Case report: duct dependency in hypoplastic left heart complex can be reversible without surgery

We describe an infant with duct-dependent hypoplastic left heart complex with moderate hypoplasia of the left ventricle and aortic arch who was not operated due to resource limitations. The left-sided structures grew remarkably due to favourable loading condition changes of the left ventricle, allowing weaning from prostaglandin at the age of 3 months and discharging the patient without intervention.

Growth of hypoplastic mitral valves in hypoplastic left heart complex and similar constellations after anatomical left superior vena cava correction

OBJECTIVES Left superior vena cava (LSVC)-related obstruction of mitral inflow is a rare finding in patients with complex cardiac anomalies like hypoplastic left heart complex. We report our experience by establishing a left superior to right superior caval vein continuity (innominate vein creation by direct LSVC–right superior vena cava end-to-side-anastomosis), and coronary sinus unroofing if indicated for LSVC-related mitral inflow obstruction. METHODS Nineteen patients (median age: 1.0 ± 0.3 years; range: 7 days–4.8 years) underwent anatomical correction of LSVC without the use of foreign material in conjunction with repair or palliation of congenital anomalies in a single centre between April 2015 and November 2019. Indications for the procedure were LSVC-related obstruction of left ventricular inflow due to a dilated coronary sinus. Additional procedures included mitral (n = 7) or atrioventricular (n = 3) valve surgery, right ventricular to pulmonary artery conduit (n = 3), first stage palliation (n = 3) or biventricular repair (n = 5) of hypoplastic left heart complex. Three patients needed secondary mitral valve replacement (n = 3). RESULTS All LSVC or coronary sinus-related obstructions were effectively relieved. No patient died early, 2 patients died late after the procedure. One patient needed stenting of the superior vena cava below the unobstructed cephalad vein anastomosis at the former right superior vena cava-cannulation-site. Follow-up was complete and demonstrated an 89.5% survival after 2.5 ± 0.4 years. Innominate vein patency was 100% documented by echocardiography (n = 19), cardiac catheterization (n = 6) or both. Mean mitral valve z-scores before the operation were −1.7 ± 0.2 (range −3.8 to 0.3) and increased to 0.7 ± 0.2 (range −0.7 to 1.9) after LSVC repair. CONCLUSIONS Anatomical correction by surgical creation of an innominate vein is an effective method to relieve LSVC-related obstructions and promotes mitral valvar growth. Mitral ring sizes were at least normalized after surgery at the time of discharge. Further prospective follow-up studies to evaluate the growth potential of left-sided heart structures by reporting cardiac z-scores are needed to evaluate the true impact of coronary sinus unroofing.

Norwood procedure with right ventricle to pulmonary artery conduit: a single-centre 20-year experience

OBJECTIVES The aim of this study was to evaluate the long-term outcomes of the Norwood procedure with right ventricle–pulmonary artery (RV–PA) conduit for hypoplastic left heart complex. METHODS A retrospective observational study was performed in 136 patients with hypoplastic left heart complex who underwent a Norwood procedure with RV–PA conduit between 1998 and 2017. The probabilities of survival, reintervention and Fontan completion were analysed. RESULTS Stage 1 survival was 91.9% (125/136). Reintervention for PA stenosis was needed for 22% and 30% at stages 2 and 3, respectively, while 15% underwent reintervention for aortic arch recoarctation. Among 106 bidirectional Glenn survivors, 93 (68% of the total number of patients) had a Fontan completion, while 4 were not considered to be Fontan candidates. Risk factors for overall mortality included weighing <2.5 kg at the time of the Norwood procedure, intact atrium septum, total anomalous pulmonary vein connection and more than mild atrioventricular regurgitation at the time of the Norwood procedure. Overall survival was 80.9%, 72.3% and 62.8% at 1, 5 and 20 years, respectively. CONCLUSIONS Probabilities of survival and Fontan completion were acceptable under the current surgical strategy incorporating RV–PA Norwood procedure as the first palliation. Incorporating a strategy to maintain PA growth and ventricular function through the staged repair is of prime importance. Further studies are necessary to observe changes in atrioventricular regurgitation as well as in right ventricular function, in patients who require atrioventricular valve interventions during the staged Fontan completion.

Follow-up after biventricular repair of the hypoplastic left heart complex

OBJECTIVES In hypoplastic left heart complex patients, biventricular repair is preferred over staged-single ventricle palliation; however, there are too few studies to support either strategy. Therefore, we retrospectively characterized our patient cohort with hypoplastic left heart complex after biventricular repair to measure left-sided heart structures and assess our treatment strategy. METHODS Patients with hypoplastic left heart complex who had biventricular repair between 2004 and 2018 were retrospectively reviewed. Operative results were evaluated and echocardiographic mitral valve (MV) and aortic valve (AoV) dimensions, left ventricular length and left ventricular internal diastolic diameter (LVIDd) were measured preoperatively and during follow-up after 0.5, 1, 3, 5 and 10 years. RESULTS In 32 patients, the median age at surgery was 10 (interquartile range 5.0) days. The median follow-up was 6.19 (interquartile range 6.04) years. During the 10-year follow-up, the mean Z-scores increased from −2.82 to −1.49 and from −2.29 to 0.62 for MV and AoV, respectively. Analysis of variance results with post hoc paired t-tests showed that growth of left-sided heart structures was accelerated in the first year after repair, but was not equal, with the MV lagging behind the AoV (P = 0.033), resulting in significantly smaller MV Z-scores compared with AoV Z-scores at 10-year follow-up (P < 0.001). There were 2 (6%) early deaths. The major adverse events occurred in 4 (13%) patients. The surgical or catheter-based reintervention was required in 14 (44%) patients. CONCLUSIONS The growth rate of heart structures was most prominent during the first year after biventricular repair with lower growth rate of the MV compared with the AoV.

Comparison of self-expandable and balloon-expanding stents for hybrid ductal stenting in hypoplastic left heart complex

ObjectivesWe aimed to compare the procedural and mid-term performance of a specifically designed self-expanding stent with balloon-expandable stents in patients undergoing hybrid palliation for hypoplastic left heart syndrome and its variants.BackgroundThe lack of specifically designed stents has led to off-label use of coronary, biliary, or peripheral stents in the neonatal ductus arteriosus. Recently, a self-expanding stent, specifically designed for use in hypoplastic left heart syndrome, has become available.MethodsWe carried out a retrospective cohort comparison of 69 neonates who underwent hybrid ductal stenting with balloon-expandable and self-expanding stents from December, 2005 to July, 2014.ResultsIn total, 43 balloon-expandable stents were implanted in 41 neonates and more recently 47 self-expanding stents in 28 neonates. In the balloon-expandable stents group, stent-related complications occurred in nine patients (22%), compared with one patient in the self-expanding stent group (4%). During follow-up, percutaneous re-intervention related to the ductal stent was performed in five patients (17%) in the balloon-expandable stent group and seven patients (28%) in self-expanding stents group.ConclusionsHybrid ductal stenting with self-expanding stents produced favourable results when compared with the results obtained with balloon-expandable stents. Immediate additional interventions and follow-up re-interventions were similar in both groups with complications more common in those with balloon-expandable stents.