Dabrafenib, alone or in combination with trametinib, in BRAF V600-mutated pediatric Langerhans cell histiocytosis.

Langerhans cell histiocytosis (LCH) is a rare, heterogenous, neoplastic disorder primarily affecting children. BRAF mutations have been reported in >50% of patients with LCH. The selective BRAF inhibitor, dabrafenib, in combination with the MEK1/2 inhibitor, trametinib, has been approved in select BRAF V600-mutant solid tumors. Two open-label phase 1/2 studies were conducted in pediatric patients with BRAF V600-mutant, recurrent/refractory malignancies treated with dabrafenib monotherapy (CDRB436A2102; NCT01677741) or dabrafenib plus trametinib (CTMT212X2101; NCT02124772). The primary objectives of both studies were to determine safe and tolerable doses that achieve similar exposure to the approved doses for adults. Secondary objectives included safety, tolerability, and preliminary antitumor activity. Thirteen and 12 patients with BRAF V600-mutant LCH received dabrafenib monotherapy and in combination with trametinib, respectively. Investigator-assessed objective response rates per Histiocyte Society criteria were 76.9% (95% confidence interval [CI], 46.2-95.0) and 58.3% (95% CI, 27.7-84.8) in the monotherapy and combination studies, respectively. More than 90% of responses were ongoing at study completion. The most common treatment-related adverse events (AEs) were vomiting and increased blood creatinine with monotherapy and pyrexia, diarrhea, dry skin, decreased neutrophil count, and vomiting with combination therapy. Two patients each discontinued treatment with monotherapy and combination therapy because of AEs. Overall, dabrafenib monotherapy or in combination with trametinib demonstrated clinical efficacy and manageable toxicity in relapsed/refractory BRAF V600-mutant pediatric LCH, with most responses ongoing. Safety was consistent with that reported in other pediatric and adult conditions treated with dabrafenib plus trametinib.

Long-term outcomes of osilodrostat in Cushing's disease: LINC 3 study extension.

Objective: To investigate the long-term efficacy and tolerability of osilodrostat, a potent oral 11ß-hydroxylase inhibitor, for treating Cushing's disease (CD). Design/methods: A total of 137 adults with CD and mean 24-h urinary free cortisol (mUFC) > 1.5 × upper limit of normal (ULN) received osilodrostat (starting dose 2 mg bid; maximum 30 mg bid) during the prospective, Phase III, 48-week LINC 3 (NCT02180217) core study. Patients benefiting from osilodrostat at week 48 could enter the optional extension (ending when all patients had received ≥ 72 weeks of treatment or discontinued). Efficacy and safety were assessed for all enrolled patients from the core study baseline. Results: Median osilodrostat exposure from the core study baseline to study end was 130 weeks (range 1-245) and median average dose was 7.4 mg/day (range 0.8-46.6). The reduction in mean mUFC achieved during the core was maintained during the extension and remained ≤ ULN. Of 106 patients, 86 (81%) patients who entered the extension had mUFC ≤ ULN at week 72. Improvements in cardiovascular/metabolic-related parameters, physical manifestations of hypercortisolism (fat pads, central obesity, rubor, striae, and hirsutism in females), and quality of life in the core study were also maintained or improved further during the extension. No new safety signals were reported; 15/137 (10.9%) and 12/106 (11.3%) patients discontinued for adverse events during the core and extension, respectively. Mean testosterone in females decreased towards baseline levels during the extension. Conclusions: Data from this large, multicentre trial show that long-term treatment with osilodrostat sustains cortisol normalisation alongside clinical benefits in most patients with CD and is well tolerated.

Randomized Trial of Osilodrostat for the Treatment of Cushing Disease.

CONTEXT: Cushing disease, a chronic hypercortisolism disorder, is associated with considerable morbidity and mortality. Normalizing cortisol production is the primary treatment goal. OBJECTIVE: We aimed to evaluate the safety and efficacy of osilodrostat, a potent, orally available 11ßhydroxylase inhibitor, compared with placebo in patients with Cushing disease. METHODS: LINC 4 was a phase III, multicenter trial comprising an initial 12-week, randomized, double-blind, placebo-controlled (osilodrostat:placebo, 2:1) period followed by a 36-week, open-label treatment period (NCT02697734). Adult patients (aged 18-75 years) with confirmed Cushing disease and mean urinary free cortisol (mUFC) excretion ≥ 1.3 times the upper limit of normal (ULN) were eligible. The primary endpoint was the proportion of randomized patients with mUFC ≤ ULN at week 12. The key secondary endpoint was the proportion achieving mUFC ≤ ULN at week 36 (after 24 weeks' open-label osilodrostat). RESULTS: Seventy-three patients (median age, 39 years [range, 19-67]; mean/median mUFC, 3.1 × ULN/2.5 × ULN) received randomized treatment with osilodrostat (n = 48) or placebo (n = 25). At week 12, significantly more osilodrostat (77%) than placebo (8%) patients achieved mUFC ≤ ULN (odds ratio 43.4; 95% CI 7.1, 343.2; P < 0.0001). Response was maintained at week 36, when 81% (95% CI 69.9, 89.1) of all patients achieved mUFC ≤ ULN. The most common adverse events during the placebo-controlled period (osilodrostat vs placebo) were decreased appetite (37.5% vs 16.0%), arthralgia (35.4% vs 8.0%), and nausea (31.3% vs 12.0%). CONCLUSION: Osilodrostat rapidly normalized mUFC excretion in most patients with Cushing disease and maintained this effect throughout the study. The safety profile was favorable.

