Pulmonary artery banding: still a role for staged bi-ventricular repair of intracardiac shunts?

OBJECTIVES: Although pulmonary artery banding remains a useful palliation in bi-ventricular shunting lesions, single-stage repair holds several advantages. We investigate outcomes of the former approach in high-risk patients. METHODS: Retrospective cohort study including all pulmonary artery banding procedures over 9 years, excluding single ventricle physiology and left ventricular training. RESULTS: Banding was performed in 125 patients at a median age of 41 days (2-294) and weight of 3.4 kg (1.8-7.32). Staged repair was undertaken for significant co-morbidity in 81 (64.8%) and anatomical complexity in 44 (35.2%). The median hospital stay was 14 days (interquartile range 8-33.5) and 14 patients (11.2%) required anatomical repair before discharge. Nine patients died during the initial admission (hospital mortality 7.2 %) and five following discharge (inter-stage mortality 4.8%). Of 105 banded patients who survived, 19 (18.1%) needed inter-stage re-admission and 18 (14.4%) required unplanned re-intervention. Full repair was performed in 93 (74.4%) at a median age of 13 months (3.1-49.9) and weight of 8.5 kg (3.08-16.8). Prior banding, 54% were below the 0.4th weight centile, but only 28% remained so at repair. Post-repair, 5/93 (5.4%) developed heart block requiring permanent pacemaker, and 11/93 (11.8%) required unplanned re-intervention. The post-repair mortality (including repairs during the initial admission) was 6/93 (6.5%), with overall mortality of the staged approach 13.6% (17/125). CONCLUSIONS: In a cohort with a high incidence of co-morbidity, pulmonary artery banding is associated with a significant risk of re-intervention and mortality. Weight gain improves after banding, but heart block, re-intervention, and mortality remain frequent following repair.

Anomalous coronary artery in Tetralogy of Fallot-Feasibility of right ventricular outflow tract stenting as initial palliation.

This study addresses the outcome of right ventricle outflow tract (RVOT) stenting in Tetralogy of Fallot (ToF) with anomalous coronaries crossing the RVOT. RVOT stenting in ToF patients has emerged as an alternative to Blalock Taussig shunting. This is a single center study of patients who underwent RVOT stenting for symptomatic ToF at Birmingham Children's Hospital between 2005 and 2020. A total of 122 patients underwent RVOT stenting as initial palliation over a 15-year period, 10 patients had anomalous coronaries crossing the RVOT (study group) and 112 not (comparative group). Median age of the study group was 72.5 days (interquartile range [IQR]: 28-103) with a weight of 4.7 kg (IQR: 3.5-4.9). No significant differences were found between the two groups regarding the patients' weights and ages, procedure and screening times, or hospital stay. Four had valve sparing stenting. Oxygen saturations increased from a median of 75.5% (IQR: 70-82) to 94.5% (IQR: 90-95), p < 0.002. Postprocedure median hospital stay was 3 days (IQR: 2-6). Six patients underwent interstage catheterization reintervention and one needed early surgical palliation due to stent suboptimal position. Complete repair could be delayed for a median of 11.1 months (IQR: 5.6-19.2). At surgical repair, the patients had a median age of 12.3 months (IQR: 7.5-25.6) and weight of 7.7 kg (IQR: 6.8-10.8). There were no deaths. RVOT stenting in ToF with anomalous coronaries is safe and effective. Dilatable stents should be used when two-stage delayed conduit repair is the default approach.

Bilateral remote ischemic conditioning in children: A two-center, double-blind, randomized controlled trial in young children undergoing cardiac surgery.

