Outcome of aortic valve repair in children with congenital aortic valve insufficiency.

OBJECTIVE: Surgical aortic valvotomy has a long history of providing excellent palliation for aortic stenosis in infancy and childhood. The fate of aortic valve repairs for dominant aortic regurgitation in this same age group is considerably less clear. METHODS: From 1990 to 2000, a total of 21 patients underwent aortic valve repair for aortic regurgitation at our institution. Seventeen patients were younger than 17 years at the time of repair (3-17 years, mean 8.1 +/- 3.7 years). Of these 17 children, 6 (35%) had bicuspid valves and 11 (65%) had tricuspid valves. Type of repair varied with valve type, but repair generally consisted of commissure resuspension, partial commissure closure, triangular resection of redundant leaflets, or some combination. RESULTS: There were no deaths. Follow-up ranged from 1 to 11 years (mean 5.3 +/- 2.4 years). At present 3 of 17 (17.6%) have mild aortic regurgitation according to echocardiography and 6 (35.2%) have moderate aortic regurgitation. In 8 of 17 cases (47.1%) the repair clearly failed, requiring reoperation from 0.5 to 73 months after the original operation (mean 18.9 months). Reoperation consisted of 6 Ross procedures and 2 mechanical aortic valve replacements. There were no deaths at the secondary operation. CONCLUSION: Aortic valve repair in children with a dominant feature of aortic insufficiency tended to fail progressively and at a high rate. Leaflet thickening was associated with higher risk of repair failure in this series. The threshold for aortic valve replacement should remain low.

Effect of a selection and postoperative care protocol on survival of infants with hypoplastic left heart syndrome.

BACKGROUND: We report the development and implementation of a program designed to assign patients preoperatively to either transplant or Norwood procedure based on a score derived from known risk factors and to enhance postoperative care of infants undergoing the Norwood procedure. METHODS: A weighted score for each of six variables comprised the scoring system: ventricular function, tricuspid regurgitation, ascending aortic diameter, atrial septal defect blood flow characteristics, blood type, and age. The scoring system was used to prospectively assign mortality risk and lead to recommendation of either Norwood procedure or transplantation. RESULTS: Survival following the Norwood procedure significantly improved after the management program was implemented (88% versus 40% at 48 hours, 57% versus 10% at 30 days, and 50% versus 10% at 1 year, p < 0.0001 at each time point). The survival of the group that received a score of 7 or less (high risk) who underwent the Norwood procedure was 78% at 48 hours, 44% at 30 days, and 33% at 1 year; survival rates among patients considered lower risk (greater than 7) were 100% at 48 hours and 80% at 30 days and 1 year. Transplant outcomes remained unchanged. CONCLUSIONS: We report improved survival following the Norwood procedure after the implementation of an institutional management approach aimed at improving the outcome of infants with hypoplastic left heart syndrome and may help neutralize historical biases toward Norwood procedure or transplantation.

Robotically assisted cardiac surgery: minimally invasive techniques to totally endoscopic heart surgery.

Over the past decade, advancements in cardiac surgery occurred secondary to improvements in technology and the desire for a less invasive approach to operations in general. Minimally invasive cardiac surgery has progressed from partial sternotomy incisions to totally endoscopic open-heart procedures with robotic-assistance. There are 2 major companies that produce robotic equipment for use in cardiac surgery. These companies must undergo Food and Drug Association (FDA) mandated clinical trials on each cardiac surgical procedure, before it can be approved for public use. The surgeon must demonstrate clinical proficiency to operate the robotic equipment per FDA approved company testing. The use of computer (robotic) enhancement is well documented for coronary artery bypass grafting and selected cardiac valve procedures. Recent advancements are now being directed at congenital heart disease. The use of robotic-assisted totally endoscopic atrial septal defect closure is a tremendous advancement in congenital cardiac surgery. The future of robotic cardiac surgery will hopefully expand to cover more advanced valve procedures, congenital heart defects, and other procedures once robots are further modified for pediatric use.

Fate of polytetrafluoroethylene monocusp pulmonary valves in an animal model.

