Operative Repair of Aortopulmonary Window: A 25-Year Experience.

Background: Aortopulmonary window (APW) is a rare anomaly with variable morphology and associated cardiac anomalies. We evaluated impact of patient and operative factors on mid-term outcomes following APW repair. Methods: Twenty-nine patients underwent surgical APW repair at our institution from 1996 to 2022. Eight (28%) had simple APW, accompanied by only atrial septal defect or patent ductus arteriosus; 21 (72%) had complex APW with additional cardiovascular lesions, including nine with interrupted aortic arch. Median operative age was 19 days (range 2 days-1.5 years) via single-patch (n = 12, 41%), double-patch (n = 15, 52%), or ligation and division (n = 2, 7%). Results: The only mortality occurred in-hospital 1.4 years postoperatively following remote myocardial infarction. Factors associated with longer postoperative length of stay were complex APW (P = .003), genetic syndrome (P = .003), noncardiovascular comorbidities (P = .002), lower birth weight (P = .03), and lower operative weight (P = .03). Six patients (21%) with complex APW underwent unplanned cardiothoracic reintervention(s), including two with arch reintervention following arch advancement for interruption. Reintervention-free survival was similar for simple versus complex APW, operative age categories, and repair techniques. At median follow-up 5.5 years postoperatively, no patients had residual APW or persistent pulmonary hypertension, 1 (3%) had greater than mild ventricular dysfunction, and 25 (89% survivors) had NYHA class I functional status. Conclusions: Operative APW repair has excellent mid-term survival, durability, and functional status, regardless of operative age, cardiovascular comorbidities, or repair technique. Cardiac and noncardiac comorbidities may be associated with prolonged length of stay.

Temporary ventricular assist device support with a catheter-based axial pump: Changing the paradigm at a pediatric heart center.

OBJECTIVE: We report the largest pediatric single-center experience with an Impella (Abiomed Inc) catheter-based axial pump support. METHODS: We conducted a retrospective cohort study of all patients with acute decompensated heart failure or cardiogenic shock requiring catheter-based axial pump support between October 2014 and February 2022. The primary outcome per individual encounter (hospital admission) was defined as bridge-to-recovery, bridge-to-durable ventricular assist device support, bridge-to-cardiac transplantation, or death at 6 months after catheter-based axial pump explantation. Adverse events were defined according to the Pediatric Interagency Registry for Mechanical Circulatory Support criteria. RESULTS: Our final study cohort included 37 encounters with 43 catheter-based axial pump implantations. A single catheter-based axial pump device was used for support in 33 encounters (89%), with 2 catheter-based axial pump devices used in 3 (8%) separate encounters and 3 catheter-based axial pump devices used in 1 (3%) encounter. The median [range] age, weight, and body surface area at implantation were 16.8 [6.9-42.8] years, 61.1 [23.1-123.8] kg, and 1.7 [0.8-2.5] m2, respectively. The predominant causes of circulatory failure were graft failure/rejection in 16 patients (43%), followed by cardiomyopathy in 7 patients (19%), arrhythmia refractory to medical therapies in 6 patients (16%), myocarditis/endocarditis in 4 patients (11%), and heart failure due to congenital heart disease in 4 patients (11%). Competing outcomes analysis showed a positive outcome with bridge-to-recovery in 58%, bridge-to-durable VAD support in 14%, and bridge-to-cardiac transplantation in 14% at 6 months. Fourteen percent of encounters resulted in death at 6 months. CONCLUSIONS: We demonstrate that catheter-based axial pump support in children results in excellent 1- and 6-month survival with an acceptable adverse event profile.

Modified biatrial heart transplantation after bilateral bidirectional cavo-pulmonary shunts.

We describe a patient who underwent modified biatrial anastomosis heart transplantation after the bilateral Glenn procedure. We introduced a new surgical technique to use the native central pulmonary artery as systemic venous return, which was anastomosed to right atrium, and then, biatrial anastomosis was performed.

Shunt resistance is associated with clinically important outcomes after the Norwood operation.

