Biomedical subjects

S Y DeLeon

Publications and source records attributed to S Y DeLeon.

At least 37 records · Page 2Linked to original sources

PubMed1993

Surgical techniques in partial anomalous pulmonary veins to the superior vena cava.

Over a 12-year period, 40 patients underwent repair of partial anomalous pulmonary veins (PAPV) draining to the superior vena cava (SVC) proximal to the sinus node. Mean age was 6 +/- 2 years. In all patients, the SVC was cannulated superior to the PAPV, which were baffled with pericardium to left atrium. Six patients had associated defects repaired. In 18 patients (group I), an incision was made at the crest of the right atrial appendage (RAA) and extended upward through the sinus node and to the SVC. After rerouting of the PAPV, the SVC was enlarged using the RAA (atriocavoplasty). In 17 patients (group II), rerouting of the PAPV was accomplished through a right atriotomy. Superior vena caval enlargement was not done. Drainage of the PAPV was close to the right atrium in 14 patients (low) and to the azygos vein (high) in 3. In 5 patients (group III), an incision was made on the SVC and RAA sparing the sinus node. After rerouting of the PAPV, the RAA was anastomosed to the SVC (end to side), providing another outlet for SVC flow. There was no early or late death. Two patients (10%) in group I had late sinus bradycardia. Obstruction of the SVC and PAPV developed in 1 patient in group II with high drainage. Intermittent complete heart block developed in 1 patient in group III who also had ventricular septal defect repair. We conclude that atriocavoplasty is effective for rerouting of the PAPV and enlarging the SVC, but may predispose to sinus node disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1993

Right ventricle-to-aorta conduit in pulmonary atresia with intact ventricular septum and coronary sinusoids.

A 20-month-old girl with pulmonary atresia, intact ventricular septum, and ventriculocoronary connections underwent successful interposition of a right ventricle-to-aorta conduit and Fontan operation. The patient initially had a modified Blalock-Taussig shunt at birth and subsequently a bidirectional Glenn shunt at 8 months of age. After Fontan and right ventricle-to-aorta conduit placement, the suprasystemic right ventricular pressure dropped to systemic levels without causing myocardial injury. Additionally, the right ventricular cavity enlarged. We believe that the use of a right ventricle-to-aorta conduit should provide a valuable alternative and improve the outlook of certain patients with pulmonary atresia, intact ventricular septum, and ventriculocoronary connections.

Cardiac Surgical Procedures↗

PubMed1993

Obligatory Glenn shunt in fenestrated Fontan.

Five high-risk patients undergoing the Fontan operation required large fenestration (1 cm) because of high central venous pressure and low cardiac output. Because of major arterial desaturation, obligatory Glenn shunts were performed. Three patients had pulmonary atresia, 1 had tricuspid atresia 1-B, and the fifth had single ventricle with subaortic stenosis. The age ranged from 16 to 40 months (mean age, 25 +/- 9 months) and weight from 7.9 to 14.6 kg (mean weight, 11 +/- 2 kg). One patient had single and 3 had bilateral subclavian pulmonary artery shunts. The fifth patient had pulmonary artery banding and coarctation repair followed by an aortopulmonary window and central shunt. The first 2 patients repeatedly had to go back on cardiopulmonary bypass for a larger fenestration and subsequently had an obligatory Glenn shunt because of arterial desaturation. The last 3 patients had planned obligatory Glenn shunt and large fenestration. The first patient died on the second postoperative day of a combination of prolonged operation, repeated cardiopulmonary bypass, and periods of hemodynamic instability. Three patients had closure of the adjustable fenestration under local anesthesia at 4, 5, and 8 weeks postoperatively. The last patient is awaiting closure. We believe that in certain high-risk patients, a large fenestration combined with an obligatory Glenn shunt should be considered to minimize repeated cardiopulmonary bypass and urgent tightening or closure of fenestration in the immediate postoperative period.

Arteriovenous Shunt, Surgical↗

PubMed1992

Partial median sternotomy for repair of heart defects: a cosmetic approach.