Is Cardiomegaly an Indication of "Heart-Sparing Effect" in Small Fetuses?

INTRODUCTION: This study aimed to test the hypothesis that cardiac size is maintained in small fetuses presenting with cardiomegaly. MATERIALS AND METHODS: We identified singleton fetuses with estimated fetal weight <10th centile and with cardiomegaly without another more likely cardiac or extra-cardiac cause. We used Z-scores for cardiac and thoracic circumferences normalized for gestational age (GA), biparietal diameter (BPD), head circumference (HC), and femur length (FL), obtained from 188 normally grown fetuses. RESULTS: When comparing chest size, small fetuses had significantly lower thoracic circumferences median Z-scores (IQR) for GA = -4.82 (-6.15 to -3.51), BPD = -2.42 (-4.04 to -1.48), HC = -2.72 (-4.53 to -1.90), and FL = -1.60 (-2.87 to -0.71); p < 0.001 for all. When comparing heart size, small fetuses showed lower cardiac circumferences median Z-scores (IQR) for GA = -1.59 (-2.79 to -0.16); p < 0.001, similar cardiac circumferences Z-scores for BPD = 0.29 (-0.65 to 1.28); p = 0.284 and HC = 0.11 (-1.13 to 0.96); p = 0.953, and higher cardiac circumferences Z-scores for FL = 0.94 (-0.05 to 2.13); p < 0.001. CONCLUSIONS: Our results show that in small fetuses with cardiomegaly, the heart maintains normal dimensions when normalized to cranial diameters and higher dimensions when normalized to long bones. This provides insight into cardiac adaptation to adverse intrauterine environment.

Six-minute walk test: prognostic value and effects of nebivolol versus placebo in elderly patients with heart failure from the SENIORS trial.

BACKGROUND: There is limited information about the 6-min walk test (6MWT) in elderly patients with heart failure. We evaluated 6MWT and the effect of nebivolol on 6MWT from the SENIORS trial. METHODS AND RESULTS: The SENIORS trial evaluated nebivolol versus placebo on death and hospitalisation in patients aged ≥ 70 years with heart failure. A total of 1982 patients undertook a 6MWT at baseline and 1716 patients at 6 months. Patients were divided into tertiles (≤ 200 m, 201 to ≤ 300 m and > 300 m) and to change in distance walked between baseline and 6 months (< 0 m, 0 to < 30 m and ≥ 30 m). The primary outcome was all-cause mortality and cardiovascular hospital admission. Secondary endpoint was all-cause mortality. Baseline walk distance of ≤ 200 m incurred a greater risk of the primary and secondary outcomes (HR 1.41, CI 95% 1.17-1.69, p < 0.001) and (HR 1.37, CI 95% 1.05-1.78, p = 0.019). A decline in walk distance over 6 months was associated with increased risk of clinical events. Nebivolol had no influence on change in walk distance over 6 months. CONCLUSIONS: The 6MWT has prognostic utility in elderly patients. Those who walked less than 200 m were at highest risk. Nebivolol had no effect on 6MWT.

Long-term safety and efficacy of subcutaneous pasireotide in patients with Cushing's disease: interim results from a long-term real-world evidence study.

