Remote-controlled catheter ablation of accessory pathways: results from the magnetic laboratory.

AIMS: This study evaluates feasibility, safety, and efficacy of magnetic remote-controlled accessory pathway (AP) ablation. METHODS AND RESULTS: The novel magnetic navigation system (MNS) (Niobe, Stereotaxis) creates a steerable magnetic field (0.08 T) controlling the distal magnetic tip of an ablation catheter. In conjunction with a catheter advancer system (Cardiodrive, Stereotaxis) remote catheter ablation is enabled. Conventional electrophysiology study identified AP conduction in 59 patients (37 males, 36+/-14 years, 60 APs). First generation 1-magnet tip (1-M) (group I, n=18), second generation bipolar 3-magnet tip (3-M) (group II, n=27), and third generation quadripolar 3-magnet tip catheters (3-M quad.) (group III, n=14) were used for magnetic remote-controlled ablation. Successful AP ablation was achieved in 67% (group I), 85% (group II), and 92% (group III). A significant decrease of median [IQR: Q1-Q3] fluoroscopy time and dosage was observed: 21.2 [12.1-33.8] min, 1110 [395-3234] microGym2 (group I); 6.5 [4.4-15.4] min, 290 [129-489] microGym2 (group II), and 4.9 [3.4-8.0] min, 129 [74-270] microGym2 (group III). Mean procedure time (217+/-67 min; 182+/-68 min, and 172+/-90 min) significantly decreased in group III. Median number [Q1-Q3] of radiofrequency current applications in groups I, II, and III was 4 [2-9], 4 [2-6], and 2 [2-4], respectively. No complications occurred. CONCLUSION: Remote AP ablation is safe and feasible using the novel MNS. Introduction of the 3-magnet quadripolar ablation catheter significantly improved the efficacy of the procedure.     

Femoral anteversion related to side differences in hip rotation: Passive rotation in 1, 140 children aged 8-9 years

We assessed whether the range of passive hip motion is reliable for predicting abnormal femoral ante-version. We measured the passive medial and lateral rotation in extension in both hips of 1, 140 children between 8 and 9 years of age. The children were divided into 3 groups: group 1: difference between lateral and medial rotation less than 10° group 2: medial rotation more than 10° greater than the lateral; group 3: lateral rotation more than 10° greater than the medial. Group 1 comprised 90% of the children, whereas 8% belonged to group 2 and 2% to group 3.

The angle of femoral neck anteversion was measured in 57 children from the first group, in 67 from the second and in 24 children from the third group, using biplane radiography. The mean anteversion angles in the 3 groups were 24°, 36° and 14°, respectively. To predict an abnormally high anteversion angle (above mean +2SD), the difference between medial and lateral rotation must be 45° or more, whereas an abnormally low anteversion angle (lower than mean -2SD) could be predicted when the lateral rotation was at least 50° higher than the medial rotation.     

Prognostic significance of cytochemical analysis of leukemic M2 blasts

Cytochemical analysis of leukemic blasts from 46 patients with acute myeloblastic M2 leukemia (according to the FAB classification) was performed before and after cytostatic therapy, and compared with findings obtained in 20 age- and sex-matched control subjects. Cytochemical findings for myeloperoxidase (MPO), Sudan black B, acid phosphatase and alpha-naphthyl-acetate esterase (ANAE) were related to the achievement of the first complete remission (CR),i.e. data were compared after the patients had been divided into CR and non-CR groups. The analysis clearly showed that a high proportion of myeloperoxidase- and, to a lesser extent, Sudan black B-positive blasts before treatment may have constituted a significantly unfavourable prognostic factor.     

Pulsed-field gel electrophoretic analysis of leptospiral DNA.

The genomic structures of spirochete species are not well characterized, and genetic studies on these organisms have been hampered by lack of a genetic exchange mechanism in these bacteria. In view of these observations, pulsed-field gel electrophoresis was used to examine the genomes of Leptospira species. Live cells, prepared in agarose plugs, were lysed in situ, and the DNA was analyzed under different electrophoretic conditions. Pulsed-field gel electrophoresis of DNA digested with infrequently cutting restriction enzymes showed that the genome of Leptospira interrogans serovar canicola is approximately 3.1 Mb, while that of the saprophytic L. biflexa serovar patoc I is 3.5 Mb. DNA forms of approximately 2,000 and 350 kb which were present in samples from L. interrogans serovars were not readily detected in nonpathogenic serovars. Three distinct populations, designated type alpha, beta, and gamma, of L. interrogans DNA molecules were further analyzed with two-dimensional gel electrophoresis. Evidence suggested that two of these DNA forms, type alpha and gamma, were linear structures. Pulsed-field gel electrophoresis has proven to be a valuable tool with which to size bacterial genomes and to take the first steps toward characterization of a form of leptospiral DNA which behaves as a linear molecule and which may be related to the virulence of L. interrogans.     

A short-term follow-up comparison of two trans-obturator tape procedures

The objective of the study was to compare the clinical outcomes at the short-term follow-ups of two novel transobturator mid-urethral sling procedures – the transobturator tape (TOT) procedure and the tension-free vaginal tape (TVT)-obturator procedure. The study cohort consisted two groups of 40 women with urodynamically proven stress urinary incontinence (SUI). The patients in one group underwent the TOT procedure, performed according to Delorme (Prog Urol 11:1306–1313, 2001); those in the second group underwent the TVT-obturator operation, performed according to de Leval (Eur Urol 44:724–730, 2003). Intra-operative diagnostic cystoscopy was not performed with either the TVT-obturator or the TOT procedures. The average follow-up was 12 months. The two patient groups were similar in terms of demographic and therapeutic criteria, except for patient age, which was significantly younger in the TVT-obturator group. Previously reported TVT-related operative complications, such as bladder penetration, intra-operative bleeding, field infection and post-operative pelvic floor relaxation, were not observed in patients of either group. Bowel and urethral injuries were also not recorded. The therapeutic failure rates were 10% for the TOT procedure and 5% for the TVT-obturator procedure. Urinary frequency and urgency post-operatively were reported in 25% of the TOT patients and 19% of the TVT-obturator patients, pelvic or vaginal pain affected 10% of the TOT and 5% of the TVT-obturator patients, while post-operative voiding difficulty was experienced by 12.5% of the TOT and 7.5% of the TVT-obturator patients. None of the above-mentioned differences between the two patient groups were of statistical significance. The TVT-obturator and TOT procedures, both minimally invasive, novel, mid-urethral sling procedures, seem to be safe, easy-to-perform and effective in treating female SUI. The patients of both study groups suffered less intra- and post-operative surgical complications than previously been reported in connection with the TVT operation. The TVT-obturator patients had fewer therapeutic failures, less post-operative urinary frequency and urgency, less pelvic pain and less voiding difficulty. All of these findings, however, had no statistical significance; consequently, long-term comparative data collection will be required before solid conclusions can be drawn on the superiority of either of these two operative techniques.     

Co-localization of SCPB-like and FMRFamide-like immunoreactivities in crustacean nervous systems

A monoclonal antibody to the molluscan small cardioactive peptide SCPB and a polyclonal antibody to FMRFamide were used to localize antigens in the stomatogastric nervous system and brain of two species of Cancer. Both antibodies labeled cell bodies, axons, and neuropilar processes in the brain and in the stomatogastric nervous system. All of the SCPB immunoreactive neurons were co-labeled with antibody to FMRFamide. However, antibody to FMRFamide labeled additional neurons of the commissural ganglion and the brain that were not immunoreactive to the monoclonal SCPB antibody.