Preservation of All Chordae Tendineae and Papillary Muscle During Mitral Valve Replacement with a Tilting Disc Valve

Mitral valve replacement was performed in 21 patients using a surgical technique that preserves the entire papillary muscle and chordal apparatus. With this technique, the anterior mitral leaflet is split from the center of the free edge toward the annulus. Bilateral incisions are made from the proximal end of this split to the two mitral commissures, detaching the anterior leaflet from the annulus. These two halves of the leaflet, with all chordae intact (corresponding to the anterolateral and posteromedial papillary muscles), are judiciously trimmed to remove areas of leaflet untethered by chordae tendineae and (when necessary) fibrous thickening; then swung posteriorly and sutured to the posterior mitral annulus using mattress sutures with pledgets. This surgical technique is expected to favor the preservation of left ventricular function and avoid occurrence of irreversible left ventricular dilation/dysfunction, and has been used successfully for calcific and degenerative etiologies, using both tilting disc valves and porcine bioprostheses. It is especially useful in the implantation of tilting disc and bileaflet mechanical prostheses because anterior subvalvular chordae tissue may interfere with the disc excursion and relocated to the posterior leaflet annulus.     

Exclusion from proximal 11q of a common gene with megaphenic effect on atopy

We have typed three markers on proximal 11q in 131 random families with three or more children studied for atopy. A summary map that includes the FCER1B candidate was constructed. Using a 2-locus disease model, we performed combined segregation and linkage analysis of three models, none of which suggested linkage. Nine marker loci on other chromosomes were also negative. In the regions swept by these 12 markers we cannot rule out a rare gene, perhaps of large effect, nor a common gene of small effect. However, a common gene of large effect is excluded. These results and alternative strategies are discussed in the perspective of inconsistent evidence for a major atopy gene.     

Outcome analysis of the transglabellar/subcranial approach for lesions of the anterior cranial fossa: A comparison with the classic craniotomy approach

The classic approach to anterior skull base lesions uses bifrontal craniotomies together with lateral rhinotomies. This approach requires frontal lobe retraction and is associated with postoperative anosmia and the development of frontal lobe encephalomalacia. The transglabellar/subcranial approach permits removal of anterior skull base lesions without frontal lobe retraction and avoids facial scars. No studies to date, however, have directly compared the two approaches in terms of patient morbidity. The present retrospective study compares the two approaches when used for the removal of anterior skull base lesions in terms of estimated blood loss, number of transfusions, number of days in the hospital and intensive care unit, and postoperative complications. Twenty patients with anterior skull base lesions were examined. The classic approach was used on 10, and the transglabellar/subcranial route was used on 10. When compared with the classic approach, the transglabellar/subcranial approach resulted in a lower estimated blood loss and subsequent transfusion rate, fewer days in the hospital and intensive care unit, and lower numbers and less severe types of complications. Furthermore, visualization of the tumors before resection with the transglabellar/subcranial approach allowed preservation of olfaction in virtually all of these patients. Although this study represents a small sample population, the results are sufficiently impressive to favor the transglabellar/subcranial approach for the removal of a variety of anterior skull base lesions. (Otolaryngol Head Neck Surg 1997;116:642-6.)     

Automatic jet ventilation in children anaesthetized by the T-piece circuit

Investigation was carried out in ten children aged between one month and six years, who were anaesthetized by the T-piece circuit. The volume of the reservoir tubing of the T-piece was 250 ml. Ventilation was controlled automatically by oxygen jets which were delivered via an injector attached to the reservoir tubing. The oxygen jets were regulated by an electronically-controlled solenoid valve. The children were ventilated by a tidal volume about 12 ml±kg^?1 at a rate of 12-20 per min depending on their age, while the FGF varied between 3 and 6 l min^?1 depending on their body weight. The resulting FIO₂ ranged between 0.32 and 0.34 which was expected from the oxygen:nitrous oxide mixture (1:2), denoting no mixing of the oxygen jets with the anaesthetic mixture. The PA_co2 was ventilation-dependent, and ranged between 4±6-5±3 kPa (35-41 mmHg). The results suggest that automatic jet ventilation facilitates controlled ventilation in children anaesthetized by the T-piece circuit, while maintaining the original simplicity of the T-piece.;