Pirooz Eghtesady

Interstage mortality after the Norwood procedure: Results of the multicenter Single Ventricle Reconstruction trial

OBJECTIVEnFor infants with single ventricle malformations undergoing staged repair, interstage mortality is reported at 2% to 20%. The Single Ventricle Reconstruction trial randomized subjects with a single morphologic right ventricle undergoing a Norwood procedure to a modified Blalock-Taussig shunt (MBTS) or a right ventricle-to-pulmonary artery shunt (RVPAS). The aim of this analysis was to explore the associations of interstage mortality and shunt type, and demographic, anatomic, and perioperative factors.nnnMETHODSnParticipants in the Single Ventricle Reconstruction trial who survived to discharge after the Norwood procedure were included (nxa0=xa0426). Interstage mortality was defined as death postdischarge after the Norwood procedure and before the stage II procedure. Univariate analysis and multivariable logistic regression were performed adjusting for site.nnnRESULTSnOverall interstage mortality was 50 of 426 (12%)-13 of 225 (6%) for RVPAS and 37 of 201 (18%) for MBTS (odds ratio [OR] for MBTS, 3.4; Pxa0<xa0.001). When moderate to severe postoperative atrioventricular valve regurgitation (AVVR) was present, interstage mortality was similar between shunt types. Interstage mortality was independently associated with gestational age less than 37 weeks (OR, 3.9; Pxa0=xa0.008), Hispanic ethnicity (OR, 2.6; Pxa0=xa0.04), aortic atresia/mitral atresia (OR, 2.3; Pxa0=xa0.03), greater number of post-Norwood complications (OR, 1.2; Pxa0=xa0.006), census block poverty level (Pxa0=xa0.003), and MBTS in subjects with no or mild postoperative AVVR (OR, 9.7; Pxa0<xa0.001).nnnCONCLUSIONSnInterstage mortality remains high at 12% and is increased with the MBTS compared with the RVPAS if postoperative AVVR is absent or mild. Preterm delivery, anatomic, and socioeconomic factors are also important. Avoiding preterm delivery when possible and close surveillance after Norwood hospitalization for infants with identified risk factors may reduce interstage mortality.

Lower weight-for-age z score adversely affects hospital length of stay after the bidirectional Glenn procedure in 100 infants with a single ventricle

OBJECTIVEnPoor growth has been described in infants with a single ventricle; however, little is known regarding its effect on surgical outcomes. We sought to assess the effect of nutritional status at the time of the bidirectional Glenn procedure on short-term outcomes.nnnMETHODSnWe performed a retrospective case series of children who underwent the bidirectional Glenn procedure at our institution between January 2001 and December 2007. Anthropometric measurements were recorded at the time of neonatal admission and the bidirectional Glenn procedure. Data from preoperative echocardiograms and cardiac catheterization were recorded. The primary outcome variable was length of hospital stay.nnnRESULTSnData on 100 infants were included for analysis. Age at the time of the bidirectional Glenn procedure was 5.1 months (range, 2.4-10 months). The median weight-for-age z score at birth was -0.4 (range, -2.6 to 3.2), and by the time of the bidirectional Glenn procedure, it had decreased to -1.3 (range, -3.9 to 0.6). In multivariable modeling longer postoperative hospital stays were predicted by lower weight-for-age z score (P = .02), younger age (P < .001), being fed through a gastrostomy tube (P = .01), and undergoing concomitant aortic arch reconstruction (P < .001) at the time of the bidirectional Glenn procedure.nnnCONCLUSIONSnThere is suboptimal weight gain between neonatal discharge and the bidirectional Glenn procedure. A lower weight-for-age z score and younger age at the time of the bidirectional Glenn procedure affects length of hospital stay independent of hemodynamic or echocardiographic variables.