Creation of a competent pulmonary monocusp valve facilitates transition from pressure to volume overload following right ventricular outflow tract reconstruction. To determine intermediate-term results and performance of the different types of polytetrafluoroethylene membrane used to construct monocusp valves and transannular patches, 12 infant lambs underwent excision of the native pulmonary valve and insertion of a monocusp valve and transannular patch made from one of 4 types of membrane. Echocardiography was performed after 3, 6, 9, and 12 months, and cardiac catheterization was carried out prior to animal sacrifice at 6 (n = 4) or 12 (n = 8) months. There was no postoperative morbidity or mortality. On echocardiography, 6 valves were mobile (50%), 4 had diminished mobility (33%), and 2 were fixed (17%) prior to sacrifice. At catheterization, mild, moderate, and severe pulmonary regurgitation was observed in 4 valves each (33%), with no stenosis. Right ventricular outflow tract reconstruction with polytetrafluoroethylene monocusp valves can be safely accomplished with good early competence, variable degrees of late insufficiency, and no stenosis. Compared to an open microstructure, the closed polytetrafluoroethylene microstructure showed a milder fibroinflammatory reaction and fewer foci of microcalcification, with sparing of the free edge of the monocusp; this correlated with better intermediate-term hemodynamic performance.

Prospective randomized study of a protein-based tissue adhesive used as a hemostatic and structural adjunct in cardiac and vascular anastomotic repair procedures.

BACKGROUND: The purpose of this study was to determine whether adjunctive use of the bovine serum albumin and glutaraldehyde tissue adhesive BioGlue (BioGlue Surgical Adhesive; CryoLife, Inc) could reduce the rate of anastomotic bleeding in patients undergoing cardiac and vascular repair procedures when compared with a standard repair control. This was a prospective multicenter, randomized, controlled clinical trial conducted in accordance with the IRB at each participating institution. STUDY DESIGN: A total of 151 patients consented to participation and were randomly assigned to standard repair plus BioGlue (n = 76) or standard repair alone (n = 75). These two groups were statistically homogeneous for age, gender, race, procedure, and number of anastomoses. Patients underwent cardiac procedures (n = 49), aortic procedures (n = 105), or peripheral vascular procedures (n = 48). RESULTS: Anastomotic bleeding was significantly reduced in the BioGlue group (18.8% of anastomoses) compared with the control group (42.9% of anastomoses, p < 0.001). Pledget use was reduced in the BioGlue group (26.2%) compared with the control group (35.9%, p = 0.047). Days in the ICU and total days in the hospital were slightly higher in the control group. Adverse event profiles were equivalent between the two groups except for occurrence of neurological defects, which were threefold less in the BioGlue group (p = 0.009). CONCLUSIONS: This study demonstrates that using BioGlue as an adjunct to standard repair methods is safe and significantly reduces the occurrence of intraoperative anastomotic site bleeding in cardiac and vascular repair patients. Using BioGlue along suture lines reinforces anastomoses, thus minimizing pledget use.

Baboons undergoing orthotopic concordant cardiac xenotransplantation surviving more than 300 days: effect of immunosuppressive regimen.

OBJECTIVE: We reviewed long-term survival among hosts in 3 consecutive series of a rhesus monkey-baboon orthotopic cardiac xenotransplantation model with reference to host immune response, including the effectiveness in preventing rejection and limiting toxicity concerning infection, to evaluate specific immunosuppressive regimens for long-term outcomes. METHODS: Six juvenile baboons surviving more than 300 days after transplantation were reviewed. Regimen A consisted of splenectomy, FK506, methotrexate, and antilymphocyte globulin. Regimen B consisted of pretransplantation and chronic maintenance with cyclosporine A (INN: ciclosporin), methotrexate, and antithymocyte globulin. Regimen C was the same as regimen B plus pretransplantation total lymphoid irradiation and intraoperative donor bone marrow cell infusion. Rejections were detected by means of echocardiography. RESULTS: Long-term survivors in 3 groups were followed for a range of 332 to 515 days (mean, 436 days). Rejection frequency in regimens A, B, and C was 0.35, 0.58, and 0.18 per month, and rescue therapy days were 23 (4.8%), 123 (9.5%), and 20 (2.4%), respectively (P <.0001). Infection frequency was 0.58, 0.56, and 0.19 per month, and therapy days were 192 (38.2%), 164 (12.6%), and 7 (0.9%), respectively (P <.0001). Concerning the host immune response, interleukin 2-activated T cells of all groups during rejection-free periods showed lower numbers compared with those of control animals (P <.0005), and regimen C was the lowest among 3 groups (P <.01). The production of xenoantibody was sufficiently attenuated in all groups. CONCLUSION: Regimen C leads to long-term survival with fewer rejection and infection episodes by means of suppression of the interleukin 2 pathway and xenoantibody production.