Objective: The study objective was to determine whether adequately delivered bilateral remote ischemic preconditioning is cardioprotective in young children undergoing surgery for 2 common congenital heart defects with or without cyanosis. Methods: We performed a prospective, double-blind, randomized controlled trial at 2 centers in the United Kingdom. Children aged 3 to 36 months undergoing tetralogy of Fallot repair or ventricular septal defect closure were randomized 1:1 to receive bilateral preconditioning or sham intervention. Participants were followed up until hospital discharge or 30 days. The primary outcome was area under the curve for high-sensitivity troponin-T in the first 24 hours after surgery, analyzed by intention-to-treat. Right atrial biopsies were obtained in selected participants. Results: Between October 2016 and December 2020, 120 eligible children were randomized to receive bilateral preconditioning (n = 60) or sham intervention (n = 60). The primary outcome, area under the curve for high-sensitivity troponin-T, was higher in the preconditioning group (mean: 70.0 ± 50.9 µg/L/h, n = 56) than in controls (mean: 55.6 ± 30.1 µg/L/h, n = 58) (mean difference, 13.2 µg/L/h; 95% CI, 0.5-25.8; P = .04). Subgroup analyses did not show a differential treatment effect by oxygen saturations (pinteraction = .25), but there was evidence of a differential effect by underlying defect (pinteraction = .04). Secondary outcomes and myocardial metabolism, quantified in atrial biopsies, were not different between randomized groups. Conclusions: Bilateral remote ischemic preconditioning does not attenuate myocardial injury in children undergoing surgical repair for congenital heart defects, and there was evidence of potential harm in unstented tetralogy of Fallot. The routine use of remote ischemic preconditioning cannot be recommended for myocardial protection during pediatric cardiac surgery.

Outcomes of the arterial switch for transposition during infancy using a standardized approach over 30 years.

OBJECTIVES: The aim of this study was to describe the early and late outcomes of the arterial switch for transposition. METHODS: A single-centre retrospective cohort study was conducted to assess the early and late outcomes of arterial switch performed during infancy using a standardized institutional approach between 1988 and 2018, compared by morphological groups. RESULTS: A total of 749 consecutive patients undergoing arterial switch during infancy were included, 464 (61.9%) with intact septum, 163 (21.8%) with isolated ventricular septal defect and 122 (16.3%) with complex transposition with associated lesions, including 67 (8.9%) with Taussig-Bing anomaly. There were 34 early deaths [4.5%, 95% confidence interval (CI) 3.1-6.1] with only 10 (2.6%) early deaths since 2000. Complex morphology (odds ratio 11.44, 95% CI 4.76-27.43) and intramural coronary artery (odds ratio 5.17, 95% CI 1.61-15.91) were identified as the most important risk factors for 90-day mortality. Overall survival was 92.7% (95% CI 90.8-94.6) at 5 years and 91.9% (95% CI 89.9-94.1) at 20 years; in hospital survivors, there were 15 (2.1%) late deaths during a median follow-up of 13.7 years. Cumulative incidence of surgical or catheter reintervention was 16.0% (95% CI 14.5-17.5) at 5 years and 22.7% (95% CI 21.0-24.0) at 20 years; early and late reinterventions were more common in the complex group, with no difference between the other groups. CONCLUSIONS: Using a standardized approach, the arterial switch can be performed with low early mortality, moderate rates of reintervention and excellent long-term survival. Concomitant lesions were the most important risk factor for early death and were associated with increased risk of late reintervention.

Four right ventricle to pulmonary artery conduit types.

