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Background The relation between brain functional connectivity of patients with neuromyelitis optica spectrum disorder (NMOSD) and the degree of disability remains unclear. Objective Compare brain functional connectivity of patients with NMOSD to healthy subjects in resting-state functional MRI (rs-fMRI). Methods We compared the rs-fMRI connectivity in 12 NMOSD patients with 20 healthy subjects matched for age and sex. Graph theory analysis was used to quantify the role of each node using a set of metrics: degree, global efficiency, clustering and modularity. To summarize the abnormal connectivity profile of brain regions in patients compared to healthy subjects, we defined a hub disruption index κ. Results Concerning the global organization of networks in NMOSD, a small-world topology was preserved without significant modification concerning all average metrics. However, visual networks and the sensorimotor network showed decreased connectivity with high interindividual variability. The hub disruption index κ was correlated to the Expanded Disability Status Scale (EDSS). Conclusion These results demonstrate a correlation between disability according to the EDSS and neuronal reorganization using the rs-fMRI graph methodology. The conservation of a normal global topological structure despite local modifications in functional connectivity seems to show brain plasticity in response to the disability.

International audience; The application of Graph Theory to the brain connectivity patterns obtained from the analysis of neuroelectrical signals has provided an important step to the interpretation and statistical analysis of such functional networks. The properties of a network are derived from the adjacency matrix describing a connectivity pattern obtained by one of the available functional connectivity methods. However, no common procedure is currently applied for extracting the adjacency matrix from a connectivity pattern. To understand how the topographical properties of a network inferred by means of graph indices can be affected by this procedure, we compared one of the methods extensively used in Neuroscience applications (i.e. fixing the edge density) with an approach based on the statistical validation of achieved connectivity patterns. The comparison was performed on the basis of simulated data and of signals acquired on a polystyrene head used as a phantom. The results showed (i) the importance of the assessing process in discarding the occurrence of spurious links and in the definition of the real topographical properties of the network, and (ii) a dependence of the small world properties obtained for the phantom networks from the spatial correlation of the neighboring electrodes.

Nuclear imaging techniques like single-photon emission computed tomography (SPECT) and radionuclide angiography have wide applications in patients receiving a cardiac implantable electrical device (CIED), who cannot usually undergo cardiac magnetic resonance. Our aim was to provide an update of single-photon imaging clinical applications, with a specific focus on CIED recipients. SPECT imaging is commonly used in CIED patients to assess myocardial perfusion, but it can also be used to evaluate myocardial viability, which is an important predictor of LV function improvement by cardiac resynchronization therapy (CRT). Radionuclide angiography has shown higher temporal resolution and reproducibility than SPECT in the evaluation of cardiac function and dyssynchrony. Left ventricular dyssynchrony as assessed by radionuclide angiography with phase analysis may be reliably used for CRT patient selection and evaluation of CRT response. SPECT imaging with meta-iodo-benzyl-guanidine allows for cardiac sympathetic innervation examination, which may be used for prognostic stratification of heart failure patients and prediction of ventricular tachyarrhythmias. Finally, promising results in CIED infection diagnosis have been shown by SPECT with radiolabeled autologous white blood cells.

Aim: We carried out this study to investigate mid-term effects of cardiac resynchronization therapy (CRT) on right ventricular (RV) function and neurohormonal response, expressed by N-terminal pro-brain natriuretic peptide (NT-proBNP), in heart failure patients stratified by baseline RV ejection fraction (RVEF). Methods and Results: Thirty-six patients with nonischemic dilated cardiomyopathy underwent technetium-99m radionuclide angiography with bicycle exercise immediately after CRT implantation (during spontaneous rhythm and after CRT activation) and 3 months later. Plasma NT proBNP was assessed before implantation and after 3 months. At baseline, RVEF was impaired (≤35%) in 14 patients, preserved (>35%) in 22. At 3 months, RVEF improved during rest and exercise (P=.02) in patients with impaired RV function, while remaining unchanged in patients with preserved RV function. Rest and exercise RV dyssynchrony decreased in both groups at follow-up (P&nbsp

Although statins have proven efficacy in lowering lipids and improving survival in heart transplantation (HT) recipients, potential drug interactions may limit efficacy and reduce tolerability. This observational study explored the efficacy and tolerability of ezetimibe (10 mg/day) combined with simvastatin (10 or 20 mg/day) prescribed to HT recipients with intolerance to statins ( n = 11) or inadequate lipid control despite high-dose statins ( n = 14). Substantial reductions in lipid levels were apparent after 2 months (total cholesterol, −22%; low-density lipoproteins, −28%; triglycerides, −31%) and were maintained at 6 months. Reductions were significant in both subgroups of recipients; the vast majority (12 of 14, 85%) of recipients with a history of statins intolerance were able to tolerate ezetimibe plus low-dose simvastatin. This study provides suggestive evidence that treatment with ezetimibe plus low-dose simvastatin is well tolerated by HT recipients and may be effective for treatment of dyslipidemia in HT recipients with statins intolerance or resistance.

