Does the External Pericardial Lateral Tunnel Fontan Pathway Enlarge to Accommodate Somatic Growth? A Preliminary Analysis.

Objectives: An ideal Fontan pathway should be capable of adapting to changes in circulatory demands. The external pericardial lateral tunnel Fontan (EPLTF) is constructed of viable, autologous tissue and may be capable of changing in size. We investigated the ability of the EPLTF to enlarge with increasing physiologic demands of somatic growth. Methods: Retrospective review of echocardiographic images for patients with a minimum of five years follow-up after EPLTF. Serial echocardiographic measurements of the EPLTF pathway were obtained at three distinct locations: the inferior vena cava junction with the EPLTF, midsection of the EPLTF, and cross-sectional area of the EPLTF visualized in a four-chamber view. Body surface area (BSA) was calculated at the time of each echocardiographic measurement. Changes in echocardiographic measurements over time were analyzed and compared with changes in BSA. Results: A total of 332 echocardiographic studies from 38 patients were reviewed. Significant enlargement of the EPLTF pathway is observed at the inferior vena caval junction (P < .001), midsection (P < .01), and cross-sectional area (P < .001). Repeated measures correlation between pathway measurements and BSA is highly significant (P < .001). Conclusions: The EPLTF pathway enlarges over time in correlation with increasing BSA. Further research is needed to define ideal pathway size, differentiate normal physiologic growth from pathologic enlargement, and correlate changes with clinical outcomes.

Milky pericardial effusion causing tamponade in a neonate after extracorporeal membrane oxygenation cannulation.

Cardiac tamponade is a known life-threatening complication of extracorporeal membrane oxygenation (ECMO), often secondary to hemopericardium from major vascular or cardiac perforation. We present the unique case of a neonate with a milky pericardial effusion causing tamponade after ECMO cannulation, managed successfully with pericardial window. Understanding ECMO physiology and its effect on the classic presentation of tamponade is critical and can prevent delays in diagnosis. While hemopericardium is most commonly seen in these cases, findings of a non-bloody, milky effusion should prompt further workup for infection, chylopericardium or total parenteral nutrition-associated pericardial effusion, as the appropriate management can mitigate immediate and potential long-term sequelae.

Does the pattern of bicuspid aortic valve leaflet fusion determine the success of the Ross procedure?

BACKGROUND: In addition to being associated with aortopathy, a bicuspid aortic valve (BAV) has been posed to be a risk factor for the dilation of the pulmonary autograft in the aortic position. The aim of this study is to assess the association between the subtype of native aortic valve leaflet fusion (right and noncoronary leaflets [R/N] vs right and left leaflets [R/L]) and autograft dilation and valve dysfunction after the Ross procedure. METHODS: We performed a retrospective review of 43 patients with BAV who underwent a Ross procedure in our center from 1993 to 2013. Serial transthoracic echocardiography was used to measure changes in autograft and ascending aortic diameter over time. The aortic diameter was measured at four levels, and Z values were computed. Aortic dilation was defined as a Z value greater than 3. RESULTS: The mean age at the time of the Ross procedure was 13.5 ± 9.2 years. R/L was the most prevalent native aortic valve subtype (R/L, n = 26, 61% vs R/N, n = 17, 39%). PreRoss procedure, aortic dilation was more frequent in patients with R/N fusion (P = .02), whereas the initial aortic valve gradient and grade of aortic insufficiency (AI) did not differ between the subgroups. At follow-up, (mean = 9.6 ± 4.3 years) dilation of the autograft and ascending aorta was seen more often in patients with R/N leaflet fusion (P = .03). Conversely, the prevalence of more than moderate AI was significantly higher in patients with R/L leaflet fusion (P = .03). There was no significant difference between groups among numbers of late reintervention on the aortic valve or root (P = .75); however the type of intervention varied by morphologic subtype. Patients with R/L fusion underwent more aortic valve replacements (AVRs) while patients with R/N fusion underwent more valve-sparing aortic root replacements. CONCLUSIONS: After Ross procedure, both groups of patients were likely to have a combination of dilation of the aortic root and the tubular portion of the ascending aorta at follow-up. Patients with R/L fusion were more likely to have a prevalence of root dilation, while patients with R/N fusion were more likely to have tubular ascending aorta dilation. The R/L phenotype is associated with a slightly more rapid dilation at follow-up and is more likely to have postoperative autograft insufficiency. This information may serve to guide patient and procedure selection for AVR.

