Stability of the ECG features of complete right bundle branch block over time: a methodological study for implementation in research and clinical practice

Since research is concentrated to a large extent on patients with left bundle branch block, we aimed at evaluating the hypothesis that measurements of certain intervals and other characteristics of the ECG may change over time in patients with right bundle branch block (RBBB), and to design a model, which could be implemented in research and clinical practice, irrespective of the specific ECG features present. The duration of the QRS complex, QT, QTc, and PR intervals, the frontal QRS axis, the heart rate and the presence of hemiblocks, atrioventricular blocks, and atrial fibrillation were compared in the 1st and last of all available ECGs for each patient. Also, a subgroup of patients who had a ventricular aneurysm (VA) was compared with the remaining patients, with respect to the above variables. This longitudinal analysis included all of the patients with RBBB followed in our Cardiology Clinic. There were no significant changes in the ECG variables from the two ECGs recorded 487.6 +/- 410.1 (range 0-1,476) days apart, in the two comparisons carried out in 151 patients with RBBB. Comparison of the above-described ECG intervals and characteristics of patients with RBBB were found to be stable over the time course of the investigation. This methodological study is presented as a model to be used serially and prospectively in research and clinical practice for the follow-up of patients with bundle branch block, VA, dilated cardiomyopathy, congestive heart failure, or those considered for cardiac resynchronization therapy.     

Logistic regression models for predicting physical and mental health-related quality of life in rheumatoid arthritis patients

The aim of this work was to develop two logistic regression models capable of predicting physical and mental health related quality of life (HRQOL) among rheumatoid arthritis (RA) patients. In this cross-sectional study which was conducted during 2006 in the outpatient rheumatology clinic of our university hospital, Short Form 36 (SF-36) was used for HRQOL measurements in 411 RA patients. A cutoff point to define poor versus good HRQOL was calculated using the first quartiles of SF-36 physical and mental component scores (33.4 and 36.8, respectively). Two distinct logistic regression models were used to derive predictive variables including demographic, clinical, and psychological factors. The sensitivity, specificity, and accuracy of each model were calculated. Poor physical HRQOL was positively associated with pain score, disease duration, monthly family income below 300 US$, comorbidity, patient global assessment of disease activity or PGA, and depression (odds ratios: 1.1; 1.004; 15.5; 1.1; 1.02; 2.08, respectively). The variables that entered into the poor mental HRQOL prediction model were monthly family income below 300 US$, comorbidity, PGA, and bodily pain (odds ratios: 6.7; 1.1; 1.01; 1.01, respectively). Optimal sensitivity and specificity were achieved at a cutoff point of 0.39 for the estimated probability of poor physical HRQOL and 0.18 for mental HRQOL. Sensitivity, specificity, and accuracy of the physical and mental models were 73.8, 87, 83.7% and 90.38, 70.36, 75.43%, respectively. The results show that the suggested models can be used to predict poor physical and mental HRQOL separately among RA patients using simple variables with acceptable accuracy. These models can be of use in the clinical decision-making of RA patients and to recognize patients with poor physical or mental HRQOL in advance, for better management.     

Effects of visual and cognitive interference on joint contributions in perturbed standing: a temporal and spectral analysis

Postural balance requires using joint strategies which may be changed from normal conditions by interfering with the sensory information. The goal of the present study was to quantitatively evaluate the role of the joint mechanisms during perturbed stance. Visual and cognitive interference was imposed to sixteen healthy young males under rotational toes-down or up perturbations. Power spectral analysis was employed to distinguish the joint contribution and their in- or out-phase co-works. Results showed that addition of cognitive loads reduce the stability by increasing the center of mass (CoM) power to three times greater. Besides the CoM, the knee and hip powers were also significantly enhanced by the cognitive loads (p?<?.004), but the ankle was not influenced by cognition involvement (p?>?.05). Elimination of the vision had lower effect on the time and spectral functions of the knee and hip while the ankle rotations were increased due to the lack of visual feedback (p?=?.001). The toes-down perturbations resulted in more prominent contribution of the knee while the toes-up evoked the hip joint to keep the balance more than the other joints. Addition of the cognitive loads hindered the reactions of the joint mechanisms and vision caused more conservative responses of the joints.     

Application of CMAP scan for the evaluation of patients with chronic inflammatory demyelinating polyneuropathy: a prospective study

AimsWe aimed to assess the compound muscle action potential (CMAP) scan in the follow-up of chronic inflammatory demyelinating polyneuropathy (CIDP) patients and investigate the correlation of CMAP scan parameters with functional and standard electrodiagnostic tests.MethodsWe evaluated four parameters of abductor pollicis brevis (APB) CMAP scan (i.e., step numbers, step percentage, S10, S90), functional measures (e.g., Medical Research Council Sum Scores), and electrodiagnostic tests, including nerve conduction study (NCS) and motor NCS of the median nerve in the baseline and after six months of treatment.ResultsTwenty patients completed baseline clinical and electrodiagnostic studies. However, sixteen patients completed the follow-up study. The median of step numbers at baseline was 3.5 (2–4.2), which decreased to 2.5 (0–3) (p = 0.005). After the treatment, step percentage reduced from 28.6 (23.9–38.7) to 13.4 (0–23.6) (p = 0.001). The scores obtained from the clinical scales showed significant recovery of most of the functions, while the alterations of NCSS and NCS of the median nerve were not significant.ConclusionsWe found a significant reduction in step number and step percentage after follow-up. This alteration was not reflected in standard electrodiagnostic values. The improvement of functional scales alongside the CMAP scan parameters suggests that the CMAP scan could be considered an appropriate outcome measurement in research and clinical fields.