Biomedical subjects

Tara Karamlou

Publications and source records attributed to Tara Karamlou.

At least 19 recordsLinked to original sources

PubMed2007

Surgical outcomes in the treatment of patients with tetralogy of Fallot and absent pulmonary valve.

OBJECTIVE: Tetralogy of Fallot and absent pulmonary valve (TOF/APV) is associated with significant pulmonary artery dilatation and airway compression. Treatment of infants presenting with respiratory symptoms early in life is associated with high mortality (20-60%). We aim to report our results and identify factors associated with survival and prolonged ventilation. METHODS: We performed a retrospective review of 62 consecutive patients following repair of TOF/APV (1982-2006). Median age at repair was 1.4 years (1 day-35 years). Twenty patients required preoperative intubation. RESULTS: Sixty-one patients underwent complete repair. Thirty-three patients underwent pulmonary artery plication (n=15) or reduction (n=18). The right ventricular outflow tract (RVOT) was reconstructed with valved conduit (n=31), bioprosthetic valve (n=18), monocusp (n=8), or transannular patch (n=4). There were three perioperative and five late deaths. All perioperative deaths were in neonates and before 1995. Five- and ten-year survival was 93+/-4% and 87+/-5%. Mean ventilatory requirements for neonates, infants, and children > or =1 year were 36+/-35, 8+/-8, and 2.6+/-2.4 days (p<0.0001). On multivariable analysis, significant factors associated with prolonged ventilation were neonates (p<0.0001) and preoperative mechanical ventilation (p=0.088). Eight airway reinterventions were needed in seven infants with persistent postoperative airway compromise, pulmonary artery suspension (n=4), innominate artery suspension (n=2), and lobectomy (n=2). Freedom from RVOT reoperation was 89+/-5% and 59+/-9% at 5 and 10 years. There were no significant risk factors for time-related survival or RVOT reoperation on multivariable analysis. CONCLUSIONS: In contrast to children and adults with TOF/APV, neonates and small infants presenting with respiratory symptoms require prolonged ventilation and additional reinterventions for airway compression. Our current surgical approach which includes reduction and suspension of pulmonary arteries, reconstruction of a competent RVOT, and aggressive postoperative ventilatory management to relieve airway obstruction offers satisfactory outcomes.

Abnormalities, Multiple↗

PubMed2006

Management and outcomes of double aortic arch in 81 patients.

OBJECTIVES: Double aortic arch is a common form of complete vascular ring, encircling both the trachea and esophagus, resulting in noncardiac morbidity. We sought to describe management and outcomes in a large single institution clinical series. PATIENTS AND METHODS: We reviewed the medical charts of all of the patients diagnosed with double aortic arch at age <18 years. Data regarding clinical presentation, anatomy, management, and outcomes were abstracted. RESULTS: We identified 81 patients (67% males) born between 1964 and 2005 and presenting at a median age of 5 months (range: birth to 10.3 years). Respiratory symptoms were present in 91%, including stridor in 77%. Gastrointestinal symptoms were present in 40%, with choking with feeds being most common. The dominant branch of the double aortic arch was right in 72%. Associated cardiac anomalies were present in 18%, with noncardiac anomalies in 7%. Repair was performed in 79 patients at a median age of 6 months. There were 2 deaths after surgical repair with no late deaths, with Kaplan-Meier survival estimates of 96% at 5 years. Postoperative complications included chylothorax in 9%. Only 1 patient required reoperation. The most common symptoms at most recent follow-up were respiratory (54%) followed by gastrointestinal symptoms (6%). Postoperative tracheal stenosis was documented in 14%, with tracheomalacia in 7%. There were no late reoperations and no evidence of aortic arch obstruction. CONCLUSIONS: Outcomes are excellent after repair of double aortic arch, although persistent respiratory symptoms are frequent and probably associated with previous compression-related maldevelopment of the trachea and major airways.

Aorta, Thoracic↗

PubMed2006

Can pulmonary conduit dysfunction and failure be reduced in infants and children less than age 2 years at initial implantation?

