Prediction of second neurological attack in patients with clinically isolated syndrome using support vector machines

The aim of this study is to predict the conversion from clinically isolated syndrome to clinically definite multiple sclerosis using support vector machines. The two groups of converters and non-converters are classified using features that were calculated from baseline data of 73 patients. The data consists of standard magnetic resonance images, binary lesion masks, and clinical and demographic information. 15 features were calculated and all combinations of them were iteratively tested for their predictive capacity using polynomial kernels and radial basis functions with leave-one-out cross-validation. The accuracy of this prediction is up to 86.4% with a sensitivity and specificity in the same range indicating that this is a feasible approach for the prediction of a second clinical attack in patients with clinically isolated syndromes, and that the chosen features are appropriate. The two features gender and location of onset lesions have been used in all feature combinations leading to a high accuracy suggesting that they are highly predictive. However, it is necessary to add supporting features to maximise the accuracy. © 2013 IEEE

Lateral Wall Dysfunction Signals Onset of Progressive Heart Failure in Left Bundle Branch Block

International audienceOBJECTIVES: This study sought to investigate if contractile asymmetry between septum and left ventricular (LV) lateral wall drives heart failure development in patients with left bundle branch block (LBBB) and whether the presence of lateral wall dysfunction affects potential for recovery of LV function with cardiac resynchronization therapy (CRT). BACKGROUND: LBBB may induce or aggravate heart failure. Understanding the underlying mechanisms is important to optimize timing of CRT. METHODS: In 76 nonischemic patients with LBBB and 11 controls, we measured strain using speckle-tracking echocardiography and regional work using pressure-strain analysis. Patients with LBBB were stratified according to LV ejection fraction (EF) ≥50% (EF(preserved)), 36% to 49% (EF(mid)), and ≤35% (EF(low)). Sixty-four patients underwent CRT and were re-examined after 6 months. RESULTS: Septal work was successively reduced from controls, through EF(preserved), EF(mid), and EF(low) (all p < 0.005), and showed a strong correlation to left ventricular ejection fraction (LVEF; r = 0.84; p < 0.005). In contrast, LV lateral wall work was numerically increased in EF(preserved) and EF(mid) versus controls, and did not significantly correlate with LVEF in these groups. In EF(low,) however, LV lateral wall work was substantially reduced (p < 0.005). There was a moderate overall correlation between LV lateral wall work and LVEF (r = 0.58; p < 0.005). In CRT recipients, LVEF was normalized (≥50%) in 54% of patients with preserved LV lateral wall work, but only in 13% of patients with reduced LV lateral wall work (p < 0.005). CONCLUSIONS: In early stages, LBBB-induced heart failure is associated with impaired septal function but preserved lateral wall function. The advent of LV lateral wall dysfunction may be an optimal time-point for CRT

The Effects of Exercise Training in Patients With Persistent Dyspnea Following Pulmonary Embolism:A Randomized Controlled Trial

Bakgrunn Vedvarende dyspné, funksjonelle begrensninger og redusert livskvalitet (QoL) er vanlig etter lungeemboli (PE). Rehabilitering er et potensielt behandlingsalternativ , men den vitenskapelige dokumentasjonen er begrenset. Forskningsspørsmål Forbedrer et treningsbasert rehabiliteringsprogram treningskapasiteten hos PE-overlevere med vedvarende dyspné? Studiedesign og metoder Denne randomiserte kontrollerte studien ble utført ved to sykehus. Pasienter med vedvarende dyspné etter PE diagnostisert 6 til 72 måneder tidligere, uten kardiopulmonale komorbiditeter, ble randomisert 1:1 til enten rehabiliterings- eller kontrollgruppen. Rehabiliteringsprogrammet besto av to ukentlige økter med fysisk trening i 8 uker og en pedagogisk økt. Kontrollgruppen fikk vanlig pleie. Det primære endepunktet var forskjellen i Incremental Shuttle Walk Test mellom grupper ved oppfølging. Sekundære endepunkter inkluderte forskjeller i Endurance Shuttle Walk Test (ESWT), QoL (EQ-5D og lungeemboli-QoL spørreskjemaer) og dyspné (Shortness of Breath spørreskjema). Resultater Totalt 211 forsøkspersoner ble inkludert: 108 (51 %) ble randomisert til rehabiliteringsgruppen og 103 (49 %) til kontrollgruppen. Ved oppfølging presterte deltakerne fordelt på rehabiliteringsgruppen bedre på ISWT sammenlignet med kontrollgruppen (gjennomsnittlig forskjell, 53,0 m; 95 % KI, 17,7-88,3; P = 0,0035). Rehabiliteringsgruppen rapporterte bedre skårer på spørreskjemaet lungeemboli-kvalitet (gjennomsnittlig forskjell, –4 %; 95 % KI, –0,09 til 0,00; P = 0,041) ved oppfølging, men det var ingen forskjeller i generisk livskvalitet, dyspné. score, eller ESWT. Ingen uønskede hendelser oppsto under intervensjonen. Tolkning Hos pasienter med vedvarende dyspné etter PE hadde de som gjennomgikk rehabilitering bedre treningskapasitet ved oppfølging enn de som fikk vanlig behandling. Rehabilitering bør vurderes hos pasienter med vedvarende dyspné etter PE. Ytterligere forskning er imidlertid nødvendig for å vurdere optimal pasientvalg, tidspunkt, modus og varighet av rehabilitering.publishedVersio