Right ventricular apical and septal pacing: long term impacts on ventricular function

Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): The costs of the study were afforded by the researchers. Background In patients requiring permanent pacemaker, in order to protect left and right ventricular functions the optimal pacing site has yet to be determined. Conflicting results exist about septal and apical pacing sites. Aim Our purpose was to evaluate the long term effects of right ventricular apical and septal pacing on left and right ventricular functions. Methods We scanned 378 patients from 2007 to 2012 who received a permanent pacemaker for the treatment of symptomatic bradyarrythmia. As exclusion criteria we identified the patients who did not have an echocardiography before the procedure, those who had co-morbidities which cause reduction in ventricular functions, ejection fraction <%45, patients who died and those who rejected our invitation. 54 women and 66 men were eligible for our study. To determine the patients’ New York Heart Association Class (NYHA) we questioned and did the physical examination. Lead position confirmed by fluoroscopy in two planes, and electrocardiograms were obtained. Finally, we compared the pre-procedural echocardiographic data with our up-to-date findings. Results In sixteen patients the lead placement was inferoseptal and in one hundred and four patients apical site. Median follow up was 9 years. The mean ejection fraction before the implantation was 58,86 ± 4,08 in the apical, and 56,37 ± 8,8 in the septal group (p < 0,05). The long term follow up showed that these values have been reduced, 56,66 ± 8,38 for the apical group and 51,33 ± 13,94 for the septal group, respectively (p < 0,05). Placing the right ventricular lead in both septal and apical site resulted in reduced tricuspid annular plane systolic excursion (from mean 2,25 to 2,18, (p < 0,05)), and in increased systolic pulmonary artery pressure (from 35,46 ± 9,93 to 39,84 ± 11,21 (p < 0,05)). There were no differences regarding the mitral and tricuspid insufficiencies, and diastolic functions before the implantation and long term follow up. These findings were independent of neither the etiology of implanting the pacemaker nor the underlying diseases. Conclusion These two selective ventricular pacing sites caused a reduction in both left and right ventricular functions. Despite the ejection fraction declines, most of these patients have a good quality of life, without symptoms and signs of heart failure. But certainly, there is emerging need for more randomized trials in order to describe the optimal RV pacing site. The main purpose must be preserving better ventricular functions in patients requiring permanent ventricular pacing.

The Groote Schuur hospital classification of the orbital complications of sinusitis

The complications of sinusitis have been well described. The most common classifications used for orbital complications have been that of Chandler et al. (1970) and Moloney et al. (1987). With the ready availability of high-resolution computed tomography (CT) scanners, limitations of these classifications have become apparent. The aims of this study were to determine the relative frequency of the various complications associated with acute sinusitis, to determine which groups of sinuses were most frequently involved and to correlate the orbital signs with a new proposed classification of orbital complications. Over a five-year period, 87 consecutive patients were admitted with acute sinusitis. Sixty-three patients (72.4 per cent) had one or more complications. When orbital complications were classified under the proposed classification, all patients with proptosis and/or decreased eye movement had post-septal infection. Visual impairment occurred only in the post-septal group. Most complications had a combination of sinus involvement with the maxillary/ethmoid/frontal combination being the most common. The authors propose a modification of Moloney's classification for orbital complications of acute sinusitis that allows a clear differentiation between pre- and post-septal infection and a radiological differentiation to be made between cellulitis/phlegmon and abscess formation. The latter is of importance when a decision is made on whether surgical intervention is appropriate or not.

Spontaneous Activity in Septal and Hippocampal-Lesioned Rats

30 rats were assigned in equal numbers to control, hippocampal, and septal groups. Ss were observed in a novel situation for three 15-min. sessions with 24 hr. between sessions and measures taken of their sniffing, walking, and grooming rates. The most important difference occurred in the third session when it was found that the type of lesion exerted control over the habituation of different responses. In walking, there was a tendency for Ss in the hippocampal and control groups to decrease their rate over time, while septal-lesioned Ss tended to increase their rate. Both septal and control groups decreased their sniffing rate, whereas the hippocampal group did not. In grooming, neither the hippocampal nor the septal group showed an increase in rate, whereas the control Ss did. The results of the septal-lesioned Ss were regarded as consistent with a conventional response-inhibition hypothesis while the data of the hippocampal group suggested a deficit in attentional mechanisms.