OBJECTIVE: The most durable valved right ventricle to pulmonary artery conduit for the repair of congenital heart defects in patients of different ages, sizes, and anatomic substrate remains uncertain. METHODS: We performed a retrospective analysis of 4 common right ventricle to pulmonary artery conduits used in a single institution over 30 years, using univariable and multivariable models of time-to-failure to analyze freedom from conduit dysfunction, reintervention, and replacement. RESULTS: Between 1988 and 2018, 959 right ventricle to pulmonary artery conduits were implanted: 333 aortic homografts, 227 pulmonary homografts, 227 composite porcine valve conduits, and 172 bovine jugular vein conduits. Patients weighed 1.6 to 98.3 kg (median 15.3 kg), and median duration of follow-up was 11.4 years, with 505 (52.2%) conduits developing dysfunction, 165 (17.2%) requiring catheter intervention, and 415 (43.2%) being replaced. Greater patient weight, conduit z-score, type and position, as well as catheter intervention were predictors of freedom from replacement. Multivariable analysis demonstrated inferior durability for smaller composite porcine valve conduits, with excellent durability for larger diameter conduits of the same type. Bovine jugular vein conduit longevity was inferior to that of homografts in all but the smallest patients. Freedom from dysfunction at 8 years was 60.7% for aortic homografts, 72% for pulmonary homografts, 51.2% for composite porcine valve conduits, and 41.3% for bovine jugular vein conduits. Judicious oversizing of the conduit improved conduit durability in all patients, but to the greatest extent in patients weighing 5 to 20 kg. CONCLUSIONS: Pulmonary and aortic homografts had greater durability than xenograft conduits, particularly in patients weighing 5 to 20 kg. Judicious oversizing was the most significant surgeon-modifiable factor affecting conduit longevity.

What tissue bankers should know about the use of allograft heart valves.

Heart valve allografts (usually referred to as 'homografts') have been used in cardiac surgery for over 45 years when they were amongst the first valves ever used. Today they remain an important part of valve replacement and reconstructive surgery, particularly in the field of congenital heart disease. There are currently seven tissue banks on the UK and Eire that procure, prepare and store these homografts for surgical implantation, currently providing around 700 grafts per year. This article reviews the history and applications of homografts and compares their performance and outcomes with current prosthetic alternatives. It also describes the processes of valve procurement and storage and describes their clinical applications, hopefully providing tissue bankers with the surgeon's insight into what is required. Homograft degeneration and the natural history of these tissues is discussed, together with future expectations and developments in homograft valve technology.

Strategies to Minimise Need for Prosthetic Aortic Valve Replacement in Congenital Aortic Stenosis-Value of the Ross Procedure.

To examine the role and outcomes of all interventions for aortic stenosis in children, with focus on freedom from reintervention and the aim to minimise prosthetic aortic valve replacement (pAVR) during childhood. Retrospective analysis of 194 consecutive children who underwent any aortic valve intervention for a biventricular repair strategy at a single institution between 1995 and 2017. Data were obtained from hospital records and follow-up was 100% complete. Over a 22-year period, 194 children underwent total 313 aortic valve procedures: Primary interventions were surgical valvotomy (SV)/surgical repair (SR) in 94 (48.5%), balloon valvuloplasty (BV) in 60 (30.9%), pAVR in 8 (4.1%) and Ross/Ross-Konno procedure in 32 (16.5%). Median age at first intervention was 1.1 years (interquartile range [IQR] 0.1-9.4) and varied with type of intervention: SV/SR were most common in neonates (33, 75%) and infants (35, 68%), whilst BV was most frequent in older children (42, 42%). Operative survival was 99% (2 early deaths, both in neonates with critical aortic stenosis and poor left ventricular function) and 15-year survival was 95%. A Ross procedure was performed in 79 (40.7%) patients over the 15-year study period, 1 of whom required late pAVR for autograft failure. Freedom from any reintervention after SV/SR and BV was 41% and 40% at 10 years, compared to 90% at 10 years with the Ross procedure (P < 0.001). Among neonatal SV/SR and BV, 98% required reintervention during childhood with no difference between groups. Valve morphology did not influence freedom from ultimate valve replacement. In patients who went on to have a Ross procedure, median time from initial intervention to Ross was 2.8 years (IQR 0.1-11.9) in neonates and 6.0 years (IQR 3.1-7.5) in all other age groups. Overall freedom from pAVR was 97% at 10 years and was similar in the SV/SR and BV groups. A strategy of simple valve repair and primary Ross procedure provides excellent survival and good freedom from pAVR. However, reintervention rates after simple interventions for congenital AS are high, especially in younger age groups. The Ross procedure offers the best freedom from reintervention of any technique and wider use of primary Ross in younger age groups should be considered.