Information on the incidence of decompensation of chronic heart failure (CHF) in heart transplantation (HT) candidates eligible for prophylactic implantable cardioverter defibrillators (ICD) could provide insights into the influence of ICD on the timing for HT. Methods: We investigated the prevalence of candidates satisfying SCD-HeFT and MADIT-II criteria for prophylactic ICD among patients (n = 317) with CHF referred to our tertiary center for HT. In addition to standard clinical and laboratory assessments, baseline evaluation included two-dimensional standard transthoracic echocardiogram and 12-lead electrocardiogram. Results: At baseline, 19% of patients (n = 60) satisfied MADIT II criteria, and 58% (n = 185) fulfilled SCD-HeFT criteria. A total of 60% patients (n = 190) were eligible for prophylactic ICD implantation according to at least one set of criteria. Five-yr CHF decompensation-free survival was 68 ± 4% in patients eligible for prophylactic ICD (p = 0.003), (RR 2.5, 95% CI 1.35–4.63). Conclusions: SCD-HeFT could imply a threefold rise in ICD eligibility in tertiary settings. As ICD-eligible patients would likely remain at high risk of progressive ventricular dysfunction, strict follow-up should be considered extremely important to allow a timely referral for HT.

We investigated the diagnostic accuracy of (99m)Tc-3,3- diphosphono-1,2-propanodicarboxylic acid ((99m)Tc-DPD) scintigraphy for differentiation of monoclonal immunoglobulin light-chain (AL) and transthyretin (TTR)-related cardiac amyloidosis. BACKGROUND: Differential diagnosis between TTR-related and AL amyloidosis is often complex and time-consuming. METHODS: Patients under routine observation with TTR-related/AL systemic amyloidosis and echocardiographic evidence of cardiac involvement were studied with (99m)Tc-DPD scintigraphy. RESULTS: Patients with cardiac involvement of TTR-related (group A; n = 15) and AL (group B; n = 10) etiology were comparable for left ventricular mass and renal function. Heart and heart/whole-body tracer retention were significantly higher (p < 0.05) in group A as compared with group B and with 10 unaffected controls. At visual scoring, cardiac (99m)Tc-DPD uptake was present in all group A patients and absent in all group B patients; thus, using genotyping/immunohistochemistry as the reference technique, the accuracy of (99m)Tc-DPD scintigraphy for distinction of TTR-related and AL etiology was 100%. Cardiac (99m)Tc-DPD uptake was also absent among unaffected controls. Using echocardiography as the reference standard for recognition of cardiac involvement, sensitivity and specificity of scintigraphy were both 100% for group A patients; in group B, sensitivity was 0% and specificity was 100% (accu racy, 50%). Eleven patients with myocardial (99m)Tc-DPD uptake underwent (99m)Tc-methylene diphosphonate ((99m)Tc-MDP) scintigraphy; all patients showed a (99m)Tc-MDP myocardial visual score of 0. CONCLUSIONS: Etiology is a third major cause-in addition to type of organ-involved (soft-tissue/heart) and tracer type-of scintigraphic variability in cardiac amyloidosis. This is a highly relevant consideration for future studies. We conclude that (99m)Tc-DPD scintigraphy is a useful step in the workup of the differential diagnosis of TTR versus AL etiology in patients with documented cardiac amyloidosis.

In patients with heart failure and wide QRS complex, cardiac resynchronization therapy (CRT) is associated with improvement of symptoms and cardiac function. This study examined the effects of a 3-month period of CRT on left ventricular (LV) and right ventricular (RV) ejection fraction (EF) and on LV volumes, both at rest and during exercise. A CRT system was implanted in 15 patients with severe heart failure and wide QRS. Before implant and 3 months later, all patients underwent assessment of cardiac performance with equilibrium Tc 9 9 radionuclide angiography with imaging in the best septal left anterior oblique view. Exercise was performed on a bicycle ergometer. At 3 months, a significant improvement in New York Heart Association functional class was observed, and radionuclide angiography showed a significant decrease in LV volumes and a significant increase in LVEF at rest, as well as a significant increase in LVEF during exercise. The remodeling processes associated with CRT did not appear to include RV function, since RVEF did not improve, and changes in RVEF did not correlate with changes in LVEF, neither at rest nor during exercise.

