Search PubMed⌕ Search

Biomedical subjects

Tara Karamlou

Publications and source records attributed to Tara Karamlou.

At least 19 recordsLinked to original sources
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

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

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

Results of concomitant aortic valve replacement and coronary artery bypass grafting in the VA population.

BACKGROUND AND AIM OF THE STUDY: Concomitant aortic valve replacement (AVR) and coronary artery bypass grafting (CABG) is an established risk factor for diminished postoperative survival. Results from a VA population were reviewed in order to determine factors influencing early and late survival. METHODS: Between 1993 and 2003, a total of 401 patients underwent AVR at the authors' institution. Of these patients, 249 (62%; mean age 70.6 years) had combined AVR and CABG. Surgical indications were primarily aortic valve pathology (group A: n = 168; 68%), primarily coronary artery disease (CAD) (group B: n = 55; 22%), and both severe aortic and coronary disease (group C: n = 26; 10%). In total, 177 patients (71%) received a bioprosthesis, and 72 (29%) received a mechanical valve. Short- and long-term outcomes were explored using univariate and multivariable hazard analyses. RESULTS: Overall operative mortality was 6.4%; mortality for groups A, B and C was 4.8%, 9.1% and 11.5%, respectively. On multivariable analysis, significant factors associated with early-phase mortality were NYHA class IV, diabetes, bioprosthetic valve and combined severe aortic and coronary disease. Survival at one and five years was 86% and 62%, respectively. Five-year survival for groups A, B and C was 71%, 63% and 54%, respectively. Significant associated factors for late-phase mortality were the presence of preoperative peripheral vascular disease (PVD) and cerebrovascular disease (CVD). Factors such as age, prior cardiac surgery, number of grafted coronary arteries, and/or effective orifice area index (EOAI) had no significant effect on outcome. CONCLUSION: Combined AVR/CABG is a marker for decreased survival. Pre-existing factors such as diabetes, PVD and CVD, as well as poor preoperative NYHA functional status, affected survival. Further investigation is needed to assess the influence of the severity of CAD and EOAI on survival. Thoughtful consideration of all these factors is essential for an accurate prediction of survival, and to determine the appropriate type of aortic prosthesis to be used.

Age Factors↗
PubMed2005

Outcomes and associated risk factors for aortic valve replacement in 160 children: a competing-risks analysis.

BACKGROUND: We sought to define patient characteristics, outcomes, and associated risk factors after aortic valve replacement (AVR) in children. METHODS AND RESULTS: Clinical records from children undergoing AVR from 1974 to 2004 at our institution were reviewed. Competing-risks methodology determined the time-related prevalence of 3 mutually exclusive end states: death, repeated replacement, and survival without subsequent AVR and their associated risk factors. Longitudinal echocardiographic data were analyzed by mixed linear-regression models. Children (n=160) underwent 198 AVRs, with 33 having >1. Competing-risks analysis predicted that 10 years from the initial AVR, 19% had died without subsequent AVR, 34% underwent a second AVR, and 47% remained alive without replacement. Risk factors for death without a second AVR included lower weight (P<0.001) and younger age at AVR (P=0.04), performance of aortic arch reconstruction together with AVR (P=0.03), and nonautograft use (P=0.03). Risk factors for a second AVR included earlier operation year (P=0.04) and implantation of a bioprosthetic or homograft valve (P=0.004). Analysis of serial echocardiographic measurements showed that pulmonary autograft use was associated with slower progression of peak aortic gradient (P=0.002), smaller left ventricular dimension (P=0.04), and decreased prevalence of aortic regurgitation (P=0.04). CONCLUSIONS: Mortality and repeated valve replacement are common after initial AVR in children, especially in younger patients and those with bioprosthetic or homograft valves. Pulmonary autograft use is associated with decreased mortality, slower gradient progression, and smaller left ventricular dimension.

Adolescent↗
PubMed2005

Matching procedure to morphology improves outcomes in neonates with tricuspid atresia.