PURPOSE: Clinical trials have demonstrated the favorable efficacy/safety profile of pasireotide in patients with Cushing's disease (CD). We report interim long-term results of an ongoing real-world evidence study of subcutaneous pasireotide in patients with CD. METHODS: Adults with CD receiving pasireotide, initiated before (prior-use) or at study entry (new-use), were monitored for ≤ 3 years during a multicenter observational study ( http://clinicaltrials.gov identifier NCT02310269). Primary objective was to assess long-term safety of pasireotide alone or with other CD therapies. RESULTS: At the time of this interim analysis, 127 patients had received pasireotide (new-use, n = 31; prior-use, n = 96). Eight patients had completed the 3-year observation period, 53 were ongoing, and 66 had discontinued. Among 31 new-use and 92 prior-use patients with ≥ 1 safety assessment, respectively: 24 (77%) and 37 (40%) had drug-related adverse events (AEs); 7 (23%) and 10 (11%) had serious drug-related AEs. Most common drug-related AEs were nausea (14%), hyperglycemia (11%) and diarrhea (11%); these were more frequently reported in new users and mostly of mild-to-moderate severity. 14 (45%) new-use and 15 (16%) prior-use patients experienced hyperglycemia-related AEs. Mean urinary free cortisol (mUFC) was within normal range at baseline and months 1, 12 and 24, respectively, in: 1/16 (6%), 9/18 (50%), 1/3 (33%) and 0/0 new users; 28/43 (65%), 15/27 (56%), 27/33 (82%) and 12/19 (63%) prior users. CONCLUSIONS: Pasireotide is well tolerated and provides sustained reductions in mUFC during real-world treatment of CD. The lower rate of hyperglycemia-related AEs in prior users suggests that hyperglycemia tends not to deteriorate if effectively managed soon after onset. CLINICAL TRIAL REGISTRATION NUMBER: NCT02310269.

Long-term efficacy and safety of once-monthly pasireotide in Cushing's disease: A Phase III extension study.

OBJECTIVES: Many patients with Cushing's disease (CD) require chronic pharmacotherapy to control their hypercortisolism. We evaluated the efficacy and safety of long-acting pasireotide during a long-term extension study in patients with CD. DESIGN: Open-label extension to a 12-month Phase III study of long-acting pasireotide in CD (N = 150; NCT01374906). PATIENTS: Patients with mean urinary free cortisol (mUFC) ≤ upper limit of normal (ULN) or receiving clinical benefit at core study end could continue long-acting pasireotide during the extension. RESULTS: Eighty-one of 150 (54.0%) enrolled patients entered the extension. Median overall exposure to pasireotide at study end was 23.9 months; 39/81 (48.1%) patients completed the extension (received ≥ 12 months' treatment during the extension and could transit to a separate pasireotide safety study). mUFC was ≤ULN in 42/81 (51.9%), 13/81 (16.0%) and 43/81 (53.1%) patients at extension baseline, month (M) 36 and last assessment. Median mUFC remained within normal limits. Median late-night salivary cortisol was 2.6 × ULN at core baseline and 1.3 × ULN at M36. Clinical improvements were sustained over time. Forty-two (51.9%) patients discontinued during the extension: 25 (30.9%) before M24 and 17 (21.0%) after M24. Hyperglycaemia-related AEs occurred in 39.5% of patients. Mean fasting glucose (FPG) and glycated haemoglobin (HbA1c ) were stable during the extension, with antidiabetic medication initiated/escalated in some patients. Sixty-six (81.5%) and 71 (88.9%) patients were classified as having diabetes (HbA1c  ≥ 6.5%, FPG ≥ 7.0 mmol/L, antidiabetic medication use, or history of diabetes) at extension baseline and last assessment. CONCLUSIONS: Long-acting pasireotide provided sustained biochemical and clinical improvements, with no new safety signals emerging, supporting its use as an effective long-term therapy for CD.

Efficacy and safety of once-monthly pasireotide in Cushing's disease: a 12 month clinical trial.

