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Aims The aortic valve (AV) neocuspidization (Ozaki procedure) is a novel surgical technique for AV disease that preserves the natural motion and cardiodynamics of the aortic root. In this study, we sought to evaluate, by 4D-flow magnetic resonance imaging, the aortic blood flow characteristics after AV neocuspidization in paediatric patients. Methods and results Aortic root and ascending aorta haemodynamics were evaluated in a population of patients treated with the Ozaki procedure; results were compared with those of a group of patients operated with the Ross technique. Cardiovascular magnetic resonance studies were performed at 1.5 T using a 4D flow-sensitive sequence acquired with retrospective electrocardiogram-gating and respiratory navigator. Post-processing of 4D-flow analysis was performed to calculate flow eccentricity and wall shear stress. Twenty children were included in this study, 10 after Ozaki and 10 after Ross procedure. Median age at surgery was 10.7 years (range 3.9–16.5 years). No significant differences were observed in wall shear stress values measured at the level of the proximal ascending aorta between the two groups. The analysis of flow patterns showed no clear association between eccentric flow and the procedure performed. The Ozaki group showed just a slightly increased transvalvular maximum velocity. Conclusion Proximal aorta flow dynamics of children treated with the Ozaki and the Ross procedure are comparable. Similarly to the Ross, Ozaki technique restores a physiological laminar flow pattern in the short-term follow-up, with the advantage of not inducing a bivalvular disease, although further studies are warranted to evaluate its long-term results. [ABSTRACT FROM AUTHOR]

Aim: Young patients with operated complex congenital heart defects (CHD) often develop sinus node dysfunction (SND) requiring permanent pacing with rate-responsive function. Activity-driven sensors cannot account for nonmovement stress and cannot modulate heart rate physiologically. Closed Loop Stimulation (CLS, Biotronik, Berlin, Germany) is a physiological rate-responsive pacemaker based on the indirect measure of ventricular contractility. No data are available on the effects of such pacing strategy in young patients.Methods: We report a series of nine patients with CHD and SND who underwent single-chamber CLS-atrial pacing with endocardial or epicardial lead. During the first 30 days, the pacemaker was programmed in AAI pacing mode and then was switched to CLS-atrial pacing mode. An in-hospital control was scheduled 1–2 months later to evaluate the CLS response to neurovegetative stresses (i.e.,nonmovement stress [Stroop color test, handgrip] and exercise stress test) and Holter monitor. CLS pacing was compared with rate-responsive accelerometer-driven pacing (AAIR).Results: At telemetric interrogation, CLS pacing showed a more physiological pattern of 24-h heart rate trends than accelerometer sensors. The data obtained during nonmovement/exercisestress demonstrated a physiological increase in the pacing rate with CLS, in synergy with spontaneous events. The accelerometer sensor histogram, during nonmovement stress, showed a “non-response" behavior (only lower rate events), and during exercise test showed most events in lower rate range. Holter monitoring showed increase of average and maximum heart rate compared with AAIR.Conclusion: In young CHD patients, endocardial/epicardial CLS-atrial pacing demonstrated a physiological response of heart rate to neurovegetative and physical stresses. [ABSTRACT FROM AUTHOR]

Objective: Congenital mitral ring is a rare subtype of congenital mitral stenosis. Our objective is to review the anatomic findings and surgical results of this lesion and to identify early predictors of outcome. Methods: Clinical reports, echocardiographic studies, cardiac catheterizations, surgical reports, and follow-up data of all patients with mitral ring diagnosed at the Bambino Gesù Hospital were retrospectively reviewed. Results: Between January of 1987 and June of 2007, a mitral ring was diagnosed in 25 patients (13 male) with a mean age at diagnosis of 36 months. The ring was identified in a single neonate but seemed to develop and progress during infancy. All but 1 patient had associated cardiac anomalies. We identified 2 distinct subtypes: “intramitral ring” in 18 of 25 patients (72%), associated with complex valve pathology and a worse outcome, and “supramitral ring” in 7 of 25 patients (18%), in whom the mitral apparatus was usually normal and the outcome was better. The ring was surgically removed in 13 of 25 patients (52%) (mean Doppler gradient 15 ± 4 mm Hg). The gradient decreased in 9 of 13 patients (mean diastolic transmitral gradient ≤ 5 mm Hg) and has remained stable during a mean follow-up of 90 months. The mean diastolic gradient remained high (>8 mm Hg) in the other 4 patients, all with intramitral ring. All 4 patients underwent repeat mitral valvuloplasty. There were no operative or late deaths. Conclusion: Two types of congenital mitral ring, with diverse valve pathology and outcome, were identified. Rarely seen in neonates, the ring develops and often progresses during infancy. Recognition is important because surgical results are better than for other forms of congenital mitral stenosis. [Copyright &y& Elsevier]