A modified median sternotomy incision that results in a cosmetically appealing scar is described. It includes the use of a low-lying short skin incision and partial transection of the sternum. The outcome in 182 infants and children indicates that this approach is safe, provides adequate exposure, and has excellent cosmetic results.

Adolescent↗

PubMed1992

Technical modifications for improved results in total anomalous pulmonary venous drainage.

To delineate factors that contribute to improved surgical outcome in patients with total anomalous pulmonary venous drainage, we reviewed the records of 52 consecutive patients. Venous drainage was supracardiac in 25 (48%), cardiac in 12 (23%), infracardiac in 10 (19%), and mixed in five (10%). Preoperative pulmonary venous obstruction was present in 18 patients (35%). Median age at the time of repair was 35 days and weight, 3.7 kg. Repair was performed with deep hypothermia, low-flow cardiopulmonary bypass, and occasional short periods of circulatory arrest. In patients with coronary sinus drainage, the veins were tunneled to the left atrium through an enlarged atrial septal defect, with a mortality of 8% (1/12) and no postoperative stenosis. The approach in patients with supracardiac, infracardiac, and mixed drainage varied with time. In 16 patients, the condition was managed by apical or right-sided exposure of the common vein, anastomosis of the common vein to the left atrium with continuous sutures, and primary closure of the atrial septal defect (type I repair). In the other 24 patients the common vein was approached from the right side through the right atrium and the interatrial septum. Common vein-left atrium anastomosis was performed with interrupted sutures and a piece of pericardium used to augment the anastomosis, prevent common vein distortion, and close the atrial septal defect (type II repair). Mortality in type I repair was 25% (4/16) and in type II repair, 4% (1/24). Follow-up was 7.86 +/- 4.0 years with no late deaths. Postoperative stenosis occurred in five of 14 (36%) patients who had type I repair versus two of 23 (9%) who had type II repair. Multivariate analysis showed that type I repair was a positive risk factor for hospital mortality (p = 0.05) and restenosis (p = 0.04). The technique of transatrial exposure of the common venous chamber, interrupted suturing of the common vein to the left atrium, and pericardial patch augmentation significantly improves survival and decreases risk of restenosis.

Anastomosis, Surgical↗

PubMed1991

Perioperative spinal canal narrowing in patients with Down's syndrome.

Two patients with Down's syndrome undergoing intracardiac operations had segmental and generalized myoclonic movements postoperatively and eventual brain death. Electroencephalography in 1 patient showed no seizure despite the presence of the myoclonic movements. Computed tomographic scan showed possible cerebellar hemorrhage. Ultrasound showed cerebral edema when the pupils became fixed and dilated. Because known postoperative neurologic complications could not fully explain the clinical course, and the myoclonic movements suggested spinal origin, we considered the possibility of atlantoaxial instability causing spinal cord damage related to perioperative head and neck positioning. Postmortem study on the second patient revealed 50% reduction of the spinal canal with hyperextension and 90-degree external rotation of the head and neck. In contrast, similar maneuvers in 3 infants without Down's syndrome resulted in only mild spinal canal narrowing. Although the myoclonic movements could be explained by spinal cord compression at the atlantoaxial level, the explanation for the eventual brain death is unclear. However, kinking of the vertebral arteries related to the positioning could have caused cerebellar ischemia, hemorrhage, and increased intracranial pressure. We believe that attention to the problem might bring further answers in the future.

Down Syndrome↗

PubMed1991

Resternotomy in patients with valved conduits adherent to the sternum.

Twenty-two patients with valved conduits adherent to the sternum underwent resternotomy. Mean age was 10 +/- 6 years, and mean conduit age was 4 +/- 4 years. Diagnoses were D-transposition (7), truncus arteriosus (7), univentricular heart (6), Taussig-Bing anomaly (1), and corrected transposition (1). The majority of patients (68%) had reoperation for outgrown or degenerated conduits. In 17 patients, the sternum was opened with a chisel. Two of these patients sustained conduit neointimal collapse from manipulation, and 3 had conduit tear requiring immediate cardiopulmonary bypass through the femoral vessels. In the last 5 patients, the sternum was opened above and below the conduit, and the inner table was chiseled and left attached to the conduit avoiding injury and undue conduit manipulation. Cardiopulmonary bypass and operation were carried out uneventfully. We believe that the recent technique described provides a safe alternative approach to valved conduits adherent to the sternum.

