Relationship between infarct tissue characteristics and left ventricular remodeling in patients with versus without early revascularization for acute myocardial infarction as assessed with contrast-enhanced cardiovascular magnetic resonance imaging

Left ventricular (LV) remodeling following myocardial infarction (MI) is the result of complex interactions between various factors, including presence or absence of early revascularization. The impact of early revascularization on the relationship between infarct tissue characteristics and LV remodeling is incompletely known. Therefore, we investigated in patients with versus without successful early revascularization for acute MI potential relations between infarct tissue characteristics and LV remodeling with contrast-enhanced (CE) cardiovascular magnetic resonance (CMR). Patients with versus without successful early revascularization underwent CE-CMR for tissue characterization and assessment of LV remodeling including end-diastolic and end-systolic volumes, LV ejection fraction, and wall motion score index (WMSI). CE-CMR images were analyzed for infarct tissue characteristics including core-, peri- and total-infarct size, transmural extent, and regional scar scores. In early revascularized patients (n = 46), a larger area of infarct tissue correlated significantly with larger LV dimensions and a more reduced LV function (r = 0.39-0.68; all P ≤ 0.01). Multivariate analyses identified peri-infarct size as the best predictor of LV remodeling parameters (R2 = 0.44-0.62). In patients without successful early revascularization (n = 47), there was no correlation between infarct area and remodeling parameters; only peri-infarct size versus WMSI (r = 0.33; P = 0.03) and transmural extent versus LVEF (r = -0.27; P = 0.07) tended to be related. A correlation between infarct tissue characteristics and LV remodeling was found only in patients with early successful revascularization. Peri-infarct size was found to be the best determinant of LV remodeling. Our findings stress the importance of taking into account infarct tissue characteristics and success of revascularization when LV remodeling is studie

Infarct tissue characterization in implantable cardioverter-defibrillator recipients for primary versus secondary prevention following myocardial infarction: a study with contrast-enhancement cardiovascular magnetic resonance imaging

Knowledge about potential differences in infarct tissue characteristics between patients with prior life-threatening ventricular arrhythmia versus patients receiving prophylactic implantable cardioverter-defibrillator (ICD) might help to improve the current risk stratification in myocardial infarction (MI) patients who are considered for ICD implantation. In a consecutive series of (ICD) recipients for primary and secondary prevention following MI, we used contrast-enhanced (CE) cardiovascular magnetic resonance (CMR) imaging to evaluate differences in infarct tissue characteristics. Cine-CMR measurements included left ventricular end-diastolic and end-systolic volumes (EDV, ESV), left ventricular ejection fraction (LVEF), wall motion score index (WMSI), and mass. CE-CMR images were analyzed for core, peri, and total infarct size, infarct localization (according to coronary artery territory), and transmural extent. In this study, 95 ICD recipients were included. In the primary prevention group (n = 66), LVEF was lower (23 ± 9 % vs. 31 ± 14 %; P < 0.01), ESV and WMSI were higher (223 ± 75 ml vs. 184 ± 97 ml, P = 0.04, and 1.89 ± 0.52 vs. 1.47 ± 0.68; P < 0.01), and anterior infarct localization was more frequent (P = 0.02) than in the secondary prevention group (n = 29). There were no differences in infarct tissue characteristics between patients treated for primary versus secondary prevention (P > 0.6 for all). During 21 ± 9 months of follow-up, 3 (5 %) patients in the primary prevention group and 9 (31 %) in the secondary prevention group experienced appropriate ICD therapy for treatment of ventricular arrhythmia (P < 0.01). There was no difference in infarct tissue characteristics between recipients of ICD for primary versus secondary prevention, while the secondary prevention group showed a higher frequency of applied ICD therapy for ventricular arrhythmia.\u

O efeito da descontinuação dos corticóides inalados em doentes com Doença Pulmonar Obstrutiva Crónica — O estudo COPE