BACKGROUND: Cushing's disease is a rare debilitating endocrine disorder for which few prospective interventional studies have been done. We report results of the first phase 3 trial assessing long-acting intramuscular pasireotide in patients with Cushing's disease. METHODS: In this phase 3 clinical trial we recruited patients aged 18 years or older with persistent, recurrent, or de-novo (non-surgical candidates) Cushing's disease who had a mean urinary free cortisol (mUFC) concentration (from three 24 h samples) of 1·5-5·0 times the upper limit of normal (ULN), a normal or greater than normal morning plasma adrenocorticotropic hormone concentration, and a pituitary source of Cushing's syndrome, from 57 sites across 19 countries. Exclusion criteria included previous pasireotide treatment, mitotane therapy within 6 months, and pituitary irradiation within 10 years. We randomly allocated patients 1:1 (block size of four) using an interactive-response-technology system to intramuscular pasireotide 10 mg or 30 mg every 4 weeks for 12 months (in the core phase). We stratified randomisation by screening mUFC concentration (1·5 to <2·0 × ULN and 2·0-5·0 × ULN). The dose could be uptitrated (from 10 mg to 30 mg or from 30 mg to 40 mg) at month 4 if the mUFC concentration was greater than 1·5 × ULN, and at month 7, month 9, or month 12 if the mUFC concentration was greater than 1·0 × ULN. Investigators, patients, site personnel, and those assessing outcomes were masked to dose group allocation. The primary endpoint was the proportion of patients in each group with an mUFC concentration of less than or equal to the ULN at month 7. Efficacy analyses were based on intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01374906. FINDINGS: Between Dec 28, 2011, and Dec 9, 2014, we randomly allocated 150 patients to receive pasireotide 10 mg (74 [49%] patients) or 30 mg (76 [51%] patients). The primary efficacy endpoint was met by 31 (41·9% [95% CI 30·5-53·9]) of 74 patients in the 10 mg group and 31 (40·8% [29·7-52·7]) of 76 in the 30 mg group. The most common adverse events were hyperglycaemia (36 [49%] in the 10 mg group and 36 [47%] in the 30 mg group), diarrhoea (26 [35%] and 33 [43%]), cholelithiasis (15 [20%] and 34 [45%]), diabetes mellitus (14 [19%] and 18 [24%]), and nausea (15 [20%] and 16 [21%]). Serious adverse events suspected to be study drug related were reported in eight (11%) patients in the 10 mg group and four (5%) in the 30 mg group. Two (3%) patients in the 30 mg group died during the study (pulmonary artery thrombosis and cardiorespiratory failure); neither death was judged to be related to the study drug. INTERPRETATION: Long-acting pasireotide normalised mUFC concentration in about 40% of patients with Cushing's disease at month 7 and had a similar safety profile to that of twice-daily subcutaneous pasireotide. Long-acting pasireotide is an efficacious treatment option for some patients with Cushing's disease who have persistent or recurrent disease after initial surgery or are not surgical candidates, and provides a convenient monthly administration schedule. FUNDING: Novartis Pharma AG.

Prevalence and Prognostic Significance of Right Ventricular Systolic Dysfunction in Patients Undergoing Transcatheter Aortic Valve Implantation.

BACKGROUND: Cardiovascular magnetic resonance (CMR) can provide important structural information in patients undergoing transcatheter aortic valve implantation. Although CMR is considered the standard of reference for measuring ventricular volumes and mass, the relationship between CMR findings of right ventricular (RV) function and outcomes after transcatheter aortic valve implantation has not previously been reported. METHODS AND RESULTS: A total of 190 patients underwent 1.5 Tesla CMR before transcatheter aortic valve implantation. Steady-state free precession sequences were used for aortic valve planimetry and to assess ventricular volumes and mass. Semiautomated image analysis was performed by 2 specialist reviewers blinded to patient treatment. Patient follow-up was obtained from the Office of National Statistics mortality database. The median age was 81.0 (interquartile range, 74.9-85.5) years; 50.0% were women. Impaired RV function (RV ejection fraction ≤50%) was present in 45 (23.7%) patients. Patients with RV dysfunction had poorer left ventricular ejection fractions (42% versus 69%), higher indexed left ventricular end-systolic volumes (96 versus 40 mL), and greater indexed left ventricular mass (101 versus 85 g/m(2); P<0.01 for all) than those with normal RV function. Median follow-up was 850 days; 21 of 45 (46.7%) patients with RV dysfunction died, compared with 43 of 145 (29.7%) patients with normal RV function (P=0.035). After adjustment for significant baseline variables, both RV ejection fraction ≤50% (hazard ratio, 2.12; P=0.017) and indexed aortic valve area (hazard ratio, 4.16; P=0.025) were independently associated with survival. CONCLUSIONS: RV function, measured on preprocedural CMR, is an independent predictor of mortality after transcatheter aortic valve implantation. CMR assessment of RV function may be important in the risk stratification of patients undergoing transcatheter aortic valve implantation.

Clinical and economic consequences of non-cardiac incidental findings detected on cardiovascular computed tomography performed prior to transcatheter aortic valve implantation (TAVI).

Transcatheter aortic valve implantation (TAVI) is an effective treatment option for patients with severe degenerative aortic valve stenosis who are high risk for conventional surgery. Computed tomography (CT) performed prior to TAVI can detect pathologies that could influence outcomes following the procedure, however the incidence, cost, and clinical impact of incidental findings has not previously been investigated. 279 patients underwent CT; 188 subsequently had TAVI and 91 were declined. Incidental findings were classified as clinically significant (requiring treatment), indeterminate (requiring further assessment), or clinically insignificant. The primary outcome measure was all-cause mortality up to 3 years. Costs incurred by additional investigations resultant to incidental findings were estimated using the UK Department of Health Payment Tariff. Incidental findings were common in both the TAVI and medical therapy cohorts (54.8 vs. 70.3%; P = 0.014). Subsequently, 45 extra investigations were recommended for the TAVI cohort, at an overall average cost of £32.69 per TAVI patient. In a univariate model, survival was significantly associated with the presence of a clinically significant or indeterminate finding (HR 1.61; P = 0.021). However, on multivariate analysis outcomes after TAVI were not influenced by any category of incidental finding. Incidental findings are common on CT scans performed prior to TAVI. However, the total cost involved in investigating these findings is low, and incidental findings do not independently identify patients with poorer outcomes after TAVI. The discovery of an incidental finding on CT should not necessarily influence or delay the decision to perform TAVI.

