Cardiac Magnetic Resonance Imaging to Determine Single Ventricle Function in a Pediatric Population is Feasible in a Large Trial Setting: Experience from the Single Ventricle Reconstruction Trial Longitudinal Follow up.

The Single Ventricle Reconstruction (SVR) Trial was a randomized prospective trial designed to determine survival advantage of the modified Blalock-Taussig-Thomas shunt (BTTS) vs the right ventricle to pulmonary artery conduit (RVPAS) for patients with hypoplastic left heart syndrome. The primary aim of the long-term follow-up (SVRIII) was to determine the impact of shunt type on RV function. In this work, we describe the use of CMR in a large cohort follow up from the SVR Trial as a focused study of single ventricle function. The SVRIII protocol included short axis steady-state free precession imaging to assess single ventricle systolic function and flow quantification. There were 313 eligible SVRIII participants and 237 enrolled, ages ranging from 10 to 12.5 years. 177/237 (75%) participants underwent CMR. The most common reasons for not undergoing CMR exam were requirement for anesthesia (n = 14) or ICD/pacemaker (n = 11). A total of 168/177 (94%) CMR studies were diagnostic for RVEF. Median exam time was 54 [IQR 40-74] minutes, cine function exam time 20 [IQR 14-27] minutes, and flow quantification time 18 [IQR 12-25] minutes. There were 69/177 (39%) studies noted to have intra-thoracic artifacts, most common being susceptibility artifact from intra-thoracic metal. Not all artifacts resulted in non-diagnostic exams. These data describe the use and limitations of CMR for the assessment of cardiac function in a prospective trial setting in a grade-school-aged pediatric population with congenital heart disease. Many of the limitations are expected to decrease with the continued advancement of CMR technology.

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.

Computational Assessment of Hemodynamic Significance in Patients With Intramural Anomalous Aortic Origin of the Coronary Artery Using Virtually Derived Fractional Flow Reserve and Downstream Microvascular Resistance.

Anomalous aortic origin of a coronary artery (AAOCA) is the second most common cause of sudden cardiac death in young athletes. One of the hypothesized mechanisms of ischemia in these patients is the lateral compression of the anomalous artery with an intramural or interarterial course. The presence of a narrowing in the anomalous artery will cause physiologic changes in downstream resistance that should be included for computational assessment of possible clinical ramifications. In this study, we created different compression levels, i.e., proximal narrowing, in the intramural course of a representative patient model and calculated hyperemic stenosis resistance (HSR) as well as virtual fractional flow reserve (vFFR). Models also included the effect of the distal hyperemic microvascular resistance (HMR) on vFFR. Our results agreed with similar FFR studies indicating that FFR is increased with increasing HMR and that different compression levels could have similar FFR depending on the HMR. For example, vFFR at HSR: 1.0-1.3 and HMR: 2.30 mmHg/cm/s is 0.68 and close to vFFR at HSR: 0.6-0.7 and HMR: 1.6 mmHg/cm/s, which is 0.7. The current findings suggest that functional assessment of anomalous coronary arteries through FFR should consider the vascular resistance distal to the narrowing in addition to the impact of a proximal narrowing and provides computational approaches for implementation of these important considerations.

Mitral valve perforation, a hole-in-one for 3-dimensional echocardiography.

Mitral valve perforation is an uncommon aetiology of mitral regurgitation in the paediatric population. We present a case where 3-dimensional echocardiography assisted in the diagnosis of the source of mitral regurgitation and the surgical correlation.

Anomalous coronary arteries: what is known and what still remains to be learned?

PURPOSE OF REVIEW: To report what is known and unknown regarding coronary anomalies in children, particularly anomalous aortic origin of a coronary artery, efforts undertaken to answer several questions regarding evaluation and management of this challenging young population, and where the future is heading. RECENT FINDINGS: Patients with anomalous aortic origin of a coronary artery (AAOCA) present as an incidental finding at least half of the time, advanced imaging is essential to define anatomic characteristics of this lesion, assessment of myocardial perfusion with stress cardiac magnetic resonance imaging is feasible and contributes to risk stratification, certain patient populations require invasive assessment of coronary flow with measurement of fractional flow reserve, and surgical intervention can be safely performed through long-term data on impact to prevent sudden events is lacking. SUMMARY: Optimal risk stratification in AAOCA is yet to be defined, though substantial strides are being made with a standardized approach to the evaluation and management of these patients. Continued collaboration among centers and the scientific community will positively impact patients and families living with AAOCA.

Role of echocardiographic scoring systems in predicting successful biventricular versus univentricular palliation in neonates with critical aortic stenosis.