Background: In single-ventricle physiology, focus on pulmonary vascular resistance neglects the resistance in the conduit supplying the pulmonary inflow. Methods: Conduit length and diameter, which can approximate conduit resistance, are available in the public dataset of Single Ventricle Reconstruction (SVR) trial. Conduit resistance was then calculated for SVR trial participants and the relationship with clinically important variables (death or transplant at 1 year, pulmonary artery size at second-stage palliation, pulmonary-to-systemic blood flow ratio, and supplemental oxygen requirement) was explored. To validate this calculated resistance, calculated resistance was compared with catheterization measurements at a single institution (not included in the SVR trial). Results: In the institutional dataset, calculated and measured resistances had an intraclass correlation of 0.78 for modified Blalock-Taussig shunts (MBTS). Within the SVR trial, transplant-free survivors had a lower MBTS resistance (median, 8.3 Woods Units [WU]. interquartile range [IQR], 6.5-11.1 WU) than patients who died or required transplantation (median, 13.0 WU; IQR, 9.4-16.6 WU, P = .0001). When we controlled for left pulmonary artery diameter after the Norwood procedure in the SVR trial, for each unit increase in MBTS resistance, the left pulmonary artery diameter at stage II decreased (-0.006 ± 0.002 cm, P = .005). When we controlled for pulmonary vascular resistance, greater MBTS resistance was associated with a decrease in log pulmonary-to-systemic blood flow ratio (-0.04 ± 0.015, P = .0048) in the SVR trial. Patients in the SVR trial requiring supplemental oxygen on admission for stage II palliation had greater MBTS resistance (median. 11.1 WU; IQR, 6.6-16.6 WU) than patients not requiring oxygen (median 8.3, WU; IQR, 6.5-11.1 WU, P = .015). Conclusions: Conduit resistance is associated with important clinical outcomes after Norwood; however, further studies are required to guide conduit resistance optimization.

Modified atrioventricular valve replacement in children.

One major challenge of atrioventricular valve replacement in children is the small size of the native valve annulus. In addition, in cases of atrioventricular septal defect, the atrioventricular node (AVN) shifts to a different location, making this condition difficult to treat. This report describes a technique that uses a trapezoid-shaped patch to separate the implanted valve suture-line from the AVN, which allows surgeons to implant larger valves while simultaneously preventing injury to the AVN.

Right Ventricle to Pulmonary Artery Conduit Size Is Associated with Conduit and Pulmonary Artery Reinterventions After Truncus Arteriosus Repair.

We studied conduit-related risk factors for mortality, conduit reintervention, conduit replacement, and pulmonary artery (PA) reinterventions after truncus repair. Patients who underwent truncus repair at our institution between 1995 and 2019 were studied. Cox proportional hazards modeling evaluated variables for association with mortality, time to conduit reintervention, time to conduit replacement, and time to PA reintervention. Truncus was repaired in 107 patients at median age of 17 days (IQR 9-45). Median follow-up time was 7 years. Aortic homografts were implanted in 57 (53%) patients, pulmonary homograft in 40 (37%), and bovine jugular conduit in 10 (9%). Median conduit size was 11 mm (IQR 10-12) and median conduit Z-score was 1.71 (IQR 1.08-2.34). At 5 years, there was 87% survival, 21% freedom from conduit reinterventions, 37% freedom from conduit replacements, and 55% freedom from PA reinterventions. Conduit size (HR 0.7, 95%CI 0.4-1.4, p=.41) and type (aortic homograft reference; bovine jugular vein graft HR 0.6, 95% CI 0.08-5.2, p=.69; pulmonary homograft HR 0.7, 95% CI 0.2-2.3, p=.58) were not associated with mortality. On multivariate analysis, the hazard for conduit reintervention, conduit replacement, and PA reintervention decreased with increasing conduit Z-score values of 1 to 2.5 (non-linear relationship, p<.01), with little additional reduction in hazard beyond this range. Implantation of a larger conduit within Z-score values of 1 and 2.5 is associated with a decreased hazard for conduit reintervention, conduit replacement, and PA reintervention after truncus repair. The type and size of the conduits did not impact mortality.

Heart Transplantation in a Case of Scimitar Syndrome.

We present a rare clinical scenario of a patient with tetralogy of Fallot, hypertrophic cardiomyopathy, and concomitant scimitar syndrome. We created a scimitar vein cuff from a recipient heart, performed its translocation, and subsequently performed heart transplantation. This ingenuity reduces the likelihood of scimitar vein obstruction.

Perioperative evaluation of neonatal aortic arch thrombosis.

Herein, we present a neonatal case of coarctation of the aorta, with aortic arch thrombus confirmed by echocardiography. We performed thrombus removal and aortic arch repair emergently. This critical condition necessitates quick preoperative evaluation with echocardiography. Moreover, postoperative evaluation using computed tomography is reasonable to assess an aortic arch configuration, and exclude the remnant thrombus.

Intrinsic Coronary Stenosis With Ventricular Dysfunction in Tetralogy of Fallot.

