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Aims Patients with repaired tetralogy of Fallot (rTOF) have an increased risk of ventricular tachycardia (VT), with slow conducting anatomical isthmus (SCAI) 3 as dominant VT substrate. In patients with right bundle branch block (RBBB), SCAI 3 leads to local activation delay with a shift of terminal RV activation towards the lateral RV outflow tract which may be detected by terminal QRS vector changes on sinus rhythm electrocardiogram (ECG). Methods and results Consecutive rTOF patients aged ≥16 years with RBBB who underwent electroanatomical mapping at our institution between 2017–2022 and 2010–2016 comprised the derivation and validation cohort, respectively. Forty-six patients were included in the derivation cohort (aged 40±15 years, QRS duration 165±23 ms). Among patients with SCAI 3 (n = 31, 67%), 17 (55%) had an R″ in V1, 18 (58%) had a negative terminal QRS portion (NTP) ≥80 ms in aVF, and 12 (39%) had both ECG characteristics, compared to only 1 (7%), 1 (7%), and 0 patient without SCAI, respectively. Combining R″ in V1 and/or NTP ≥80 ms in aVF into a diagnostic algorithm resulted in a sensitivity of 74% and specificity of 87% in detecting SCAI 3. The inter-observer agreement for the diagnostic algorithm was 0.875. In the validation cohort [ n = 33, 18 (55%) with SCAI 3], the diagnostic algorithm had a sensitivity of 83% and specificity of 80% for identifying SCAI 3. Conclusion A sinus rhythm ECG-based algorithm including R″ in V1 and/or NTP ≥80 ms in aVF can identify rTOF patients with a SCAI 3 and may contribute to non-invasive risk stratification for VT. [ABSTRACT FROM AUTHOR]

Open in new tab Download slide OBJECTIVES Coronary transfer remains the most crucial part of the arterial switch operation (ASO); yet, certain coronary anatomies prohibit the use of button or trap-door transfer techniques. In the rare setting of 'non-separable' single sinus coronary arteries with intramural course, the modified Yacoub aortocoronary flap technique is a viable option. The aim of this study is to describe this operative technique and review its early- and mid-term outcomes. METHODS This retrospective analysis included all cases with 'non-separable' single sinus coronary arteries with intramural course where the modified Yacoub aortocoronary flap technique served as a bail-out option. RESULTS Of 516 patients who underwent ASO at our institution between January 1977 and April 2022, 14 underwent the modified Yacoub aortocoronary flap technique. The median age at ASO was 10 (interquartile range 7–19) days. Hospital mortality occurred in 3 patients (21.4%), all being related to coronary complications. All hospital survivors were still alive at a median of 9.1 (interquartile range 4.2–18.3) years after the ASO. None of them developed complaints of ischaemia, ventricular arrhythmias, ventricular dysfunction or exercise intolerance. Surveillance computed tomography angiography showed stable aortocoronary relationships free from stenosis, compression and kinking. No reoperations for coronary artery problems and/or neoaortic valve or root problems were needed. CONCLUSIONS Although close monitoring of early coronary events seems crucial to prevent perioperative mortality, the modified Yacoub aortocoronary flap technique may serve as a viable bail-out option in patients with 'non-separable' single sinus coronary anatomy with intramural course, with excellent results among hospital survivors. [ABSTRACT FROM AUTHOR]

Aim: To map somatic growth patterns throughout Fontan palliation and summarise evidence on its key modifiers. Methods: Databases were searched for relevant articles published from January 2000 to December 2021. Height and weight z scores at each time point (birth, Glenn procedure, Fontan procedure and >5 years after Fontan completion) were pooled using a random effects meta‐analysis. A random effects meta‐regression model was fitted to model the trend in z scores over time. Results: Nineteen studies fulfilled eligibility criteria, yielding a total of 2006 participants. The z scores for height and weight were markedly reduced from birth to the interstage period, but recovered by about 50% following the Glenn procedure. At >10 years after the Fontan procedure, the z scores for weight seemed to normalise despite persistent lower height, resulting in increased body mass index. The review revealed a number of modifiers of somatic growth, including aggressive nutritional management, timing of Glenn/Fontan, prompt resolution of complications and obesity prevention programmes in adolescence and adulthood. Conclusion: This review mapped the somatic growth of single ventricle patients and summarised key modifiers that may be amendable to improvement. These data provide guidance on strategies to further optimise somatic growth in this population and may serve as a benchmark for clinical follow‐up. [ABSTRACT FROM AUTHOR]