OBJECTIVES: We sought to examine risk factors for pulmonary conduit failure or dysfunction in infants less than age 2 years at initial implantation. METHODS: From 2002 to 2005, 241 children at 17 institutions were discharged alive after initial pulmonary conduit insertion. Initial conduit type was pulmonary allograft in 37%, aortic allograft in 29%, bovine jugular venous valved conduit in 25%, porcine heterograft in 2%, and decellularized allograft in 7%. Parametric hazard analysis determined time-related prevalence and associated risk factors for pulmonary conduit intervention and explantation. Serial echocardiographic measurements after conduit implant were analyzed by mixed regression models. RESULTS: There were 89 first conduit-related interventions after discharge and 37 initial conduit explants were performed. First conduit intervention occurred at a constant rate, with a prevalence of 58% at 3 years from initial implant. Pulmonary conduit explantation (30% at 3 years) was characterized by an early-rising risk, suggesting that catheter-based intervention effectively blunts this early initial risk. Common risk-factors for first conduit intervention and explantation were smaller conduit Z-score and younger age at initial conduit implant, and the presence of pulmonary arborization abnormalities or stenoses. Pulmonary conduit peak gradient and regurgitation progressed nonlinearly in all patients over time. Gradient progressed more rapidly in children with aortic allografts and when initial conduit Z-score was less than +1 or more than +3. Pulmonary conduit regurgitation also progressed more rapidly in children with initial conduit Z-score greater than +3 and in those without jugular venous valved conduits, especially aortic allografts. CONCLUSIONS: Pulmonary conduit durability and hemodynamic function in patients undergoing initial conduit insertion at less than age 2 years can be improved by using pulmonary conduits with Z-scores between +1 and +3.

Blood Vessel Prosthesis↗

PubMed2006

Independent factors associated with mortality, reintervention, and achievement of complete repair in children with pulmonary atresia with ventricular septal defect.

OBJECTIVES: We described morphologic characteristics, particularly pulmonary anatomy, and determined the prevalence of definitive end states and their determinants in children with pulmonary atresia associated with ventricular septal defect (PAVSD). BACKGROUND: Pulmonary atresia associated with ventricular septal defect represents a broad morphologic spectrum that greatly influences management and outcomes. METHODS: From 1975 to 2004, 220 children with PAVSD presented to our institution. Blinded angiographic review (n = 171) characterized bronchopulmonary segment arterial supply. RESULTS: A total of 185 patients underwent surgery, and repair was definitive in 75%. Initial operations included systemic-pulmonary artery shunt in 57%, complete primary repair in 31%, or right ventricular outflow tract reconstruction in 12%. Based on angiographic review, 118 patients had simple PAVSD and 53 patients had PAVSD with major aortopulmonary collateral arteries (MAPCAs). Overall survival from initial operation was 71% at 10 years. Risk factors for death after initial operation included younger age at repair, earlier birth cohort, fewer bronchopulmonary segments supplied by native pulmonary arteries, and initial placement of a systemic-pulmonary artery shunt. Competing-risks analysis for initially palliated patients predicted that after 10 years, 68% achieved complete repair (with associated factors including later birth cohort and more bronchopulmonary segments supplied by native pulmonary arteries), 22% died without repair, and 10% remained alive without repair. Reoperations after complete repair occurred in 38 children (27%), with risk factors including older age at palliation, MAPCAs, and more segments supplied by collaterals. CONCLUSIONS: Outcomes in children with PAVSD have improved over time, and are better in completely repaired cases. Bronchopulmonary arterial supply is an important determinant of mortality, achievement of definitive repair, and post-repair reoperation.

Adolescent↗

PubMed2006

Nutrition and exercise environment available to outpatients, visitors, and staff in Children's hospitals in Canada and the United States.