Adolescent↗

PubMed1991

Extended aortic valvuloplasty: a new approach for the management of congenital valvar aortic stenosis.

A new technique for the treatment of congenital valvar aortic stenosis is described. It consists of augmenting the aortic cusp by extending the commissurotomy incision into the aortic wall around the leaflet insertion, mobilizing the valve cusp attachment at the commissures, and freeing the aortic insertion of the rudimentary commissure. The results of standard valvotomy performed on 48 patients (group 1) were compared with those of the new extended valvuloplasty carried out on 16 patients (group 2). The two groups were comparable in age at operation (2.7 +/- 2.1 years for group 1 versus 2.1 +/- 1.7 years for group 2; p = not significant) and in preoperative pressure gradient (58 +/- 25 mm Hg for group 1 versus 61 +/- 36 mm Hg for group 2; p = not significant). There was no operative mortality in either group. Follow-up is available on all patients, with a mean of 4.3 +/- 2.6 years for group 1 versus 1.7 +/- 0.5 years for group 2 (p = 0.05). There was one late death in group 1. Postoperative gradient was 47 +/- 13 mm Hg in group 1 versus 19 +/- 13 mm Hg in group 2 (p = 0.05). Moderate or severe regurgitation was present in 18 patients (38%) in group 1 and 2 patients (13%) in group 2 (p = not significant). Reoperation was needed in 8 patients (17%) in group 1 versus 2 patients (13%) in group 2 (p = not significant). The described valvuloplasty procedure addresses the unique pathological features of valvar aortic stenosis and provides better relief of the obstruction than the presently available techniques. Longer follow-up is needed to determine the late results of this approach.

Aortic Valve↗

PubMed1991

The Damus-Stansel-Kaye procedure: anatomical determinants and modifications.

Seven of 119 patients undergoing anatomical correction for transposition of the great arteries and Taussig-Bing anomalies without pulmonary stenosis had the Damus-Stansel-Kaye procedure and the rest, the arterial switch. The age of the patients having the Damus-Stansel-Kaye procedure ranged from 0.5 year to 5 years (mean age, 2.2 +/- 1 years). Four patients had transposition, 2 had Taussig-Bing anomaly, and 1 had corrected transposition. Indications for the Damus-Stansel-Kaye procedure were side-by-side great arteries associated with difficult coronary anatomy (5 patients), single coronary system (1 patient), and subaortic stenosis (1). A graft between the ascending and descending aorta for interrupted aortic arch made mobilization and posterior displacement of the ascending aorta for the arterial switch difficult. Subaortic stenosis (1 patient), subpulmonary ventricular septal defect (2 patients), and restrictive ventricular septal defect (4) precluded the Rastelli procedure. In 6 patients, the main pulmonary artery was transected at the band, a proximal main pulmonary artery to aorta anastomosis was complemented with a synthetic patch, and a right ventricle to distal main pulmonary artery valved conduit was inserted. Four patients had closure of the aortic outflow. Two patients had postoperative bleeding and 2, heart block. The only patient who did not have transection of the main pulmonary artery, an omission that led to an obstructed conduit at the distal anastomosis, died late. Two patients subsequently needed aortic outflow closure for critical aortic insufficiency. The Damus-Stansel-Kaye procedure has a definite role and can be safely performed in patients with transposition of the great arteries and Taussig-Bing anomalies.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗

PubMed1991

Advantages of early relief of subaortic stenosis in single ventricle equivalents.

