Managing Bilateral Discontinuous Pulmonary Arteries of Ductal Origin in Single-Ventricle Anatomy.

BACKGROUND: We describe outcomes and management strategies for single-ventricle and bilaterally discontinuous pulmonary arteries (PAs) originating from bilateral ductus arteriosus. METHODS: We reviewed 22 patients with aforementioned anatomy and PA centralization from 1995 to 2023, excluding those with biventricular repair. RESULTS: Median age at centralization was 9 days (minimum-maximum, 0 days-2 years). Centralization was performed with systemic-to-pulmonary shunt (n =20 [91%]; 2 after bilateral ductal stents) or bidirectional cavopulmonary connection (n = 2 [9%]) using pericardial roll (n = 14 [64%]), patch-augmented direct anastomosis (n = 7 [32%]), and interposition graft (n = 1 [5%]) techniques. Concurrent total anomalous pulmonary venous connection (TAPVC, n = 11 [50%]) was associated with significantly inferior survival (P = .01). Five patients (23%) died at a median of 59 days (minimum-maximum, 6-257 days) after centralization, all with noncardiac TAPVC. At the latest follow-up for 17 survivors (median, 13.5 years; minimum-maximum, 0.5-25.1 years after centralization), 12 completed Fontan, 4 completed second-stage palliation, and 1 received a transplant before second-stage palliation. PA reintervention was required in 14 patients (64%), including 3 with reoperations independent of staged palliation. Echocardiography from baseline to before the second stage demonstrated branch PA growth with significantly increased diameters (left, P = .0006; right, P = .0002); z-scores significantly increased for right (P = .004) but not left (P = .11). CONCLUSIONS: Successful single-ventricle palliation is possible, although high risk, for patients with bilateral discontinuous ductal PAs. Early postcentralization mortality remains substantial, particularly with associated noncardiac TAPVC. Many require reintervention to maintain PA growth, typically concurrently with staged palliation.

Labyrinthine cor triatriatum sinister in fetal hypoplastic left heart syndrome is associated with poor outcomes.

OBJECTIVES: A subset of hypoplastic-left-heart-syndrome (HLHS) fetuses have a complex cor-triatriatum sinister that we named "labyrinthine-cor (L-cor)". We sought to determine the prevalence of L-cor in HLHS fetuses and hypothesized that it is associated with increased mortality. METHODS: This single-center retrospective cohort study included all HLHS fetuses from January 2010-December 2020. Fetuses with other hypoplastic-left-heart variants, inadequate images, lack of follow-up and fetal atrial-septal interventions were excluded. RAS was defined as the ratio of pulmonary-vein forward-to-reverse velocity-time-integral (VTI) ≤ 5 and severe-RAS defined as VTI-ratio <3. Kaplan-Meier survival-analysis was performed for the primary outcome of transplant-free survival for 62 weeks after gestational-age of 30 weeks (∼1 year). RESULTS: Of the 156 consecutive fetuses with HLHS, 11 (7.7%) had L-cor and 8/11 (72.7%) of these had RAS. When compared to HLHS-RAS without L-cor, fetuses with HLHS-RAS and L-cor were less likely to survive to 28 days (87% vs. 62.5%, p = 0.017) and to 1 year (69.6% vs. 25%, p = 0.029). When comparing by survival analysis, fetuses with severe-RAS with L-cor had lower survival compared severe-RAS without L-cor (p = 0.020). CONCLUSION: L-cor in fetal HLHS is associated with increased mortality. Recognition of this finding is important for prognostication and atrial-septal-intervention planning.

Long-Term Outcomes of Ascending Sliding Arch Aortoplasty.