OBJECTIVE: This study was undertaken to characterize morphologic substrate of tricuspid atresia with ventriculoarterial concordance and discriminate management strategies that lead to successful definitive repair. METHODS: From 1999 to 2004, a total of 150 babies with type I tricuspid atresia were enrolled from first diagnosis at 26 institutions. Antegrade pulmonary blood flow was absent in 19%, restricted in 54%, and unrestricted in 28%. Competing-risk methodology determined the time-related prevalence and risk factors for death versus cavopulmonary anastomosis and subsequent death versus Fontan completion. RESULTS: Overall 5-year survival was 86%. Initial palliation included systemic-pulmonary arterial shunt in 64%, pulmonary artery banding in 11%, and cavopulmonary anastomosis in 24%. Median age at cavopulmonary anastomosis was 6 months, with 83% undergoing bidirectional Glenn shunt and 17% undergoing hemi-Fontan procedure. By the age of 2 years, 89% had cavopulmonary anastomosis, 6% were dead, and 4% remained alive without cavopulmonary anastomosis. Risk factors for death without cavopulmonary anastomosis included presence of mitral regurgitation (P = .03) and palliation with systemic-pulmonary arterial shunts not originating from the innominate artery (P = .04). Factors associated with decreased transition rate to cavopulmonary connection included patient variables (younger admission age to a participating institution, noncardiac anomalies) and procedural variables (larger systemic-pulmonary arterial shunt diameter, previous palliation). Of patients undergoing cavopulmonary anastomosis, 75% had undergone a Fontan operation within 3 years. CONCLUSION: Smaller shunt size and decreased pulmonary blood flow decrease mortality after initial palliation and increase the rate of successful transition to cavopulmonary anastomosis. Outcomes can be improved by placing smaller shunts from the innominate artery, especially in patients with any mitral regurgitation.

Cardiac Surgical Procedures↗
PubMed2005

The use of live three-dimensional Doppler echocardiography in the measurement of cardiac output: an in vivo animal study.

OBJECTIVES: The purpose of this study was to investigate whether cardiac output (CO) could be accurately computed from live three-dimensional (3-D) Doppler echocardiographic data in an acute open-chested animal preparation. BACKGROUND: The accurate measurement of CO is important in both patient management and research. Current methods use invasive pulmonary artery catheters or two-dimensional (2-D) echocardiography or esophageal aortic Doppler measures, with the inherent risks and inaccuracies of these techniques. METHODS: Seventeen juvenile, open-chested pigs were studied before undergoing a separate cardiopulmonary bypass procedure. Live 3-D Doppler echocardiography images of the left ventricular outflow tract and aortic valve were obtained by epicardial scanning, using a Philips Medical Systems (Andover, Massachusetts) Sonos 7500 Live 3-D Echo system with a 2.5-MHz probe. Simultaneous CO measurements were obtained from an ultrasonic flow probe placed around the aortic root. Subsequent offline processing using custom software computed the CO from the digital 3-D Doppler DICOM data, and this was compared to the gold standard of the aortic flow probe measurements. RESULTS: One hundred forty-three individual CO measurements were taken from 16 pigs, one being excluded because of severe aortic regurgitation. There was good correlation between the 3-D Doppler and flow probe methods of CO measurement (y = 1.1x - 9.82, R(2) = 0.93). CONCLUSIONS: In this acute animal preparation, live 3-D Doppler echocardiographic data allowed for accurate assessment of CO as compared to the ultrasonic flow probe measurement.

Animals↗
PubMed2005

Extracorporeal life support in neonates, infants, and children after repair of congenital heart disease: modern era results in a single institution.