Unifocalization cannot rely exclusively on native pulmonary arteries: the importance of recruitment of major aortopulmonary collaterals in 249 cases†.

OBJECTIVES: We sought to define the early and late outcomes of unifocalization based on a classification of the native pulmonary artery (nPA) system and major aortopulmonary collateral arteries (MAPCAs) with a policy of combined recruitment and rehabilitation and to analyse the role of unifocalization by leaving the ventricular septal defect (VSD) open with a limiting right ventricle-pulmonary artery (RV-PA) conduit in borderline cases. METHODS: An analysis of 271 consecutive patients assessed for unifocalization at a single institution between 1988 and 2016 was performed. Patients were classified according to the pulmonary blood supply: group A, unifocalization based on nPA only; group B, based on nPA and MAPCAs; group C, MAPCAs only (absent nPAs). RESULTS: Unifocalization was achieved in 249 (91.9%) cases with an early mortality of 2.8%. Group A included 72 (28.9%) patients, group B 119 (47.8%) patients and group C 58 (23.3%) patients with no difference in early survival between groups. Survival at 5, 10 and 15 years was 90.0% (85.9-94.3), 87.2% (83.5-91.2) and 82.3% (75.2-89.9), respectively. Late survival in groups A and B was similar but 10- and 15-year survival in group C decreased to 79.2% (68.2-92.1) and 74.3% (61.1-90.4) (P = 0.02), respectively. A mean of 1.9 (±0.6) MAPCAs were recruited per patient (range 0-6). The VSD was left open with a limiting RV-PA conduit in 97 (39.0%) cases, but subsequently closed in 48 patients, giving a total of 200 (80.3%) patients achieving VSD closure (full repair). Delaying VSD closure was not associated with increased risk for early or late survival. A central shunt to rehabilitate the nPAs was used in 56 (22.5%) cases. This was associated with a reduction in the number of MAPCAs recruited, but still required a mean of 1.8 (±0.5) MAPCAs recruited per patient to achieve unifocalization. In multivariate risk analysis, those suitable for single-stage full repair had the best long-term outcomes. Group C anatomy was associated with poor late survival compared to groups A and B (hazard ratio 2.7). CONCLUSIONS: Survival is maximized by a combined approach of rehabilitation and recruitment. MAPCAs should always be recruited if they supply areas with absent nPA supply. A strategy of leaving the VSD open with a limiting RV-PA conduit is a safe and effective way of managing borderline cases.

Fate of the Left Ventricular Outflow Tract After Rastelli With Selective Infundibular Muscle Resection.

BACKGROUND: The Rastelli procedure has been criticized for a high rate of left ventricular outflow tract obstruction (LVOTO) and translocation procedures have been proposed as an alternative. Infundibular resection can be performed during Rastelli to optimize the outflow tract. This study examines whether a selective policy to enlarge the outflow tract improves Rastelli outcomes across all morphological variants. METHODS: Single institution 29-year experience in 105 patients. Patients were classified into transposition of the great arteries with ventricular septal defect, congenitally corrected transposition of the great arteries with ventricular septal defect, and double outlet right ventricle morphology groups. The infundibular muscle was routinely resected if prominent, in 28 cases. RESULTS: Early mortality was 1.9% (2 of 105) and actuarial survival was 95.4% (95% confidence interval [CI], 89% to 99%) at 1 year, 92.9% (95% CI, 85% to 97%) at 5 years, and 84.5% (95% CI, 74% to 92%) at 10 years. The cumulative freedom from LVOTO was 99% (95% CI, 96% to 100%), 97% (95% CI, 92% to 99%), and 90% (95% CI, 88% to 96%) at 1, 5, and 10 years, respectively. The incidence was similar in all morphological groups and those undergoing infundibular resection were not at higher risk of late LVOTO. Eleven patients required surgical reoperation on the left ventricular outflow tract over a median follow-up period of 8.5 years, with no mortality, although 2 of these patients developed complete heart block. Left ventricular function was well preserved in 98.1% of all cases, including all of those requiring left ventricular outflow tract reoperation. CONCLUSIONS: The Rastelli is a safe procedure that can be applied in a variety of morphological variants. LVOTO remains a late complication of Rastelli, but can be minimized by concomitant infundibular muscle resection. Late reoperation is safe and ventricular function is well preserved in greater than 95% of cases at late follow-up. The operation has stood the test of time and avoids many of the risks of translocation procedures.