BACKGROUND: Children's hospitals should advocate for children's health by modeling optimum health environments. OBJECTIVES: To determine whether children's hospitals provide optimum health environments and to identify associated factors. DESIGN: Telephone survey. SETTING: Canadian and US hospitals with accredited pediatric residency programs. PARTICIPANTS: Food services directors or administrative dietitians. MAIN OUTCOME MEASURES: Health environment grades as determined for 4 domains quantifying (1) the amount of less nutritious food sold at cafeterias (cafeteria grade), (2) the presence of fast food outlets (outlet grade), (3) the amount of nutritious food alternatives available (healthful alternative grade), and (4) the presence of patient obesity or employee exercise programs (program grade). RESULTS: The overall response rate was 87%. Compared with Canadian hospitals, US hospitals had more food outlets (89% vs 50%) and more snack/beverage vending machines (median, 16 vs 12) (P = .001 for both), despite equivalent consumer numbers. External companies managed more outlets at US vs Canadian hospitals (65% vs 14%; P = .01), and, generally, US hospitals recuperated more revenue from their outlets. Worst cafeteria grade was associated with US hospital location (odds ratio [OR], 8.9; 95% confidence interval [CI], 1.6-50; P = .01) and lower healthful alternative grade (OR, 0.016; 95% CI, 0.002-0.15; P<.001). Lower grade in any domain was related to whether hospitals received more revenue from noncafeteria food outlets (OR, 1.7; 95% CI, 1.06-2.72; P = .03) and the presence of more internally operated cafeterias (OR, 2.3 per cafeteria; 95% CI, 1.53-3.36; P<.001). CONCLUSIONS: Children's hospitals provide suboptimal health environments. Reliance on revenue may be an important motivating factor encouraging the adoption of outlets that serve less nutritious food.

Canada↗

PubMed2006

Transcatheter device versus surgical closure of ventricular septal defects: a clinical decision analysis.

OBJECTIVES: To compare transcatheter device versus surgical closure of ventricular septal defects (VSDs). METHODS: A clinical decision analysis was performed using standard gamble interviews. RESULTS: Device was initially preferred in 39 respondents (89%) and surgery in 5 (11%). The inherent difference in value between a perfect surgery and a perfect device (disutility of surgery) was equal to a mean risk of death of (1.2 +/- 2.2)%. Final values from decision analysis were initially equivalent. Values adjusted for estimated mortality, however, favored device (mean: 0.979 +/- 0.032) versus surgery (mean: 0.971 +/- 0.032), P = 0.052. When values were further adjusted for disutilities, device was significantly preferred (0.978 +/- 0.032) versus surgery (0.961 +/- 0.044), P < 0.005. Surgery would be preferred if the probability of major complications decreased below 5% or minor complications below 6%. CONCLUSIONS: When outcomes and their values are considered in a systematic manner, transcatheter device closure of suitable VSDs is favored over surgical repair.

Attitude of Health Personnel↗

PubMed2006

Hypothermic low-flow cardiopulmonary bypass impairs pulmonary and right ventricular function more than circulatory arrest.

BACKGROUND: Hypothermic circulatory arrest (HCA) is used during surgical treatment of certain congenital heart defects. The possibility of ischemic neurologic injury associated with HCA has led some surgeons to use low-flow cardiopulmonary bypass (CPB) during the hypothermic interval (hypothermic low flow [HLF]). This study investigates the inflammatory response to HCA and HLF, and reports the consequences of this response on pulmonary and right ventricular function. METHODS: Piglets (3.1 to 6.6 kg) were cooled to 16 degrees to 18 degrees C using CPB, and randomized: HCA for 60 minutes (n = 7), or HLF (50 cc.kg(-1).min(-1)) for 60 minutes (n = 6). The piglets were rewarmed to 36 degrees C and weaned from CPB. Serum tumor necrosis factor-alpha (TNF-alpha) concentration, percent lung water, and pulmonary and cardiac function were measured before and after CPB. RESULTS: Tumor necrosis factor-alpha was higher after HLF (2,990.5 +/- 884.5 pg/mL), compared with HCA (347.6 +/- 89.2 pg/mL; p = 0.03). The percent lung water was higher after HLF (84.8% +/- 0.3%) than HCA (82.0% +/- 0.4%; p < 0.001). The alveolar to arterial oxygen gradient was worse after HLF (457 +/- 42 mm Hg) than HCA (285.8 +/- 45 mm Hg; p = 0.02). Pulmonary vascular resistance was greater after HLF (36.08 +/- 8.28 mm Hg.mL(-1).m(-2).min(-1)) than HCA (14.55 +/- 3.46 mm Hg. mL(-1).m(-2).min(-1); p = 0.049). The right ventricular pressure waveform peak derivative, corrected for systolic pulmonary artery pressure, was lower after HLF (14.1 +/- 1.4 sec(-1)), than HCA (23.8 +/- 2.7 sec(-1); p = 0.01). CONCLUSIONS: Hypothermic low flow extends exposure to CPB, and is associated with an increased inflammatory response compared with HCA. The greater inflammatory response after HLF may result in substantial nonneurologic morbidity in the postoperative period, demonstrated by pulmonary and right ventricular dysfunction. Interventions that attenuate the inflammatory response to CPB may prevent pulmonary and right ventricular dysfunction after HLF.