BACKGROUND: Extracorporeal life support has assumed a very effective role in the support of patients with refractory heart failure after repair of congenital heart disease, with hospital survival between 37% and 42%. We reviewed our results of different applications of extracorporeal life support in the last 2 years. METHODS: Between January 2001 and October 2003, 671 patients underwent surgery for congenital heart disease at our institution. We retrospectively reviewed the hospital and clinic charts of the patients who required extracorporeal life support postoperatively, and studied the factors associated with survival. RESULTS: Thirty-six patients (5.36%) received extracorporeal life support after surgery, between 1 day and 8 years of age (age < 30 days, n = 34). We divided the patients into four groups. Group 1 consisted of 13 patients who were electively placed on ventricular support without an oxygenator (univentricular assist device) after repair of single-ventricle disease. Group 2 consisted of 16 patients who required extracorporeal membrane oxygenation after surgery for failed hemodynamics. Group 3 consisted of 2 patients who required left ventricle support (left ventricular assist device) after surgery for two-ventricle disease but who did not require biventricular (extracorporeal membrane oxygenation) support. Group 4 consisted of 5 patients who required conversion from ventricular assist device to extracorporeal membrane oxygenation. Overall, 28 patients were weaned successfully (78%), and 24 survived to discharge (67%). Hospital survival in groups 1, 2, 3, and 4 was 100%, 50%, 100%, and 20%, respectively. Univariate factors associated with survival were age, weight, ventricular assist device type, duration, single-ventricle disease, reexploration, number of complications, and specific complications such as sepsis, renal failure, and pulmonary failure. CONCLUSIONS: Extracorporeal life support utilization was expanded to include different applications with different outcomes. The extracorporeal life support registry should be altered to reflect those changes.

Assisted Circulation↗
PubMed2005

Using a miniaturized circuit and an asanguineous prime to reduce neutrophil-mediated organ dysfunction following infant cardiopulmonary bypass.

BACKGROUND: Contemporary infant cardiopulmonary bypass circuits require a blood prime. Blood, especially when stored, generates an inflammatory response, and may contribute to organ dysfunction following cardiopulmonary bypass. We determined whether using a miniaturized circuit and an asanguineous prime attenuated the post-bypass inflammatory response, and improved right ventricular and pulmonary function. METHODS: Sixteen infant piglets were placed into 3 groups based on prime components: group I (fresh blood), group II (stored blood), and group III (miniaturized circuit and asanguineous prime). Piglets were placed on cardiopulmonary bypass (100 mL.kg(-1).min(-1)), cooled to 18 degrees C, and underwent continuous perfusion (50 mL.kg(-1).min(-1)) for 30 minutes. They were rewarmed and separated from bypass. Serum tumor necrosis factor-alpha, right ventricular function, and pulmonary function were measured before and 30 minutes after bypass. Neutrophil priming activity in fresh and stored donor blood was also assessed. RESULTS: Animals in group III had significantly improved cardiopulmonary function than the groups receiving blood (right ventricular cardiac index [mL.kg(-1).min(-1)]: group I [18.8 +/- 4.8], group II [21.5 +/- 6.2], and group III [81.2 +/- 11.4], p < 0.001; and pulmonary vascular resistance index [dynes.mL(-1).kg(-1)]: group I [1169 +/- 409], group II [1610 +/- 486], and group III [214 +/- 63], p = 0.03). Tumor necrosis factor-alpha (pg.mL(-1)) was lower in group III (1465 +/- 39) than in the groups receiving blood (3940 +/- 777), p = 0.002. Neutrophil priming activity (nmol.min(-1)) was also higher in stored blood (3.7 +/- 6) than in fresh blood (1.9 +/- 0.2), p = 0.02. CONCLUSIONS: We have devised a unique miniaturized circuit that allows an asanguineous prime without hemodilution in an infant swine model. The employment of this circuit attenuates the post-bypass inflammatory response and has salutary effects on cardiopulmonary function.

Animals↗
PubMed2005

The influence of valve physiology on outcome following aortic valvotomy for congenital bicuspid valve in children: 30-year results from a single institution.

