Cross-sectional echocardiography in hypoplastic left ventricle: Echocardiographic—angiographic—anatomic correlations

Summary Although M-mode echocardiography has become a valuable tool in the noninvasive diagnosis of hypoplastic left ventricle (HLV), it may not resolve all diagnostic uncertainty. This study compares the findings of M-mode echocardiography, cross-sectional echocardiography, and autopsy in a group of 20 infants with HLV. M-mode echocardiograms alone were obtained in eight infants; five of these children underwent cardiac catheterization, and six underwent autopsy. Cross-sectional echocardiograms were obtained in the remaining 12 infants; two of these underwent cardiac catheterization, and all 12 underwent autopsy. Cross-sectional examinations were performed with either a high-resolution mechanical sector scanner or a sequentially scanning linear array. Short-axis views were used for left ventricular size and shape and for aortic root, pulmonary artery, and ductus size; suprasternal notch views were used for imaging the aortic arch and subxiphoid views for the atrial cavities. In all 12 infants the findings from cross-sectional echocardiography closely matched those of autopsy with respect to degree of hypoplasia of the mitral valve, the left ventricular cavity, and the left ventricular outflow tract. If the diameter of a valve orifice exceeded 3 mm at autopsy, patency of the valve could be diagnosed from the cross-sectional echocardiogram. The findings when M-mode echocardiograms alone were done less closely matched the autopsy findings, and in five of the eight cardiac catheterization was judged necessary to resolve remaining diagnostic uncertainty. This study found that cross-sectional echocardiography provided an accurate noninvasive diagnosis of the spectrum of anatomy found in HLV and had fewer pitfalls than M-mode echocardiography.     

Stent Dilatation of a Right Ventricle to Pulmonary Artery Conduit in a Postoperative Patient with Hypoplastic Left Heart Syndrome

A 10‐day‐old child with hypoplastic left heart syndrome (HLHS) underwent first‐stage palliation for HLHS, Norwood procedure with a Sano modification, i.e., placement of a right ventricular to pulmonary artery (RV‐PA) conduit. The patient developed progressively worsening systemic oxygen desaturation in the immediate postoperative period. Stenosis of the proximal RV‐PA conduit was diagnosed by echocardiography. In the catheterization laboratory stent placement in the conduit was performed. This resulted in increased systemic oxygen saturation. The patient was eventually discharged from the hospital with adequate oxygen saturations.     

Trismus-pseudocamptodactyly syndrome with bilateral hypoplastic mandibular condyles and shallow mandibular fossa: A case report

Trismus-pseudocamptodactyly syndrome (TPS) (OMIM#158300), also known as Hecht syndrome, is a rare autosomal dominant distal arthrogryposis. Bilateral hyperplasia of the coronoid processes has been reported to cause trismus. In this study, we report a case of TPS definitively diagnosed on the basis of clinical signs in a patient who had bilateral hypoplastic mandibular condyles and shallow mandibular fossa; TPS in such patients have never been reported in the literature. On the basis of the present case, we propose that a hypoplastic mandibular condyle and shallow mandibular fossa are also clinical features of TPS.     

Surgical strategy for pulmonary atresia with intact ventricular septum: initial management and definitive surgery

Pulmonary atresia with intact ventricular septum is difficult to manage, and the surgical procedures are associated with high mortality and morbidity. The lesion is morphologically heterogeneous, with varying degrees of right ventricular and tricuspid valve hypoplasia. Aberrations of the coronary circulation are common. A single approach is impractical because the wide spectrum of right heart morphology makes a uniform surgical approach impossible. Anatomical criteria, such as the degree of tricuspid valve or right ventricular hypoplasia or whether a right ventricular infundibulum is present, have been used to assign the infants to single-ventricular or biventricular repair tracks. If the patient is considered a candidate for biventricular repair, right ventricular decompression, either alone or combined with a systemic-pulmonary artery shunt, is performed, whereas only a systemic-pulmonary artery shunt is performed in a candidate for single-ventricular repair. Several authors reported that the Z-value of the tricuspid valve diameter could be a guide to the initial procedure; however, poor interobserver reproducibility and wide normal ranges are serious limitations. Definitive operations, including biventricular repair, one-and-a-half ventricular repair, or Fontan-type operation, are performed to eliminate cyanosis. The most important problem when planning a strategy for a definitive repair is the fact that right ventricular growth and its contribution to pulmonary flow is difficult to predict before the operation. The management protocol should be determined by the precisely estimated morphology of the right ventricle and tricuspid valve, and the adequacy of the protocol should be analyzed based on surgical outcomes. This review was submitted at the invitation of the editorial committee.     

Edge-to-edge tricuspid valve repair in hypoplastic left heart syndrome

Tricuspid regurgitation (TR) is known to be a risk factor for mortality in the surgical management of patients with hypoplastic left heart syndrome (HLHS). Concomitant repair for TR should be considered when the TR is moderate to severe to achieve successful Fontan completion. The present case was a 20-month-old girl who was diagnosed with HLHS (mitral atresia and aortic atresia). She underwent a Norwood procedure as the first palliation followed by a Glenn procedure. After that, she gradually developed TR, which progressed to a severe state at the time of the Fontan procedure. An edge-to-edge tricuspid valve repair, in which the anterior and septal leaflets were sutured together, was performed simultaneously with the extracardiac Fontan procedure. Discharge echocardiography revealed that the degree of TR was less than mild. The technique is simple, not time-consuming, and may be an effective adjunct for successful completion of the Fontan procedure in these patients.     

Acute Interventions for Stenosed Right Ventricle‐Pulmonary Artery Conduit Following the Right‐Sided Modification of Norwood‐Sano Procedure

Introduction. The Norwood stage 1 procedure was modified by Sano with right ventricle‐pulmonary artery (RV–PA) conduit replacing BT shunt. In our institution, this has been further modified by placing the conduit from the RV outflow tract to the right side of the neo‐aorta. Patients and Methods. Between April 2002 and October 2008, 227 modified Norwood procedures were performed. Eighteen had the Sano modification with the conduit to the left of the neo‐aorta whereas 209 had the right‐sided modification, which is the study population. A total of 18 (8.6%) patients presented with cyanosis due to conduit stenosis with median age 4 months and median weight 6.3 kg. Results. Twelve patients underwent transcatheter stent placement in stenosed RV–PA conduit. A total of 16 coronary stents were implanted in 12 patients with 4 patients each receiving 2 stents. The mean saturations increased from 60% to 74%. There was one late mortality which was non‐procedure related. Five patients treated with surgical take down of the RV–PA conduit and creation of a cavo‐pulmonary shunt, whilst one patient had replacement of RV–PA conduit. There were no early postoperative deaths. The mean saturations improved from 54% to 75%. Conclusions. The RV–PA conduit stenosis is a life‐threatening complication after the modified Norwood Stage I procedure. This may require urgent surgery to replace the conduit or to perform a cavo‐pulmonary shunt but as an alternative, transcatheter stent placement can be used with equal effectiveness and with a low risk of complications. The catheter approach is less invasive and the results show that it is an excellent option to relieve the stenosis even in the right‐sided RV–PA conduit.