Lack of Influence of Atrioventricular Delay on Stroke Volume at Rest in Patients with Complete Atrioventricular Block and Dual Chamber Pacing

Dual chamber pacing (DDD) maintains atrioventricular (AV) sequence; AV delay programmability modifies the relationship between atrial and ventricular contraction. To evaluate the hemodynamic effects of such a modification, ten patients with a DDD unit for complete AV block were studied by time-motion (M-mode) and Doppler echocardiography during inhibited ventricular pacing (VVI), atrial-triggered ventricular pacing (VDD) and atrioventricular sequential pacing (DVI) at different AV delay (90, 140, 190, 240 msec). A significant improvement in stroke volume (SV) (15%-20%, P less than 0.05) was seen during DDD versus VVI pacing; no changes, however, were observed in the same patient with different AV delay or during DVI versus VDD pacing. These data suggest that programming of AV delay does not affect systolic performance at rest; longer diastolic filling times recorded during DDD pacing with "short" AV delay (90-140 msec) do not seem to be a hemodynamically relevant epi-phenomenon of PM programming.     

S-IgA CHOLERA TOXIN AND ROTAVIRUS ANTIBODY IN HUMAN COLOSTRUM

Abstract. S-IgA antibodies against cholera toxin and rotavirus were assayed in 43 colostral samples by means of an enzyme-linked immunosorbent assay (ELISA). All specimens contained specific S-IgA antibodies against both antigens. Significant antibody titres to the antigens were demonstrated in almost all colostral samples.     

THE EFFECT OF CHLORDIAZEPOXIDE AND PETHIDINE, ALONE AND IN COMBINATION, ON THE RESPIRATORY RESPONSE TO CARBON DIOXIDE

The respiratory effects following the intravenous administrationof chlordiazepoxide (1 mg/kg) and pethidine (0.5 mg/kg), bothalone and as a mixture, were studied by means of carbon dioxidestimulus-response curves. Eight healthy adult volunteers demonstratedno statistically significant respiratory depression after receivingchlordiazepoxide. Pethidine alone caused depression for 2 hours,and in combination with chlordiazepoxide the duration was prolongedto 4 hours (the duration of the study period). ^*Preliminary presentation of these data was made at the 40thAnniversary Congress, Section of Anes-thesiology, Pan-AmericanMedical Association, May 1, 1965, Miami Beach, Florida. Present address: Karolinska Institute, Thoracic Clinic, Stockholm,Sweden.     

Concurrence Between the Maxillary Midline and Bisector to the Interpupillary Line

Purpose:  Symmetry is one of the factors that contributes to facial harmony, and in oral rehabilitation it determines the success of esthetic treatment. Therefore, the aim of the present study was to analyze the axial symmetry between the bipupillar midline and maxillary central incisors midline of 102 dental students (both genders) distributed across five Brazilian dental schools.
Materials and Methods:  Students with no teeth missing and who had never been subjected to any dental treatment were selected. Photographs were taken with a Dental Eye III camera with a 100-mm macro objective and ratio of 1 : 10 from natural size, recorded on an Ektachrome ASA/ISO 100 film. The images were developed and applied to Microsoft Office Power Point 2007 software. The results were analyzed by analysis of variance and Student's t -test (α = 0.05).
Results:  There was no significant correlation between bipupillar midline and the maxillary dental midline, irrespective of gender.
Conclusion:  No significant coincidence was observed between the interpupillary and dental midline. However, the interpupillar distance and its relationship with other anatomic structures may be used as a reference in treatment, but measurements must be assessed individually.  

CLINICAL SIGNIFICANCE

Anatomic measurements and facial proportions can be helpful during the planning of esthetic oral rehabilitation.     

PAPULAR MUCINOSIS (SCLEROMYXOEDEMA) COMPLICATING DIFFUSE SYSTEMIC SCLEROSIS: CLINICAL FEATURES AND ELECTRON MICROSCOPE OBSERVATIONS

Papular mucinosis (scleromyxoedema) is an uncommon disordercharacterized by generalized papular eruption and cuta neousinduration, which may be associated with a variety of extracutaneousmanifestations. Although scleroderma and papular mucinosis sharemany features, they are clinically and histologically distinctentities. We report here a patient with diffuse sclerodermawho developed superimposed papular mucinosis. Degranulatingmast cells were a prominent ultra- structural finding in theinvolved skin. The occurrence of scleroderma and papular mucinosis,two uncommon cutaneous indurative diseases, in the same patienthas not been described previously. KEY WORDS: Papular mucinosis, Scleromyxoedema, Systemic sclerosis, Cutaneous mucinosis     

Survival of Transvenous ICD Leads in Young Patients

Background : In adults, transvenous implantable cardioverter defibrillator (ICD) lead failure rates are significant, and their occurrence increases with time from implant. There are limited data in children. The goal of this study was to assess lead survival in young patients undergoing ICD implantation at a single center. Methods : Records of patients under 21 years old with transvenous ICD leads implanted at our center from June 1997 to August 2007 were retrospectively reviewed. Age, weight, height, diagnosis, lead and generator model, venous access technique, generator position, pacing thresholds, lead impedance, and R wave size were recorded. “Lead failure” was defined as any lead problem requiring surgical intervention to restore proper function to the ICD system. Results : Seventy‐one transvenous leads were included (70 patients). Average age at implant was 14.8 years (range 5.7–19.5). All the devices were implanted by a single operator (HMS). Venous access was obtained via cephalic cutdown in 66/71. Mean follow‐up time was 2.8 years (range 0.2–7.8 years, median 2.3 years). There were no infections requiring explantation. There were four lead failures. Three were lead fractures, occurring 12, 13, and 19 months after implant. The fourth lead failed when an arrhythmia was not appropriately detected, and a second dedicated rate‐sensing lead was thus implanted. Univariate analysis did not identify any variable to be a significant predictor of lead failure. Kaplan–Meier survival analysis demonstrated 5‐year lead survival at 89.6%. Conclusions : ICD lead survival in children, when performed by an experienced operator, is similar to that found in adults. (PACE 2010; 33:186–191)