OBJECTIVE: Aortic valvotomy is widely used for the treatment of congenital aortic stenosis in children. We sought to evaluate whether the predominant post-valvotomy physiology, aortic insufficiency (AI) or aortic stenosis (AS) independently affected patient outcome. METHODS: From 1972-2002, 57 children with congenital aortic stenosis underwent valvotomy. We divided age-matched patients with residual lesions based on their predominant pathology into three groups: Group I (n=14), patients with moderate AI; Group II (n=14), patients with moderate AS, and Group III (n=14), patients with combined AI and AS. Fifteen patients with severe AI or mild residual lesions following valvotomy were excluded from analysis. RESULTS: mean freedom from aortic valve replacement (AVR) was 11.2+/-1.7 years in Group I and 21.5+/-3.9 years in Group II, P=0.05. AVR was required in 11 patients (79%) in Group I vs. only 5 (36%) in Group II, P=0.05. Group III was intermediate, with 9 (64%) requiring AVR. At the time of AVR, patients with aortic stenosis had significantly higher fractional shortening % than those with insufficiency or combined lesions, (Group 1: 38.2+/-7.9 vs. Group II: 46.3+/-5.5 vs. Group III: 39.2+/-3.7, P=0.007). Patients in Group II also had less severely dilated ventricles (mm) than those in the other groups, (Group 1: 50.2+/-12.5 vs. Group II: 39.5+/-8.3 vs. Group III: 49.0+/-8.1, P=0.030). CONCLUSIONS: patients with predominant AI following valvotomy are more likely to need AVR sooner than those with residual stenosis without AI. Therefore, cautious use of repeat valvotomy using maneuvers to avoid AI (small balloons), may prolong freedom from aortic valve replacement in those patients with significant residual AS.

Aortic Valve↗
PubMed2005

Oversizing pulmonary homograft conduits does not significantly decrease allograft failure in children.

OBJECTIVE: Placement of oversized pulmonary ventricle-pulmonary artery conduits is routinely performed to decrease conduit failure in children. However, this practice has recently been challenged as somatic outgrowth may not be the main determinant of allograft failure in children. Our objective was to determine whether placement of oversized homografts for extracardiac pulmonary ventricle (PV) outflow tract reconstruction improves longevity in young children. METHODS: We reviewed 102 consecutive PV-PA conduits inserted in 70 patients less than 18 years between 1984 and 2003. Conduits placed in an anatomic position (n=23) as part of a Ross operation, were excluded. Conduits were initially stratified into two age groups: Group 1, those placed in patients 10 years. Normalization of conduit size to patient's body surface area at the time of insertion (z-value) was then performed to divide the conduits into oversized (O/S) and non-oversized (NO/S) groups. Determinants of conduit failure and allograft longevity were then compared between groups. RESULTS: Seventy-nine extracardiac conduits were placed, and 57 of these were in patients under 10 years of age. The majority had a diagnosis of tetralogy of Fallot (n=38), truncus arteriosus (n=19), pulmonary atresia with ventricular septal defect (n=12), or D-TGA with pulmonary stenosis and ventricular septal defect (n=7). Thirty-seven conduits were oversized (O/S) based on z-value, and 42 were non-oversized (NO/S), and the mean age at initial homograft placement was 7.0+/-7.5 years. Overall, oversizing conferred no significant advantage with respect to actuarial freedom from homograft replacement at 1, 5, or 10 years (96, 79, and 21%, O/S vs 93, 60, and 24%, NO/S), P=0.44. Oversizing was more frequent in Group 1 than Group 2 (53 vs 32%), and conduit failure was also more frequent with 49% requiring reoperation during the study period vs 38% in Group 2. In the subset of patients <or=10 years, both homograft explantation rate (50% O/S vs 48% NO/S) and median interval to conduit failure were similar between the O/S and NO/S patients (7.1 vs 4.8 years), P=0.340. Risk factors for conduit failure identified in multivariable regression analysis included the presence of pulmonary artery branch stenosis, lack of previous definitive repair, a diagnosis of pulmonary atresia, the need for percutaneous intervention. CONCLUSIONS: There is no significant benefit to placement of an oversized PV-PA homograft in this series of patients from a single institution. Even in young patients with rapid somatic growth, normalizing extracardiac allografts to BSA provides excellent conduit longevity and outcomes.

Adolescent↗