Animals↗

PubMed2006

Cardiac output augmentation during hypoxemia improves cerebral metabolism after hypothermic cardiopulmonary bypass.

BACKGROUND: Hypothermic circulatory arrest (HCA) impairs cerebral oxygen delivery (CDO2) and cerebral oxygen consumption (CMRO2), which are further reduced by perioperative hypoxemia. This study investigates if continuous hypothermic low-flow cardiopulmonary bypass (HLF) or intermittent hypothermic low-flow cardiopulmonary bypass (IHLF) can prevent reductions in CDO2 and CMRO2 during hypoxemia. METHODS: Eighteen neonatal piglets, cooled to 16 degrees to 18 degrees C with cardiopulmonary bypass (CPB), were randomly assigned into three groups: HCA, HLF (50 cc.kg(-1).min(-1)), or IHLF (1 minute of HLF for every 15 minutes of HCA). After 60 minutes of hypothermia, normothermic CPB (100 cc.kg(-1).min(-1)) was established and cerebral perfusion data measured at hyperoxemia (PaO2 150 to 250 mm Hg), hypoxemia (PaO2 50 to 60 mm Hg), and severe hypoxemia (PaO2 30 to 40 mm Hg), and with increased CPB flow (200 cc.kg(-1).min(-1)) during severe hypoxemia. RESULTS: The CMRO2 (in mL O2.100 g(-1).min(-1)) was lower after HCA (2.5 +/- 0.3), compared with HLF (4.1 +/- 0.5, p = 0.02) and IHLF (6.2 +/- 0.8, p = 0.002). Within groups, the change from hyperoxemia to severe hypoxemia resulted in decreased CMRO2: HCA (1.3 +/- 0.2, p = 0.004), HLF (3.0 +/- 0.5, p = 0.01), and IHLF (2.9 +/- 0.5, p = 0.01). During severe hypoxemia, increasing CPB flow (from 100 cc.kg(-1).min(-1) to 200 cc.kg(-1).min(-1)) improved CMRO2: HCA (1.9 +/- 0.5, p = 0.05), HLF (4.2 +/- 0.5, p = 0.05), and IHLF (7.4 +/- 0.5, p = 0.04). CONCLUSIONS: Hypoxemia reduces CDO2 and CMRO2 despite the method of hypothermic CPB. Increased CPB flow during hypoxemia can restore both CDO2 and CMRO2 to values found with hyperoxemia and slower CPB flows. Augmenting cardiac output during periods of perioperative hypoxemia may prevent cerebral injury after exposure to hypothermic cardiopulmonary bypass.

Animals↗

PubMed2006

Truncus arteriosus associated with interrupted aortic arch in 50 neonates: a Congenital Heart Surgeons Society study.