Cervical left pulmonary artery.

We detail what we believe to be the first reported case of a congenital 'Cervical Left Pulmonary Artery' in which an aberrant left pulmonary artery courses cranially into the mid-cervical neck before descending back into the thorax to the left pulmonary hilum. Due to the location and course of the artery, we believe that this anomaly is likely due to a developmental error of the sixth pharyngeal arch. Ultimately, the use of a reconstructed 3D computed tomography image provided detailed characterization of the unique anatomical variant, aiding in a successful surgical repair of the defect.

Performance of SynerGraft Decellularized Pulmonary Allografts Compared With Standard Cryopreserved Allografts: Results From Multiinstitutional Data.

BACKGROUND: Structural deterioration of allografts over time is believed to be at least partly related to an immune response mounted against human leukocyte antigen specific to the transplanted tissue. SynerGraft (SG) processing (CryoLife, Kennesaw, GA) is a technology that decellularizes an allograft leaving only connective tissue, therefore, reducing immunogenicity and potentially increasing durability of the implant. METHODS: We performed a retrospective review of 163 SG patients and 124 standard allograft controls from 3 medical centers. Patient demographics were tabulated, and conduit stenosis and insufficiency were measured by echocardiography. RESULTS: There were 28 deaths (15 of 163 [9%] SG patients vs 13 of 124 [11%] standard patients; p = 0.72), but no deaths were attributed to structural failure of the conduit. The actuarial survival for SG vs standard cohorts was not different at 5 and 10 years. Among the 274 hospital survivors, 17% SG vs 42% standard had evidence for significant conduit dysfunction at the most recent follow-up or before conduit replacement. Freedom from conduit dysfunction was significantly worse at 10 years in the standard group (58%) than in the SG group (83%, p < 0.001). CONCLUSIONS: This study represents a multiinstitutional retrospective comparison of SG and standard cryopreserved allografts used in right ventricular outflow tract reconstruction in a broad range of patient ages. Our results demonstrate that at an intermediate-term to long-term follow-up, conduit dysfunction and pulmonary insufficiency and stenosis are higher among patients receiving standard allografts. We postulate that the improved durability of SG is related to decreased immunogenicity of the SG technology.

Pediatric Extracorporeal Membrane Oxygenation: An Introduction for Emergency Medicine Physicians.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) therapy has supported critically ill pediatric patients in the intensive care unit setting with cardiac and respiratory failure. This therapy is beginning to transition to the emergency department setting. OBJECTIVE OF REVIEW: This article describes the fundamentals of ECMO and familiarizes the emergency medicine physician with its use in critically ill pediatric patients. DISCUSSION: ECMO can be utilized as either venoarterial (VA) or venovenous (VV), to support oxygenation and perfusion in respiratory failure, sepsis, cardiac arrest, and environmental hypothermia.

The Association Between Aortic Valve Leaflet Morphology and Patterns of Aortic Dilation in Patients With Bicuspid Aortic Valves.

BACKGROUND: Dilation of the aorta is a frequent complication in patients with bicuspid aortic valves. The aim of this study was to determine the relationship between the subtype of leaflet fusion, right and noncoronary leaflet (R/N) fusion versus right and left leaflet (R/L) fusion, and the patterns of aortic dilation and valve dysfunction in young patients with bicuspid aortic valves. METHODS: We performed a retrospective review of 642 patients who presented with bicuspid aortic valves between 1994 and 2014. Of these patients, 210 (33%) had aortic dilation (z score >3) by echocardiogram. For each patient, the most recent study or the last study before intervention was reviewed. RESULTS: Median patient age was 15 years (range, 0 to 40 years) with patients with R/N fusion being younger. The most prevalent subtype was R/N fusion (R/N, n = 114, 54% versus R/L, n = 96, 46%). Dilation of the ascending aorta was seen more often in patients with R/N fusion (R/N, 88% versus R/L, 68%; p = 0.004), whereas the prevalence of dilation of the sinuses of Valsalva was significantly higher in patients with R/L fusion (R/L, 46% versus R/N, 20%; p = 0.01). The magnitude of dilation differed as well. The z value of the sinuses of Valsalva was significantly higher in patients with R/L fusion (R/L, 2.03 versus R/N, 1.2; p = 0.003), whereas the z values of the ascending aorta and sinotubular junction were similar between the groups. Patients with R/N fusion were more likely to have aortic stenosis, and within the R/N group, patients with aortic insufficiency had a greater degree of ascending aorta dilation (p = 0.04). CONCLUSIONS: Our study suggests that in young patients with bicuspid aortic valves and aortic dilation, aortic valve morphology may be associated with the patterns of aortic dilation and valve dysfunction. Patients with R/N fusion were more likely to have ascending aorta dilation, whereas patients with R/L fusion were more likely to have dilation of the aortic root. In addition, patients with R/N fusion presented at a younger age and were more likely to have aortic stenosis. Recognition of these differences may eventually be helpful for patient counseling and the planning of follow-up.