Various modalities of cardiac pacing have been proposed in the past to improve hemodynamics, either directly or indirectly. Some of these are conventional ways of cardiac stimulation, others such as biventricular or left ventricular pacing, represent dedicated pacing techniques. Left ventricular and biventricular pacing are successfully applied in those patients with congestive heart failure who have conduction disturbances (i.e. left bundle branch block) as they correct the ensuing intra- and interventricular dyssynchrony. This is the reason why these pacing modalities are described as cardiac resynchronization therapy. According to the results of a series of studies, the cardiac resynchronization therapy seems to have a favourable clinical impact in terms of quality of life, morbidity and hospitalization rate. On-going and future studies should assess the impact of resynchronization therapy on overall mortality and its cost-effectiveness profile in specific subgroups of patients. Other open issues regard (i) the convenience of using biventricular pacing as a pacing-alone therapy or in combination with ventricular defibrillation capability, especially for potential candidates to heart transplantation, and (ii) the ways to identify properly the responders to resynchronization therapy.

Randomized trials showed that mTOR inhibitors prevent early development of cardiac allograft vasculopathy (CAV). However, the action of these drugs on CAV late after transplant is controversial, and their effectiveness for CAV prevention in clinical practice is poorly explored. In this observational study we included 143 consecutive heart transplant recipients who underwent serial intravascular ultrasound (IVUS), receiving either everolimus or mycophenolate as adjunctive therapy to cyclosporine. Ninety-one recipients comprised the early cohort, receiving IVUS at weeks 3-6 and year 1 after transplant, and 52 the late cohort, receiving IVUS at years 1 and 5 after transplant. Everolimus independently reduced the odds for early CAV (0.14 [0.01-0.77]; p = 0.02) but it did not appear to influence late CAV progression. High-dose statins were found to be associated with reduced CAV progression both early and late after transplant (p ≤ 0.05). Metabolic abnormalities, such as high triglycerides, were associated with late, but not with early CAV progression. By highlighting a differential effect of everolimus and metabolic abnormalities on early and late changes of graft coronary morphology, this observational study supports the hypothesis that everolimus may be effective for CAV prevention but not for CAV treatment, and that risk factors intervene in a time-dependent sequence during CAV development.

Background Predicting response to cardiac resynchronization therapy (CRT) remains a challenge. We evaluated the role of baseline QRS pattern to predict response in terms of improvement in biventricular ejection fraction (EF). Methods Consecutive patients (pts) undergoing CRT implantation underwent radionuclide angiography at baseline and at mid-term follow-up. The relationship between baseline QRS pattern and mechanical dyssynchrony using phase analysis was evaluated. Changes in left and right ventricular EF (LVEF and RVEF) were analyzed with regard to baseline QRS pattern. Results We enrolled 56 pts, 32 with left bundle branch block (LBBB), 4 with right bundle branch block (RBBB) and 20 with non-specific intraventricular conduction disturbance (IVCD). A total of 48 pts completed follow-up. LBBB pts had significantly greater improvement in LVEF compared to RBBB or non-specific IVCD pts (+9.6 ± 10.9% vs. +2.6 ± 7.6%, p = 0.003). Response (defined as ≥ 5% increase in LVEF) was observed in 68% of LBBB vs. 24% of non-specific IVCD pts (p = 0.006). None of the RBBB pts were responders. RVEF was significantly improved in LBBB (+5.0 ± 9.0%, p = 0.007), but not in non-specific IVCD and RBBB pts (+0.4 ± 5.8%, p = 0.76). At multivariate analysis, LBBB was the only predictor of LVEF response (OR, 7.45; 95% CI 1.80-30.94; p = 0.006), but not QRS duration or extent of mechanical dyssynchrony. Conclusions Presence of a LBBB is a marker of a positive response to CRT in terms of biventricular improvement. Pts with non-LBBB pattern show significantly less benefit from CRT than those with LBBB.