Systemic right ventricular fibrosis detected by cardiovascular magnetic resonance is associated with clinical outcome, mainly new-onset atrial arrhythmia, in patients after atrial redirection surgery for transposition of the great arteries.

BACKGROUND: We hypothesized that fibrosis detected by late gadolinium enhancement (LGE) cardiovascular magnetic resonance predicts outcomes in patients with transposition of the great arteries post atrial redirection surgery. These patients have a systemic right ventricle (RV) and are at risk of arrhythmia, premature RV failure, and sudden death. METHODS AND RESULTS: Fifty-five patients (aged 27±7 years) underwent LGE cardiovascular magnetic resonance and were followed for a median 7.8 (interquartile range, 3.8-9.6) years in a prospective single-center cohort study. RV LGE was present in 31 (56%) patients. The prespecified composite clinical end point comprised new-onset sustained tachyarrhythmia (atrial/ventricular) or decompensated heart failure admission/transplantation/death. Univariate predictors of the composite end point (n=22 patients; 19 atrial/2 ventricular tachyarrhythmia, 1 death) included RV LGE presence and extent, RV volumes/mass/ejection fraction, right atrial area, peak Vo(2), and age at repair. In bivariate analysis, RV LGE presence was independently associated with the composite end point (hazard ratio, 4.95 [95% confidence interval, 1.60-15.28]; P=0.005), and only percent predicted peak Vo(2) remained significantly associated with cardiac events after controlling for RV LGE (hazard ratio, 0.80 [95% confidence interval, 0.68-0.95]; P=0.009/5%). In 8 of 9 patients with >1 event, atrial tachyarrhythmia, itself a known risk factor for mortality, occurred first. There was agreement between location and extent of RV LGE at in vivo cardiovascular magnetic resonance and histologically documented focal RV fibrosis in an explanted heart. There was RV LGE progression in a different case restudied for clinical indications. CONCLUSIONS: Systemic RV LGE is strongly associated with adverse clinical outcome especially arrhythmia in transposition of the great arteries, thus LGE cardiovascular magnetic resonance should be incorporated in risk stratification of these patients.

Utility of the SENIORS elderly heart failure risk model applied to the RICA registry of acute heart failure.

BACKGROUND: Heart failure (HF) is predominantly a disease of the elderly. Reliable risk stratification would help in the management of this population, but no model has been well evaluated in elderly HF patients in both acute and chronic settings and not being restricted by ejection fraction. To evaluate the utility of the SENIORS risk model, developed from a clinical trial of elderly patients with chronic HF, in an independent cohort (National Spanish Registry: RICA) of elderly acute HF patients. METHODS: We applied the SENIORS risk model to 926 patients in RICA to estimate risk at one year of a) composite outcome of all-cause mortality or cardiovascular hospital admission and b) all-cause mortality. RESULTS: In the RICA registry mean age was 78years, mean ejection fraction 51% and 87% were in NYHA II and III. At one year death/CV hospitalization occurred in 31.9% and all-cause mortality in 19.5%. The risk model provided good separation of Kaplan Meier curves stratified by tertile for death/CV hospitalization and all-cause mortality. The observed versus expected rates of death/CV hospitalization in the lowest, middle and highest risk tertiles were (%) 34/24, 45/41 and 57/67, and for death 13/16, 32/38 and 44/70 respectively. C-statistic for all-cause mortality or CV hospitalization was 0.60 and for all-cause mortality 0.66. CONCLUSION: The SENIORS risk model was a reliable tool for relative risk stratification among acute heart failure patients in a "real world" registry, but predicted versus observed risk showed some variability. The model provides a useful basis for clinical risk prediction.

Does manual therapy provide additional benefit to breathing retraining in the management of dysfunctional breathing? A randomised controlled trial.

