Pulmonary artery sling: current results with cardiopulmonary bypass.
ABSTRACT We have used cardiopulmonary bypass with left pulmonary artery reimplantation for pulmonary artery sling repair since 1985. This review presents our current results with this technique, emphasizing the importance of diagnosis and treatment of frequently associated tracheal stenosis.
Since 1985, 34 patients have undergone pulmonary artery sling repair using a median sternotomy and cardiopulmonary bypass. Age ranged from 9 days to 43 years (mean 2.1 ± 7.5 years, median 0.2 years). Twenty-seven patients (79%) had tracheal stenosis secondary to complete cartilage tracheal rings. All patients had preoperative airway imaging with rigid bronchoscopy, and since 2000 all patients have had computed tomography imaging of the chest with 3-dimensional reconstruction (n = 14). Tracheal repair has included pericardial patch tracheoplasty (n = 7), tracheal autograft (n = 10), tracheal resection (n = 4), and slide tracheoplasty (n = 5). All patients had an echocardiogram, and cardiac lesions repaired simultaneously included atrial septal defect (4), tetralogy of Fallot (2), and ventricular septal defect (1). One patient had a severely hypoplastic right lung, and 3 patients had an absent right lung. In these patients, the left pulmonary artery was translocated anterior to the trachea. In all other patients, the left pulmonary artery was reimplanted into the main pulmonary artery.
There have been no early deaths or complications related to the use of cardiopulmonary bypass. Median hospital stay was 24 days. There have been 4 late deaths. Two late deaths were the result of complications of tracheal surgery (1 pericardial patch [6 months postoperatively] and 1 autograft [1.7 years postoperatively]). One child died of biliary atresia (0.2 years postoperatively), and 1 child died of pneumonia (5.8 years postoperatively). All recent tracheal stenosis repairs have been with slide tracheoplasty. All left pulmonary arteries are patent with a mean percent flow by perfusion scan of 41% ± 13%. Older patients (n = 2) have noted a significant improvement in exercise tolerance.
Pulmonary artery sling is best repaired with median sternotomy, cardiopulmonary bypass, and left pulmonary artery reimplantation. This resulted in uniformly patent left pulmonary arteries in all patients. Preoperative computed tomography imaging, echocardiography, and bronchoscopy are essential for precise operative planning. The frequently associated tracheal stenosis is best repaired with slide tracheoplasty.
- Acta Crystallographica Section A - ACTA CRYSTALLOGR A. 01/1992; 48(3):346-349.
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ABSTRACT: Determining the structure of a crystal by X-ray methods requires repeated computation of the three-dimensional Fourier transform. Over the last few years, algorithms for computing finite Fourier transforms that take advantage of various crystal symmetries have been developed. These algorithms are efficient especially when the sampling space contains a prime number of points in each coordinate direction. In this work, we present a method of combining programs for two relatively prime integers p and q to obtain a program for sampling space containing p · q number of points in each coordinate direction.Advances in Applied Mathematics. 01/1990; 11(3):358-371.