Thirteen patients with single ventricle equivalents and subaortic stenosis underwent relief of the stenosis and subsequent Fontan operation. Nine patients, group 1, had the obstruction relieved at 3.6 +/- 1.6 years of age whenever the pressure gradient became apparent. Four patients, group 2, had the subaortic stenosis operated on at the neonatal period, 10.5 +/- 10 days old, before hemodynamic evidence of obstruction. Preoperative pressure gradient across the outflow tract was 44.2 +/- 4.7 mm Hg in group 1 versus 4.7 +/- 5 mm Hg in group 2 (p = 0.002). Ventricular muscle mass was 186% +/- 18% in group 1 versus 114% +/- 5% of normal in group 2 (p = 0.0001), and mass/volume ratio was 1.12 +/- 0.62 in group 1 versus 0.62 +/- 0.16 in group 2 (p = 0.003). Relief of subaortic stenosis was achieved by proximal pulmonary artery to ascending aorta or aortic arch anastomosis and by systemic to distal pulmonary artery shunt. There was no hospital mortality or complication related to the procedure. At evaluation before Fontan operation, 4.3 +/- 1.6 years after relief of subaortic stenosis in group 1 and 3.2 +/- 0.9 years in group 2, the pressure gradient across the ventricular outflow tract was 4 +/- 3 mm Hg in group 1 versus 3 +/- 2 mm Hg in group 2 (p = not significant), ventricular muscle mass was 184% +/- 31% in group 1 versus 114% +/- 5% of normal in group 2 (p = 0.003), and the mass/volume ratio was 1.17 +/- 0.2 in group 1 versus 0.62 +/- 0.2 in group 2 (p = 0.003).(ABSTRACT TRUNCATED AT 250 WORDS)

Aorta↗

PubMed1991

Surgical options in subaortic stenosis associated with endocardial cushion defects.

Over a 15-year period, 12 patients with endocardial cushion defects undergoing correction had subaortic stenosis requiring operative intervention. Ages ranged from 4 months to 17 years (mean, 7 +/- 6 years) and subaortic gradients from 15 to 100 mm Hg (mean, 60 +/- 25 mm Hg). Subaortic stenosis was due to discrete fibromuscular tissues in 7 patients, mitral valve malattachment in 3, and tunnel outflow in 2. In 2, the subaortic stenosis was clinically significant at the time of endocardial cushion defects repair, whereas in 10 it was noted 2 to 14 years postoperatively (mean, 6.3 +/- 5 years). Surgical relief of subaortic stenosis was accomplished by resection of muscle tissues in 7, apicoaortic conduit insertion in 2, modified Konno procedure (aortic valve preserved) in 2, and lifting of malattached mitral valve from the outflow in 1. There was no early death and one late death (infected conduit). Severe mitral insufficiency developed in the patient who had the mitral valve lifted and necessitated valve replacement. Postoperative echocardiographic gradient in 9 patients ranged from 0 to 36 mm Hg (mean, 10.5 +/- 14 mm Hg). Clinically significant subaortic stenosis has not developed in any patient in 15 years of follow-up (mean, 5 +/- 4 years). We conclude that in subaortic stenosis associated with endocardial cushion defects, resection is effective for discrete obstruction, whereas a modified Konno procedure is preferable for obstruction due to tunnel outflow or mitral valve malattachment.

Aortic Valve Stenosis↗

PubMed1991

Surgical management of the conal (supracristal) ventricular septal defect.

Surgical management of the conal (supracristal) ventricular septal defect differs significantly from the management of the perimembranous (infracristal) ventricular septal defect. The absence of a portion of the conal septum can lead to prolapse of the right cusp of the aortic valve, which predisposes these patients to aortic insufficiency. Between January 1980 and December 1989, 36 children with conal ventricular septal defect underwent intracardiac repair. Diagnosis was by echocardiography, cardiac catheterization, and intraoperative exploration. Preoperative evaluation showed that 26 patients (72%) had aortic valve prolapse and 16 (44%) had aortic insufficiency. Pulmonary-to-systemic flow ratios ranged from 1:1 to 3.5:1 (mean 2.0:1.0). Ten patients (27%) were believed to have clinical congestive heart failure. Age at the time of operation ranged from 2 weeks to 18 years (mean 5.5 years). Operative exposure was through the pulmonary artery (26), aorta (4), right ventricle (3), or right atrium (3). Simultaneous aortic valve suspension for aortic insufficiency was performed in four patients. Operative survival was 100%. Follow-up is complete in all patients and ranges from 0.5 to 9 years (mean 4.3 years). All patients are in normal sinus rhythm. No residual ventricular septal defects have been identified. Twenty-three of 36 patients (64%) have no evidence of aortic insufficiency; 12 of 36 (33%) have trivial or mild aortic insufficiency. One patient with initial severe aortic insufficiency underwent repeat aortic valvuloplasty 3 years after ventricular septal defect closure and aortic valve suspension. No patients have required aortic valve replacement. Surgical management of the conal ventricular septal defect differs from that of the perimembranous ventricular septal defect in two critical aspects. The operative approach should be through the pulmonary artery. This allows the best exposure of the remaining conal septum and the pulmonary and aortic valve leaflets, facilitating closure of the defect without injury to the valves or conduction system. Conal ventricular septal defects should undergo early closure, regardless of shunt volume, to prevent progressive aortic insufficiency.