BACKGROUND: There are several published echo-derived scores to help predict successful biventricular versus univentricular palliation in neonates with critical aortic stenosis. This study aims to determine whether any published scoring system accurately predicted outcomes in these neonates. METHODS: Single centre, retrospective cohort study including neonates who underwent aortic valve intervention (surgical valvotomy or balloon valvuloplasty) with the intention of biventricular circulation. Primary outcome was survival with biventricular circulation at hospital discharge. Data from their initial neonatal echocardiogram were used to compute the following scores - Rhodes, CHSS 1, Discriminant, CHSS 2, and 2 V. RESULTS: Between 01/1999 and 12/2017, 68 neonates underwent aortic valve intervention at a median age of 4 days (range 1-29 days); 35 surgical valvotomy and 33 balloon valvuloplasty. Survival with biventricular circulation was maintained in 60/68 patients at hospital discharge. Of the remaining eight patients, three were converted to univentricular palliation, four died, and one underwent heart transplant prior to discharge. None of the binary score predictions of biventricular versus univentricular (using that score's proposed cut-offs) were significantly associated with the observed outcome in this cohort. A high percentage of those predicted to need univentricular palliation had successful biventricular repair: 89.4% by Rhodes, 79.3% by CHSS 1, 85.2% by Discriminant, and 66.7% by CHSS 2 score. The 2 V best predicted outcome and agreed with the local approach in most cases. CONCLUSION: This study highlights the limitations of and need for alternative scoring systems/cut-offs for consistently accurate echocardiographic prediction of early outcome in neonates with critical aortic stenosis.

Progressive aortic root dilatation in pediatric heart transplant recipients.

BACKGROUND: To determine prevalence, clinical implication, and risk factors for aortic root dilation (ARD) in pediatric heart transplant recipients. METHODS: Serial echocardiograms were reviewed in all pediatric heart transplant recipients from 1999 to 2014 to assess maximal systolic diameter at the aortic annulus, aortic sinus, aortic sino-tubular (ST) junction, and ascending aorta. ARD was defined by a sinus/annulus ratio >1.56, ST junction/annulus ratio >1.28, and/or ascending aorta/annulus ratio >1.35. RESULTS: A total of 147 subjects (53% male) were evaluated; 50% had congenital heart disease (CHD). Of the 74 with CHD, 38 had prior aortic arch reconstruction. The median age at transplant was 3 years (7 days-20.3 years) with a median duration of follow-up of 3.88 years (3 months-15 years). Prevalence of ARD significantly increased in the cohort from 15.6% at the initial echocardiogram to 49.6% at later follow-up (P<.0001). The median duration to development of ARD was 7.6 months. There were no significant differences in prevalence of ARD or days to maximum ratio based on the pretransplant diagnosis. Aortic regurgitation was very rare (7 with ≤mild) and did not correlate with ARD or require any interventions. CONCLUSION: During intermediate follow-up, ARD commonly develops in children post-heart transplant, and prevalence increases with time after transplant. Within 1 year after transplant, almost 50% had developed abnormalities in aortic root size that were not apparent at the initial posttransplant echocardiogram. Preexisting CHD or need for prior arch reconstruction did not increase the risk of ARD.

Anatomic Repair of Congenitally Corrected Transposition of the Great Arteries: Single-Center Intermediate-Term Experience.

We present our experience for patients who have undergone an anatomic repair (AR) for congenitally corrected transposition of the great arteries (CCTGA) at the Children's Hospital of Wisconsin. A retrospective chart review of patients who underwent AR for CCTGA from 2001 to 2015 was performed. The cohort consisted of 15 patients (74% male). Median age of anatomic repair was 15 months (range 4.5-45.6 months). Four patients had a bidirectional Glenn (BDG) prior to AR. At the time of AR,-9 (60%) underwent Senning/Rastelli procedure, 4 (26.6%) had double switch operation, and 2 (13.3%) underwent only Senning with VSD closure. Median duration of follow-up was 5.5 years (0.05-14 years). Reoperations prior to discharge included BDG, revision of pulmonary venous baffle, closure of residual VSD, and pacemaker placement. Late reoperations included left ventricular outflow tract obstruction repair, conduit replacement, melody valve placement, and pacemaker implantation. At their most recent follow-up, no patient had heart failure symptoms and only 1 had severely diminished function that improved with cardiac resynchronization therapy. Moderate mitral regurgitation was noted in 15% (2/13), and severe in 7% (1/13). Moderate tricuspid regurgitation was noted in 15% (2/13). One patient, 7% (1/13), developed moderate aortic insufficiency. There was a 100% survival at the time of the most recent follow-up. Patients with CCTGA who have undergone AR have excellent functional status and mid-term survival but reinterventions are common. Longer term studies are needed to determine both the extent and spectrum of reinterventions as well as long term survival.