BACKGROUND: Patients with both interrupted aortic arch (IAA) and truncus arteriosus (TA) have worse outcomes than those with either lesion in isolation. We determined outcomes and associated factors in this rare group. METHODS: From 1987 to 1997, 50 (11%) of 472 neonates with IAA were identified with TA. Site of aortic arch interruption was distal to the left subclavian artery in 16% and between the left common carotid and subclavian artery in 84%. From the common arterial trunk, the pulmonary arteries arose from a main pulmonary trunk in 46%, common orifice in 22%, and separate orifices in 32%. At presentation, truncal valve stenosis was present in 12% and regurgitation in 22%. RESULTS: There were 34 deaths, with a single early hazard phase. Overall survival from admission was 44%, 39%, and 31% at 6 months, 1 year, and 10 years, respectively. One patient had primary cardiac transplantation and 4 died without any intervention. The IAA repair alone was performed in 7 patients, with single stage repair of both IAA and TA in 38 patients. Associated factors for overall time-related death include female gender (p < 0.001), type III TA (p < 0.001) and one institution (low-risk; p < 0.001). Results improved somewhat over time (p < 0.001). At 5 years after IAA repair only 28% were alive without arch repair intervention, and at 5 years after TA repair only 18% were alive without conduit reoperation. CONCLUSIONS: The combination of IAA and TA carries high early mortality, with high risk of reinterventions in survivors. One stage repair of both TA and IAA is the optimal management.

Abnormalities, Multiple↗

PubMed2006

Outcomes in 45 children with ductal origin of the distal pulmonary artery.

BACKGROUND: There are no large series describing the morphologic spectrum and the clinical outcomes of children with ductal origin of the distal pulmonary artery (PA). METHODS: Medical records were reviewed for all children presenting between 1970 and 2001. Angiograms were reviewed at presentation and at last available follow-up. RESULTS: Forty-five patients were identified with median presenting age of 14 days (range, birth to 6.5 years). Ductal origin of the distal PA occurred as an isolated finding in 16 patients (36%), with tetralogy of Fallot in 12 (27%), with pulmonary atresia-ventricular septal defect in 13 (29%), and with heterotaxy in 4 (9%). Diagnostic pulmonary venous wedge angiography was performed in 21 patients (47%). Surgical procedures were undertaken in 31 patients, and were initial systemic-ductal PA shunt in 13 patients, interposition graft in 6, direct anastomosis to the main PA in 2, ductal PA banding in 2, unifocalization of the ductal PA with complete or staged pulmonary atresia-ventricular septal defect repair in 7, and heart transplantation in 1 patient. Surgical revision was required in 3 patients and catheter interventions in 12 patients. Overall 20-year survival was 70% and was improved among patients without congestive heart failure at presentation (p = 0.08, hazard ratio: 2.81). Reconstruction of the ductal PA decreased the prevalence of pulmonary parenchymal hypoplasia (p < 0.001) and scoliosis at last available follow-up. CONCLUSIONS: Ductal origin of the distal PA is associated with important multisystem morbidity and mortality. Early diagnosis and repair of the ductal PA, especially in children presenting with pulmonary overcirculation, may improve outcomes.

Cardiac Surgical Procedures↗

PubMed2006

Outcomes after late reoperation in patients with repaired tetralogy of Fallot: the impact of arrhythmia and arrhythmia surgery.

BACKGROUND: We evaluated outcomes in patients requiring late reoperation after tetralogy of Fallot (ToF) repair to identify risk factors for arrhythmia and determine whether arrhythmia surgery decreased the risk of subsequent death or recurrent arrhythmia. METHODS: Review was performed of all ToF patients from 1969 to 2005 undergoing reoperation late (> 1 year) after repair. Patients with associated lesions, except pulmonary atresia, were included. A total of 249 patients had 278 reoperations. Procedures at initial reoperation included pulmonary valve replacement (PVR) in 217, ablation in 63, and tricuspid valve repair/replacement in 46. Pre-reoperative arrhythmias were present in 75, including supraventricular tachycardia (SVT) in 31, ventricular tachycardia (VT) in 34, and SVT+VT in 10 patients. RESULTS: Median age at reoperation was 23 years (range, 1 to 63). Ten-year survival after reoperation was 93%, and was independent of arrhythmia status (p = 0.86). Arrhythmia patients were characterized by older age at initial repair and at late reoperation, tricuspid and pulmonary regurgitation, and longer QRS duration (p < 0.001 for all). Risk factors for post-reoperative recurrent arrhythmia were longer QRS duration and not having PVR. Longer QRS duration, with a cut-point of more than 160 msec, was associated with recurrent SVT (p = 0.004). Supraventricular tachycardia ablation improved arrhythmia-free survival (75% versus 33%, p < 0.001) but VT ablation did not (96% versus 95%, p = 0.50). However, recurrent VT occurred in only 3 patients (10%). CONCLUSIONS: Late mortality in patients undergoing reoperation after ToF repair is not impacted by pre-reoperative arrhythmia. Prolongation of QRS identifies patients at risk for recurrent VT and SVT, but recurrent VT is uncommon. Early PVR, and surgical ablation in patients with SVT, decreases arrhythmic risk.