Background: Coarctation of the aorta can be associated with significant hypoplasia of the aortic arch. In contrast to patch aortoplasty, ascending sliding arch aortoplasty uses viable autologous tissue for potential growth in children. We reviewed the mid- to long-term outcomes of this technique. Methods: Between 2002 and 2023, 28 patients underwent ascending sliding arch aortoplasty for the patients with coarctation of the aorta (n = 22) and interrupted aortic arch (n = 2). Four patients underwent previous surgical coarctation repair at other institutions. The median patient age and body weight were 28.5 months (3 weeks to 15.6 years) and 13.4 kg (3.7-70 kg), respectively. Results: Although one patient had a recurrent nerve injury postoperatively, there were no other major morbidities or mortalities. The last follow-up echocardiography demonstrated that the mean peak velocity improved from 3.9 ± 0.6 to 0.9 ± 0.8 m/s, and the pressure gradient improved from 63.6 ± 21.5 to 7.1 ± 7.7 mm Hg. The postoperative diameters of the ascending aorta, proximal arch, distal arch, and isthmus all increased significantly. The mean postoperative length of stay was 5.9 ± 2.1 days, and the median follow-up time was 7.3 years (10 days to 20.5 years). No reoperation or catheterization-based intervention was performed for residual coarctation. Conclusions: Ascending sliding arch aortoplasty is safe and effective for treating coarctation of the aorta with aortic arch hypoplasia. This technique is applicable for children ranging in size from neonates to older children (or adolescents), recurrent coarctation cases, and provides complete relief of narrowing by utilizing viable native aortic tissue.

Anomalous Aortic Origin of a Coronary Artery.

BACKGROUND: Although anomalous aortic origin of a coronary artery (AAOCA) is associated with risk of sudden cardiac arrest (SCA), there is a spectrum of disease, with the appropriate management for many remaining unclear. Increasing data warrant review for an updated perspective on management. METHODS: A panel of congenital cardiac surgeons, cardiologists, and imaging practitioners reviewed the current literature related to AAOCA and its management. Survey of relevant publications from 2010 to the present in PubMed was performed. RESULTS: The prevalence of AAOCA is 0.4% to 0.8%. Anomalous left coronary artery is 3 to 8 times less common than anomalous right coronary, but carries a much higher risk of SCA. Nevertheless, anomalous right coronary is not completely benign; 10% demonstrate ischemia, and it remains an important cause of SCA. Decision-making regarding which patients should be recommended for surgical intervention includes determining anatomic features associated with ischemia, evidence of ischemia on provocative testing, and concerning cardiovascular symptoms. Ischemia testing continues to prove challenging with low sensitivity and specificity, but the utility of new modalities is an active area of research. Surgical interventions focus on creating an unobstructed path for blood flow and choosing the appropriate surgical technique given the anatomy to accomplish this. Nontrivial morbidity has been reported with surgery, including new-onset ischemia. CONCLUSIONS: A proportion of patients with AAOCA demonstrate features and ischemia that warrant surgical intervention. Continued work remains to improve the ability to detect inducible ischemia, to risk stratify these patients, and to provide guidance in terms of which patients warrant surgical intervention.

Myocardial bridges in a pediatric population: Outcomes following a standardized approach.

OBJECTIVE: To describe clinical, functional, surgical, and outcomes data in pediatric patients with a myocardial bridge (MB) evaluated and managed following a standardized approach. METHODS: Prospective observational study included patients evaluated in the Coronary Artery Anomalies Program. Anatomy was determined by computed tomography angiography, myocardial perfusion by stress perfusion imaging, and coronary hemodynamic assessment by cardiac catheterization. RESULTS: In total, 39 of 42 patients with a complete evaluation for MB were included (December 2012 to June 2022) at a median age of 14.1 years (interquartile range, 12.2-16.4). Sudden cardiac arrest occurred in 3 of 39 (8%), exertional symptoms in 14 (36%), and no/nonspecific symptoms in 7 (18%) patients. Exercise stress test was abnormal in 3 of 34 (9%), stress perfusion imaging in 8 of 34 (24%), and resting instantaneous wave-free ratio ≤0.89 or diastolic dobutamine fractional flow reserve ≤0.80 in 11 of 21 (52%) patients. As a result, 15 of 39 (38%) patients were determined to have hemodynamically significant MB, 1 of 15 patients started beta-blocker, and 14 of 15 were referred for surgery. Myotomy (n = 11) and coronary bypass (n = 1) were performed successfully, resulting in improved symptoms and stress testing results. One patient required pericardiocentesis postoperatively, and all were discharged without other complications. At median follow-up time of 2.9 (1.8-5.8) years, all (except 2 pending surgery) were doing well without exercise restriction. CONCLUSIONS: Pediatric patients with MB can present with myocardial ischemia and sudden cardiac arrest. Provocative stress test and intracoronary hemodynamic tests helped risk-stratify symptomatic patients with MB and concern for ischemia. Surgical repair was safe and effective in mitigating exertional symptoms and stress test results, allowing patients to return to exercise without restriction.