Intrinsic coronary anomalies in tetralogy of Fallot are rare manifestations that are difficult to diagnose, especially when accompanied by ventricular dysfunction in the postoperative period. We present a case of severe left ventricular dysfunction after repair of tetralogy of Fallot. Coronary angiography revealed intrinsic left main coronary stenosis. Therefore, we emergently performed patch augmentation of the left main coronary artery concomitantly with residual ventricular septal defect closure. While evaluating patients with tetralogy of Fallot, especially in the presence of ventricular dysfunction, intrinsic coronary anomalies should be kept in mind. Coronary angiography is effective in diagnosing coronary anomalies.

Smaller right pulmonary artery is associated with longer survival time without scimitar vein repair.

INTRODUCTION: The optimal management of scimitar syndrome remains incompletely defined. We (1) evaluated the impact of aortopulmonary collateral (APC) occlusion, (2) compared outcomes according to surgical approach for patients who underwent surgery, and (3) identified anatomic factors associated with longer survival time without scimitar vein repair. METHODS: We conducted a single center, retrospective study of 61 patients diagnosed with scimitar syndrome between 1995 and 2019. Right pulmonary artery to total pulmonary artery cross-sectional area (RPA:PA CSA) quantitatively assessed right pulmonary artery size. Anatomical features were analyzed for association with longer survival time without scimitar vein repair. RESULTS: Median follow-up time was 6 years (Q1-Q3, 2-12), with 96% 5-year survival. Twenty-three patients underwent APC occlusion, which significantly decreased symptoms of overcirculation (100%-46%; p = .001) and systolic pulmonary artery pressure (median, 34-29 mmHg; p = .004). Twenty-three patients underwent scimitar vein repair; 5-year freedom from scimitar vein stenosis was 90% among patients who underwent a reimplantation compared with 42% in patients with baffle repair (p = .1). Three patients underwent surgery before the first year of age, with lower 5-year freedom from scimitar vein stenosis (0% vs. 84%; p < .001). On multivariate analysis, a lower RPA:PA CSA was associated with longer survival time without scimitar vein repair (p = .003). CONCLUSIONS: APC occlusion improves the clinical status of young and hemodynamically unstable patients. Repair at an early age is associated with an increased risk of scimitar vein stenosis. Scimitar vein repair might be avoided in patients with a smaller right pulmonary artery.

Midterm outcomes of pulmonary artery sling repair with and without tracheoplasty.

OBJECTIVE: Review a single-centre experience with pulmonary artery sling repair and evaluate risk factors for re-intervention. METHODS: Patients with surgically repaired pulmonary artery sling at a single institution between 1996 and 2018 were retrospectively reviewed. A univariate Cox regression analysis was used to evaluate variables for association with freedom from re-intervention. RESULTS: Eighteen patients had pulmonary artery sling repair. At operation, median age and weight were 6.9 months (interquartile range 4.1-18.1) and 9.5 kg (interquartile range 6.5-14.5), respectively. A median hospital length of stay was 12 days (interquartile range 5.8-55.3). Twelve patients (67%) had complete tracheal rings, of whom six (50%) underwent tracheoplasty (five concurrently with pulmonary artery sling repair). Airway re-intervention was required in five (83%) of the six patients who underwent tracheoplasty. One patient had intraoperative diagnosis and repair of pulmonary artery sling during unrelated lesion repair and required tracheoplasty 24 days post-operatively. One patient died 55 days after pulmonary artery sling repair and tracheoplasty following multiple arrests and re-interventions. Median post-operative follow-up for surviving patients was 6.3 years (interquartile range 11 months-13 years), at which time freedom from re-intervention was 61%. When controlling for patient and tracheal size, initial tracheoplasty was associated with decreased freedom from re-intervention (hazard ratio 21.9, 95% confidence interval 1.7-284.3, p = 0.018). CONCLUSIONS: In patients with pulmonary artery sling, tracheoplasty is associated with decreased freedom from re-intervention. In select patients with pulmonary artery sling and complete tracheal rings, conservative management without tracheoplasty is feasible. Further study is necessary to delineate objective indications for tracheoplasty.

Surgical Techniques in Management of Supravalvular Aortic Stenosis in Children.