Adolescent↗

PubMed2006

Effects of circuit miniaturization in reducing inflammatory response to infant cardiopulmonary bypass by elimination of allogeneic blood products.

Conventional neonatal cardiopulmonary bypass requires the use of large volumes of allogeneic blood to prevent unacceptable hemodilution. Evidence is accumulating to suggest that the use of blood products during cardiopulmonary bypass has a negative effect on clinical recovery through inflammatory side effects. This would suggest an advantage for eliminating blood use in infant cardiopulmonary bypass through circuit miniaturization. In this article, we review the data supporting this rationale and provide the results from studies in our laboratory that emphasize the benefits of circuit miniaturization.

Age Factors↗

PubMed2006

Short and midterm results of aortic valve cusp extension in the treatment of children with congenital aortic valve disease.

BACKGROUND: We evaluated our experience with aortic valve cusp extension techniques to identify predictors of successful intraoperative repair and subsequent durability. METHODS: Twenty-two children (ages 5-18 years) underwent aortic cusp extension with autologous pericardium between 1999 and 2005. Sixteen children had previous surgical or percutaneous intervention. Ten children had bicuspid aortic valves. Cusp extensions were performed on 1 cusp in 3 patients, 2 cusps in 3, and 3 cusps in 16. Serial echocardiographic measures (n = 81) were obtained during a 5-year period and underwent blinded review. Longitudinal trajectories of ventricular and aortic valve function were modeled using mixed linear regression analysis. RESULTS: There was no hospital or late mortality. Five-year freedom from valve replacement was 75%. Comparison of preoperative and post-repair echocardiograms demonstrated reductions in aortic insufficiency (decreased in jet-width/aortic valve diameter ratio from 0.39 +/- 0.12 to 0.22 +/- 0.11; p < 0.0001), aortic stenosis (decreased in peak aortic valve gradient from 41 +/- 25 mm Hg to 29 +/- 15 mm Hg; p = 0.04), and left ventricular end-diastolic dimensions Z-score (decreased from 1.39 +/- 0.38 to 1.16 +/- 0.34; p < 0.001). During the follow-up period, post-repair jet-width and aortic valve diameter increased nonlinearly (p < 0.001). Patients with postoperative peak aortic gradients greater than 30 mm Hg had progression of aortic stenosis, whereas those with lesser postoperative peak gradients tended to regress during follow-up (p < 0.001). The decrement in Z-score of the left ventricular end-diastolic dimensions remained stable during the follow-up period. CONCLUSIONS: Aortic valve cusp extension can result in acceptable hemodynamic results with stabilization of left ventricular geometry. However, residual lesions are common and progression and regression of these lesions can be predicted based on echocardiographic data.

Adolescent↗

PubMed2006

Surgical management of aortopulmonary window associated with interrupted aortic arch: a Congenital Heart Surgeons Society study.