Cardiac Arrest With or Without Need for Extracorporeal Life Support After Congenital Cardiac Surgery.

BACKGROUND: Postoperative cardiac arrest (CA) with or without need for extracorporeal cardiopulmonary resuscitation (ECPR) is one of the most significant complications in the early postoperative period after pediatric cardiac operation. The objective of this study was to develop and to validate a predictive model of postoperative CA with or without ECPR. METHODS: In this retrospective cohort study, we reviewed data from patients who underwent cardiac surgery with cardiopulmonary bypass (CPB) between July 20, 2020, and December 31, 2021. Variables included demographic data, presence of preoperative risk factors, The Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery mortality categories, perioperative data, residual lesion score (RLS), and vasoactive-inotropic score (VIS). We used multivariable logistic regression analysis to develop a predictive model. RESULTS: The incidence of CA with or without ECPR was 4.4% (n = 24/544). Patients who experienced postoperative CA with or without ECPR were younger (age, 130 [54-816.5] days vs 626 [127.5-2497.5] days; P < .050) and required longer CPB (253 [154-332.5] minutes vs 130 [87-186] minutes; P < .010) and cross-clamp (116.5 [75.5-143.5] minutes vs 64 [30-111] minutes; P < .020) times; 37.5% of patients with an outcome had at least 1 preoperative risk factor (vs 16.9%; P < .010). Our multivariable logistic regression determined that the presence of at least 1 preoperative risk factor (P = .005), CPB duration (P = .003), intraoperative residual lesion score (P = .009), and postsurgery vasoactive-inotropic score (P = .010) were predictors of the incidence of CA with or without ECPR. CONCLUSIONS: We developed a predictive model of postoperative CA with or without ECPR after congenital cardiac operation. Our model performed better than the individual scores and risk factors.

Retrospective Comparison of Recombinant Activated Factor VII Versus 4-Factor Prothrombin Complex Concentrate in Cardiac Surgical Patients.

OBJECTIVES: To compare the incidences of postoperative thrombotic complications, transfusion of blood products, and chest tube output in congenital cardiac surgical patients who received either recombinant activated factor VII (rFVIIa) or 4-factor prothrombin complex concentrate (4F-PCC). DESIGN: We performed a retrospective study. SETTING: Patients who underwent surgery at a tertiary academic hospital. PARTICIPANTS: Pediatric patients who underwent cardiac surgery. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Data were obtained from the Society of Thoracic Surgeons and the Pediatric Cardiac Critical Care Consortium databases, as well as from manual chart review. Adjusted p values were obtained from multivariate regression using age (days), surgeon (number), cardiopulmonary bypass time (minutes), and need for deep hypothermic circulatory arrest (yes/no). A total of 55 patients were included in the 4F-PCC group, and 89 in the rFVIIa group. The median dose of rFVIIa was 77 mcg/kg (46-88), and the median dose of 4F-PCC was 31 IU/kg (24-43). The incidences of thrombotic complications were 8% in the 4F-PCC group and 30% in the rFVIIa group (adjusted p = 0.023). No difference was reported between the groups regarding chest tube output on days 1 and 2 or transfusion of blood products. Using a sensitivity analysis with propensity matching, the incidence of thrombosis was 10% in the 4F-PCC group (n = 38), and 31% in the rFVIIa group (n = 39) (p = 0.036). No difference was reported in terms of bleeding or transfusion. CONCLUSIONS: This retrospective study suggested that the administration of rFVIIa was associated with a higher risk of thrombotic complications when compared to 4F-PCC, without benefits in terms of bleeding and transfusions.

Comparing palliation strategies for single-ventricle anatomy with transposed great arteries and systemic outflow obstruction.

