Renal scar formation in children with recurrent urinary tract infections

Reports of renal scar formation in children even in the absence of vesicoureteral reflux necessitates studying other causes of this major complication. The present study mainly focuses on the role of recurrent urinary tract infections [UTI] in renal scar formation. The records of 53 patients with recurrent UTI and the data on their regular follow up visits were reviewed. Renal scar formation was confirmed by dimercapto-succinic acid [DMSA] scan. DMSA scan, done at a mean age of 8.31 years, revealed renal scar formation in 12 cases [22.44%]. Seventy-five percent of the patients with scar formation and 80.5% without scar were older than 3 years at the time of the first documented UTI. The etiologic organism was found to be Escherichia coli in 89.2% of the infections in the scar forming versus 78.8% in the non-scar forming group. In the presence of normal urinary tract anatomy, recurrent UTI can be a significant cause of renal scar formation in children

Role of tissue-doppler imaging to assess left ventricular function in patients with right ventricular pacing

Right ventricular apical [RVA] pacing has been reported to impair diastolic and systolic function. These changes were usually studied by conventional echocardiography, while tissue-doppler imaging [TDI] has provided a new way to evaluate global and regional systolic left ventricular [LV] function and abnormal LV relaxation. We designed this study to evaluate the changes of TDI-derived indices of asynchrony after RVA pacing. We followed 41 patients with LV ejection fraction [LVEF] >/= 45% and LV end-diastolic dimension [LVEDD] œ 56 mm who underwent single- or dual-chamber RVA pacemaker implantation for performing pacemaker analysis and second 2-dimensional [2D] echocardiography and TDI, at least 4.2 months later. 2D measurements included LVEDD, LV end-systolic dimension [LVESD], left atrial [LA] volume and septum to lateral asynchrony, while TDI measurements were the peak velocities of myocardial shortening [Sm] and early myocardial relaxation [Em]. Considering the exclusion criteria, 20 patients entered the study with the mean age of 66.05 years and follow-up of 7.86 months [4.20-12.25]. The reduction of Sm, Em and LVEF, and the increment of LVEDD, LVESD, septum to lat asynchrony and LA volume were statistically significant. Changes of all these parameters, however, were independent of pacing duration, frequency or mode [single- or dual- chamber]. RVA pacing has deleterious effects on both LV systolic and diastolic parameters of not only conventional echocardiography but also TDI even in patients with normal LV function. Furthermore, LA volume increases significantly

influence of right ventricular apical pacing on left atrial volume in patients with normal left ventricular function

Right ventricular apical [RVA] pacing has been reported to induce several deleterious effects particularly in the presence of structural heart disease but can also involve patients with normal left ventricular [LV] function. Left atrial [LA] enlargement is one of these effects, but the majority of studies have measured LA dimension rather than volume. The present prospective study was designed to assess the effect of RVA pacing on LA volume in patients with normal LV function. The study comprised 41 consecutive patients with LV ejection fraction >= 45% and LV end diastolic dimension <= 56 mm who underwent single-or dual- chamber pacemaker implantation in RVA and followed for LA volume measurement and pacemaker analysis at least during the ensuing 4.2 months. In all, 21 patients were excluded from the study due to five spontaneous wide QRS complex [>=120msec], one recent acute coronary syndrome,one significant valvular heart disease, three pacing frequency <90%, eight death or losing follow up in three cases. In remaining 20 patients, LA volume ragned from 21 to 54 mm3 with mean of 37.3 +/- 9.7 mm3 prior to pacemaker implantation that increased to 31 to 103 mm3 [54.3 +/- 17.0] during follow-up [P<0.001]. RVA pacing might lead to an increase in LA volume even in patients with normal LV function