Feeding Intolerance After Pediatric Cardiac Surgery Is Related To Dysbiosis, Barrier Dysfunction And Reduced Short-Chain Fatty Acids.

BACKGROUND: Congenital heart disease (CHD) is the most common birth defect, occurring in roughly 40,000 US births annually. Malnutrition and feeding intolerance (FI) in CHD ranges from 30-42% and is associated with longer hospitalization and increased mortality. Cardiopulmonary bypass (CPB) required for surgical repair of CHD induces a systemic inflammatory response worsening intestinal dysbiosis and inducing intestinal epithelial barrier dysfunction (EBD), possibly contributing to post-operative FI. OBJECTIVE: To determine the relationship of post-operative FI with intestinal Microbiome, short-chain fatty acids (SCFA), and EBD in pediatric CHD after cardiac surgery. METHODS: Prospective study of patients aged 0-15 years undergoing cardiac surgery with CPB. Samples were collected pre-operatively and post-operatively to evaluate the gut microbiome, plasma EBD markers, short-chain fatty acids (SCFA), and plasma cytokines. Clinical data was collected to calculate a FI score and evaluate patient status post-operatively. RESULTS: We enrolled 26 CPB patients and identified FI (n=13). Patients with FI had unique microbial shifts with reduced SCFA-producing organisms, Rothia, Clostridium innocuum, and Intestinimonas. Patients who developed FI had associated elevations in plasma EBD markers, claudin-2 (p<0.05), claudin-3 (p<0.01), and fatty acid binding protein (p<0.01). Patients with FI had reduced plasma and stool SCFAs. Mediation analysis showed the microbiome functional shift was associated with reductions in stool butyric and propionic acid in patients with FI. CONCLUSION: We provide novel evidence that intestinal dysbiosis, markers of EBD, and SCFA depletion are associated with FI. This data will help towards identifying mechanism and therapeutics to improve clinical outcomes following pediatric cardiac surgery.

Predictors of Valve Failure Following Surgical Atrioventricular Valve Replacement with a Melody Valve in Infants and Children.

Options for atrioventricular (AV) valve replacement in small pediatric patients are very limited. The Melody valve has shown reasonable short-term outcomes. This study was aimed at identifying predictors of valve failure following AV valve replacement with a Melody valve at a single-center. 26 patients underwent 37 AV valve replacements with 31/37 (84%) of valves placed in the systemic AV valve position. Median age at procedure was 17 months (IQR 4-33) and weight was 8.5 kg (IQR 6.25-12.85). Median balloon size for valve implant was 20 mm (IQR 18-22). Repeat intervention occurred in 21 cases (57%) with repeat surgery in all but one. Median freedom from re-intervention was 31 months; 19% were free from re-intervention at 60 months. Age < 12 months weight < 10 kg and BSA < 0.4 m2 were all significant risk factors for early valve failure (p = 0.003, p 0.017, p 0.025, respectively). Valve longevity was greatest with balloon inflation to diameter 1.20-1.35 times the patient's expected annular diameter (Z0), relative to both smaller or larger balloons (p = 0.038). In patients less than 12 months of age, patients with single ventricle physiology had an increased risk of early valve failure (p = 0.004).

Postoperative Breath-Holding Spells Requiring Cardiopulmonary Resuscitation After Cardiopulmonary Bypass.

Breath-holding spells are common in childhood and can be associated with bradycardia and pulselessness. This report details severe breath-holding spells complicating postoperative management after atrial septal defect closure. The patient required cardiopulmonary resuscitation despite the use of a temporary pacemaker to prevent bradycardia. After multiple episodes of chest compressions, the decision was made to not intervene immediately to pulselessness and the patient was able to recover without further intervention.

Post-heart transplant survival is inferior at low-volume centers across all risk strata.