Does the Homograft for RVOT Reconstruction in Ross: Patients Fare Better than for Non-Ross Patients? A Single-Center Experience.

BACKGROUND AND AIM OF THE STUDY: In patients undergoing the Ross procedure, the right ventricular outflow tract (RVOT) conduit is inserted in an orthotopic position rather than in the more heterotopic position used in the repair of complex congenital RVOT obstruction. The study aim was to compare the authors' institutional mid-term experience of large-sized homografts (>19 mm) in patients with Ross and non-Ross RVOT reconstructions. METHODS: The outcome was reviewed of all homografts implanted for Ross (n = 72) or non-Ross (n = 64) RVOT reconstruction at a single center between 1993 and 2012. Echocardiographic data were reviewed to evaluate valve performance. Homograft dysfunction was defined as RVOT obstruction with peak echo-Doppler gradient >40 mmHg and/or grade >III/IV conduit valve regurgitation. Homograft failure was defined as the need for conduit replacement or catheter or surgical reintervention. RESULTS: The age, body weight, conduit diameter and previous surgery were significantly higher in patients with Ross compared to the non-Ross group (p = 0.002, 0.003 and <0.001, respectively). The mean follow up duration was similar in both groups. There were 35 re-interventions (Ross, n = 17; non-Ross, n = 18). The data acquired showed actuarial survival, freedom from conduit dysfunction and conduit failure to be similar in both cohorts. Freedom from any type of reoperation was worse for the Ross group (58%) than for the non-Ross group (72%) (p = 0.05). CONCLUSION: During the first 15 years after Ross or non-Ross pulmonary homograft implantation, the survival rate, freedom from failure and dysfunction, and RVOT gradient were statistically similar. Freedom from any type of reoperation was significantly higher in the non-Ross group, however.

Outcomes of tricuspid valve repair in children with hypoplastic left heart syndrome.

OBJECTIVES: Tricuspid valve regurgitation (TR) is a common finding in children with hypoplastic left heart syndrome (HLHS) undergoing staged surgical reconstruction and can result from either abnormal valve morphology or incomplete leaflet coaptation due to annular dilatation. The purpose of this study was to determine the incidence of severe TR and to evaluate the effect of surgically treated tricuspid valve (TV) disease on overall survival. METHODS: Between December 1988 and December 2012, 86 patients with HLHS underwent a Norwood procedure (mean age/weight, 11.1 days/3.5 kg). Thirty-five percent had associated congenital cardiac, structural, and genetic anomalies. Subsequently, 65 patients underwent a bidirectional Glenn procedure or a hemi-Fontan (stage II) and 42 patients a modified Fontan procedure (stage III). The mean follow-up was 6.6 years. All patients were evaluated preoperatively and postoperatively by Doppler echocardiography to determine the degree of TR. RESULTS: At the time of discharge following the Norwood procedure, 64% (n = 47) of the patients had none/trivial, 32% (n = 24) had mild, 3% had moderate (n = 2), and 1% (n = 1) had severe TR on their post-Norwood Doppler echocardiograms. Among 74 Norwood survivors, 11 children (15%) with severe TR underwent TV repair at a median interval after the Norwood procedure of nine months (range, 2-70). There were one surgical and one late death, giving an overall mortality of 18%. The overall survival rate between TR and non-TR repair groups was not significantly different (p = 0.18). Four patients (36%) underwent reoperation for persistent TR. CONCLUSIONS: Severe TR as a risk factor for mortality in children undergoing palliative procedures for HLHS can be diminished by successful TV procedures. Survival at intermediate follow-up of patients with successful TV procedures that eliminate severe TR and patients without a history of severe TR are similar. Further follow-up is required to determine the impact of surgically treated TR on long-term survival and the durability of surgical techniques.