Risk Factors for Mortality and Morbidity After the Neonatal Blalock-Taussig Shunt Procedure

BACKGROUNDnPerioperative advances have led to significant improvements in outcomes after many complex neonatal open heart procedures. Whether similar improvements have been realized for the modified Blalock-Taussig shunt, the most common palliative neonatal closed-heart procedure, is not known.nnnMETHODSnData were abstracted from The Society of Thoracic Surgeons Congenital Heart Surgery Database (2002 to 2009). Inclusion criteria were all neonates who received a modified Blalock-Taussig shunt with or without cardiopulmonary bypass, and with or without concomitant ligation of a patent ductus arteriosus. Discharge mortality was the primary end point. A composite morbidity end point one or more of the following: postoperative extracorporeal membrane oxygenation, low cardiac output, or unplanned reoperation. Associations with patient and procedural variables were assessed with univariable and multivariable analyses.nnnRESULTSnThe inclusion criteria were met by 1273 patients. The discharge mortality rate was 7.2%, and composite morbidity, as defined, was 13.1%. Primary diagnoses were classified as (1) those potentially amenable to biventricular repair (62%), (2) functionally univentricular hearts (22%), and (3) pulmonary atresia with intact ventricular septum (PA/IVS; 14%), and miscellaneous (2%). Discharge mortality stratified by primary diagnoses was PA/IVS (15.6%), functionally univentricular hearts (7.2%), and diagnoses potentially amenable to biventricular repair (5.1%). Need for preoperative ventilatory support, diagnosis of PA/IVS or functionally univentricular hearts, and any weight less than 3 kg, were risk factors for death. Preoperative acidosis or shock (resolved or persistent) and diagnosis of PA/IVS or functionally univentricular hearts were predictors of composite morbidity. Nearly 33% of the deaths occurred within 24 hours postoperatively, and 75% within the first 30 days.nnnCONCLUSIONSnThe mortality rate after the neonatal modified Blalock-Taussig shunt remains high, particularly for infants weighing less than 3 kg and those with the diagnosis of PA/IVS.

Cause, timing, and location of death in the Single Ventricle Reconstruction trial

OBJECTIVESnThe Single Ventricle Reconstruction trial randomized 555 subjects with a single right ventricle undergoing the Norwood procedure at 15 North American centers to receive either a modified Blalock-Taussig shunt or right ventricle-to-pulmonary artery shunt. Results demonstrated a rate of death or cardiac transplantation by 12 months postrandomization of 36% for the modified Blalock-Taussig shunt and 26% for the right ventricle-to-pulmonary artery shunt, consistent with other publications. Despite this high mortality rate, little is known about the circumstances surrounding these deaths.nnnMETHODSnThere were 164 deaths within 12 months postrandomization. A committee adjudicated all deaths for cause and recorded the timing, location, and other factors for each event.nnnRESULTSnThe most common cause of death was cardiovascular (42%), followed by unknown cause (24%) and multisystem organ failure (7%). The median age at death for subjects dying during the 12 months was 1.6 months (interquartile range, 0.6 to 3.7 months), with the highest number of deaths occurring during hospitalization related to the Norwood procedure. The most common location of death was at a Single Ventricle Reconstruction trial hospital (74%), followed by home (13%). There were 29 sudden, unexpected deaths (18%), although in retrospect, 12 were preceded by a prodrome.nnnCONCLUSIONSnIn infants with a single right ventricle undergoing staged repair, the majority of deaths within 12 months of the procedure are due to cardiovascular causes, occur in a hospital, and within the first few months of life. Increased understanding of the circumstances surrounding the deaths of these single ventricle patients may reduce the high mortality rate.

Association of Pulmonary Conduit Type and Size With Durability in Infants and Young Children

BACKGROUNDnTreatment of congenital heart disease may include placement of a right ventricle to pulmonary artery conduit that requires future surgical replacement. We sought to identify surgeon-modifiable factors associated with durability (defined as freedom from surgical replacement or explantation) of the initial conduit in children less than 2 years of age at initial insertion.nnnMETHODSnSince 2002, 429 infants were discharged from 24 Congenital Heart Surgeons Society member institutions after initial conduit insertion. Parametric hazard analysis identified factors associated with conduit durability while adjusting for patient characteristics, the institution where the conduit was inserted, and time-dependent interval procedures performed after conduit insertion but before replacement/explantation.nnnRESULTSnIn all, 138 conduit replacements (32%) and 3 explantations (1%) were performed. Conduit durability at a median follow-up of 6.0 years (range, 0.1 to 11.7) was 63%. After adjusting for interval procedures and institution, placement of a conduit with smaller z-score was associated with earlier replacement/explantation (p = 0.002). Moreover, conduit durability was substantially reduced with aortic allografts (p = 0.002) and pulmonary allografts (p = 0.03) compared with bovine jugular venous valved conduits (JVVC). The JVVC were 12 mm to 22 mm in diameter at insertion (compared with 6 mm to 20 mm for allografts); therefore, a parametric propensity-adjusted analysis of patients with aortic or pulmonary allografts versus JVVC with diameter of 12 mm or greater was performed, which verified the superior durability of JVVC.nnnCONCLUSIONSnPulmonary conduit type and z-score are associated with late conduit durability independent of the effects of institution and subsequent interval procedures. Surgeons can improve long-term conduit durability by judiciously oversizing, and by selecting a JVVC.