BACKGROUND: Multiple techniques exist for the repair of supravalvular aortic stenosis (SVAS), but given the lesion's rarity, analyses comparing the efficacy of each repair have been limited. METHODS: A retrospective review of all children at a single institution who underwent repair of SVAS from June 1995 to May 2019 was performed. Anatomic and physiologic measurements across time points were compared between 2 predominant surgical techniques. Time-to-event outcomes were compared using the log-rank test. RESULTS: SVAS was repaired in 89 patients, by using a single-patch in 31 (35%) and the Doty repair in 58 (65%). Median age at operation was 2.5 years (interquartile range [IQR], 1.0 to 6.8 years), with median follow-up of 5.8 years (IQR, 1.8 to 10.7 years). Reoperation was required in 8 (9%) patients at a median of 1.5 years postoperatively (IQR, 0.3 to 4.8 years). There was 1 death after multiple reinterventions. The change from the preoperative to the postoperative sinotubular junction z-score was greater for patients after Doty repair (median change +2.5; IQR, 1.5, 4.1) than for patients after single-patch repair (median change +0.8; IQR, -0.1, 2.1; P = .001). Freedom from reoperation was longer for patients after Doty repair than after the single-patch technique (P = .008). CONCLUSIONS: The Doty repair provides longer freedom from reoperation after supravalvular aortic stenosis repair compared with a single-patch technique, likely through a greater increase in the sinotubular junction at the time of initial operation.

Younger Age at Operation Is Associated With Reinterventions After the Warden Procedure.

BACKGROUND: Multiple techniques are available for repair of supracardiac partial anomalous pulmonary venous return (PAPVR); however, most series fail to compare the techniques in contemporary cohorts. This study aimed to describe outcomes of the Warden procedure with a single-patch repair cohort to serve as a control. METHODS: A retrospective cohort analysis of all patients at a single institution (Texas Children's Hospital, Houston, TX) included patients undergoing either the Warden procedure or single-patch repair from 1996 to 2019 for PAPVR. Reintervention was defined as any catheter or surgical procedure on the superior vena cava (SVC) or pulmonary veins. Subgroup analysis was performed within the Warden cohort to evaluate for association between an SVC patch and reintervention-free survival. RESULTS: In total, 158 patients (122 in the Warden group and 36 in the single-patch group) were identified. The median age at operation was younger for patients in the Warden cohort (5.4 years; interquartile range, 3.3 to 10.2 years) compared with patients in the single-patch cohort (13.3 years; interquartile range, 6.5 to 18.7 years; P < .001). One patient in each cohort died. One patient required reoperation after the Warden procedure for dehiscence of the intracardiac patch. Ten patients required transcatheter reinterventions. Reintervention-free survival was not different between patients in the Warden cohort and patients in the single-patch cohort (P = .54) or within the Warden cohort in patients with an SVC patch (P = .27). When controlling for repair type, older age at repair was associated with longer reintervention-free survival (hazard ratio, 0.81; 95% confidence interval, 0.71 to 0.93; P = .002). CONCLUSIONS: The Warden procedure is a viable option for younger patients requiring supracardiac PAPVR repair, although these younger patients are likely at greatest risk for reintervention regardless of surgical technique.

Recurrent Pulmonary Artery Interventions Following the Norwood Procedure Are Not Associated With Conduit Type.

Given pulmonary artery interventions following the Norwood procedure can recur, the average number of occurrences per patient over time is likely more informative than the crude percentage of patients who required an intervention. Pulmonary artery intervention was defined as any surgical or catheter-based procedure after the Norwood procedure. The number of pulmonary artery interventions for patients with hypoplastic left heart syndrome were compared between patients with modified Blalock-Taussig Shunts (MBTS) and right ventricle-to-pulmonary artery conduits (RVPA) at a single institution from 2011 to 2018. The comparison was replicated using data from the Single Ventricle Reconstruction Trial (SVR), a nonoverlapping dataset. The mean number of pulmonary artery interventions per patient over time (mean cumulative function, MCF) is described using Nelson-Aalen estimates and compared using the pseudo-score test. The number of patients requiring intervention was compared using the chi-square test. Using our institutional dataset, the Norwood operation was performed on 117 patients (59 MBTS, 58 RVPA). In total, 73 patients had a pulmonary artery intervention, including 32 of 58 (55%) after MBTS and 41 of 59 (69%) after RVPA (P= 0.11). The MCF did not vary between cohorts (P = 0.55). Using the SVR trial dataset, 140 of 549 patients required pulmonary artery intervention, including 55 (21%) after MBTS and 85 (30%) after RVPA (P = 0.0090). The MCF did not vary between cohorts (P = 0.067). Although more patients with RVPA than MBTS require pulmonary artery interventions after the Norwood procedure, the MCFs are not different, which may be of greater importance to patients and families.

Mechanical Mitral Valve Replacements in the Pediatric Population.