PURPOSE: Dysfunctional breathing (DB) is associated with an abnormal breathing pattern, unexplained breathlessness and significant patient morbidity. Treatment involves breathing retraining through respiratory physiotherapy. Recently, manual therapy (MT) has also been used, but no evidence exists to validate its use. This study sought to investigate whether MT produces additional benefit when compared with breathing retraining alone in patients with DB. METHODS: Sixty subjects with primary DB were randomised into either breathing retraining (standard treatment; n = 30) or breathing retraining plus MT (intervention; n = 30) group. Both the groups received standardised respiratory physiotherapy, which included: DB education, breathing retraining, home regimen, and audio disc. Intervention group subjects additionally received MT following further assessment. Data from 57 subjects were analysed. RESULTS: At baseline, standard treatment group subjects were statistically younger (41.7 + 13.5 versus 50.8 + 13.0 years; p = 0.001) with higher Nijmegen scores (38.6 + 9.5 versus 31.5 + 6.9; p = 0.001). However, no significant difference was found between the groups for primary outcome Nijmegen score (95% CI (-1.1, 6.6) p = 0.162), or any secondary outcomes (Hospital Anxiety & Depression Score, spirometry or exercise tolerance). CONCLUSION: Breathing retraining is currently the mainstay of treatment for patients with DB. The results of this study suggest MT provides no additional benefit in this patient group. IMPLICATIONS FOR REHABILITATION: Dysfunctional breathing (DB) is associated with significant patient morbidity but often goes unrecognised, leading to prolonged investigation and significant use of health care resources. Breathing retraining remains the primary management of this condition. However, physiotherapists are also using manual therapy (MT) as an adjunctive treatment for patients with DB. However, the results of this study suggest that MT provides no further benefit and cannot be recommended in the clinical management of this condition.

Calibration of myocardial T2 and T1 against iron concentration.

BACKGROUND: The assessment of myocardial iron using T2* cardiovascular magnetic resonance (CMR) has been validated and calibrated, and is in clinical use. However, there is very limited data assessing the relaxation parameters T1 and T2 for measurement of human myocardial iron. METHODS: Twelve hearts were examined from transfusion-dependent patients: 11 with end-stage heart failure, either following death (n=7) or cardiac transplantation (n=4), and 1 heart from a patient who died from a stroke with no cardiac iron loading. Ex-vivo R1 and R2 measurements (R1=1/T1 and R2=1/T2) at 1.5 Tesla were compared with myocardial iron concentration measured using inductively coupled plasma atomic emission spectroscopy. RESULTS: From a single myocardial slice in formalin which was repeatedly examined, a modest decrease in T2 was observed with time, from mean (± SD) 23.7 ± 0.93 ms at baseline (13 days after death and formalin fixation) to 18.5 ± 1.41 ms at day 566 (p<0.001). Raw T2 values were therefore adjusted to correct for this fall over time. Myocardial R2 was correlated with iron concentration [Fe] (R2 0.566, p<0.001), but the correlation was stronger between LnR2 and Ln[Fe] (R2 0.790, p<0.001). The relation was [Fe] = 5081•(T2)-2.22 between T2 (ms) and myocardial iron (mg/g dry weight). Analysis of T1 proved challenging with a dichotomous distribution of T1, with very short T1 (mean 72.3 ± 25.8 ms) that was independent of iron concentration in all hearts stored in formalin for greater than 12 months. In the remaining hearts stored for <10 weeks prior to scanning, LnR1 and iron concentration were correlated but with marked scatter (R2 0.517, p<0.001). A linear relationship was present between T1 and T2 in the hearts stored for a short period (R2 0.657, p<0.001). CONCLUSION: Myocardial T2 correlates well with myocardial iron concentration, which raises the possibility that T2 may provide additive information to T2* for patients with myocardial siderosis. However, ex-vivo T1 measurements are less reliable due to the severe chemical effects of formalin on T1 shortening, and therefore T1 calibration may only be practical from in-vivo human studies.

Coronary microvascular ischemia in hypertrophic cardiomyopathy - a pixel-wise quantitative cardiovascular magnetic resonance perfusion study.

BACKGROUND: Microvascular dysfunction in HCM has been associated with adverse clinical outcomes. Advances in quantitative cardiovascular magnetic resonance (CMR) perfusion imaging now allow myocardial blood flow to be quantified at the pixel level. We applied these techniques to investigate the spectrum of microvascular dysfunction in hypertrophic cardiomyopathy (HCM) and to explore its relationship with fibrosis and wall thickness. METHODS: CMR perfusion imaging was undertaken during adenosine-induced hyperemia and again at rest in 35 patients together with late gadolinium enhancement (LGE) imaging. Myocardial blood flow (MBF) was quantified on a pixel-by-pixel basis from CMR perfusion images using a Fermi-constrained deconvolution algorithm. Regions-of-interest (ROI) in hypoperfused and hyperemic myocardium were identified from the MBF pixel maps. The myocardium was also divided into 16 AHA segments. RESULTS: Resting MBF was significantly higher in the endocardium than in the epicardium (mean ± SD: 1.25 ± 0.35 ml/g/min versus 1.20 ± 0.35 ml/g/min, P<0.001), a pattern that reversed with stress (2.00 ± 0.76 ml/g/min versus 2.36 ± 0.83 ml/g/min, P<0.001). ROI analysis revealed 11 (31%) patients with stress MBF lower than resting values (1.05 ± 0.39 ml/g/min versus 1.22 ± 0.36 ml/g/min, P=0.021). There was a significant negative association between hyperemic MBF and wall thickness (ß=-0.047 ml/g/min per mm, 95% CI: -0.057 to -0.038, P<0.001) and a significantly lower probability of fibrosis in a segment with increasing hyperemic MBF (odds ratio per ml/g/min: 0.086, 95% CI: 0.078 to 0.095, P=0.003). CONCLUSIONS: Pixel-wise quantitative CMR perfusion imaging identifies a subgroup of patients with HCM that have localised severe microvascular dysfunction which may give rise to myocardial ischemia.