Background: Cyclosporine nephrotoxicity negatively impacts long-term outcome after heart transplantation (HT). We previously reported 1-year results from a randomized study showing that cyclosporine-lowering strategies based on everolimus or mycophenolate mofetil (MMF) are equally effective for reducing progression of renal dysfunction. It is unknown whether this efficacy could be maintained over the long term. Methods: Thirty-four recipients 1 to 4 years after HT and with 25 to 60 ml/min of creatinine clearance (CrCl) were randomized to everolimus with a very low dose (C0: 50 to 90 ng/ml, n = 17) or MMF with low dose of cyclosporine (C0: 100 to 150 ng/ml, n = 17). Follow-up was prolonged up to 3 years, and calculated CrCl was the main efficacy measure. Results: Cyclosporine was maintained at 70% and 30% lower than baseline in the everolimus and MMF arms, respectively, throughout the 3-year study period. CrCl remained stable in the everolimus patients (+7% from baseline; p = 0.7), but improved in the MMF patients (+20% from baseline; p < 0.01), with a trend toward improved values compared with everolimus patients (46 ± 12 vs 56 ± 15 ml/min; p = 0.06). Subgroup analysis revealed that baseline proteinuria markedly influenced the renal function response to everolimus: whereas in patients with baseline proteinuria CrCl significantly worsened (-20%; p = 0.04), it improved in those without (+15%; p = 0.03). Safety was comparable between the two study arms. Conclusions: Cyclosporine nephrotoxicity improved after a prolonged dose reduction in patients receiving MMF. The everolimus-based strategy provided a similar benefit only to patients without baseline proteinuria. While raising caution against the universal use of everolimus for kidney protection, our long-term results support the need for customized approaches in the management of drug toxicities in maintenance HT recipients.

Background: Statins are recommended in heart transplantation regardless of lipid levels. However, it remains unknown whether dosing should be maximized or adjusted toward a pre-defined cholesterol threshold. Methods: This pilot, randomized, open-label study compares an early maximal dose of fluvastatin (80 mg/day) with a strategy based on 20 mg/day subsequently titrated to target low-density lipoproteins (LDL) 0.5 mm, with numerical prevalence in the titrated-dosing arm (3 [12.5%] vs 1 [5%]; p = 0.3). Intimal volume increased in the titrated-dosing (p < 0.01) but not in the maximal-dosing arm (p = 0.1), which accordingly showed a higher prevalence of negative remodeling (p = 0.02). Conclusions: Despite being as effective as the titrated-dosing approach in achieving LDL

Background Cytomegalovirus (CMV) infection may influence the development of cardiac allograft vasculopathy (CAV). Prophylactic or preemptive administration of anti-CMV agents effectively prevents acute CMV manifestations. However, studies comparing allograft-related outcomes between these anti-CMV approaches are lacking. Herein we report a longitudinal observational study comparing CAV development between prophylactic and preemptive approaches. Methods The 1-year change in maximal intimal thickening (MIT) assessed by intravascular ultrasound at 1 and 12 months after heart transplantation (the major surrogate for late survival) was compared in groups of patients routinely assigned to a preemptive strategy (from November 2004 to October 2005; n = 21) or receiving valganciclovir prophylaxis (from November 2005 to October 2006; n = 19). CMV infection was monitored with pp65 antigenemia. Results The 1-year increase in MIT was significantly lower in patients receiving prophylaxis compared with those managed preemptively (0.15 ± 0.17 vs 0.31 ± 0.20 mm; p = 0.01). Prophylaxed recipients presented less frequently with MIT change ≥0.3 mm ( p = 0.03) and ≥0.5 mm ( p = 0.10) than those managed preemptively. Prophylaxis was also associated with later onset of CMV infection ( p = 0.01), lower peak CMV detection ( p p = 0.04). After adjusting for metabolic risk factors and other possible confounders, prophylaxis remained independently associated with lower risk for MIT change ≥0.3 mm (odds ratio=0.09, 95% confidence interval 0.01 to 0.93; p = 0.04). Conclusions Universal prophylaxis was associated with delayed onset of CMV infection, lower viral burden, reduced CMV disease/syndrome and less intimal thickening, as compared with a preemptive anti-CMV approach. Randomized studies are required to confirm the potential benefits of prophylaxis vs a preemptive approach in heart transplant recipients.

Background Folic acid therapy reduces homocysteine plasma levels, which seem to influence occurrence of cardiac allograft vasculopathy, but its effect on medium- or long-term prognosis after heart transplantation is unknown. Methods We analyzed 7-year outcome of 51 recipients randomized to receive 15 mg/day of methyltertrahydrofolate for 1 year after heart transplantation or standard therapy alone (originally, for intravascular ultrasound study of short-term cardiac allograft vasculopathy progression); recipients were observed for a further 5 to 6 years. Results Overall, 13 deaths occurred (six oncologic, five cardiovascular, two infective). Estimated 7-year survival was better in recipients randomized to folate (88%+/-6% vs. 61%+/-9%, P=0.04). After adjusting for age, pretransplant coronary artery disease, and hyperhomocysteinemia, posttransplant folic acid therapy was associated with lower mortality (relative risk [RR] 0.53, 95% confidence interval [CI] 0.25-0.97; P=0.036), apparently driven by reductions in both cancer-related and cardiovascular causes. Reduced mortality was marked in a high-risk subgroup comprising older recipients and patients transplanted because of coronary artery disease (RR 0.43, 95% CI 0.17-0.85) but not in the lower-risk subgroup (RR 1.11, 95% CI 0.22-5.61). Conclusions Although further studies are needed, it seems reasonable to suggest folate therapy to heart transplant recipients. It is possible that properties other than homocysteine reduction may provide antitumoral benefits.