BACKGROUND: We evaluated the range of prosthetic size-to-weight ratio to optimize valve survival in small children. METHODS: A single-institution retrospective review of mechanical mitral valve replacements from 1995 to 2019 was performed. Prosthetic valve size-to-weight ratio was calculated as the prosthetic valve diameter divided by the patient's operative weight in children less than or equal to 35 kg. Patient death or reoperation on the valve was analyzed by size-to-weight ratio. Identifying a U-shaped distribution of events, patients were stratified as being in the nadir of the distribution or on the edges. RESULTS: Mechanical mitral valve replacements were performed in 56 (75%) children weighing less than or equal to 35 kg. Median follow-up time was 3.7 (interquartile range, 0.46-12) years. Median size-to-weight ratio was 1.5 (interquartile range, 1.0-2.0). A second replacement was required in 15 (27%) patients. Death occurred in 6 (11%) patients, including 3 after reoperation. The nadir of U-shaped distribution of events by size-to-weight ratio was bounded by a ratio from 1 to 2, which included 29 (52%) patients. A size-to-weight ratio from 1 to 2 provided optimal outcomes regardless of patient age. Reoperation-free survival at 5 years was 96% for patients with a ratio from 1 to 2 and 46% for patients with a ratio less than 1 or greater than 2. Patients with size-to-weight ratio 1 to 2 had longer reoperation-free survival than patients with a ratio less than 1 or greater than 2 (P < .001). CONCLUSIONS: Regardless of patient age, in patients less than or equal to 35 kg, optimal reoperation-free survival after prosthetic mitral valve replacement can be obtained by placing a prosthetic valve whose diameter is between 1 and 2 times the patient's weight in kilograms.

Predictors of Transplant-Free Survival After the Norwood Procedure.

BACKGROUND: Birth weight, preterm delivery, and size for gestational age are surrogate markers for development that are commonly used in congenital heart surgery. Understanding the associations of these variables with patient outcomes is of great importance. METHODS: This study included all patients with hypoplastic left heart syndrome who underwent a Norwood procedure at a single institution from 1995 to 2018. Low birth weight was defined as weight less than 2.5 kg, and preterm delivery occurred at less than 37 weeks' gestation. Overall and conditional analyses were performed to evaluate for association with outcomes after the Norwood procedure. Secondary analyses evaluated the association of development measures with postoperative length of stay and ventilator duration. RESULTS: In total, 303 neonates (60% male) underwent the Norwood procedure and were followed for a median of 3.9 years (interquartile range, 0.5 to 10.4 years). Median birth weight was 3.1 kg (interquartile range, 2.8 to 3.4 kg). Patients with low birth weight had decreased transplant-free survival compared with patients with a normal birth weight (hazard ratio, 1.7; 95% confidence interval, 1.03 to 2.82; P = .039). When conditioning on survival to second-stage palliation, patients born small for gestational age had decreased transplant-free survival compared with patients born at appropriate size for gestational age (hazard ratio, 2.8; 95% confidence interval, 1.31 to 6.09; P = .008). Patients delivered preterm had a longer hospital length of stay (median, 55 days vs 31 days; P = .02) and more ventilator days compared with patients delivered at term (median, 7 days vs 4 days; P = .004). CONCLUSIONS: Various developmental markers have differing prognostic importance for patients undergoing the Norwood procedure. Understanding these differences can help guide preoperative decision making and patient selection.

The intraoperative use of recombinant activated factor VII in arterial switch operations.

BACKGROUND: The rate of bleeding complications following arterial switch operation is too low to independently justify a prospective randomised study for benefit from recombinant factor VIIa. We aimed to evaluate factor VIIa in a pilot study. METHODS: We performed a retrospective cohort study of patients undergoing arterial switch operation from 2012 to 2017. Nearest-neighbour propensity score matching on age, gender, weight, and associated cardiac defects was used to match 27 controls not receiving recombinant factor VIIa to 30 patients receiving recombinant factor VIIa. Fisher's exact test was performed to compare categorical variables. Wilcoxon's rank-sum test was used to compare continuous variables between cohorts. RESULTS: Post-operative thrombotic complications were not associated with factor VIIa administration (Odds Ratio (OR) 0.28, 95% CI 0.005-3.77, p = 0.336), nor was factor VIIa administration associated with any re-explorations for bleeding. No intraoperative transfusion volumes were different between the recombinant factor VIIa cohort and controls. Post-operative prothrombin time (10.8 [10.3-12.3] versus 15.9 [15.1-17.2], p < 0.001) and international normalised ratio (0.8 [0.73-0.90] versus 1.3 [1.2-1.4], p < 0.001]) were lower in recombinant factor VIIa cohort relative to controls. CONCLUSIONS: In spite of a higher post-bypass packed red blood cell transfusion requirement, patients receiving recombinant factor VIIa had a similar incidence of bleeding post-operatively. With no difference in thrombotic complications, and with improved post-operative laboratory haemostasis, a prospective randomised study is warranted to evaluate recombinant factor VIIa.