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991.
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VT Ablation Treatment of Last Resort. Introduction: Despite advances in ablation of ventricular tachycardia (VT), recognized toxicity of amiodarone, and potential harm of implantable cardioverter defibrillator (ICD) shocks, there appears to be reluctance to pursue catheter ablation. Methods and Results: We tested the hypothesis that patients with structural heart disease and VT are referred late for ablation and may have worse outcomes as a result. Consecutive patients with VT and structural heart disease referred to a single center, between January 2008 and April 2009 were studied. Patients with prior VT ablations were excluded. Late referrals were defined as those with 2 or more episodes of VT, separated by at least 1 month. Ninety‐eight consecutive patients were analyzed. Ninety‐six percent of patients had an ICD implanted prior to ablation, 58% were in VT storm and 67% taking ≥400 mg daily of amiodarone or amiodarone intolerant (10%). Thirty‐six patients fit the definition of early referral and 62 late. Overall acute procedural success was achieved in 89%. Amiodarone dose decreased from a mean and median of 559 and 400 mg daily preablation to 98 and 0 postablation (P < 0.01). Mean and median VT episodes decreased from 17 and 6 in the month preceding ablation to 1 and 0 in the 6 months following ablation (P < 0.01). In Kaplan–Meier analysis, the early referral group had superior 1‐year VT free survival (P = 0.01). Conclusions: VT ablation is frequently reserved for patients receiving recurrent ICD shocks despite high dose amiodarone. Stronger consideration should be given to earlier referral for VT ablation in patients with structural heart disease. (J Cardiovasc Electrophysiol, Vol. 22, pp. 1123‐1128, October 2011)  相似文献   
994.

Background

Exercise performance improvement after training in heart failure (HF) can be due to central or peripheral changes.

Methods and Results

In 70 HF stable patients we measured peak VO2 and cardiac output (CO, inert gas rebreathing technique) and calculated arteriovenous O2 differences (a-v O2diff) before and after an 8-week training program. Peak VO2 changed from 1111 ± 403 mL/minute to 1191 ± 441 (P < .001), peak workload from 68 ± 29 watts to 76 ± 32 (P < .0001), peakCO from 6.6 ± 2.2 L/minute to 7.3 ± 2.5 (P < .0001), and peak a-v O2diff from 17.5 ± 5.1 mL/100 mL to 16.6 ± 4.1 (P = .081). Changes in peak CO and a-v O2diff allowed to identify 4 behaviors: group 1: (n = 15) reduction in peak CO and increase in a-v O2diff (peak VO2 unchanged, peak workload +9.5%); group 2: (n = 16) both peak CO and a-v O2diff increased as well as peak VO2 (23%) and workload (18%); group 3: (n = 4) peak CO and a-v O2diff reduced as well as peak VO2 (-18%) and workload (-5%); group 4: (n = 35) peak CO increased with a-v O2diff reduced (increase in peak VO2 by 5.5 and workload by 8.4%).

Conclusions

Exercise training improves peakVO2 by increasing CO with unchanged a-v O2diff. A reduction after training of a-v O2diff with an increase in CO is frequent (50% of cases), is suggestive of blood flow redistribution and, per se, not a sign of reduced muscle performance been associated with improved exercise capacity.  相似文献   
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The purpose of this study was to evaluate the efficacy of an intervention to assist HIV positive men who have sex with men (MSM) in forming and executing strategies for the disclosure of their serostatus to their families of origin. Results indicate that the intervention was successful in assisting men with the primary outcome of disclosure. Participants reported no regret with disclosures occurring during the intervention and follow-up period. Effects on secondary outcomes including family functioning, depression, loneliness, and perceived social support were inconclusive. Implications, refinements of this intervention, and suggestions for future disclosure research are provided.  相似文献   
996.
Epilepsy self-management interventions have been investigated with respect to health care needs, medical adherence, depression, anxiety, employment, and sleep problems. Studies have been limited in terms of representative samples and inconsistent or restricted findings. The direct needs assessment of patients with epilepsy as a basis for program design has not been well used as an approach to improving program participation and outcomes. This study investigated the perceived medical and psychosocial problems of adults with epilepsy, as well as their preferences for self-management program design and delivery format. Results indicated a more psychosocially challenged subgroup of individuals with significant depressive and cognitive complaints. A self-management program that involves face-to-face individual or group meetings led by an epilepsy professional and trained peer leader for 60 minutes weekly was preferred. Six to eight sessions focused on diverse education sessions (e.g., managing disability and medical care, socializing on a budget, and leading a healthy lifestyle) and emotional coping strategies delivered on weeknights or Saturday afternoons were most highly endorsed. Emotional self-management and cognitive compensatory strategies require special emphasis given the challenges of a large subgroup.  相似文献   
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ObjectiveLow-frequency repetitive transcranial magnetic stimulation (rTMS) is emerging as a therapeutic tool in epilepsy. In recent years, several open-label trials have shown an encouraging reduction in seizure frequency in patients with epilepsy. However, the data from controlled trials are mixed with respect to antiepileptic rTMS efficacy, and the field would benefit from further carefully controlled trials. Prior to initiating new trials, it is important assess the magnitude of the placebo effect of presently used sham rTMS methods.MethodsWe systematically analyzed individual subject data from three placebo-controlled trials and measured the placebo effect at follow-up intervals of 2, 4, and 8 weeks after sham rTMS treatment. Given the relatively small subgroup sample size, placebo condition data were pooled for analysis.ResultsThree methods for sham rTMS were employed in the reviewed studies: (1) coil positioning orthogonal to the scalp, (2) a spring-loaded sham coil, and (3) a double active-sham coil. The placebo response overall was consistently low across follow-up intervals, both for median change in seizure frequency (Kruskal–Wallis, P > 0.4, df = 2) and for responder (defined as ≥ 50% seizure frequency reduction) rate (Fisher's exact rest, P > 0.9, df = 2). The aggregate effect of the placebo condition was a 0–2% median seizure reduction rate and a responder rate of 16–20%.ConclusionWe anticipate that these data will contribute to future power analysis as well as selection and design of sham rTMS methods for controlled rTMS trials.  相似文献   
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999.