BACKGROUND: Previous studies have demonstrated a relationship between increasing center volume and cardiac transplant outcomes. The purpose of this study was to confirm a relationship between post-heart transplant outcomes and center experience and to determine whether this relationship persists among low- and high-risk heart transplant recipient-donor pairs. METHODS AND RESULTS: The United Network for Organ Sharing (UNOS) provided deidentified patient-level data. Analysis included 8029 heart transplant recipients aged ≥18 years and transplanted between January 1, 2001 and December 31, 2006 with follow-up available through February 3, 2009. The primary outcome was observed 1-year posttransplant graft survival. Multivariable logistic regression was used to calculate expected 1-year survival for recipients. Threshold analysis identified 3 discrete risk groups of transplant recipients: high-risk, moderate-risk, and low-risk. Three discrete risk strata for center volume: low (<10.5 recipients/yr), intermediate (10.5 to 47 recipients/yr), and high (>47 recipients/yr) were also identified. χ(2) test was used to compare 1-year survival at low- and intermediate- with high-volume centers. In multivariable logistic regression analysis, annual center volume was significantly associated with posttransplant graft survival at 1 year (odds ratio [OR]=0.995, 0.992 to 0.999; P=0.010) and primary graft failure (OR=0.985, 0.972 to 0.997; P=0.015), but not stroke (OR=0.996, 0.990 to 1.003; P=0.295), infection (OR=1.001, 0.998 to 1.003; P=0.613), or dialysis (OR=1.001, 0.997 to 1.005; P=0.522). Log-rank test demonstrated significant difference in survival between volume groups with respect to high-risk (P=0.0032) and low-risk (P=0.00415), but not moderate-risk (P=0.128) patients. CONCLUSIONS: A direct relationship existed between increasing center volume and improved graft survival. Across all recipient-donor pair risk strata, posttransplant graft survival at 1 year was significantly lower at low-volume centers. The volume-outcomes relationship was strongest in the highest-risk recipient-donor category.

Williams Syndrome and Neonatal Cardiac Surgery for Congenital Single Ventricle.

Williams syndrome (WS) is an arteriopathic derangement associated with supravalvular aortic stenosis and branch pulmonary stenosis. We describe double-outlet right ventricle with mitral atresia and aortic arch hypoplasia in an infant with WS. This case demonstrates the difficulty in managing patients with WS with complex cardiac defects. To our knowledge, this is the first reported single-ventricle physiology in a patient with WS. (Level of Difficulty: Advanced.).

Outcomes related to immediate extubation after stage 1 Norwood palliation for hypoplastic left heart syndrome.

OBJECTIVE: Immediate extubation may have outcome benefits when judiciously instituted after neonatal congenital cardiac surgery. We sought to evaluate the outcomes of immediate extubation specifically in neonates undergoing stage 1 Norwood palliation of hypoplastic left heart syndrome. METHODS: Consecutive neonates undergoing stage 1 Norwood (January 2010 to December 2016) for hypoplastic left heart syndrome were retrospectively studied. Immediate extubation was defined as successful extubation before termination of anesthetic care. Preoperative and intraoperative variables were compared between immediate extubation and nonimmediate extubation groups, and bivariate analyses and descriptive methods were used to express the association of outcome variables with immediate extubation. Data were expressed as number and percent for categoric variables, and median and interquartile range for continuous variables. RESULTS: Of 23 patients who underwent stage 1 palliation, 5 had immediate extubation (22%). There were no differences in preoperative or intraoperative factors between patients who did and did not undergo immediate extubation. There were no deaths in the immediate extubation group. In the nonimmediate extubation group, 3 patients died before hospital discharge. One patient who had immediate extubation and 4 patients among those who did not have immediate extubation had to be reintubated in the 96 hours that followed extubation (P = 1). Intensive care unit length of stay was 8 (3-17) and 8 (5-18) (days) for the immediate extubation group and nonimmediate extubation groups, respectively (P = .71). CONCLUSIONS: Immediate extubation strategy was safely accomplished in one-fifth of this cohort of hypoplastic left heart syndrome. A larger cohort may delineate the determinants of immediate extubation and its benefits in infants undergoing stage 1 single ventricle palliation.

An Analysis of Left Ventricular Retraining in Patients With Dextro- and Levo-Transposition of the Great Arteries.

BACKGROUND: Patients with dextro (D)-transposition of the great arteries (TGA) who have undergone a previous atrial switch and for some patients with levo (L)-TGA (ie, no ventricular septal defect or outflow tract obstruction), the left ventricle (LV) may require retraining before late arterial switch. The purpose of this study was to analyze the results of LV retraining for these two entities. METHODS: This was a retrospective review of 51 patients enrolled in an LV retraining program. There were 25 patients with D-TGA and 26 with L-TGA. The median age of the D-TGA patients was 15 years, and 22 of 25 were in New York Heart Association class III or IV. The median age of the L-TGA patients was 12 months, and 3 of 26 patients were in New York Heart Association class III or IV. RESULTS: LV retraining was successful in 13 of the 25 patients (52%) with D-TGA, and 10 these 13 patients (77%) underwent successful late arterial switch. Of the 26 patients with L-TGA, LV retraining was successful in 24 (92%), and a double-switch operation was successful in 19 of 19 (100%) who subsequently underwent that procedure. A mathematical formula based on the incremental gain in left-to-right ventricular pressure ratio correctly predicted the success or failure in 94% of the patients. CONCLUSIONS: The data demonstrate differences in the success of LV retraining and late arterial switch for D-TGA and L-TGA. We would propose that the LV retraining ratio may be useful in objectively selecting patients eligible for late arterial switch.