Failed autograft after the ross procedure in children: management and outcome.

BACKGROUND: Autograft dilatation (AD) and aortic insufficiency (AI) after the Ross procedure are the most common causes of late autograft failure. The purpose of this study was to examine the results of valve-sparing root replacement (modified David) and composite root replacement. METHODS: We performed a retrospective review of all children (n=78) undergoing a Ross procedure at our Center from 1993 to 2011. RESULTS: Median follow-up was 10 years (1to 18 years). Freedom from autograft reoperation was 94% at 5 years, and 65% at 15 years. Freedom from greater than 2+ autograft AI was 93% at 5 years and 76% at 15 years. Autograft reoperation was necessary in 22 patients, at a median interval of 8.7 years after the original procedure. Indications for reoperation were AI with autograft dilatation in 15 patients, AI without dilatation in 2 patients, and AD without AI in 5 patients. Surgical procedures used at reoperation included valve-sparing root replacement in 14 patients, root replacement either mechanical or biologic valved conduit in 6 patients, and valve replacement in 2 patients. At a mean follow-up of 5.8 years after reoperation, 4 patients from the valve-sparing group underwent second reoperation (valve replacement). Freedom from second autograft reoperation was 71% for patients after a valve sparing procedure and 100% for patients after an aortic valve or root replacement (Bentall procedure) at 5 years. CONCLUSIONS: Autograft valve-sparing root replacement and composite aortic root replacement are effective treatments for aortic root dilation and AI after the Ross procedure. The potential of late autograft insufficiency after valve-sparing root replacement warrants annual follow-up.

Outcomes of the modified norwood procedure: hypoplastic left heart syndrome versus other single-ventricle malformations.

Recent studies have suggested that survival after the modified Norwood procedure is influenced by anatomy and is worse for patients with hypoplastic left heart syndrome (HLHS) than for patients with other forms of functional single ventricle. This study aimed to compare the outcomes of the modified Norwood procedure for these two groups at a single center. A retrospective chart review compared modified Norwood procedure outcomes between children with HLHS (n = 40) and children with other single-ventricle malformations (n = 19) from January 2002 to August 2012. The HLHS patients had a lower mean age (10.0 ± 13.2 days) at the time of operation than the non-HLHS patients (16.5 ± 18.5 days). The difference was not significant. The number of patients with a Sano modification was significantly higher in the HLHS group (HLHS 85 % vs non-HLHS 32 %; p < 0.001). The follow-up data did not differ between the groups (HLHS 3.6 ± 3.2 years vs non-HLHS 4.8 ± 3.3 years, nonsignificant difference). The overall operative survival was 85 %: 83 % for the patients with HLHS and 89 % for the patients with non-HLHS (nonsignificant difference). The Kaplan-Meier transplant-free survival estimate at 10 years was 73 % and did not differ between the HLHS patients (67 %) and the non-HLHS patients (84 %, nonsignificant difference). The timing of stages 2 and 3 palliation (bidirectional Glenn and external conduit Fontan) did not differ significantly (HLHS, 7.0 ± 2.8 months and 3.0 ± 0.5 years vs non-HLHS 6.1 ± 1.7 months and 2.8 ± 0.8 years). The two groups were similar with respect to the need for post-Norwood extracorporeal membrane oxygenation support, aortic arch reinterventions, atrioventricular valve repair, pulmonary artery reconstruction, pacemaker implantation, and progression to bidirectional Glenn and Fontan completion. The modified Norwood reconstruction provides good palliation for HLHS as well as other forms of functional single-ventricle anatomy. Survival, postoperative morbidity, and progression to Glenn and Fontan are not significantly different.

Medication adsorption into contemporary extracorporeal membrane oxygenator circuits.