Objective: Patients with complex single-ventricle anatomy with transposed great arteries and systemic outflow obstruction (SV-TGA-SOO) undergo varied initial palliation with ultimate goal of Fontan circulation. We examine a longitudinal experience with multiple techniques, including the largest published cohort following palliative arterial switch operation (pASO), to describe outcomes and decision-making factors. Methods: Neonates with SV-TGA-SOO who underwent initial surgical palliation from 1995 to 2022 at a single institution were retrospectively reviewed. Results: In total, 71 neonates with SV-TGA-SOO underwent index surgical palliation at a median age of 7 days (interquartile range, 6-10) by pASO (n = 23), pulmonary artery band (PAB) with or without arch repair (n = 25), or modified Norwood with Damus-Kaye-Stansel aortopulmonary amalgamation (n = 23). Single-ventricle pathology included double-inlet left ventricle (n = 37, 52%), tricuspid atresia (n = 27, 38%), and others (n = 7, 10%). All mortalities (n = 5, 7%) occurred in the first interstage period after PAB (n = 3) and Norwood (n = 2). Subaortic obstruction in the PAB group was addressed by operative resection (n = 10 total, 7 at index operation) and/or delayed aortopulmonary amalgamation (n = 13, 52%). Two patients with pASO (9%) had early postoperative coronary complications, 1 requiring operative revision. Median follow-up for survivors was 10.4 years (interquartile range, 4.5-16.6 years). Comparing patients by their initial palliation type, notable significant differences included size of bulboventricular foramen, weight at initial operation, operation duration, postoperative length of stay, time to second-stage palliation, multiple pulmonary artery reinterventions, and left pulmonary artery interventions. There were no significant differences in overall survival, Fontan completion, reintervention-free survival in the first interstage period, pulmonary artery reintervention-free survival, long-term systemic valve competency, or ventricular dysfunction. Conclusions: Excellent mid- to long-term outcomes are achievable following neonatal palliation for SV-TGA-SOO via pASO, PAB, and modified Norwood, with comparable survival and Fontan completion. Initial palliation strategy should be individualized to optimize anatomy and physiology for successful Fontan by ensuring an unobstructed subaortic pathway and accessible pulmonary arteries. pASO is a reasonable strategy to consider for these heterogeneous lesions.

Invasive Coronary Assessment in a 9-Year-Old With Anomalous Aortic Origin of the Left Coronary Artery.

A previously healthy nine-year-old boy with anomalous aortic origin of the left coronary artery (AAOLCA) with high-risk anatomy demonstrated negative stress on magnetic resonance imaging. Invasive cardiac catheterization for intracoronary flow measurement was performed and demonstrated compromised coronary flow during pharmacologic stress and significant stenosis on angiography. The patient underwent surgical intervention with normalization of coronary flow upon postoperative evaluation. Invasive intracoronary flow determination with angiography under provocative stress is emerging as a critical data point for risk stratification and management decision-making in high-risk AAOLCA patients with negative noninvasive perfusion studies.

Clinical Presentation and Medium-Term Outcomes of Children With Anomalous Aortic Origin of the Left Coronary Artery: High-Risk Features Beyond Interarterial Course.