Duration of graft cold ischemia does not affect outcomes in pediatric heart transplant recipients.

BACKGROUND: Utilizing donor hearts with prolonged graft ischemia may extend the donor pool. METHODS AND RESULTS: The medical records of 363 infants and children, aged 1 day to 17 years, transplanted at Loma Linda University between November 1985 and March 2001, were retrospectively reviewed. Fourteen children received organs with prolonged ischemic times (>8 hours)(PIT) compared with 14 with short ischemic times (< or =90 minutes)(SIT). There were no significant differences when comparing donors for gender, age, weight, cause of death, or duration of cardiopulmonary resuscitation. Preoperative donor shortening fraction (%), as determined by echocardiography, was significantly higher in the SIT group (44.5 versus 36.5%; P=0.006). There were no significant differences between PIT and SIT recipients when comparing age at transplant, weight at transplant, waiting time, weight mismatch, postoperative days on ventilator, duration of inotropic support, and hospital stay. Cardiopulmonary bypass time was significantly longer in the PIT group (140.5 versus 80.5 minute; P=0.001). Median length of follow-up for both groups was approximately 5 years. Five grafts were lost in the PIT group; 7 were lost in the SIT group, with 1 early graft loss in each group. Significant posttransplant coronary artery disease was diagnosed in 2 recipients in each group (PIT: 80 and 42; SIT: 84 and 67 months posttransplant). There was no significant difference between groups in actuarial graft survival. Number of rejection episodes and hospital readmissions during the first posttransplantation year did not differ significantly between groups. CONCLUSION: Late outcomes were not adversely affected by donor hearts preserved by single dose cold crystalloid cardioplegia with greater than 8 hours of cold ischemia.

Total lymphoid irradiation for refractory rejection in pediatric heart transplantation.

BACKGROUND: We evaluated the role of total lymphoid irradiation (TLI) in the management of refractory rejection among pediatric heart transplant patients. METHODS: Eleven of 298 patients underwent TLI at 6 to 195 months of age and were divided into subgroups: those who survived (group A, n = 7) and those who did not survive beyond 1 year after TLI (group D, n = 4). Non-TLI recipient data were considered as the controls. RESULTS: Six out of 11 patients died eventually (54%). TLI was initiated 3 to 107 months after transplantation with a dosage of 600 to 840 cGy. The pre-TLI rejection rate (0.62 +/- 0.40 per month) was higher (p < 0.0001); however, the post-TLI rejection rate (0.24 +/- 0.65 per month) showed no significant difference from the control rejection rate. The Cox proportional hazard model found significance for TLI as a risk factor for development of posttransplant coronary artery disease (relative risk, 4.8; 95% CI, 1.1 to 21.3) and posttransplant lymphoproliferative disease (relative risk, 47.9; 95% CI, 1.6 to 1,475.3), respectively. Although the rejection rate decreased after TLI in both groups (group A pre/post, 0.51 +/- 0.31/0.06 +/- 0.08 per month; group D pre/post, 0.82 +/- 0.49/0.57 +/- 1.09 per month), significance was obtained only in group A (p = 0.018). CONCLUSIONS: TLI was an effective adjunct for reversal of refractory rejection in pediatric heart transplantation by reducing the rejection rate. Great care must be taken for the risk of development of coronary artery disease or lymphoproliferative disease.

Pericardial and synthetic monocusp valves: Indication and results.

Construction of a monocusp valve is a simple, expeditious, and inexpensive method to prevent the known sequelae of pulmonary insufficiency in the immediate post-operative period whenever a transannular patch is used to establish right ventricular-pulmonary artery continuity. A detailed description of monocusp materials, construction and indications as well as late results are included. Copyright 1999 by W.B. Saunders Company