Extracorporeal life support for a 5-week-old infant with idiopathic pulmonary hemosiderosis.

UNLABELLED: Idiopathic pulmonary hemosiderosis is a rare disease defined by the triad of iron deficiency anemia, hemoptysis, and diffuse pulmonary infiltrates on chest radiograph. Idiopathic pulmonary hemosiderosis is known to cause dyspnea and, in some cases, acute onset of massive pulmonary hemorrhage which is traditionally treated with conventional mechanical ventilation or high-frequency oscillation in conjunction with immunosuppressive therapy. In this case report, we describe a 5-week-old infant presenting with hemoptysis, massive pulmonary hemorrhage, and significant hypercapnic respiratory failure. The patient failed conventional ventilation but responded well to extracorporeal life support that was initiated early in his course. Idiopathic pulmonary hemosiderosis was suspected in light of his response to high-dose steroids and was confirmed by subsequent lung biopsies. CONCLUSION: Patients with severe pulmonary hemorrhage secondary to idiopathic pulmonary hemosiderosis can be safely supported with extracorporeal life support when conventional therapies have been exhausted.

Anomalous Coronary Arteries: A State-of-the-Art Approach.

Congenital coronary anomalies are not an infrequent occurrence and their clinical presentation typically occurs during early years, though may be manifested only in adulthood. In the setting of anomalous aortic origin of a coronary artery, this is particularly concerning as it inflicts sudden loss of healthy young lives. Risk stratification remains a challenge and so does the best management decision-making in these patients, particularly if asymptomatic. Standardized approach to evaluation and management, with careful data collection and collaboration among centers, will likely impact future outcomes in this patient population, thus allowing for exercise participation and healthier lives.

Wall motion assessment by feature tracking in pediatric patients with coronary anomalies undergoing dobutamine stress CMR.

Background: Left ventricular (LV) wall motion assessment is an important adjunct in addition to perfusion defects in assessing ischemic changes. This study aims to investigate the feasibility and utility of performing feature tracking (FT) in pediatric patients with coronary anomalies undergoing dobutamine stress CMR to assess wall motion abnormalities (WMA) and perfusion defects. Method: This is a retrospective study where 10 patients with an inducible first-pass perfusion (FPP) defect and 10 without were selected. Global LV circumferential strain/strain rate (GCS/GCSR) was measured at rest and at peak stress (systole and diastole) using a commercially available feature tracking software. Peak GCS and GCSR were compared to indexed wall motion score (WMSI) between groups with and without FPP defect and in subjects with and without WMA. Results: The median age of patients was 13.5 years (Q1, 11 years; Q3, 15 years). Five subjects had qualitatively WMA at peak stress. A moderate correlation of GCS with WMSI at peak stress (0.48, p = 0.026) and a significant difference between GCS at rest and stress in patients with no inducible WMA (p = 0.007) were seen. No significant difference was noted in GCS between rest and stress in patients with WMA (p = 0.13). There was a larger absolute GCS/GCSR at peak stress in subjects with no inducible FPP defect or WMA. Conclusion: Smaller absolute GCS and a lack of significant change in GCS at peak stress in those with inducible WMA or perfusion defect are suggestive of compromised LV deformation in subjects with inducible WMA. Given these findings, GCS derived from CMR-FT may be used to objectively assess WMA in pediatric patients undergoing stress CMR.

Evidence of cardiomyopathy associated with Marfan syndrome in children.

OBJECTIVE: Marfan syndrome (MFS)-associated cardiomyopathy, defined as ventricular dilation and dysfunction unexplained by volume loading, is not well defined in children. This study evaluated ventricular size and function in paediatric MFS using cardiac MRI (cMRI). METHODS: This retrospective cohort study examined patients with MFS <19 years old at first cMRI. Left ventricular (LV) ejection fraction (EF) <55% was considered abnormal, as were z-scores >2. Combined mitral and aortic regurgitation indexed to LV stroke volume <20% defined absent/mild volume load. Biventricular volumes and EF on serial cMRI studies were compared with normative paediatric cMRI values, with measures converted to z-scores as appropriate. Longitudinal changes in volumes and EF were evaluated by mixed linear regression. Associations between ventricular, aortic and mitral characteristics were evaluated. RESULTS: 58 patients (60% male) were evaluated. Median age at initial cMRI was 13.6 years (IQR 10.0-15.8 years). Among patients with absent/mild LV volume load at initial cMRI (n=44, 76%), indexed LV end-diastolic volume (EDV) was significantly increased above normative values (median z-score 1.8, IQR 0.6-3.5, p<0.0001) and LVEF was abnormal in 48% (21/44). In the absence of volume loading, mitral valve prolapse (MVP) was associated with larger ventricular volumes and lower LVEF. Among those with serial cMRIs, LVEF and EDV z-scores did not significantly change over a mean follow-up time between cMRI studies of 1.5 years. CONCLUSION: Ventricular dilation and reduced EF are common in children with MFS and occur with no/mild LV volume load, suggesting intrinsic cardiomyopathy. MVP may be associated with cardiomyopathy.