BACKGROUND: Anomalous aortic origin of the left coronary artery (AAOLCA) confers a rare, but significant, risk of sudden cardiac death in children. Surgery is recommended for interarterial AAOLCA, and other subtypes considered benign. We aimed to determine the clinical characteristics and outcomes of 3 AAOLCA subtypes. METHODS: All patients with AAOLCA <21 years old were prospectively enrolled (December 2012-November 2020), including group 1: AAOLCA from the right aortic sinus with interarterial course, group 2: AAOLCA from the right aortic sinus with intraseptal course, and group 3: AAOLCA with a juxtacommissural origin between the left and noncoronary aortic sinus. Anatomic details were assessed using computed tomography angiography. Provocative stress testing (exercise stress testing and stress perfusion imaging) was performed in patients >8 years old or younger if concerning symptoms. Surgery was recommended for group 1 and in select cases in group 2 and group 3. RESULTS: We enrolled 56 patients (64% males) with AAOLCA (group 1, 27; group 2, 20; group 3, 9) at median age of 12 years (interquartile range, 6-15). Intramural course was common in group 1 (93%) compared with group 3 (56%) and group 2 (10%). Seven (13%) presented with aborted sudden cardiac death (group 1, 6/27; group 3, 1/9); 1 (group 3) with cardiogenic shock. Fourteen/42 (33%) had inducible ischemia on provocative testing (group 1, 32%; group 2, 38%; group 3, 29%). Surgery was recommended in 31/56 (56%) patients (group 1, 93%; group 2, 10%; and group 3, 44%). Surgery was performed in 25 patients at a median age 12 (interquartile range, 7-15) years; all have been asymptomatic and free from exercise restrictions at median follow-up of 4 (interquartile range, 1.4-6.3) years. CONCLUSIONS: Inducible ischemia was noted in all 3 AAOLCA subtypes while most aborted sudden cardiac deaths occurred in interarterial AAOLCA (group 1). Aborted sudden cardiac death and cardiogenic shock may occur in AAOLCA with left/nonjuxtacommissural origin and intramural course, thus also deemed high-risk. A systematic approach is essential to adequately risk stratify this population.

Comprehensive management of type A acute aortic dissection in the paediatric population with ACTA 2 mutation: case reports and literature review of paediatric aortic dissection.

Acute aortic dissection in the paediatric population is rare but lethal. We present two paediatric cases of type A acute aortic dissection that required emergent procedures and were later found to have genetic mutations. High index of suspicion, early clinical diagnosis, prompt treatment, the advantageous collaboration between the paediatric team and aortic surgeons, and familial genetic testing are paramount to achieve a good outcome.

Ischemia in Anomalous Aortic Origin of a Right Coronary Artery: Large Pediatric Cohort Medium-Term Outcomes.

BACKGROUND: Anomalous aortic origin of a right coronary artery may cause myocardial ischemia and sudden death in the young. Data on myocardial ischemia or longitudinal outcomes are sparse in pediatric anomalous aortic origin of a right coronary artery population. METHODS: Patients <21 years with anomalous aortic origin of a right coronary artery were prospectively enrolled. Computerized tomography angiography defined morphology. Exercise stress test and stress perfusion imaging (sPI) were performed if >7 years or younger with concern for ischemia. High-risk features included intramural length, slit-like/hypoplastic ostium, exertional symptoms, or evidence of ischemia. RESULTS: A total of 220 patients (60% males) were enrolled December 2012 to April 2020 at a median age 11.4 years (interquartile range, 6.1-14.5), including 168 (76%) with no/nonexertional symptoms (group 1) and 52 (24%) with exertional chest pain/syncope (group 2). Computerized tomography angiography was available in 189/220 (86%), exercise stress test in 164/220 (75%), and sPI in 169/220 (77%). Exercise stress test was positive in 2/164 (1.2%) patients in group 1, both had positive sPI. Inducible ischemia (sPI) was detected in 11/120 (9%) in group 1 and 9/49 (18%) in group 2 (P=0.09). Intramural length was similar in patients with/without ischemia (5 [interquartile range, 4-7] versus 5 [interquartile range, 4-7] mm; P=0.65). Surgery was recommended in 56/220 (26%) patients with high-risk features. In 52 surgical patients (38 unroofing, 14 reimplantation), all subjects were alive and have returned to exercise at last median follow-up of 4.6 (interquartile range, 2.3-6.5) years. CONCLUSIONS: Anomalous aortic origin of a right coronary artery patients can present with inducible ischemia on sPI despite symptoms or intramural length. Exercise stress test is a poor predictor of ischemia and caution should be given to determine low-risk based solely on this assessment. All patients are alive at medium-term follow-up.

Evolution of surgical repair of intraseptal anomalous left coronary artery with myocardial ischaemia.

