Significance of low peak Doppler velocity in the proximal sano conduit in hypoplastic left heart syndrome.

BACKGROUND: The Sano modification of the Norwood operation is a well-established first step palliation for hypoplastic left heart syndrome (HLHS). Theoretically, the first point of resistance to pulmonary flow should be in the proximal Sano, generating high Doppler flow velocity. Paradoxically, however, some patients have low gradients in the proximal Sano conduit. The objective of this study was to determine the hemodynamic and anatomic significance of low proximal Sano Doppler flow velocity and its clinical implications. METHODS: Doppler-derived peak gradients in the proximal Sano conduits were measured in HLHS patients after Norwood-Sano surgery over a 4-year period and confirmed by cardiac catheterization within 2 to 4 weeks. Clinical outcomes of patients with proximal Sano gradients of 30 mm Hg or less (group 1) were compared with patients whose gradient was greater than 30 mm Hg (group 2). RESULTS: Of the 53 patients, 21 (40%) belonged to group 1. Patients in group 1 had smaller ostial right and left pulmonary artery (PA) diameter (3.2 ± 1.2 mm versus 4.5 ± 1.8 mm, p = 0.03; and 3.4 ± 1.2 mm versus 5.6 ± 2.1 mm, p = 0.01) when compared with patients in group 2. Patients (7 of 10) who needed either balloon angioplasty of a distal Sano or proximal branch PA were from group 1 (p = 0.01). Patients in group 1 had higher rates of unintended PA interventions (33% versus 9%) and complications (48% versus 16%) compared with group 2. CONCLUSIONS: Low peak Doppler flow velocity in the proximal Sano correlates with the presence of either distal Sano stenosis or proximal branch PA stenosis. These patients require close follow-up in the interstage period and may need earlier intervention.

Shunt reintervention and time-related events after Norwood operation: impact of shunt strategy.

BACKGROUND: The use of right ventricle-to-pulmonary artery shunt (RV-PA) is thought to improve postoperative hemodynamics in hypoplastic left heart syndrome (HLHS). Proximal shunt obstruction often prompts early reintervention. Description of our technique and analysis of outcomes after Norwood operation using RV-PA shunt (NRVPA) was undertaken. METHODS: Between January 2005 and June 2009, 100 consecutive neonates with HLHS underwent stage-1 palliation (S1P). Sixty-five had NRVPA. From 56 survivors, 52 (86. 2%) reached pre-Glenn cardiac catheterization. The RV-PA shunt was constructed using nonringed polytetrafluoroethylene with reversed beveling and hood augmentation of its anterior wall. The PA size, Nakata index, pulmonary to systemic blood flow ratio, and any pre-Glenn intervention were studied. The RV function and NRVPA diastolic reversal flow were assessed. RESULTS: Mean age and weight at S1P were 6. 6 ± 3. 5 days and 3. 21 ± 0. 57 kg, respectively. No shunt reversal flow to RV was noted the first 48 hours after S1P by echocardiogram. No patient had shunt revision after hospital discharge from S1P. Mean age and weight at stage-2 palliation were 14. 9 ± 5. 1weeks and 5. 4 ± 2. 1 kg, respectively. No patient had proximal shunt stenosis. Six patients with distal shunt stenosis and associated central PA hypoplasia (32% ± 17% PA diameter reduction), 3 with left PA and 2 with right PA) stenoses had balloon angioplasty. The pulmonary to systemic blood flow ratio between patients requiring pre-stage-2 palliation intervention and patients without intervention was 1. 05 ± 0. 3 versus 1. 13 ± 0. 37 (p = 0. 09). Right PA and left PA growth was balanced (right PA/left PA 0. 99 ± 0. 3; right PA 26. 8 ± 11. 5 mm(2) versus left PA 27. 2 ± 12. 3 mm(2); p = 0. 1). Freedom from significant RV dysfunction for S1P survivors at 3, 6, 12, 36, and 48 months was 94.4% ± 3.1%, 88.7% ± 4.4%, 86.7% ± 4.7%, 83.9% ± 5.3%, and 79.7 ± 6.7%, respectively. CONCLUSIONS: Norwood RV-PA promotes balanced branch PA growth. The RV-to-PA shunt with proximal valvelike hood modification significantly reduces proximal anastomotic stenosis and need for early shunt revision. Limited early shunt diastolic reversal flow into the RV and subsequent early unloading of RV during BDG might preserve ventricular performance.