Long-Term Outcome of Interrupted Arch Repair With Direct Anastomosis and Homograft Augmentation Patch.

BACKGROUND: This study analyzed outcomes of interrupted aortic arch (IAA) repair using a standardized technique to interpret the role of the arch repair on late outcomes in a complex and heterogeneous group of patients. METHODS: This single institution study covered the period from 1988 to 2015. A total of 120 cases of IAA were divided into four groups: IAA with ventricular septal defect (VSD) (n = 38), IAA with a Norwood or Damus-Kaye-Stansel procedure (n = 41), IAA with truncus arteriosus (n = 24), and a miscellaneous group (n = 17). Arch repair was performed using a standard technique of direct anastomosis with homograft patch augmentation. RESULTS: IAAs were predominantly type B (n = 81, 68%), and type A (n = 34, 28%), with a significant association of type B with truncus arteriosus and of type A with an aortopulmonary window (p < 0.01). Survival was similar in all groups. The incidence of catheter or surgical reintervention was 18% (confidence interval [CI], 10% to 25%) at 5 years and 18% (CI, 10% to 25%) at 10 years, with catheter reintervention more common and occurring before 18 months. Surgical reintervention occurred in 7% (CI, 2% to 13%) at 5 and 10 years and at 10 years the reintervention rate was lower in the group with truncus arteriosus (0%) and in the group with a Norwood or Damus-Kaye-Stansel procedure (5%). There was no bronchial obstruction or aortic aneurysm. The Cox proportional hazard model showed that weight at surgery <2.5 kg and era of surgery were predictive of outcome, with surgical mortality rates in all variants dropping to 8.3% in the last 15 years of the study. CONCLUSIONS: Repair of IAA using direct anastomosis and patch augmentation is applicable to all variants and provides good long-term arch patency. Survival is strongly associated with weight at surgery.

A randomized comparison of off-pump and on-pump multivessel coronary-artery bypass surgery.

BACKGROUND: The effect of the use of coronary-artery bypass surgery without cardiopulmonary bypass and cardiac arrest ("off pump") on graft patency remains uncertain. We undertook a prospective, randomized, controlled study to compare graft-patency rates and clinical outcomes in off-pump surgery with conventional, "on-pump" surgery. METHODS: We randomly assigned 50 patients to undergo on-pump coronary-artery bypass grafting and 54 to undergo off-pump surgery. Surgical and anesthetic techniques were standardized for both groups. Clinical outcomes and troponin T levels were measured. Three months later, the patients underwent coronary angiography, including quantitative analysis. RESULTS: The mean age of the patients was 63 years, and 87 percent were men. The on-pump group received a mean of 3.4 grafts, and the off-pump group 3.1 (P=0.41). There were no deaths. There was no significant difference in the median postoperative length of stay between the two groups (seven days in each group). The area under the curve of troponin T levels was higher during the first 72 hours in the on-pump group than in the off-pump group (30.96 hr x microg per liter vs. 19.33 hr x microg per liter, P=0.02). At three months, 127 of 130 grafts were patent in the on-pump group (98 percent), as compared with 114 of 130 in the off-pump group (88 percent, P=0.002). The patency rate was higher for all graft territories in the on-pump group than in the off-pump group. CONCLUSIONS: In this randomized study, off-pump coronary surgery was as safe as on-pump surgery and caused less myocardial damage. However, the graft-patency rate was lower at three months in the off-pump group than in the on-pump group, and this difference has implications with respect to the long-term outcome.