BACKGROUND: Anomalous aortic origin of the left coronary artery with intraseptal course is a rare coronary anomaly associated with an increased risk of myocardial ischaemia. The role and techniques for surgical intervention are evolving, with numerous novel surgical techniques for this challenging anatomy reported in the last 5 years. We report our single-centre experience with surgical repair of intraseptal anomalous left coronary artery in the paediatric population, including clinical presentation, evaluation, and short- to mid-term outcomes. METHODS: All patients with coronary anomalies presenting to our institution undergo standardised clinical evaluation. Five patients aged 4 to 17 years underwent surgical intervention for intraseptal anomalous aortic origin of the left coronary artery between 2012 and 2022. Surgical techniques included coronary artery bypass grafting (n = 1), direct reimplantation with limited supra-arterial myotomy via right ventriculotomy (n = 1), and transconal supra-arterial myotomy with right ventricular outflow tract patch reconstruction (n = 3). RESULTS: All patients had evidence of haemodynamically significant coronary compression, and three had evidence of inducible myocardial ischaemia pre-operatively. There were no deaths or major complications. Median follow-up was 6.1 months (range 3.1-33.4 months). Patients who underwent supra-arterial myotomy (with or without reimplantation) had improved coronary flow and perfusion based on stress imaging and catheterisation data. CONCLUSIONS: Surgical approaches to intraseptal anomalous left coronary artery with evidence of myocardial ischaemia continue to evolve, with new techniques demonstrating promising improvement in coronary perfusion. Further studies are warranted to determine long-term outcomes and refine indications for repair.

Transection and reimplantation of anomalous right coronary artery from single left coronary artery in a collegiate athlete.

Coronary artery anomalies may induce myocardial ischaemia and sudden cardiac death when associated with areas of compression or stenosis. We present a case of transection and reimplantation of an anomalous interarterial right coronary artery arising from a single left main coronary artery. The 18-year-old collegiate athlete had exertional chest pain and haemodynamically significant compromise to coronary blood flow.

Intramural course of an anomalous left coronary artery is not always associated with a slit-like ostium.

Anomalous aortic origin of the left coronary artery from an incorrect aortic sinus has been reported as the second most common causes of sudden cardiac arrest in young athletes. Intramural course of the proximal left coronary artery is considered a high-risk morphology. It is associated with a slit-like ostium and elliptical shape of the proximal artery. In this case, all pre-operative cardiac images demonstrated a round ostium and round luminal shape of the left coronary artery, which suggested no evidence of intramural course. On intraoperative inspection, although the ostium and proximal left coronary artery appeared round, the patient had a long intramural course of the left coronary artery which our surgeons performed a successful unroofing procedure. The post-operative images showed a patent new ostium from the correct aortic sinus. These findings are very unusual and proved that we should not exclude intramural course even in the absence of a slit-like ostium and elliptical shape of the proximal left coronary artery.

Anomalous Aortic Origin of Coronary Arteries in Children: Postoperative High-risk Anatomic Features.

BACKGROUND: This study aimed to assess postoperative presumed high-risk anatomic features (HRAFs) by using computed tomographic angiography (CTA) in patients with anomalous aortic origin of a coronary artery (AAOCA) after surgical unroofing vs transection and reimplantation (TAR) if unroofing was thought to provide unsatisfactory results. METHODS: The study included 62 children with postoperative CTA performed at a median of 3 months (interquartile range, 3-4 months) after unroofing (n = 45) and TAR (n = 17). HRAFs included slitlike ostium, intramural course, acute angle takeoff (<45o), interarterial course, proximal stenosis >50%, or course through a thickened intercoronary pillar. RESULTS: Median age at surgery was 13.8 years (interquartile range, 10.5-15.8 years). None of the patients had a slitlike ostium or an intramural course on postoperative CTA. Acute takeoff was seen in 100% after unroofing and in 2 of 17 (12%) after TAR (P < .001). After unroofing, the interarterial course improved to 35 of 45 (78%) from 43 of 45 (96%) (P = .003), and a thickened intercoronary pillar improved to 10 of 45 (22%) from 22 of 45 (49%) (P = .0001), compared with none seen after TAR. Preoperative intramural length <5 mm was associated with a postoperative thickened intercoronary pillar in right AAOCA after unroofing (P = .0004). Severe coronary stenosis occurred in 2 of 17 (12%) after TAR, and both patients needed urgent revision procedures. All patients except 2 (97%) returned to exercise activities at a median follow-up of 4.9 years (range, 0.6-9.2 years). CONCLUSIONS: The slitlike ostium and intramural course resolved in all patients. Residual acute angle takeoff, an interarterial course, and mild coronary narrowing related to a thickened intercoronary pillar were common after unroofing. TAR allows resolution of all HRAFs, although severe narrowing requiring surgical revision happened only in TAR. Long-term studies are needed to understand the clinical significance of these residual presumed HRAFs.