Left Ventricular Retraining and Double Switch in Patients With Congenitally Corrected Transposition of the Great Arteries.

PURPOSE: Congenitally corrected transposition of the great arteries (CC-TGA) is a complex form of congenital heart defect with numerous anatomic subgroups. The majority of patients with CC-TGA are excellent candidates for a double-switch procedure. However, in the absence of an unrestrictive ventricular septal defect or subpulmonary stenosis, the left ventricle (LV) may undergo involution and require retraining prior to double switch. The purpose of this study was to review our experience with patients having CC-TGA who required LV retraining prior to a double-switch procedure. METHODS: This was a retrospective review of 24 patients with CC-TGA who were enrolled in an LV retraining program in preparation for a double-switch procedure. The median age at the time of enrollment for retraining was 11 months (range 1 month-24 years). The average left ventricle to right ventricle pressure ratio was 0.39 ± 0.07 prior to intervention. All 24 patients underwent placement of an initial pulmonary artery band (PAB) for LV retraining. RESULTS: Eighteen (75%) of the 24 patients underwent a double-switch procedure with no operative mortality. Of these 18 patients, 9 had a single PAB and 9 required a second band for retraining. Six patients have not undergone a double-switch procedure to date. Five patients are good candidates for a double switch and are 2 weeks, 3 weeks, 4 weeks, 8 months, and 35 months since their last PAB. One patient died from a noncardiac cause 26 months after PAB retightening. The 18 patients who underwent a double switch were followed for an average of 5 ± 1 years (range 0.1-10.3 years). There has been no late mortality, and only 2 patients required further reinterventions. CONCLUSION: The data demonstrate that LV retraining has been highly effective in this select group of patients with CC-TGA. The data also demonstrate that the results of the double-switch procedure have been excellent at midterm follow-up. These results suggest that LV retraining and double switch offer a reliable strategy option for patients with CC-TGA.

Surgical Technique for Repair of Peripheral Pulmonary Artery Stenosis and Other Complex Peripheral Reconstructions.

Surgical reconstruction of peripheral pulmonary artery stenosis is a technically challenging procedure due to the need to access all lobar and segmental branches. This paper describes our surgical approach that entails division of the main pulmonary and separation of the branch pulmonary arteries. This surgical approach can also be utilized for other complex peripheral pulmonary artery reconstructions.

Early Complete Atrioventricular Canal Repair Yields Outcomes Equivalent to Late Repair.

BACKGROUND: Repair of complete atrioventricular canal early in infancy has traditionally carried greater morbidity and mortality than repair performed later. However, an individualized anatomy-based repair may give young infants outcomes that are equivalent to older patients. METHODS: We retrospectively reviewed 139 patients who underwent complete atrioventricular canal repair from January 2005 to December 2012. An individualized approach was used: 2-patch repair was performed in 98 patients for large ventricular septal defects and a modified single-patch ("Australian technique") was used in 41 for "shallow" ventricular septal defects. RESULTS: The average age was 25.5 ± 3.9 weeks, 50% were boys, and 78% had trisomy 21. Mean follow-up was 5.1 ± 0.2 years, with 100% completeness of data. There were 3 in-hospital deaths (2.1%) and 1 late death (0.7%). A permanent pacemaker was required in 2 patients (1.4%). The rate for left atrioventricular valve reoperation was 8% at a mean of 211 ± 238 days after the original repair (range, 6 to 682 days). Compared with patients aged older than 3 months, the 39 patients (28%) who were younger than 3 months had similar perioperative courses and rate of reoperation. Compared with patients with an Australian repair, the 98 patients (71%) with a 2-patch repair were more likely to have trisomy 21 and had slightly increased cardiopulmonary bypass and cross-clamp times but similar outcomes. Multivariate analysis showed postoperative left atrioventricular valve regurgitation greater than 2 and left ventricular outflow tract obstruction were significant risk factors for reoperation on the left atrioventricular valve (both p < 0.05). CONCLUSIONS: Repair of complete atrioventricular canal using an individualized surgical approach yields reoperation and early mortality rates similar for younger infants compared with older infants, obviating the need to delay operation in symptomatic patients.