Adolescent↗

PubMed1991

Conal enlargement for diffuse subaortic stenosis.

Twelve patients underwent conal enlargement for diffuse subaortic stenosis over a 3 1/2-year period. The subaortic stenosis was due to tunnel outflow in 11 and malattached mitral valve in one. Mean age was 4.4 +/- 4 years and mean subaortic gradient was 50 +/- 21 mm Hg. Three infants had a malalignment ventricular septal defect. In eight patients significant obstruction occurred 2 to 7 years (mean 4 +/- 2) after simple resection of subaortic stenosis (n = 2), ventricular septal defect closure (n = 2), ventricular septal defect closure and subaortic stenosis resection (n = 2), and canal repair (n = 2). In three infants the tunnel outflow distal to a malalignment ventricular septal defect was enlarged and closed with the defect. In three patients with subaortic stenosis proximal to a previously repaired ventricular septal defect, transatrial conal enlargement through the ventricular septal defect was performed. Another patient without a ventricular septal defect had transatrial conal enlargement. The remaining five patients had the modified Konno procedure. Two patients had postoperative complete heart block and one infant had insertion of an apicoaortic conduit for aortic anulus hypoplasia 9 months later. One patient died of pneumonia during the follow-up period. Postoperative echographic outflow gradients up to 3 1/2 years (mean 1.2 +/- 1) ranged up to 25 mm Hg (mean 7 +/- 11) and were mainly at the aortic level. The 11 surviving patients are doing well up to 3 1/2 years of follow-up (mean 1.5 +/- 1). We conclude that conal enlargement procedures with aortic valve preservation are preferable, effective, and can be safely performed for diffuse subaortic stenosis in infants and children.

Aortic Valve↗

PubMed1990

Transatrial relief of diffuse subaortic stenosis after ventricular septal defect closure.

Transatrial enlargement of the left ventricular outflow tract for serious obstruction was performed in 3 patients with previous ventricular septal defect closure. Two patients had recurrent subaortic stenosis as resection had already been performed at initial operation. In all patients, the obstruction was located below the ventricular septal defect patch. Patch enlargement of the left ventricular outflow tract was carried out by opening the ventricular septal defect patch through the tricuspid valve and extending the incision downward through the area of obstruction and the left ventricular body. All patients had uneventful postoperative course and effective relief of left ventricular outflow tract obstruction. We feel that the approach is simple and effective; it avoids a right ventriculotomy and provides a viable option in certain patients with left ventricular outflow tract obstruction.

Aorta↗

PubMed1990

Exit block in pediatric cardiac pacing. Comparison of the suture-type and fishhook epicardial electrodes.

Ninety-seven consecutive permanent epicardial pacemaker implantations were performed with either suture-type (group I, n = 52) or fishhook electrodes (group II, n = 45). In addition to epicardial fixation of the electrodes at the collar area, the suture-type was further secured in place by tying the electrode's suture at its exit to another nonabsorbable pledget-supported suture. Acute thresholds and slew rates were not significantly different between the two groups. Although the R wave was lower in group I (8.4 +/- 3.5 mV) than in group II (11.8 +/- 6, p less than 0.01), no sensing problems occurred. The larger surface area of suture-type electrode led to lower resistance in group I (271 +/- 61 omega) compared with group II (356 +/- 72, p less than 0.001); however, the difference in pacemaker generator longevity did not appear significant (group I, n = 12, mean 4.7 +/- 1.6 years; group II, n = 4, mean 5 +/- 0.6 years). The incidence of exit block was significantly higher in group II (40%, 18/45) than in group I (8%, 4/52, p less than 0.01). The length of the stimulation tip and better fixation of the suture-type electrode probably accounted for the observed difference in the incidence of exit block between the two electrodes.