RESUMO: Os autores desenharam um estudo duplamente cego para investigar o efeito da descontinuação do propionato de fluticasona (PF) nas exacerbações e qualidade de vida em doentes com DPOC (estudo COPE).Durante 4 meses, 244 doentes com DPOC foram medicados com propionato de fluticasona (1000 (g /dia).A selecção dos doentes baseou se em critérios clínicos e funcionais e idade compreendida entre os 40 e os 75 anos. Após este período de tempo, 123 doentes mantiveram o tratamento com PF e 121 doentes receberam placebo durante 6 meses. As visitas de controlo ocorreram aos 3 e 6 meses, tendo os doentes sido avaliados do ponto de vista funcional e clínico. Os critérios analisados no estudo foram o número, gravidade e intervalo de tempo entre as exacerbações, a qualidade de vida (questionário respiratório de St Georgeâs), parâmetros funcionais respiratórios (espirometria) e tolerância ao esforço (prova de 6 minutos de marcha standardizada).Na análise dos resultados, os autores demonstraram que no grupo medicado com PF, 47% dos doentes sofreram pelo menos uma agudização, em contraste dos 57 % do grupo placebo. No grupo placebo, 21 % dos doentes apresentaram exacerbações recorrentes e rápidas, ao contrário dos 6% de doentes medicados com PF. Em termos de qualidade de vida, uma diferença significativa ocorreu também entre os 2 grupos, a nível do score total, actividade e sintomas.Não se verificaram diferenças na prova de marcha entre os 2 grupos avaliados. O estudo funcional mostrou uma diferença significativa de 38 ml de VEMS pós-broncodilatação, a favor do grupo medicado com FP.Este estudo indica que a descontinuação de PF em doentes com DPOC está associada a um mais rápido início e recorrência de agudização, bem como uma deterioração maior da qualidade de vida. COMENTÃRIO: Estima-se que a DPOC constitua a 5.ª doença mais frequente e a 4.ª causa de morte a nível mundial.Não existindo cura para esta doença, a terapêutica assenta fundamentalmente na broncodilatação e na evicção tabágica.Sabe se que apesar de a DPOC ser uma doença inflamatória crónica das vias aéreas, os corti cóides inalados (CI) não modificam o declínio mais acelerado do VEMS constatado na DPOC.Múltiplos estudos foram efectuados tendo como um dos objectivos determinar a validade da utilização de CI na DPOC, dos quais se salienta:O estudo EUROSCOP revela eficácia reduzida e transitória do budesonido; o estudo ISOLDE mostrou uma pequena redução no declínio do VEMS, um menor número de exacerbações e score sintomático, em doentes com DPOC grave tratados com fluticasona e o estudo COPENHAGEN não demonstrou qualquer beneficio do budesonido na DPOC ligeira e moderada.O projecto GOLD considera os CI como fármacos de 2.ª linha no tratamento da DPOC, mas refere também uma melhoria sintomática, uma redução no número e gravidade das exacerbações e melhoria da qualidade de vida.Este estudo vem exactamente reforçar o efeito benéfico dos CI em doentes com DPOC a nível da qualidade de vida e frequência e gravidade das agudizações, assim como o agravamento destes parâmetros após a suspensão dos CI. Palavras-chave: Corticóides inalados, DPOC, Qualidade de vida, Exacerbaçã

Models of OH Maser Variations in U Her

Arecibo spectra of the mainline OH maser emission from U Her over more than a decade show variations of the OH emission over these time scales. These observations are combined with high spatial resolution VLBA maps to investigate the causes of the variations in the velocities of the maser components. Global properties of the dust shell, such as accelerations, variations in the pump and shell-wide magnetic field changes are examined as possibilities, and eliminated. A possible solution to the problem involving plasma turbulence and the local magnetic field is introduced, and the relevant time scales of the turbulence are calculated. The turbulent velocity field yields time scales of the turbulence are calculated. The turbulent velocity field yields time scales that are too long (of order centuries), while the turbulent magnetic field produces variations on appropriate time scales of a few years. A line-of-sight model of the turbulence is developed and investigated. The complete exploration of this solution requires extensive theoretical and observational work. Possible avenues of investigation of the plasma turbulence model are presented.Comment: 23 pages, 17 figures, ApJ: accepted Sept, 199

Measuring Patient-Reported Outcomes Adaptively: Multidimensionality Matters!

As there is currently a marked increase in the use of both unidimensional (UCAT) and multidimensional computerized adaptive testing (MCAT) in psychological and health measurement, the main aim of the present study is to assess the incremental value of using MCAT rather than separate UCATs for each dimension. Simulations are based on empirical data that could be considered typical for health measurement: a large number of dimensions (4), strong correlations among dimensions (.77-.87), and polytomously scored response data. Both variable- (SE <.316, SE <.387) and fixed-length conditions (total test length of 12, 20, or 32 items) are studied. The item parameters and variance–covariance matrix Φ are estimated with the multidimensional graded response model (GRM). Outcome variables include computerized adaptive test (CAT) length, root mean square error (RMSE), and bias. Both simulated and empirical latent trait distributions are used to sample vectors of true scores. MCATs were generally more efficient (in terms of test length) and more accurate (in terms of RMSE) than their UCAT counterparts. Absolute average bias was highest for variable-length UCATs with termination rule SE <.387. Test length of variable-length MCATs was on average 20% to 25% shorter than test length across separate UCATs. This study showed that there are clear advantages of using MCAT rather than UCAT in a setting typical for health measurement

Identifying key domains of health-related quality of life for patients with Chronic Obstructive Pulmonary Disease: the patient perspective

Background Numerous instruments are available to measure health-related quality of life (HRQoL) in patients with Chronic Obstructive Pulmonary Disease (COPD), covering a wide array of domains ranging from symptoms such as dyspnea, cough and wheezing, to social and emotional functioning. Currently no information or guide is available yet to aid the selection of domains for a particular study or disease population. The aim of this paper is to identify which domains of HRQoL are most important with respect to COPD, from the patient perspective. Methods Twenty-one Dutch patients with COPD were asked to describe important domains impacted by COPD freely; second, they were presented with cues (domains from the Patient-Reported Outcomes Measurement Information System (PROMIS) framework) and were asked to select the domains that were most relevant to them. During the interview, the patients were asked to indicate in which way the selected domains impact their lives. Both the answers to the open question, and the patient statements motivating nomination of PROMIS domains were coded into themes. Results The most relevant (sub)domains of HRQoL for patients with COPD were: physical health (fatigue, physical functioning), social health (instrumental support, ability to participate in social roles and activities, companionship, and emotional support), and coping with COPD. Conclusion We identified which domains of HRQoL are most important to patients with COPD. One of these (coping with COPD) is not explicitly covered by PROMIS, or by traditional questionnaires that are used to measure HRQoL in COPD