Influence of systolic blood pressure on clinical outcomes in elderly heart failure patients treated with nebivolol: data from the SENIORS trial.

AIMS: There is limited information about the effects of beta-blockers in heart failure (HF) stratified by blood pressure, especially in the elderly and those with preserved EF. We evaluate the effects of nebivolol on outcomes in elderly patients with HF stratified by baseline systolic blood pressure (SBP) and EF. METHODS AND RESULTS: The SENIORS trial evaluated the effects of nebivolol and enrolled 2128 patients ≥ 70 years of age with HF. Patients were divided into three baseline pre-treatment SBP categories (<110, 110-130, and >130 mmHg). In addition, we evaluated the influence of SBP (≤ 130 and > 130 mmHg) on patients with LVEF <40% vs. ≥ 40%. Low baseline SBP was associated with worse clinical outcomes irrespective of treatment group, both in patients with reduced EF and in those with preserved EF. Nebivolol had similar benefits irrespective of baseline SBP: the hazard ratio (HR) for primary outcome of all-cause mortality or cardiovascular hospitalization in the three SBP categories for nebivolol vs. placebo was 0.85 [95% confidence interval (CI) 0.50-1.45], 0.79 (95% CI 0.61-1.01), and 0.88 (95% CI 0.72-1.07), respectively (P for interaction = 0.61). Similar results were obtained for the secondary endpoint of all-cause mortality. There was no significant interaction for the effects of nebivolol by baseline SBP stratified by LVEF. CONCLUSIONS: Elderly HF patients with lower SBP have a worse outcome than those with higher SBP, but nebivolol appears to be safe and well tolerated, with similar benefits on the composite outcome of death or cardiovascular hospital admission irrespective of baseline SBP and LVEF.

Effects of nebivolol on biomarkers in elderly patients with heart failure.

BACKGROUND: Heart failure activates neurohormones, and elevated levels of brain natriuretic peptide (BNP) are associated with adverse outcomes. The SENIORS trial showed that nebivolol, a highly selective beta-1 antagonist with vasodilating properties, reduced the composite outcome of all cause mortality or cardiovascular hospital admissions in older patients with heart failure. We explored the effects of nebivolol on a range of neurohormones, cytokines and markers of nitric oxide activity in heart failure. METHODS: In a subset of patients in SENIORS we measured N-terminal pro-brain natriuretic peptide (NT-BNP), pro atrial natriuretic peptide (Pro-ANP), endothelin-1 (ET-1), peripheral norepinephrine (PNE), soluble Fas (sFas), soluble Fas-ligand (sFas-L), tumour necrosis factor-alpha (TNF-α), serum uric acid (SUA), symmetrical dimethyl arginine (SDMA), arginine, citrulline and asymmetrical dimethyl arginine (ADMA) at baseline (before study drug), at 6 months and 12 months in a prespecified substudy. RESULTS: One hundred and six patients were enrolled and 75 had a baseline and at least one follow-up sample. There were no significant differences in neurohormone cytokines or nitric oxide markers measured between the two groups at six or twelve months. NT-ProBNP showed a numerical increase in the nebivolol group compared to placebo (P=0.08) and sFas showed a numerical increase in patients on placebo (P=0.08). Mean baseline LVEF was 35% in both groups and at 12 months was 43% on nebivolol group and 34% on placebo group (P=0.01). CONCLUSION: There were trends but no clear changes associated with nebivolol in neurohormones, cytokines or markers of nitric oxide activity in this study of elderly patients with heart failure. Further studies are needed to understand the mechanistic effects of beta blockers on biomarkers in heart failure.

Biopsy-based calibration of T2* magnetic resonance for estimation of liver iron concentration and comparison with R2 Ferriscan.