OBJECTIVE: The objective was to determine outcomes and risk factors of surgical management of patients with aortopulmonary window associated with interrupted aortic arch. METHODS: From 1987 to 1997, 472 neonates with interrupted aortic arch were enrolled prospectively from 33 institutions. Associated aortopulmonary window was present in 20 patients. Competing risk methodology determined the prevalence of reintervention for postrepair pulmonary artery and aortic arch obstruction. RESULTS: Interrupted aortic arch was type A in 17 patients and type B in 3 patients. Aortopulmonary window morphology was type I (n = 10), type II (n = 5), and type III (n = 5). Associated cardiovascular anomalies were common, including atrial septal defect (n = 13) and systemic venous anomalies (n = 3). Overall survival after initial admission was 91%, 86%, and 84% at 1, 5, and 10 years, respectively. Fifteen patients underwent single-stage repair, and 4 patients underwent staged repair. There was an increased prevalence of patch augmentation of the interrupted aortic arch anastomosis in lower-weight infants (2.3 kg vs 3.1 kg, P = .07). Competing risk analysis estimated that 5 years after repair, 51% had initial arch reintervention, 6% had initial pulmonary artery reintervention, and 43% were alive without reintervention. Reintervention for arch obstruction was more likely for those with interrupted aortic arch type B (P = .08) and for those with higher weight at initial repair (P = .003). CONCLUSIONS: Complete correction of aortopulmonary window in the setting of interrupted aortic arch can be performed with low mortality in the neonatal period. Reinterventions for aortic arch obstruction are the most frequent complication after repair, but pulmonary artery stenosis also occurs. Use of patch augmentation may reduce the need for subsequent arch reintervention.

Aorta, Thoracic↗

PubMed2006

Impact on outcomes after listing and transplantation, of a strategy to accept ABO blood group-incompatible donor hearts for neonates and infants.

BACKGROUND: Recent data suggest that ABO blood group-incompatible donor hearts are immunologically well tolerated in infants undergoing transplantation. METHODS: Competing-risks methodology was used to assess outcomes after listing and the impact of a strategy to accept heart grafts from any blood group donor for infants less than 18 months of age. RESULTS: From 1992 to 2002, there were 91 listing episodes in 84 patients (including 20 fetuses; 50% were male and 63% had congenital heart disease). Beginning in 1995, a strategy to accept ABO-incompatible organs was adopted. Competing-risks analysis showed that after 20 months 60% underwent transplantation, 18% died, and less than 1% were still listed; the remaining 21% were de-listed because of a change of surgical strategy (9%), improved clinical condition (8%), and deterioration to ineligibility (4%). Risk factors for transplantation included only a strategy to accept ABO-incompatible organs (P <.001). Risk factors for death included failure to accept ABO-incompatible organs (P =.002) and Canadian listing status 3 (P =.085) or 4 (P <.001). Multivariable parametric models were used to create competing risk predictions for outcomes specific to status and ABO-incompatible strategy. Higher status resulted in greater mortality regardless of strategy, although for any status, more patients underwent transplantation and fewer died using a strategy to accept ABO-incompatible organs. Parametric modeling of time-related freedom from death or retransplantation demonstrated no significant difference at 4 years posttransplantation (P =.78) for ABO-incompatible (74%) versus ABO-compatible transplants (72%). CONCLUSIONS: A strategy to accept ABO-incompatible donor hearts for infant transplantation significantly improves the likelihood of transplantation and reduces waiting list mortality while not adversely altering outcomes after transplantation.

ABO Blood-Group System↗

PubMed2006

Surgical repair of multiple muscular ventricular septal defects: the role of re-endocardialization strategy.