OBJECTIVE: This study was conducted to evaluate the amount of medication adsorbed into extracorporeal membrane oxygenation (ECMO) circuits with a polymethylpentane membrane oxygenator and heparin-coated polyvinyl chloride tubing. METHODS: An ECMO circuit with the aforementioned components was set up ex vivo and primed with expired blood. Midazolam, lorazepam, morphine, and fentanyl were administered to the circuit. Fifteen minutes after medication administration, 60 mL of blood were removed and stored in a 60-mL syringe to serve as a control. Medication levels were drawn from the ECMO circuit (test) and control syringe (control) 15 minutes, 24 hours, and 48 hours after the medications were administered. ECMO circuit medication levels were compared to their corresponding syringe control medication levels. Descriptive statistics were used to determine the percentage of medication remaining in the blood and compare it to the control value. RESULTS: Except for morphine, there was a large decline in medication levels over the 48-hour period. Compared to control values, 17.2% of midazolam, 41.3% of lorazepam, 32.6% of fentanyl, and 102% of morphine remained in the ECMO circuit. CONCLUSION: Despite the use of newer components in ECMO circuits, a large quantity of medication is adsorbed into the ECMO circuit. Midazolam, lorazepam, and fentanyl all showed reductions in medication levels greater than 50%. Morphine may have advantages for patients on ECMO, as its concentration does not appear to be affected.

Outcomes of double inlet left ventricle and similar morphologies: a single center comparison of initial pulmonary artery banding versus a norwood-type reconstruction.

OBJECTIVE: Patients with double inlet left ventricle (DILV)/transposition and similar morphologies have their systemic outflow traverse a bulboventricular foramen (BVF), which has a propensity to narrow over time. The aim of this study is to evaluate the outcomes of initial pulmonary artery banding (PAB) compared with the Norwood-type reconstruction in neonates. METHODS: A retrospective study of children with DILV and similar morphologies presenting between 1982 and 2012. The outcomes of initial PAB (n=17) are compared with a Norwood-type reconstruction (n=20). The two groups were similar with respect to age, gender, weight, noncardiac syndromes, and Fontan completion. Mean follow-up was longer in PAB patients (13.3 ± 9.8 years) versus Norwood (4.5 ± 3.0 years, p=0.001). RESULTS: Survival was 75% at eight years in the Norwood group versus 71% in the PAB group (p=0.76). Mortality in the Norwood group was higher before 2002 (p=0.06). The age of patients who underwent a bidirectional Glenn shunt was significantly higher for PAB group (PAB, 9.1 ± 1.4 months vs. Norwood, 6.1 ± 1.6 months; p<0.001). Freedom from any type of reintervention (systemic outflow obstruction or coarctation) was similar (Norwood, 83% vs. PAB, 71%; p=0.62). Freedom from heart block with a pacemaker insertion was significantly better for Norwood patients (Norwood, 89% vs. PAB, 41%; p=0.001). CONCLUSIONS: The Norwood-type reconstruction provides good palliation in this subgroup of patients and avoids the need for subsequent intracardiac operations, maintaining an unobstructed systemic outflow tract and avoiding the risk of heart block. Survival does not differ depending on the type of procedure. Patients with PAB show comparable satisfactory early and long-term results, with an increasing reoperation risk and heart block remaining a major concern.

Outcomes of pericardial bovine xenografts for right ventricular outflow tract reconstruction in children and young adults.

BACKGROUND AND AIM OF THE STUDY: A variety of valve substitutes has been used for right ventricular outflow tract (RVOT) reconstruction in children and young adults following previous RVOT surgery that has led to significant pulmonary insufficiency and/or stenosis. Herein, the authors' experience with pulmonary valve replacement (PVR) using a stented bovine pericardial xenograft late after previous RVOT surgery was reviewed. METHODS: Between 2000 and 2011, a total of 49 patients (mean age 22.4 +/- 12.3 years; range: 5-50 years) underwent PVR using stented bovine pericardial xenografts. All patients had prior RVOT reconstruction; these patients averaged two prior operations (range: 1-4) for the following diagnoses: tetralogy of Fallot (n = 28), pulmonary atresia (n = 6), pulmonary stenosis (n = 6), transposition of the great arteries (n = 3), truncus arteriosus (n = 1), and others (n = 5). Of these patients, 24 (49%) underwent additional procedures at the time of pulmonary valve insertion. RESULTS: There was no early death, but six late deaths. The overall survival rate was 88% at 10 years. All surviving patients were well at a mean follow up of 4.0 +/- 2.3 years (range: 6 months to 10 years). Echocardiography showed trivial or no pulmonary insufficiency in 22 patients (56%). The calculated mean peak systolic RVOT gradient at the last follow up by echocardiography was 22.7 +/- 6.6 mmHg. Freedom from RVOT reintervention and xenograft explantation was 94% and 98% at 10 years, respectively. CONCLUSION: The stented bovine pericardial xenografts demonstrated excellent intermediate-term results for repeat RVOT reconstruction. The hemodynamic characteristics of this valve are comparable to those of allografts, and the xenograft represents is an attractive alternative given the limited availability of allografts. The stented bovine pericardial xenograft remains an ideal valve choice for teenagers and young adults with congenital abnormalities of the RVOT, especially for redo as a second or third choice.