Open in new tab Download slide OBJECTIVES To date, it is not known if 16–20-mm extracardiac conduits are outgrown during somatic growth from childhood to adolescence. This study aims to determine total cavopulmonary connection (TCPC) haemodynamics in adolescent Fontan patients at rest and during simulated exercise and to assess the relationship between conduit size and haemodynamics. METHODS Patient-specific, magnetic resonance imaging-based computational fluid dynamic models of the TCPC were performed in 51 extracardiac Fontan patients with 16–20-mm conduits. Power loss, pressure gradient and normalized resistance were quantified in rest and during simulated exercise. The cross-sectional area (CSA) (mean and minimum) of the vessels of the TCPC was determined and normalized for flow rate (mm2/l/min). Peak (predicted) oxygen uptake was assessed. RESULTS The median age was 16.2 years (Q1–Q3 14.0–18.2). The normalized mean conduit CSA was 35–73% smaller compared to the inferior and superior vena cava, hepatic veins and left/right pulmonary artery (all P  < 0.001). The median TCPC pressure gradient was 0.7 mmHg (Q1–Q3 0.5–0.8) and 2.0 (Q1–Q3 1.4–2.6) during rest and simulated exercise, respectively. A moderate–strong inverse non-linear relationship was present between normalized mean conduit CSA and TCPC haemodynamics in rest and exercise. TCPC pressure gradients of ≥1.0 at rest and ≥3.0 mmHg during simulated exercise were observed in patients with a conduit CSA ≤ 45 mm2/l/min and favourable haemodynamics (<1 mmHg during both rest and exercise) in conduits ≥125 mm2/l/min. Normalized TCPC resistance correlated with (predicted) peak oxygen uptake. CONCLUSIONS Extracardiac conduits of 16–20 mm have become relatively undersized in most adolescent Fontan patients leading to suboptimal haemodynamics. [ABSTRACT FROM AUTHOR]

Background Coronary anomalies are present in one-third of all patients with transposition of the great arteries (TGA) and have been associated with increased risk of adverse outcomes after the arterial switch operation. Therefore, knowledge about coronary anatomy remains key. Case summary A 5-day-old girl with prenatal diagnosis of Taussig–Bing anomaly (double outlet right ventricle with TGA and large subpulmonary ventricular septal defect) along with aortic arch hypoplasia and coarctation of the aorta underwent the arterial switch operation with closure of the ventricular septal defect and aortic arch repair. On preoperative echocardiography, the right (R) and left coronary artery (LCx) connected both to aortic sinus 1, suggesting 1RLCx coronary anatomy according to the Leiden Convention coronary coding system. However, intraoperative inspection led to a reclassification of the coronary anatomy: the right coronary artery and left anterior descending coronary artery connected to aortic sinus 1 (1RL) as had been observed on echocardiography, but—remarkably—the circumflex coronary artery (Cx) connected to the posterior sinus of the pulmonary trunk. As a consequence, cardioplegia was administered into both the aortic and pulmonary roots, and the circumflex coronary artery could stay in its native position without having to be transferred during the arterial switch operation. Discussion Various disruptions during embryological development can lead to unusual coronary anatomy in TGA patients. While anomalous connection of a coronary artery to the pulmonary trunk remains exceedingly rare, care should be taken to identify this pattern when present as failure to do so may result in adverse outcomes. [ABSTRACT FROM AUTHOR]

Open in new tab Download slide OBJECTIVES Adequacy of 16–20mm extracardiac conduits for adolescent Fontan patients remains unknown. This study aims to evaluate conduit adequacy using the inferior vena cava (IVC)–conduit velocity mismatch factor along the respiratory cycle. METHODS Real-time 2D flow MRI was prospectively acquired in 50 extracardiac (16–20mm conduits) Fontan patients (mean age 16.9 ± 4.5 years) at the subhepatic IVC, conduit and superior vena cava. Hepatic venous flow was determined by subtracting IVC flow from conduit flow. The cross-sectional area (CSA) was reported for each vessel. Mean flow and velocity was calculated during the average respiratory cycle, inspiration and expiration. The IVC–conduit velocity mismatch factor was determined as follows: V conduit/ V IVC, where V is the mean velocity. RESULTS Median conduit CSA and IVC CSA were 221 mm2 (Q1–Q3 201–255) and 244 mm2 (Q1–Q3 203–265), respectively. From the IVC towards the conduit, flow rates increased significantly due to the entry of hepatic venous flow (IVC 1.9, Q1–Q3 1.5–2.2) versus conduit (3.3, Q1–Q3 2.5–4.0 l/min, P < 0.001). Consequently, mean velocity significantly increased (IVC 12 (Q1–Q3 11–14 cm/s) versus conduit 25 (Q1–Q3 17–31 cm/s), P < 0.001), resulting in a median IVC–conduit velocity mismatch of 1.8 (Q1–Q3 1.5–2.4), further augmenting during inspiration (median 2.3, Q1–Q3 1.8–3.0). IVC–conduit mismatch was inversely related to measured conduit size and positively correlated with conduit flow. The normalized IVC–conduit velocity mismatch factor during expiration and the entire respiratory cycle correlated with peak VO2 (r = –0.37, P = 0.014 and r = –0.31, P = 0.04, respectively). CONCLUSIONS Important blood flow accelerations are observed from the IVC towards the conduit in adolescent Fontan patients, which is related to peak VO2. This study, therefore, raises concerns that implanted 16–20mm conduits have become undersized for older Fontan patients and future studies should clarify its effect on long-term outcome. [ABSTRACT FROM AUTHOR]