OBJECTIVE

The objective of the study was to prospectively assess the association between lactation duration and incidence of the metabolic syndrome among women of reproductive age.

RESEARCH DESIGN AND METHODS

Participants were 1,399 women (39% black, aged 18–30 years) in the Coronary Artery Risk Development in Young Adults (CARDIA) Study, an ongoing multicenter, population-based, prospective observational cohort study conducted in the U.S. Women were nulliparous and free of the metabolic syndrome at baseline (1985–1986) and before subsequent pregnancies, and reexamined 7, 10, 15, and/or 20 years after baseline. Incident metabolic syndrome case participants were identified according to National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria. Complementary log-log models estimated relative hazards of incident metabolic syndrome among time-dependent lactation duration categories by gestational diabetes mellitus (GDM) adjusted for age, race, study center, baseline covariates (BMI, metabolic syndrome components, education, smoking, physical activity), and time-dependent parity.

RESULTS

Among 704 parous women (620 non-GDM, 84 GDM), there were 120 incident metabolic syndrome case participants in 9,993 person-years (overall incidence rate 12.0 per 1,000 person-years; 10.8 for non-GDM, 22.1 for GDM). Increased lactation duration was associated with lower crude metabolic syndrome incidence rates from 0–1 month through >9 months (P < 0.001). Fully adjusted relative hazards showed that risk reductions associated with longer lactation were stronger among GDM (relative hazard range 0.14–0.56; P = 0.03) than non-GDM groups (relative hazard range 0.44–0.61; P = 0.03).

CONCLUSIONS

Longer duration of lactation was associated with lower incidence of the metabolic syndrome years after weaning among women with a history of GDM and without GDM, controlling for preconception measurements, BMI, and sociodemographic and lifestyle traits. Lactation may have persistent favorable effects on women''s cardiometabolic health.Lactation has favorable effects on cardiometabolic risk factors in women with and without a history of gestational diabetes mellitus (GDM), a strong predictor of type 2 diabetes (1,2) and the metabolic syndrome after pregnancy (3). In the general population, lactating compared with nonlactating women exhibit a less atherogenic lipid profile (4) and lower blood glucose and insulin concentrations (5). Consistent with these findings, lactating women with recent GDM experience lower fasting plasma glucose and insulin levels, higher plasma HDL cholesterol levels, and 50% lower prevalence of type 2 diabetes at 12–16 weeks postpartum (6,7).Yet, few studies have investigated whether lactation''s favorable effects on cardiometabolic risk factors persist after weaning to protect women against future disease. The only study, to our knowledge, to measure changes from preconception to after weaning reported 6-mg/dl higher average HDL cholesterol levels among women who lactated for ≥3 months versus <3 months independent of preconception plasma HDL cholesterol levels and weight gain (8). Epidemiologic studies have reported weak to modest protective associations between lactation and disease risk in midlife to late life, including lower prevalence of the metabolic syndrome (9,10) or cardiovascular risk factors (11) and lower incidence of myocardial infarction (12) and type 2 diabetes (13). Yet, evidence is lacking that directly links risk factor changes that persist after weaning to subsequent disease onset, because disease status and lactation history were ascertained decades after pregnancy, and preconception and/or postweaning risk factor measurements were not available (913). Other limitations include classification of outcomes via self-report only (1113), and failure to account for mediating or confounding effects of lifestyle habits during the reproductive years. Lastly, lactation duration in relation to disease risk has not been examined separately among women with a history of GDM, with the exception of one study reporting a null association with incident diabetes (13).To our knowledge, studies have never examined lactation and incidence of the metabolic syndrome, or variation in disease risk by GDM status. To address these gaps, we prospectively examined whether increasing duration of lactation was associated with lower incidence of the metabolic syndrome during a 20-year period among women of childbearing age. We examined incidence rates for GDM and non-GDM pregnancies and controlled for preconception risk factor levels, sociodemographics, and follow-up behavioral attributes.  相似文献   
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