OBJECTIVE: Surgical repair of multiple muscular ventricular septal defects (Swiss cheese septum) is associated with important morbidity and mortality. We sought to examine factors associated with permanent heart block, early mortality, and time-related survival. Additionally, we evaluated a new approach, transatrial re-endocardialization of interventricular septum, to mitigate risk. METHODS: One hundred sixteen patients underwent surgery for multiple muscular ventricular septal defects (1982-2005), of whom 64 (55%) had associated cardiac anomalies. Twenty-seven consecutive patients (median age 0.54 years, range 15 days-7.2 years) underwent transatrial re-endocardialization (2002-2005). Forty-four percent had Swiss cheese septum (>4 defects). Multivariable regression analysis determined risk factors for pacemaker and survival. RESULTS: Operative mortality for the entire cohort was 9%. Risk factors for death were double-outlet right ventricle (odds ratio 44.7, P = .003), ventriculotomy (odds ratio 6.4, P = .03), and fewer multiple muscular ventricular septal defects repaired (odds ratio 4.7/defect, P = .04). Era mortalities differed: 16% for 1982 through 1990, 13% for 1990 through 1998, and 0% for 1999 through 2005, P = .006). Fourteen patients (12%) required a pacemaker. Time-related survivals at 1 and 10 years were 90% +/- 3% and 82% +/- 5%. Risk factors for death were double-outlet right ventricle (hazard ratio 8.3, P = .02) and longer bypass (hazard ratio 1.02/min, P = .02). In 27 re-endocardialization patients, a combined closure strategy to close 184 defects were applied: transatrial re-endocardialization (median 5, range 2-21), patch (median 1, range 0-4), and device (range 0-1). Post-repair ventricular function was good in 25 of 27 patients. The median number of residual defects was 1.5 (range 0-3), and median residual jet width on color Doppler was 2.3 mm (range 0-4.2 mm). One child required a pacemaker. There were no early or late deaths. CONCLUSIONS: Outcome of surgical repair of multiple muscular ventricular septal defects (Swiss cheese septum) has improved. Transatrial re-endocardialization strategy enables early complete or nearly complete obliteration of multiple muscular ventricular septal defects with minimal residual lesions (shunt, ventricular dysfunction). Long cardiopulmonary bypass duration is well tolerated. The incidence of permanent heart block has improved. Early echocardiographic and clinical outcomes are promising.

Adolescent↗

PubMed2006

Presentation, management and outcomes of thrombosis for children with cardiomyopathy.

BACKGROUND: Thrombosis in children with dilated and inflammatory cardiomyopathy is an unpredictable complication with potentially important morbidity. OBJECTIVE: To determine the prevalence, associated factors, management and outcomes of thrombosis in this setting. METHODS: Data were obtained from review of medical records. Factors associated with thrombosis and the impact on outcome were sought. RESULTS: From 1990 to 1998, 66 patients that presented with dilated cardiomyopathy were followed for a median interval of 1.4 years (range 0 to 9.79 years) from first presentation. Thrombosis was diagnosed in four patients at presentation and in four patients during follow-up. Thrombosis was noted in one additional patient at examination after death. The overall nine-year period prevalence of thrombosis was 14%. Anticoagulation was started at presentation in 31% of patients. The mean left ventricular ejection fraction at presentation was significantly lower in those given anticoagulation (19+/-8%) versus those who were not (32+/-15%; P < 0.001). The mean ejection fraction at presentation was similar in those patients with (25+/-10%) versus those without thrombosis (28+/-15%; P = 0.44). During follow-up, 11 patients died and seven underwent cardiac transplantation. Kaplan-Meier estimates of freedom from death or transplantation were 88% at three months, 81% at one year and 70% at five years. Survival free of transplantation was not affected by thrombosis. CONCLUSIONS: Thrombosis is common in children with cardiomyopathy, can occur at any time in the patients' clinical course and is not related to clinical features or survival free of transplantation. The relevance and prevention of thrombosis in this setting remains unclear.

Adolescent↗

PubMed2006

Surgery insight: late complications following repair of tetralogy of Fallot and related surgical strategies for management.

Biventricular correction of tetralogy of Fallot was devised more than 50 years ago. Current short-term outcomes are excellent. The potential for late complications is, however, an important concern for the growing number of postrepair survivors. Progressive pulmonary valve regurgitation leading to right heart failure and arrhythmia are centrally important problems faced by these patients. New techniques are, however, likely to change the future outcomes for postrepair survivors. These techniques include percutaneous valve replacement, arrhythmia ablation surgery, and strategies that emphasize preservation of the pulmonary valve even at the cost of leaving some residual valvular stenosis. The objectives of this Review are to outline the major complications that arise late after repair of tetralogy of Fallot, to describe the surgical approaches that have been developed to avoid and manage arising complications, and to briefly explore how novel treatment paradigms could change the future long-term outlook for patients following tetralogy repair.

Aortic Valve Insufficiency↗