Hypoplastic left heart syndrome and aortic atresia-mitral stenosis variant: role of myocardial protection strategy and impact of ventriculo-coronary connections after stage I palliation.

Aortic atresia-mitral stenosis (AA-MS) has been implicated as a determinant of outcome after Stage-1 palliation (S1P) in hypoplastic left heart syndrome (HLHS).Studies evaluating the association of AA-MS with ventriculo-coronary connections (VCC) and mortality report conflicting results. The significance of VCC, myocardial protection, and shunt strategy after S1P has yet to be determined. Between January 2005 and July 2009, 100 neonates with HLHS underwent S1P. Mitral and aortic valves and presence of VCC were assessed. Antegrade continuous cold blood cardioplegia was administered throughout the vast extent of the neo-aortic reconstruction. A right ventricle-to-pulmonary shunt was used for an ascending aortic diameter of 0.6 mm/kg or less. Survival analysis was performed to determine predictors and assess impact of AA-MS and VCC on hospital and interstage mortality. Twenty-seven (of 100) patients had AA-MS. The mean age and weight at S1P were 6.5 ± 2.8 days and 3.09 ± 0.47 kg, respectively. VCC were found in 56% of AA-MS. Twenty-two had Norwood-Sano, 3 had classic Norwood, and 2 had hybrid S1P. VCC were associated with AA-MS, endocardial fibroelastosis, and ascending aortic size <2 mm (P < 0.05) but not higher mortality (P = ns). Operative and interstage survival for AA-MS after S1P was 85.2 and 71%, respectively (not statistically different compared to all other subtypes; P = ns). Actuarial survival after S1P at 1, 3, 6, 12, and 36 months was 92.9 ± 4.9, 78.6 ± 7.8, 75 ± 8.2, 71.3 ± 8.3, and 71.3 ± 8.3%, respectively. Intact atrial septum and post-S1P renal dysfunction (P < 0.05) were independent predictors of hospital and interstage mortality. In patients with HLHS, AA-MS carries no survival disadvantage after S1P during the hospital and interstage period regardless of VCC. Intact atrial septum and post-S1P renal dysfunction predict early and interstage mortality. Myocardial protection and shunt strategy might influence the outcome in this HLHS variant.

Mitral stenosis and aortic atresia in hypoplastic left heart syndrome: survival analysis after stage I palliation.

BACKGROUND: Mitral stenosis with aortic atresia (MS-AA) has been implicated as a risk factor for decreased survival after stage 1 palliation for hypoplastic left heart syndrome. Conflicting results were reported in the literature evaluating the association of anatomic subtypes and mortality. Our objective was to determine whether MS-AA is associated with increased mortality after stage 1 palliation. METHODS: Between January 2005 and May 2009 100 consecutive neonates with hypoplastic left heart syndrome underwent stage 1 palliation. Echocardiograms were reviewed for patency of the mitral and aortic valves as well as presence of ventriculocoronary connections (VCC). Patients were divided into (1) mitral and aortic atresia (MA-AA), (2) MS-AA, and (3) mitral and aortic stenosis groups. Survival analysis was performed, and impact of MS-AA and VCC on early and midterm survival was assessed. RESULTS: Of the 100 patients, 31 had MA-AA, 42 had mitral stenosis and aortic stenosis, and 27 had MS-AA (15 with VCC and 12 without). Stage 1 palliation 30-day survival was 90% for the entire cohort and 88.9% for the MS-AA subtype (not significantly different). Six-month survival was 70% overall and 70.4% for MS-AA (not significantly different). When VCC was taken into account, MS-AA with VCC reached 93% survival (versus 50% for MS-AA without VCC; p < 0.01). CONCLUSIONS: Stage 1 palliation for hypoplastic left heart syndrome is associated with satisfactory hospital and midterm survival regardless of anatomic subtype. The variants MS-AA and MA-AA are associated with smaller ascending aorta. Mitral stenosis with aortic atresia or VCC did not adversely influence survival.