Outcomes of the bidirectional Glenn procedure in patients less than 3 months of age

OBJECTIVEnThe bidirectional Glenn procedure is a well-established procedure performed as part of the single-ventricle palliation pathway. Numerous studies have highlighted the potential benefits of an early BDG procedure. The ideal age to perform the BDG procedure, however, remains uncertain. We report our experience with the BDG procedure in patients younger than 3 months.nnnMETHODSnOne hundred sixty-nine consecutive patients from 1998 to 2007 undergoing the BDG procedure were divided into 2 groups: younger than 3 months (n = 20) and older than 3 months. The groups were compared for 26 variables. All data were analyzed with Kaplan-Meier survival analysis and the Cox proportional hazard regression test to assess the probability of survival after the BDG procedure in both groups. A stepwise regression analysis was performed for identification of independent factors for postoperative oxygen saturation at hospital discharge.nnnRESULTSnThe groups were comparable, with an equal distribution of patients with right-sided or left-sided single-ventricle anatomy. Although intensive care unit length of stay, ventilation time, and hospital length of stay were longer in the younger group, room air oxygen saturations at discharge, both early and late mortality, and time to the Fontan procedure were similar between groups. The independent variables found for death after the BDG procedure were preoperative mean pulmonary artery pressure, atrioventricular valve regurgitation, and postoperative oxygen saturations at hospital discharge. Survival in patients with hypoplastic left heart syndrome was comparable between groups after 5 years of follow-up.nnnCONCLUSIONnThe BDG procedure is feasible and safe in patients as young as 2 months of age, with early and late mortality equivalent to that seen in older patients.

Predictors of poor weight gain in infants with a single ventricle

OBJECTIVEnTo assess growth from the time of neonatal discharge to the time of performance of the bidirectional Glenn (BDG) procedure in infants with a single ventricle and determine predictors of poor growth.nnnSTUDY DESIGNnWe performed a retrospective case series of infants who underwent the BDG procedure at our institution between January 2001 and December 2007 (n=102). Anthropometric and clinical data were recorded during neonatal hospitalization and before BDG. Outcome variables included weight-for-age z-score (WAZ) at the time of BDG and average daily weight gain between neonatal discharge and BDG.nnnRESULTSnMedian age at the time of BDG was 5.1 months (range, 2.4-10 months), and median WAZ was -0.4 (range, -2.6 to 3.2) at neonatal admission and -1.3 (range, -3.9 to 0.6) at the time of BDG. Non-Caucasian infants (P=.03) and those with lower WAZ at neonatal discharge (P<.0001) had a lower WAZ at BDG. Being formula-fed at neonatal discharge (P=.04), and having higher mean pulmonary arterial pressure (P=.04) and systemic oxygen saturation (P=.006) were associated with lower average daily weight gain between neonatal discharge and BDG.nnnCONCLUSIONSnInfants with a single ventricle have poor weight gain between neonatal discharge and BDG. Non-Caucasian infants and those with evidence of increased pulmonary blood flow are at particular risk for growth failure.