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.

Anomalous Coronary Arteries: A State-of-the-Art Approach.

Congenital coronary anomalies are not an infrequent occurrence and their clinical presentation typically occurs during early years, though may be manifested only in adulthood. In the setting of anomalous aortic origin of a coronary artery, this is particularly concerning as it inflicts sudden loss of healthy young lives. Risk stratification remains a challenge and so does the best management decision-making in these patients, particularly if asymptomatic. Standardized approach to evaluation and management, with careful data collection and collaboration among centers, will likely impact future outcomes in this patient population, thus allowing for exercise participation and healthier lives.

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.

Correlating decline in left ventricular ejection fraction and longitudinal strain in pediatric cancer patients.

PURPOSE: Left ventricular ejection fraction (LVEF) is routinely used to monitor cardiac function in cancer patients. Global longitudinal strain (GLS) detects subclinical myocardial dysfunction. There is no consensus on what constitutes a significant change in GLS in pediatric cancer patients. We aim to determine the change in GLS associated with a simultaneous decline in LVEF in pediatric cancer patients. METHODS: This is a retrospective longitudinal study of pediatric cancer patients treated with anthracyclines between October 2017 and November 2019. GLS was measured by 2-dimensional speckle tracking. The study outcome was a decline in LVEF, defined as a decrease in LVEF of ≥ 10% points from baseline or LVEF < 55%. We evaluated two echocardiograms per patient, one baseline, and one follow-up. The follow-up echocardiogram was either (1) the first study that met the outcome or (2) the last echocardiogram available in patients without the outcome. Statistical analyses included receiver operator characteristic curves and univariable and multivariable Cox proportional hazards regression. RESULTS: Out of 161 patients, 33 (20.5%) had a decline in LVEF within one year of follow-up. GLS reduction by ≥ 15% from baseline and follow-up GLS >-18% had sensitivities of 85% and 78%, respectively, and specificities of 86% and 83%, respectively, to detect LVEF decline. GLS reduction by ≥ 15% from baseline and follow-up GLS >-18% were independently associated with simultaneous LVEF decline [hazard ratio (95% confidence intervals): 16.71 (5.47-51.06), and 12.83 (4.62-35.63), respectively]. CONCLUSION: Monitoring GLS validates the decline in LVEF in pediatric cancer patients.

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.

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.

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.

Appropriateness of cardiovascular computed tomography and magnetic resonance imaging in patients with conotruncal defects.

BACKGROUND: To promote the rational use of cardiovascular imaging in patients with congenital heart disease, the American College of Cardiology developed Appropriate Use Criteria (AUC), but its clinical application and pre-release benchmarks have not been evaluated. We aimed to evaluate the appropriateness of indications for cardiovascular magnetic resonance (CMR) and cardiovascular computed tomography (CCT) in patients with conotruncal defects and to identify factors associated with maybe or rarely appropriate (M/R) indications. METHODS: Twelve centers each contributed a median of 147 studies performed prior to AUC publication (01/2020) on patients with conotruncal defects. To incorporate patient characteristics and center-level effects, a hierarchical generalized linear mixed model was used. RESULTS: Of the 1753 studies (80% CMR, and 20% CCT), 16% were rated M/R. Center M/R ranged from 4 to 39%. Infants accounted for 8.4% of studies. In multivariable analyses, patient- and study-level factors associated with M/R rating included: age <1 year (OR 1.90 [1.15-3.13]), truncus arteriosus (vs. tetralogy of Fallot, OR 2.55 [1.5-4.35]), and CCT (vs. CMR, OR 2.67 [1.87-3.83]). None of the provider- or center-level factors reached statistical significance in the multivariable model. CONCLUSIONS: Most CMRs and CCTs ordered for the follow-up care of patients with conotruncal defects were rated appropriate. However, there was significant center-level variation in appropriateness ratings. Younger age, CCT, and truncus arteriosus were independently associated with higher odds of M/R rating. These findings could inform future quality improvement initiatives and further exploration of factors resulting in center-level variation.