Adolescent↗

PubMed1990

An alternative approach to the surgical management of physiologically corrected transposition with ventricular septal defect and pulmonary stenosis or atresia.

A modified approach to the surgical management of corrected transposition of the great vessels with ventricular septal defect and pulmonary stenosis or atresia was used successfully in two patients. The procedure consisted of performing a venous switch operation, directing the blood flow from the morphologically left ventricle (right-sided chamber) into the aorta through the ventricular septal defect and inserting a valved conduit between the left-sided morphologically right ventricle and the pulmonary artery. This approach has several advantages when compared with the traditional surgical management, which consists of closure of the ventricular septal defect and a left ventricular (right-sided chamber) to pulmonary artery conduit. It uses the morphologically left ventricle as the systemic pumping chamber, thereby minimizing long-term ventricular failure. It allows closure of the defect from the right ventricular side of the septum, thus decreasing the prevalence of complete atrioventricular block. It also avoids use of the tricuspid valve as the systemic atrioventricular valve and therefore decreases the chance of postoperative valve regurgitation.

Adult↗

PubMed1989

Direct tricuspid closure versus atrial partitioning in Fontan operation for complex lesions.

Thirty-three patients with complex lesions undergoing the Fontan operation needed either direct tricuspid closure (group 1, 14 patients) or atrial partitioning (group 2, 19 patients). In group 1, the tricuspid patch was sutured to the annulus leaving the coronary sinus draining to the systemic venous atrium. In group 2, atrial partitioning was accomplished with either a Dacron or a polytetrafluoroethylene patch, leaving the coronary sinus draining to the pulmonary venous atrium. Intraoperative distention of the left side was used to check for residual defects. In group 1, complete heart block developed in 5 patients (36%) and patch disruption, in 4 patients (29%). There were 3 late deaths (21%), which were due to sudden death, sepsis caused by Candida, and liver failure. In group 2, no patient had heart block, and patch disruption developed in 1 patient (5%). There was 1 early death (5%) and 2 late deaths (11%), which were due to sepsis caused by Candida and renal failure. Our experience suggests that atrial partitioning is a better approach than direct tricuspid patch closure in patients with complex lesions undergoing the Fontan operation.

Adolescent↗

PubMed1989

Transposition of the great arteries: a comparison of results of the mustard procedure versus the arterial switch.

Sixty infants with transposition of the great arteries and intact ventricular septum underwent primary surgical correction in the first 3 months of life. Twenty-three patients had a Mustard procedure (group 1) and 37 patients, an arterial switch operation (group 2). The mean age at the time of repair was 42 +/- 31 days for group 1 and 8 +/- 6 days for group 2 (p less than 0.001). The mean weight at the time of repair was 3.6 +/- 0.7 kg for group 1 and 3.4 +/- 0.5 kg for group 2 (p = not significant). Operative mortality was 8.7% (2/23) in group 1 and 8.1% (3/37) in group 2 (p = not significant). The incidence of arrhythmias in the early postoperative period was 39% (9/23) in group 1 and 11% (4/37) in group 2 (p less than 0.01). All patients were followed a mean of 4.8 +/- 2.4 years in group 1 and 2.6 +/- 1.4 years in group 2 (p less than 0.001). Postoperative catheterization has been performed in 86% (18/21) of group 1 operative survivors and 50% (17/34) of group 2 operative survivors. Ejection fraction of the systemic ventricle was 79% +/- 15% of predicted normal in group 1 and 98% +/- 6% in group 2 (p less than 0.005). The incidence of late arrhythmias was 57% (12/21) in group 1 and 3% (1/34) in group 2 (p less than 0.001). There have been 2 late deaths in group 1 and 1 late death in group 2 (p = not significant).(ABSTRACT TRUNCATED AT 250 WORDS)

Arrhythmias, Cardiac↗