BACKGROUND: There is a need to standardise non-invasive measurements of liver iron concentrations (LIC) so clear inferences can be drawn about body iron levels that are associated with hepatic and extra-hepatic complications of iron overload. Since the first demonstration of an inverse relationship between biopsy LIC and liver magnetic resonance (MR) using a proof-of-concept T2* sequence, MR technology has advanced dramatically with a shorter minimum echo-time, closer inter-echo spacing and constant repetition time. These important advances allow more accurate calculation of liver T2* especially in patients with high LIC. METHODS: Here, we used an optimised liver T2* sequence calibrated against 50 liver biopsy samples on 25 patients with transfusional haemosiderosis using ordinary least squares linear regression, and assessed the method reproducibility in 96 scans over an LIC range up to 42 mg/g dry weight (dw) using Bland-Altman plots. Using mixed model linear regression we compared the new T2*-LIC with R2-LIC (Ferriscan) on 92 scans in 54 patients with transfusional haemosiderosis and examined method agreement using Bland-Altman approach. RESULTS: Strong linear correlation between ln(T2*) and ln(LIC) led to the calibration equation LIC = 31.94(T2*)-1.014. This yielded LIC values approximately 2.2 times higher than the proof-of-concept T2* method. Comparing this new T2*-LIC with the R2-LIC (Ferriscan) technique in 92 scans, we observed a close relationship between the two methods for values up to 10 mg/g dw, however the method agreement was poor. CONCLUSIONS: New calibration of T2* against liver biopsy estimates LIC in a reproducible way, correcting the proof-of-concept calibration by 2.2 times. Due to poor agreement, both methods should be used separately to diagnose or rule out liver iron overload in patients with increased ferritin.

Role of late gadolinium enhancement cardiovascular magnetic resonance in the risk stratification of hypertrophic cardiomyopathy.

OBJECTIVE: Myocardial fibrosis identified by late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) in patients with hypertrophic cardiomyopathy (HCM) is associated with adverse cardiovascular events, but its value as an independent risk factor for sudden cardiac death (SCD) is unknown. We investigated the role of LGE-CMR in the risk stratification of HCM. METHODS: We conducted a prospective cohort study in a tertiary referral centre. Consecutive patients with HCM (n=711, median age 56.3 years, IQR 46.7-66.6; 70.0% male) underwent LGE-CMR and were followed for a median 3.5 years. The primary end point was SCD or aborted SCD. RESULTS: Overall, 471 patients (66.2%) had myocardial fibrosis (median 5.9% of left ventricular mass, IQR: 2.2-13.3). Twenty-two (3.1%) reached the primary end point. The extent but not the presence of fibrosis was a significant univariable predictor of the primary end point (HR per 5% LGE: 1.24, 95% CI 1.06 to 1.45; p=0.007 and HR for LGE: 2.69, 95% CI 0.91 to 7.97; p=0.073, respectively). However, on multivariable analysis, only LV-EF remained statistically significant (HR: 0.92, 95% CI 0.89 to 0.95; p<0.001). For the secondary outcome of cardiovascular mortality/aborted SCD, the presence and the amount of fibrosis were significant predictors on univariable but not multivariable analysis after adjusting for LV-EF and non-sustained ventricular tachycardia. CONCLUSIONS: The amount of myocardial fibrosis was a strong univariable predictor of SCD risk. However, this effect was not maintained after adjusting for LV-EF. Further work is required to elucidate the interrelationship between fibrosis and traditional predictors of outcome in HCM.

Organizational index mapping to identify focal sources during persistent atrial fibrillation.

INTRODUCTION: Localized rotors have been implicated in the mechanism of persistent atrial fibrillation (AF). Although regions of highest dominant frequency (DF) on spectral analysis of the left atrium (LA) have been said to identify rotors, other mechanisms such as wavefront collisions will sporadically also generate an inconsistent distribution of high DF. We hypothesized that if drivers of AF were present, their distinctive spectral characteristics would result more from their temporal stability than their high frequency. METHODS AND RESULTS: Ten patients with persistent AF underwent LA noncontact mapping. Following subtraction of far-field ventricular components, noncontact electrograms at 256 sites underwent fast Fourier transform. Mean absolute difference in DF between 5 sequential 7-second segments of AF was defined as the DF variability (DFV) at each site. Mean ratio of the DF and its harmonics to the total power of the spectrum was defined as the organizational index (OI). Mean DFV was significantly lower in organized areas (OI > 1 SD above mean) than at all sites (0.34 ± 0.04 vs 0.46 ± 0.04 Hz; P < 0.001). When organized areas were ablated during wide-area circumferential ablation, AF organized in remote regions (LA appendage ΔOI ablated vs unablated: +0.21 [0.06-0.41] vs -0.04 [-0.14-0.05]; P = 0.005). CONCLUSIONS: At sites of organized activation, the activation frequency was also significantly more stable over time. This observation is consistent with the existence of focal sources, and inconsistent with a purely random activation pattern. Ablation of such regions is technically feasible, and was associated with organization of AF in remote atrial regions.