The Ross-Konno is a high-risk procedure when compared with the Ross operation in children.

BACKGROUND: For children who require aortic valve replacement, the pulmonary autograft (Ross procedure) may be the ideal substitute. However, performing a modified Konno procedure at the time of autograft implantation (Ross-Konno) may be associated with significant morbidity and mortality. A retrospective study was undertaken to compare the outcomes of Ross-Konno (RK) and the Ross (R) procedures including the need for reinterventions and long-term survival. METHODS: Between 1993 and 2011, 78 children (mean age, 11.1 ± 5.6 years; range, 1 week to 18 years) underwent the Ross procedure. Modified Konno-type enlargement of the left ventricular outflow tract was performed in 18 of those patients. RESULTS: There was no statistically significant difference between the groups with respect to pathologic process, sex, concomitant procedures, and aortic gradient. Our data demonstrate that mean age (R, 12.9 years versus RK, 5.3 years; p < 0.001), mean size of allograft (R, 23.3 mm versus RK, 20.1 mm; p < 0.001), previous surgery (R, 51% versus RK, 83%; p = 0.05), and postoperative morbidity (R, 3% versus RK, 28%; p = 0.003) were significantly different between the groups. There were 3 hospital deaths (all RK with mitral valve anomalies). Actuarial survival at 10 years was significantly better for Ross patients than Ross-Konno (R, 96% versus RK, 72%; p = 0.001). Freedom from autograft, right ventricular outflow tract obstruction, and cumulative reoperations at 10 years were not significantly different between groups. CONCLUSIONS: The risk of death and postoperative complications after the Ross-Konno procedure is higher than for the Ross procedure. Preoperative complexity (including mitral valve anomalies) is associated with significantly higher morbidity and mortality. Autograft insufficiency and right ventricular outflow tract obstruction are common postoperative complications, requiring reoperation in one quarter of patients, but these were not significantly different between the groups.

Autograft or allograft aortic root replacement in children and young adults with aortic valve disease: a single-center comparison.

BACKGROUND: We analyzed the outcome of children and young adults (younger than 40 years) with aortic valve disease who underwent allograft or autograft aortic root replacement (ARR) in our institution and evaluated whether there is a preference for either valve substitute. METHODS: One-hundred fifty patients younger than 40 years underwent ARR between January 1990 and July 2011. Forty-four patients, aged 18.8 ± 12.4 years, had ARR with allograft conduit (allograft group), whereas 106 patients, aged 17.9 ± 11 years (p = 0.63), had a Ross ARR during the same period of time (autograft group). Echocardiographic data were reviewed to evaluate valve performance. The 2 groups were similar with respect to age, gender, etiology, and previous and concomitant procedures. RESULTS: Operative deaths were 3 in the autograft group. There were 6 late deaths in the autograft group and 5 in the allograft group. Survival was 92% and 84% at 5 and 15 years, respectively, in the allograft group versus 93% and 91% in the autograft group (p = 0.42). Freedom from any type of reintervention and from reoperation on aortic valve were similar (autograft, 64% and 72% versus allograft, 66% and 66%; p = not significant) at 15 years. Freedom from explantation were significantly better for Ross patients (autograft, 82% versus allograft, 66%; p = 0.05). CONCLUSIONS: Aortic valve replacement with either the autograft or allograft provides good clinical results in children and young adults during an intermediate duration of observation. Survival early after ARR does not differ depending on the type of prosthesis. In patients with aortic valve disease, autograft and allograft ARR show comparable satisfactory early and long-term results, with the increasing reoperation risk in the second decade after operation remaining a major concern.