OBJECTIVES To identify factors associated with the surgical outcome in patients undergoing right ventricular outflow tract reconstruction (RVOTR) using decellularized tissue-engineered pulmonary valve conduits (TEPVc) and to study their safety and longevity. METHODS From April 2006 to April 2010, 93 patients underwent either palliative or corrective RVOTR using Matrix P (37) and Matrix P Plus (56) xenogenic decellularized TEPVc (size range 11–27 mm). Median age and weight at operation were 20 (0.16–290) months and 10.15 (2.65–86) kg respectively. Primary and redo surgery occurred in 40 and 60% of cases, respectively. Eighty-eight patients (94.6%) received conduit implantation in the framework of corrective surgery, whereas in 5 (5.4%) a palliative procedure was undertaken. Follow-up was complete in 91% of patients, with a median duration of 12 months (range: 2 days–51 months). Data analysis included diagnosis, type of surgery (palliative vs. corrective) and age at surgery. Predetermined primary outcomes were represented by conduit failure or dysfunction. RESULTS Two patients with Matrix P and two with Matrix P Plus died in the early post-operatively phase (4.3%). None of the deaths were conduit-related. One patient died at conduit replacement. Thirty-three patients (35.5%) experienced conduit failure whereas conduit dysfunction occurred in 27 patients (29%). Two-year freedom from conduit failure and dysfunction was 60.2% (95% CI: 50.1–69.6) and 77.4% (95% CI: 67.9–84.7), respectively. Reasons for failure were conduit stenosis in 20 cases (61%), pseudoaneurysm in 3 (9%), conduit dilatation (>50% of original diameter) in 2 (6%), stenosis of distal anastomosis involving pulmonary bifurcation in 6 (18%) and allograft dissection in 2 (6%). Histological examination showed inflammatory giant-type cells in the presence of a poor autologous cell seeding in all explanted specimens. Univariate and multivariate analyses showed an association between age at surgery ≤1 year and conduit dysfunction (adjusted HR: 2.29; 95% CI: 1.01–5.20, P = 0.04). CONCLUSIONS Compared with the other conduit for RVOTR Matrix conduits showed a high incidence of failure. Our results suggest that the use of Matrix conduits for RVOTR should be considered with caution. [ABSTRACT FROM AUTHOR]

Summary: The population of neonates and children with congenital heart defects presents about a 30% prevalence of associated genetic syndrome or additional extracardiac anomalies and may show an increased risk of death or major complication at cardiac surgery. Since a well-defined pattern of combined cardiac and extracardiac anomalies may be found in relation to specific genetic defects, correct understanding of the genetic issues may help improving diagnosis, surgical approach and final outcome of these patients. Hereby we review the medical and surgical issues correlated to the genetic asset in patients with congenital heart defects and genetic syndromes, including trisomy 21, deletion 22q11, Noonan/LEOPARD, Turner, Marfan and Williams syndromes. Recognition of specific surgical risk factors can lead to the preparation of specific diagnostic and perioperative protocols in order to reduce operative mortality and morbidity. [Copyright &y& Elsevier]

Objective: Evaluation of incremental risk factors for early mortality in children undergoing orthotopic heart transplantation (OHT) for failing single ventricle physiology. Methods: Between 1988 and 2002, 25 patients (mean age 9.3±7.1 years) underwent OHT for complex congenital heart disease (CHD) with a functional right (15 patients) or left (10 patients) single ventricle. Palliative staging towards Fontan completion had been previously accomplished in 22 patients (88%). Transition to OHT occurred from a shunt stage in 10, a bi-directional cavopulmonary anastomosis (BDG) stage in nine, and after Fontan failure in six patients. Results: Thirty-day survival was 68.0±9.3% with no additional mortality up to 14.1 years. OHT following BDG staging exhibited 100% long-term survival, as opposed to 66.7±15.7% for OHT after systemic-to-pulmonary shunt, and 33.3±19.2% for OHT following failing Fontan (p=0.032). Regression logistic modelling indicated failing Fontan circulation as predictor of higher mortality after OHT (p=0.041). Reintervention was necessary in four patients 40±11 months after OHT to address residual superior vena cava (two) and isthmic (two) stenosis. Overall freedom from reintervention was 88.3±8.1% at 5 years. Conclusions: OHT for structural CHD with single ventricle physiology entails substantial early mortality while BDG enables the best transition to heart transplant. OHT should be considered in the decision-making process as an alternative to Fontan completion in high-risk candidates, since rescue-OHT after failing Fontan seems unwarranted. [Copyright &y& Elsevier]