Use of bicaval dual-lumen catheter for adult venovenous extracorporeal membrane oxygenation.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) provides supplementary oxygenation and carbon dioxide removal for selected patients on mechanical ventilatory support. Venovenous ECMO is traditionally established by dual cannulation of the internal jugular and femoral veins. We report our institutional experience using single-site, dual-lumen cannula for venovenous ECMO as an alternative to the 2-catheter approach. This approach minimizes recirculation and avoids use of the femoral site, which confers potential advantages. METHODS: This is a retrospective review of a single institution's experience with a new bicaval dual lumen ECMO cannula. During a 19-month period, 27 consecutive patients were placed on ECMO using this catheter inserted through the right internal jugular vein. RESULTS: Single-site venovenous ECMO support was uneventfully initiated in 26 of the 27 patients (median age, 42 years; interquartile range, 31 to 58 years) and achieved full flows and adequate gas exchange. Median ventilator days before ECMO was 1 day (interquartile range, 0.25 to 3.5 days). The median duration of ECMO support was 9 days (interquartile range, 5.5 to 11.5 days). Decannulation was achieved in 70% of the patients and extubation in 59%. Two were bridged to lung transplantation and are still alive. The overall survival and hospital discharge rate was 56%. There was no device failure or in-cannula thrombosis. One superior vena cava injury occurred, and one cannula required repositioning. CONCLUSIONS: Single-site venovenous ECMO has advantages compared with traditional venovenous ECMO. Using image guidance, the cannula can reliably be used in prolonged venovenous ECMO cases.

Analysis of clamping versus cutting of T3 sympathetic nerve for severe palmar hyperhidrosis.

OBJECTIVES: Endoscopic thoracic sympathectomy can predictably eliminate the disabling symptoms of palmar hyperhidrosis. Debate has ensued over competing techniques, in particular, cutting versus clamping of the sympathetic chain. We subjectively assessed the sweat severity in different areas of the body and evaluated changes in the quality of life in patients undergoing either the cutting or clamping technique. METHODS: Patients examined between June 2003 and March 2007 were asked to quantify the severity of their symptoms before and after endoscopic thoracic sympathectomy. The interviews were conducted approximately 1 year after the procedure. Only the patients undergoing sympathectomy at the T3 level for a chief complaint of palmar hyperhidrosis were included in the analysis (n = 152). In 45% of these patients, clamping of the sympathetic chain was performed, and the remaining 55% had the chain cut. RESULTS: After surgery, no patients had continued excessive sweating of the hands. Of all the patients, 95% were satisfied with the results after the cutting procedure and 97% were satisfied after clamping. No difference was seen in any outcome between the patients undergoing clamping versus cutting of the sympathetic chain, including sweating on the hands, face, armpits, feet, trunk, and thighs or in the quality of life. CONCLUSIONS: We found high rates of success and patient satisfaction when T3 sympathectomy was performed for palmar hyperhidrosis, with no differences found between the cutting and clamping techniques.

High lung allocation score is associated with increased morbidity and mortality following transplantation.

BACKGROUND: The lung allocation score (LAS) was initiated in May 2005 to allocate lungs based on medical urgency and posttransplant survival. The purpose of this study was to determine if there is an association between an elevated LAS at the time of transplantation and increased postoperative morbidity and mortality. METHODS: The United Network for Organ Sharing provided de-identified patient-level data. Analysis included lung transplant recipients aged >or= 12 years who received transplants between April 5, 2006, and December 31, 2007 (n = 3,836). Recipients were stratified into three groups: LAS < 50 (n = 3,161, 83.87%), LAS 50 to 75 (n = 411, 10.9%), and LAS >or= 75 (n = 197, 5.23%), referred to as low LAS (LLAS), intermediate LAS (ILAS), and high LAS (HLAS), respectively. The primary outcome was posttransplant graft survival at 1 year. Secondary outcomes included length of stay and in-hospital complications. RESULTS: HLAS recipients had significantly worse actuarial survival at 90 days and 1 year compared with LLAS recipients. When transplant recipients were stratified by disease etiology, a trend of decreased survival with elevated LAS was observed across all major causes of lung transplant. HLAS recipients were more likely to require dialysis or to have infections compared with LLAS recipients (P < .001). In addition, length of stay was higher in the HLAS group when compared with the LLAS group (P < .001). CONCLUSIONS: HLAS is associated with decreased survival and increased complications during the transplant hospitalization. Whereas the LAS has improved organ allocation through decreased waiting list deaths and waiting list times, lower survival and higher morbidity among HLAS recipients suggests that continued review of LAS scoring is needed to ensure optimal long-term transplant survival.