Decellularized versus standard cryopreserved valve allografts for right ventricular outflow tract reconstruction: a single-institution comparison.

BACKGROUND: Standard cryopreserved valved allografts (SCAs) are recognized as the benchmark for reconstruction of the right ventricular outflow tract (RVOT). However, SCAs frequently demonstrate early valve deterioration and elicit an immune response. Decellularized cryopreserved valve allografts (SynerGraft, SG) are less immunogenetic and may be more durable. This study analyzed our results of RVOT reconstruction using SGs and compared it with the SCAs used during the same period. METHODS: We reviewed the outcome of all allografts (SG and SCA) that were implanted for RVOT reconstruction at a single center from 2000 to 2005. Echocardiographic data were reviewed to evaluate valve performance. Conduit failure is defined as the need for conduit replacement or reintervention in either the catheterization laboratory or operating room. Conduit dysfunction is defined as RVOT obstruction with peak echocardiographic Doppler gradient greater than 40 mm Hg and/or grade III/IV or greater conduit valve regurgitation. Data were compared using the Wilcoxon rank sum and Fisher's exact test. RESULTS: From January 2000 to April 2005, 100 patients (mean age 18.6 ± 16.8 years) received SG (n = 39) or SCA (n = 61) conduits. The 2 retrospective nonrandomized cohorts were similar with respect to age, gender, weight, conduit indication, bypass and crossclamp time, and conduit size. Follow-up time was not significant between the 2 groups (SG, 5.7 ± 2.5 years vs SCA, 5.8 ± 2.8 years; P = .83). Early and late mortality were similar (SG, 13%; SCA, 10%; P = .75). No death was graft related. Freedom from dysfunction was superior with SG (SG, 74%, vs SCA, 52%; P = .05). Freedom from failure was also better in patients with SG (SG, 87%, vs SCA, 68%; P = .05). Freedom from explantation and more than moderate pulmonary insufficiency were significantly better for SG patients (SG, 92% and 90%, vs SCA, 78% and 68%; P = .02). CONCLUSIONS: This study suggests that the midterm performance of SGs may be superior to that of SCAs. Decellularization of the cryopreserved allografts may provide a more durable option for patients who need RVOT reconstruction. Further long-term follow-up is needed to see whether this decellularization process improves long-term allograft durability.

Pulse oximeter accuracy and precision affected by sensor location in cyanotic children.

OBJECTIVE: Children's digits are often too small for proper attachment of oximeter sensors, necessitating sensor placement on the sole of the foot or palm of the hand. No study has determined what effect these sensor locations have on the accuracy and precision of this technology. The objective of this study was to assess the effect of sensor location on pulse oximeter accuracy (i.e., bias) and precision in critically ill children. DESIGN: Prospective, observational study with consecutive sampling. SETTING: Tertiary care, pediatric intensive care unit. PATIENTS: Fifty critically ill children, newborn to 2 yrs of age, with an indwelling arterial catheter. Forty-seven of 50 (94%) patients were postcardiac surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Co-oximeter-measured arterial oxygen saturation (Sao2) was compared with simultaneously obtained pulse oximetry saturations (Spo2). A total of 98 measurements were obtained, 48 measurements in the upper extremities (finger and palm) and 50 measurements in the lower extremities (toe and sole). The median Sao2 was 92% (66% to 100%). There was a significant difference in bias (i.e., average Spo2 - Sao2) and precision (+/-1 sd) when the sole and toe were compared (sole, 2.9 +/- 3.9 vs. toe, 1.6 +/- 2.2, p = .02) but no significant difference in bias and precision between the palm and the finger (palm, 1.4 +/- 3.2 vs. finger, 1.2 +/- 2.3, p = .99). There was a significant difference in bias +/- precision when the Sao2 was <90% compared with when Sao2 was >or=90% in the sole (6.0 +/- 5.7 vs. 1.8 +/- 2.1, p = .002) and palm (4.5 +/- 4.5 vs. 0.7 +/- 2.4, p = .006) but no significant difference in the finger (1.8 +/- 3.8 vs. 1.1 +/- 1.8, p = .95) or toe (1.9 +/- 2.9 vs. 1.6 +/- 1.9, p = .65). CONCLUSIONS: The Philips M1020A pulse oximeter and Nellcor MAX-N sensors were less accurate and precise when used on the sole of the foot or palm of the hand of a child with an Sao2 <90%.