Ventriculocoronary artery connections with the hypoplastic left heart: a 4-year prospective study: incidence, echocardiographic and clinical features.

Ventriculocoronary connections (VCCs), also called sinusoids, occur with hypoplastic left heart (HLH). Previous reports are limited to case reports, pathologic series, and surgical series with limited detail, which may underestimate the incidence and overestimate the severity of VCCs in HLH. A study was conducted to determine the incidence VCCs in HLH, their effect on survival, and their echocardiographic and clinical features. The echocardiograms and medical records of 100 consecutive neonatal HLH cases were analyzed. All had an aortic and a mitral valve diameter and a left ventricular (LV) volume less than Z-3. For palliation, Norwood, Sano, or hybrid procedures were used, and if the patient was alive, subsequent bidirectional Glenn and extracardiac Fontan procedures were applied. Cases were classified as manifesting mitral and aortic atresia (MAAA), mitral and aortic stenosis (MSAS), or mitral stenosis and aortic atresia (MSAA). All other diagnoses or any case with additional cardiac anomalies were excluded from the study. Overall, VCCs were found in 15% of the cases. They occurred in 56% of the MSAA subtype cases and were not statistically associated with a high mortality rate. However, in one case, large and multiple VCCs definitely caused or contributed to early death. All VCCs had a transmyocardial course, a turbulent color-Doppler flow, and a dominant usually retrograde systolic coronary artery flow pattern. The VCCs were associated (p < 0.05) with MSAA, endocardial fibroelastosis, and ascending aortic size less than 2 mm. As shown by the findings, 15% of the HLH patients had MSAA with VCCs. Unless the VCCs were large or extensive, they did not contribute to mortality. Detailed echocardiographic analysis of VCCs in HLH was feasible. Recent reports emphasize more severe cases.

Double aortic arch and d-transposition of the great arteries.

We present a rare case of D-transposition of the great arteries (D-TGA) and double aortic arch (DAA). The anatomy was prospectively and preoperatively diagnosed by echocardiography and confirmed by ultra-fast computed tomography. The patient underwent successful arterial switch operation and division of the vascular ring at a single procedure.

Inadvertent stenting of patent ductus arteriosus with Amplatzer Vascular Plug.

We report a 12-month old patient who presented for murmur evaluation after percutaneous closure of type C patent ductus arteriosus (PDA) using a 10 mm Amplatzer Vascular Plug (AGA Medical Corporation, Golden Valley, MN) at an outside institution. Echocardiography revealed a large left-to-right shunt through the implanted device, inadvertently stenting the PDA instead of closing it. The patient underwent repeat catheterization with successful coil implantation within the Amplatzer Vascular Plug, completely eliminating the large residual ductal shunt. Although challenging, this case illustrates the technique of implanting coils within this occlusion device. This case also illustrates that occlusion of type C PDA utilizing the Amplatzer Vascular Plug may not only result in incomplete occlusion but also create a potentially worse clinical situation in which the PDA is stretched larger and stented open. Without consideration of simultaneous coil implantation within this device, use of the Amplatzer Vascular Plug might be contraindicated in type C PDA, because there may be no way to ensure successful closure by the Vascular Plug alone.

Technical considerations for closing secundum atrial septal defect in the small child with the HELEX Septal Occluder via transhepatic access.

We describe closure of an atrial septal defect in a symptomatic 4.6 kg child with the HELEX Septal Occluder (W.L. Gore and Associates, Flagstaff, AZ) via transhepatic approach. Technical considerations are discussed.

Novel approach to the newborn with hypoplastic left heart syndrome and intact atrial septum.

A prenatally diagnosed fetus with hypoplastic left heart syndrome and intact atrial septum was delivered in the cardiac catheterization suite. Using radio frequency energy, a transseptal perforation of the thickened and intact atrial septum was immediately performed following transcatheter cannulation of the right atrium via the umbilical vein. Serial cutting balloon septostomies followed by static balloon septostomies resulted in effective left atrial decompression, atrial mixing, and optimal pulmonary and systemic perfusion. The child is now thriving after both stage I Norwood and bidirectional Glenn procedures.