benefit from follow-up in a specialized heart failure clinic (HFC). Clinical stable and educated patients are usually discharged from the HFC when on optimal therapy. It is unknown if risk stratification using natriuretic peptides could identify patients who would benefit from longer-term follow-up. Furthermore, data on the use of natriuretic peptides for monitoring of stable patients with CHF are sparse. AIMS: The aims of this study are to test the hypothesis that clinical stable, educated, and medical optimized patients with CHF with N-terminal pro-brain natriuretic peptide (NT-proBNP) levels > or = 1,000 pg/mL benefit from long-term follow-up in an HFC and to assess the efficacy of NT-proBNP monitoring. METHODS: A total of 1,250 clinically stable, medically optimized, and educated patients with CHF will be enrolled from 18 HFCs in Denmark. The patients will be randomized to treatment in general practice, to a standard follow-up program in the HFC, or to NT-proBNP monitoring in the HFC. The patients will be followed for 30 months (median). RESULTS: Data will be collected from 2006 to 2009. At present (March 2008), 720 patients are randomized. Results expect to be presented in the second half of 2010. CONCLUSIONS: This article outlines the design of the NorthStar study. If our hypotheses are confirmed, the results will help cardiologists and nurses in HFCs to identify patients who may benefit from long-term follow-up. Our results may also indicate whether patients with CHF will benefit from adding serial NT-proBNP measurements to usual clinical monitoring.

Spectrally resolved optical probing of laser induced magnetization dynamics in bismuth iron garnet.

The spectrally resolved magnetization dynamics in bismuth iron garnet shows a fluence dependent light induced modification of the magneto-optical Faraday spectrum. It is demonstrated that the relative contributions from the tetrahedral and octahedral iron sites to the Faraday spectrum change due to the impact of the pump pulse. This change explains the observed deviation from a linear dependence of the amplitude of the oscillations on the fluence, as expected for the inverse Faraday effect.

Cross-talk between the heart and adipose tissue in cachectic heart failure patients with respect to alterations in body composition: a prospective study.

OBJECTIVES: Cardiac cachexia (CC) is associated with changes in body composition. Lipolysis and increased energy expenditure caused by A- and B natriuretic peptides (NPs) have been suggested to play a role in CC. We tested the hypothesis that neurohormones and adipokines are associated with body composition in CC and that a progressive loss of fat free mass (FFM) and fat mass (FM) takes place. METHODS: Body composition with regard to FFM, FM, and body fat distribution was assessed by dual energy X-ray absorptiometry (DXA) in 19 non-diabetic patients with chronic heart failure (CHF) and CC and 38 controls (non-cachectic CHF and individuals with prior myocardial infarction-both n = 19) who were followed for 12 months. Biomarkers of neurohormonal stimulation, inflammation, and endothelial dysfunction were measured. RESULTS: N-terminal proBNP (NT-proBNP), midregional proANP (MR-proANP), and total adiponectin were elevated in CHF (p<0.001) and correlated inversely to BMI and FM. An inverse correlation was observed between pro-adrenomedullin (MR-proADM) and FFM. During follow up body weight was unaltered in all groups even though FM increased by 1.35 kg (p<0.05) and FFM decreased by 0.5 kg (p<0.05) in CC patients. The latter correlated inversely to baseline NT-proBNP, MR-proANP, and MR-proADM (p<0.05). No correlation to changes in FM was found. CONCLUSIONS: FM was associated with plasma NPs and total adiponectin at baseline; whereas changes in FM and FFM did not correlate to changes in NPs or adiponectin during follow up. Prospectively, FFM decreased but FM increased, despite stable body weight in CC.

Prevalence of cachexia in chronic heart failure and characteristics of body composition and metabolic status.

The prevalence of cardiac cachexia has previously been estimated to 8-42 %. However, novel treatment strategies for chronic heart failure (CHF) have improved and decreased morbidity and mortality. Therefore, we aimed to reassess the prevalence of cachexia in an outpatient CHF clinic and to characterize a CHF population with and without cachexia with respect to body composition and related biomarkers. From 2008 to 2011, we screened 238 optimally treated, non-diabetic CHF patients for cardiac cachexia, defined as unintentional non-oedematous weight loss of >5 % over ≥6 months. CHF patients (LVEF <45 %) with cachexia (n = 19) and without (n = 19) were compared to controls with prior myocardial infarction and left ventricular ejection fraction (LVEF) >45 % (n = 19). The groups were matched for age, sex, and kidney function. Body composition was assessed by dual energy X-ray absorptiometry. The prevalence of cachexia was 10.5 %. Abdominal fat ± SD (%) was reduced in cachectic CHF: 27.4 ± 10.0 versus 37.5 ± 10.6 % (CHF, no cachexia) and 40.6 ± 8.0 % (controls), (P < 0.001). NT-proBNP levels were inversely correlated to abdominal fat in a multivariate linear regression analysis adjusted for known predictors of NT-proBNP (LVEF and NYHA); (ß = -0.28; P = 0.018). Myostatin levels were reduced in cachectic CHF compared to controls (P = 0.013). The prevalence of cachexia in stable CHF, treated according to recent guidelines, is lower than previously anticipated. Body alterations in cachexia consist mainly of reduced abdominal fat mass, and its inverse correlation to NT-proBNP suggests involvement of abdominal lipolysis. Our data do not support a role of circulating myostatin as a biomarker for muscle wasting.