Is Exercise Stress Testing Useful for Risk Stratification in Anomalous Aortic Origin of a Coronary Artery?

Data on maximal exercise-stress-testing (m-EST) in anomalous-aortic-origin-of-coronary-arteries (AAOCA) is limited and correlation with stress perfusion imaging has not been demonstrated. AAOCA patients ≤20 years were prospectively enrolled from 6/2014-01/2020. A m-EST was defined as heart rate >85%ile on ECG-EST and respiratory-exchange-ratio ≥1.05 on cardiopulmonary-exercise-testing (CPET). Abnormal m-EST included significant ST-changes or high-grade arrhythmia, V̇O2max and/or O2 pulse <85% predicted, or abnormal O2 pulse curve. A (+) dobutamine-stress cardiac-magnetic-resonance-imaging (+DS-CMR) had findings of inducible-ischemia. Outcomes: (1) Differences in m-EST based on AAOCA-type; (2) Assuming DS-CMR as gold-standard for detection of inducible ischemia, determine agreement between m-EST and DS-CMR. A total of 155 AAOCA (right, AAORCA = 126; left, AAOLCA = 29) patients with a median (IQR) age of 13 (11-15) years were included; 63% were males and a m-EST was completed in 138 (89%). AAORCA and AAOLCA had similar demographic and m-EST characteristics, although AAOLCA had more frequently evidence of inducible ischemia on m-EST (P = 0.006) and DS-CMR (P = 0.007). Abnormal O2 pulse was significantly associated with +DS-CMR (OR 5.3, 95% CI 1.6-18,P = 0.005). Sensitivity was increased with addition of CPET to ECG-EST (to 58% from 19%). There was no agreement between m-EST and DS-CMR for detection of inducible ischemia. A m-EST has very low sensitivity for detection of inducible ischemia in AAOCA, and sensitivity is increased with addition of CPET. Stress perfusion abnormalities on DS-CMR were notconcordant with m-EST findings and adjunctive testing should be considered for clinical decision making in AAOCA.

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.

Pattern, behavior, and clinical implications of electrocardiographic changes in patients undergoing repair of anomalous aortic origin of coronary arteries.

OBJECTIVES: Surgical repair in anomalous aortic origin of a coronary artery aims at mitigating the risk of sudden cardiac death in a subset of patients. The pattern and behavior of electrocardiogram changes in a large cohort of these patients are lacking. We aim to describe postoperative electrocardiogram changes in this population and its clinical implications on follow-up. METHODS: All patients aged less than 21 years who underwent surgical repair for anomalous aortic origin of a coronary artery between December 2012 and June 2020 at our institution were considered for inclusion. Electrocardiograms were reviewed at 5 defined time intervals, from preoperative to 90-day follow-up, with attention to significant findings of ST-segment changes, abnormal T waves, and pathologic Q waves. The electrocardiogram changes were analyzed for correlation with surgical reintervention and medium-term outcomes. RESULTS: Sixty-two patients met inclusion criteria (median age 13.7 years, 61% male). ST-segment changes in the initial postoperative period were seen in 52 patients (84%), all resolving over time. Abnormal T waves were seen in 19 patients (31%), occurred commonly at the predischarge period, and mostly resolved over time. Pathologic Q waves were observed in only 1 patient and associated with reintervention due to coronary artery stenosis. There was no association between postoperative electrocardiogram changes and inducible myocardial ischemia, ventricular dysfunction, or restriction from exercise at follow-up. CONCLUSIONS: ST-segment changes and T-wave abnormalities are commonly seen in the postoperative period after anomalous aortic origin of a coronary artery repair, tend to resolve over time, and are not associated with adverse medium-term outcomes. Pathologic Q waves were associated with the need for early coronary reintervention.