The Usefulness of the CHA2DS2-VASc Score to Predict Outcomes in Patients with Infective Endocarditis.

Introduction: Despite diagnostic and therapeutic advances, infective endocarditis (IE) is still associated with high mortality rates. Currently, there are no good prognostic tools for the risk assessment of patients with IE. The CHA2DS2-VASc score, used to estimate the risk of ischemic stroke in patients with non-valvular atrial fibrillation (AF), has been shown to be a powerful predictor of stroke and death in patients without known AF associated with other cardiovascular conditions. Objective: We aimed to evaluate the usefulness of the CHA2DS2-VASc score as a prognostic tool in a population of patients with IE. Methods: The Rabin Medical Center Endocarditis Team (RMCET) registry is a retrospective cohort of all patients evaluated at our center due to acute or sub-acute bacterial endocarditis. The CHA2DS2-VASc score was extracted for all patients. All-cause mortality was depicted for all patients. Results: The cohort included 330 patients with a mean age of 65.2 ± 14.7 years (70% men). During a median follow-up of 24 months [IQR 4.7-48.6], 121 (36.7%) patients died. The median CHA2DS2-VASc score was 3, and any score above 2 was associated with increased overall mortality (50.8% vs. 19.9%, p < 0.001). A multivariate model incorporating important confounders not included in the CHA2DS2-VASc model showed consistent results with a risk increase of 121% for the higher CHA2DS2-VASc score groups (HR 2.21 [CI 1.12-4.39], p = 0.023). Conclusions: IE currently has no good risk stratification models for clinical practice. The CHA2DS2-VASc score might serve as a simple and available tool to stratify risk among patients with IE.

Age-related differences in the effect of a perceived threat to stability on postural control.

BACKGROUND: Studies indicate that the strategy for postural control may be affected by psychological factors, and that young adults respond to perceived threat to stability by increasing their ankle stiffness. The objective of this study was to compare the postural control strategy adopted by young and old adults when faced with postural threat induced by manipulating surface height. METHODS: Sixty elderly (mean age 77.5+/-4.4 years) and 20 young volunteers (mean age 21.5+/-3.7 years) participated in the study. Movement of the center of pressure (COP) was recorded for 60 seconds with a portable force-plate, as participants stood with eyes open and closed, both at ground level and 85 cm above ground level. Analysis of variance and Tukey-Kramer tests were conducted to determine the effects of age, postural threat, and vision on mean power frequency (MPF), on amplitude variability both in the anterior-posterior (AP) and medio-lateral (ML) directions, and on mean COP sway velocity, with the significance level set at p=.05. RESULTS: Postural threat did not affect COP measures for the young adults, whereas it induced greater changes in MPF in the AP and ML directions in the elderly participants. A similar trend was observed in the elderly group for amplitude variability in the ML direction and for mean COP sway velocity. CONCLUSIONS: In comparison with young adults, elderly adults tend to have an exaggerated postural response to conditions that are perceived as threatening to stability. This response involves primarily increases in MPF, with limited compensatory decreases in amplitude variability observed only in the ML direction.

Gait characteristics of elderly people with a history of falls: a dynamic approach.

BACKGROUND AND PURPOSE: This study investigated changes in the kinematics of elderly people who experienced at least one fall 6 months prior to data collection. The authors hypothesized that, in order to decrease variability of walking, people with a history of falls would show different kinematic adaptations of their walking patterns compared with elderly people with no history of falls. SUBJECTS AND METHODS: Twenty-one elderly people who had fallen within the previous 6 months ("fallers"; mean age=72.1 years, SD=4.9) and 27 elderly people with no history of falls ("nonfallers"; mean age=73.8 years, SD=6.4) walked at their preferred stride frequency (STF) as treadmill speed was gradually increased (from 0.18 m/s to 1.52 m/s) and then decreased in steps of 0.2 m/s. Gait parameter measurements were recorded, and statistical analysis was applied using walking speed and STF as independent variables. RESULTS: Fifty-seven percent of the fallers were unable to walk at the fastest speed, whereas all nonfallers walked comfortably at all walking speeds. Although the fallers showed significantly greater STF, smaller stride lengths, smaller center-of-mass lateral sway, and smaller ankle plantar flexion and hip extension during push-off, they showed increased variability of kinematic measures in their coordination of walking compared with the nonfallers. DISCUSSION AND CONCLUSION: Although the fallers' adaptations were expected to reduce variability in the coordination of walking, they showed less stable gait patterns (ie, greater variability) compared with the nonfallers. Increased variability of walking patterns may be an important gait risk factor in elderly people with a history of falls.

Spectral EMG changes in vastus medialis muscle following short range of motion isokinetic training.

This study was aimed at exploring the carryover effect of short range of motion (RoM) isokinetic conditioning on vastus medialis (VM) motor unit recruitment (MUR) across the full RoM. Fifty-five women were randomly assigned to one of four groups: G1 (n = 14) and G2 (n = 14) trained concentrically at 30 and 90 degrees /s, respectively whereas G3 (n = 13) and G4 (n = 14) trained similarly but using the eccentric mode. All 4 groups trained within 30-60 degrees of knee flexion. The training protocol consisted of 4 sets of 10 maximal repetitions, 3 times a week for 6 weeks. sEMG was recorded from the VM for analysis of mean frequency of the EMG power spectrum prior to the training period and 2 days after its termination. The EMG assessments took place during dynamic contractions within 3 angular RoM's: 85-60 degrees (R1), 60-30 degrees (R2) and 30-5 degrees (R3). In addition MUR was evaluated during isometric contractions at 10 degrees , 45 degrees and 80 degrees . Significant increases were observed in the MUR at R1, R2, and R3 during dynamic contractions as well as in all 3 angles during isometric contractions. These findings applied equally regardless of the mode of contraction and motion speed during training. The fact that MUR increased significantly within untrained RoM's may point out to the potential benefits of short RoM conditioning, particularly in those cases where, during specific phases of rehabilitation, a wider RoM may be contraindicative.

Transferability of strength gains from limited to full range of motion.

PURPOSE: This study was aimed at exploring the transferability of short range of motion (RoM) isokinetic conditioning on quadriceps performance inside and outside the trained range. METHODS: Fifty-five women were randomly assigned to one of four groups: G1 (N = 14) and G2 (N = 14) trained concentrically at 30 and 90degrees x s(-1), respectively, whereas G3 (N = 13) and G4 (N = 14) trained similarly but using the eccentric mode. All four groups trained within 30-60degrees of knee flexion. The training paradigm consisted of 4 sets of 10 maximal repetitions, 3x wk(-1) for a total period of 6 wk. Before the training period and 2 d after its termination, the isokinetic work output (Wisk) was assessed within three angular RoM: 85-60degrees (R1), 60-30degrees (R2), and 30-5degrees (R3). Isometric peak extension moment (PM) and rate of force development (RFD) were evaluated at 10degrees, 45degrees and 80degrees. RESULTS: Significant increases were observed in the isometric output (at all three angles), Wisk (in R1 and R2), and the RFD (45degrees). The PM increased significantly more in G3 and G4 compared with G1 and G2, evidencing specificity of contraction mode. CONCLUSION: These findings point out to the potential benefits of short RoM conditioning, particularly in those cases where, during specific phases of rehabilitation, a wider RoM may be contraindicative.