While the beneficial effects of cardiac resynchronization therapy (CRT) on left ventricular (LV) systolic function have been demonstrated, no information is available regarding its effects on LV diastolic function during exercise. Using radionuclide angiography, we prospectively evaluated the effects of CRT on diastolic function at rest and during exercise in 15 patients consecutively referred for CRT. All patients underwent equilibrium Tc(99) radionuclide angiography with bicycle exercise performed (1) at baseline; (2) immediately after CRT implantation, in spontaneous rhythm and during CRT; and (3) after 3 months of biventricular stimulation. Diastolic function was assessed by measurements of peak filling rate (PFR). At baseline, activation of biventricular stimulation influenced PFR neither at rest (1.06 +/- 0.34 vs 1.07 +/- 0.50 mL/s during spontaneous rhythm, P = 0.9) nor during exercise (1.45 +/- 0.62 vs 1.33 +/- 0.48 mL/s, P = 0.3). At 3 months, improvements were observed in New York Heart Association functional class and systolic function. By contrast, no improvement in diastolic function was observed either at rest (PFR = 1.11 +/- 0.45 vs 1.07 +/- 0.50 mL/s in spontaneous rhythm at baseline, P = 0.6) or during exercise (1.23 +/- 0.50 vs 1.33 +/- 0.48 mL/s, P = 0.2). These observations indicate that the intermediate benefits conferred by CRT on LV systolic function at rest and during exercise were not accompanied by similar improvements in diastolic function.

It is unknown whether time-related changes of pulmonary hypertension (PH) have prognostic relevance in severe chronic heart failure (CHF).All CHF patients referred for follow-up from 1996 through 2003 were screened for this study. Eligibility depended on availability of a concomitant clinical, laboratory, electrocardiographic (ECG), echocardiographic and right-heart catheterization (RHC) assessment at index evaluation, as well as absence of pre-capillary PH.One hundred ninety-six patients (age 54 +/- 9 years; 27% women, 73% men; 50% in New York Heart Association [NYHA] Class III or IV) were included. PH at index evaluation was an independent predictor of acute heart failure or cardiovascular death (AHF/CD), with adjusted risk ratio (RR) = 2.30, 95% confidence interval (CI) 1.42 to 3.73 and p0.001. A pre-study (or =6 months) RHC was available for 174 of the 196 patients. Worsening of mean pulmonary artery pressure (mPAP) ofor =30% (a pre-specified cut-off corresponding to the 75th percentile of DeltamPAP%) provided prognostic information independent of all index-evaluation parameters (adjusted RR = 2.60, 95% CI 1.45 to 4.67, p = 0.001), and from time-related changes in the other hemodynamic parameters (por = 0.033).PH retains independent prognostic significance even after adjusting for a large set of clinical/laboratory/instrumental parameters. Furthermore, serial measurements of mPAP seem to provide additional prognostic information as compared with a single assessment. These findings indicate that serial evaluations of PAP may help identify a sub-set of high-risk CHF patients deserving a particularly close follow-up to facilitate timely indications for non-pharmacologic strategies, including (when appropriate) heart transplantation.

The problem of the definition and evaluation of brain connectivity has become a central one in neuroscience during the latest years, as a way to understand the organization and interaction of cortical areas during the execution of cognitive or motor tasks. Among various methods established during the years, the Directed Transfer Function (DTF), the Partial Directed Coherence (PDC) and the direct DTF (dDTF) are frequency-domain approaches to this problem, all based on a multivariate autoregressive modeling of time series and on the concept of Granger causality. In this paper we propose the use of these methods on cortical signals estimated from high resolution EEG recordings, a non invasive method which exhibits a higher spatial resolution than conventional cerebral electromagnetic measures. The principle contribution of this work are the results of a simulation study, testing the capability of the three estimators to reconstruct a connectivity model imposed, with a particular eye on the capability to distinguish between direct and indirect causality. An application to high resolution EEG recordings during a foot movement is also presented.