Are there benefits to a fresh whole blood vs. packed red blood cell cardiopulmonary bypass prime on outcomes in neonatal and pediatric cardiac surgery?

Techniques for pediatric cardiac surgery requiring cardiopulmonary bypass (CPB) have significantly improved over the years. The use of fresh whole blood (FWB) and pre-bypass ultrafiltration (PBUF) has been suggested as means for improving perioperative and postoperative outcomes. It is the intent of this study to show that fresh whole blood along with PBUF will result in balanced CPB prime that can offer a reduction in blood product exposures and blood loss along with improving several measured postoperative outcomes. After institutional review board approval, a retrospective review was conducted on 100 patients to analyze the benefits of FWB and PBUF on outcomes in neonatal and pediatric cardiac surgery. Data analysis included preoperative and CPB data, perioperative inotrope and blood product exposure, and postoperative blood loss and blood product exposure measured for up to a 12-hour period in the intensive care unit (ICU). The three groups compared were FWB prime vs. packed red blood cell (PRBC) prime, < 5 kg FWB prime vs. < 5 kg PRBC prime, and 5+ kg FWB prime and 5+ kg PRBC prime. Cumulative blood product exposures for the FWB prime group found 62% received one blood exposure for the operative and postoperative period (p < .0001). The majority of patients who received a PRBC prime (64%) received three or more cumulative exposures (p < .0003). The < 5 kg FWB group also received significantly less cumulative blood exposure, with 64% receiving just one exposure. Comparatively, 85% of the < 5 kg PRBC patients received three or more blood product exposures perioperatively and postoperatively (p < .0001). Perioperative inotrope and postoperative blood loss did not differ among the groups. Outcomes for intraoperative death, intraoperative extubation, delayed sternal closure, and mediastinal reexploration were also not statistically different. The results of this study found that FWB leads to significantly less blood exposure, specifically in the < 5-kg population. Finally, the use of PBUF is an effective method for achieving a balanced, physiologic prime. Future research would be helpful in determining which specific patient populations would receive the greatest benefit from FWB and PBUF.

Atrioventricular septal defects: effect of bridging leaflet division on early valve function.

BACKGROUND: Bridging leaflet division may facilitate repair of atrioventricular septal defects (AVSD). However, the consequences of bridging leaflet division on early valve function and mortality are not well defined. METHODS: Records of children undergoing AVSD repair between January 1995 and January 2002 were reviewed. Multivariable analysis defined risk factors for moderate or greater atrioventricular valve regurgitation (AVVR) and death/reoperation within 1 year of repair. RESULTS: A total of 209 children (median age 5 months, median weight 5 kg) had defects whose repair included the possibility of bridging leaflet division. Bridging leaflets divided were both (n = 119, 58%), one (n = 30, 15%), or none (n = 55, 27%). Freedom from AVVR (moderate or greater) is 84%, 80%, and 78% at 1, 6, and 12 months. Risk factors include technical factors: number of bridging leaflets divided, longer cross-clamp time, and right-sided annuloplasty. Other risk factors include preoperative AVVR (moderate or greater), double-orifice or parachute left AV valve, and younger age. Freedom from death/reoperation for AVVR is 96%, 92%, and 90% at 1, 6, and 12 months. Risk factors are preoperative AVVR (moderate or greater) and parachute left AV valve. Findings at reoperation (n = 15, 7.2%) were cleft dehiscence or tear along cleft closure (n = 10), dehiscence of divided leaflet from septation patch (n = 1), or other (n = 4). Operative mortality (n = 6, 2.9%) included failed reoperations for AVVR (n = 4), dehiscence of divided leaflet from septation patch (n = 1), and sepsis (n = 1). CONCLUSIONS: Division of bridging leaflets is a risk factor for AVVR (moderate or greater) during the first year after repair. Preservation of bridging leaflet integrity may improve valve competency, decrease the need for future reoperation, and eliminate some causes of operative mortality.