Low Weight-for-Age Z-Score and Infection Risk After the Fontan Procedure

BACKGROUNDnPoor growth is common in infants with a single ventricle. Lower weight-for-age z-score (WAZ) is associated with worse short-term outcome after bidirectional Glenn procedure. We sought to assess growth status at the time of the Fontan procedure and the effect of poor growth status on surgical outcomes.nnnMETHODSnThis retrospective case series examined children who underwent Fontan at our institution between January 2003 and December 2008. Weight and height were obtained at the time of admission for Fontan. Data from preoperative echocardiogram and cardiac catheterization were abstracted to document cardiac function and hemodynamic measurements. Outcome variables included ventilator time, chest tube duration, postoperative infections (bacteremia, mediastinitis, urinary tract infection, gastroenteritis, or culture-positive pneumonia), and length of hospital stay.nnnRESULTSnFifty-five patients were included for analysis. The median age at Fontan was 46 months (range, 18 to 72); median WAZ was -1.0 (-3.8 to +2.0), and height for age z-score was -1.1 (-3.7 to +1.5). The WAZ was less than -2.0 in 19% of patients. Multivariable modeling revealed that patients with a WAZ less than -2.0 (p=0.006) had a greater incidence of serious postoperative infections. The only factor predicting longer length of hospital stay was presence of a serious postoperative infection (p<0.0001). Ventilator time was predicted only by length of cardiopulmonary bypass (p=0.01). No factors were associated with longer chest tube duration.nnnCONCLUSIONSnGrowth failure in children with a single ventricle persists through presentation for Fontan. A WAZ less than -2.0 at Fontan is associated with a higher rate of serious postoperative infections, which are associated with longer length of hospital stay.

Factors Affecting Long-Term Risk of Aortic Arch Recoarctation After the Norwood Procedure

BACKGROUNDnThe purpose of this study was to identify factors predicting risk of aortic arch recoarctation after the Norwood procedure.nnnMETHODSnPatient records were reviewed retrospectively for consecutive patients who underwent the Norwood procedure from 1996 to 2005. Preoperative and intraoperative parameters were identified for analysis. Aortic arch recoarctation was defined by the need for catheter or surgical reintervention. Data were analyzed using survival analysis, with freedom from intervention as the outcome. Factors predicting need for reintervention were analyzed using Cox proportional hazards regression.nnnRESULTSnThirty-five recoarctations were observed in 117 patients (30%). Freedom from aortic arch reintervention at six months, one, three, and five years were 72%, 63%, 56%, and 52%, respectively. The majority of arch reinterventions occurred in the first six months (63%), involving either surgical (43%) or catheter (57%) techniques. The use of bovine pericardium showed the greatest risk for potential recoarctation (hazard ratio = 1.81 [0.90-3.64], p = 0.09). Age, gender, weight, ascending aortic diameter, ventricular morphology, primary anatomic diagnosis, and coarctation shelf resection were not found to be predictors of recoarctation.nnnCONCLUSIONSnMost interventions for aortic arch recoarctation after the Norwood procedure occur within the first six months of life. The type of patch material used for arch reconstruction appears to influence, most strongly, the long-term risk of aortic arch recoarctation.

Fetal Stress Response to Fetal Cardiac Surgery

BACKGROUNDnA deleterious fetal stress response, although not fully elucidated, may account for poor outcomes after experimental fetal cardiac surgery. We set out to characterize this fetal stress response and its potential role in placental dysfunction.nnnMETHODSnFifteen ovine fetuses at gestational day 100 to 114 were placed on extracorporeal support for 30 minutes and were then followed 2 hours after cardiopulmonary bypass. Fetal plasma samples were analyzed for vasopressin, cortisol, and beta-endorphin levels, and correlated to fetal hemodynamics and placental gas exchange.nnnRESULTSnUnique temporal patterns of response were seen in release of the three stress hormones. Vasopressin demonstrated the most profound and early response followed by cortisol and beta-endorphin, the latter continuing to rise in the post-bypass period. A sharp rise in fetal mean arterial pressure and placental vascular resistance strongly correlated with rising vasopressin levels. Post-bypass deterioration of fetal gas exchange and hemodynamics correlated with the ensuing rise in cortisol and beta-endorphin. Rising fetal lactate levels correlated with elevations in all three stress hormones.nnnCONCLUSIONSnFetal cardiopulmonary bypass leads to a profound, early rise in vasopressin concentrations that strongly correlates with placental dysfunction after fetal bypass. Vasopressin may play an important mechanistic role in pathogenesis of this placental dysfunction.