Phillip T. Burch

Coarctation repair in neonates and young infants: Is small size or low weight still a risk factor?

OBJECTIVE Previous reports of neonatal coarctation repair demonstrate a high rate of recurrent arch obstruction in small neonates. This study assesses the effect of patient size on reintervention and survival in neonates and infants undergoing repair of simple aortic coarctation. METHODS From 1996 to 2006, 167 neonates and infants younger than 90 days with simple coarctation underwent repair. Median patient age was 16 days (range, 1-85 days). Median patient weight was 3.4 kg (range, 0.8-6.0 kg), with 29 patients weighing less than 2.5 kg. All 167 patients included in the study underwent repair through a left thoracotomy. RESULTS There was 1 early death (1/167, 0.6%). Median follow-up of 4.8 years (range, 0-11.8 years) demonstrated 2 late deaths unrelated to recurrent coarctation. Eighteen patients underwent intervention for recurrent arch obstruction a median of 0.48 years postoperatively (range, 0.14-9.8 years). All were treated with balloon angioplasty and have required no additional intervention. Actuarial freedom from reintervention was 90% at 1 year and 89% at 5 years for infants weighing more than 2.5 kg and 89% at 1 year and 86% at 5 years (P = .31) for infants weighing less than 2.5 kg. There was no difference between survival or reintervention for neonates 30 days of age or younger compared with infants 31 to 90 days of age. Use of polypropylene sutures and female sex did correlate with increased reintervention. CONCLUSIONS Low weight does not affect survival or reintervention rates after coarctation repair in neonates and infants less than 3 months of age. Balloon angioplasty is an effective treatment for recurrent obstruction after coarctation repair in infancy. In the current era, timing of the operation should be based on clinical status.

Clinical performance of decellularized cryopreserved valved allografts compared with standard allografts in the right ventricular outflow tract.

BACKGROUND Although decellularized cryopreserved valved allografts (DCAs) have reduced immunogenicity, proof of clinical superiority over standard cryopreserved allografts (SCAs) is lacking. To assess functional results and durability, we studied a group of patients with DCAs implanted between 2000 and 2005 and compared them with a similar group with SCAs. METHODS From July 2000 until January 2005, 47 patients underwent insertion of a DCA between the right ventricle and pulmonary arteries. The DCA patients were compared with 47 age-matched and diagnosis-matched controls receiving SCAs. All patients received pulmonary allografts and were matched for valve position (orthotopic versus heterotopic). We analyzed each group for survival, reoperation, reintervention (surgical or catheter-based), stenosis, and regurgitation. RESULTS There were no differences between groups with respect to weight, age, valve size, or survival. Actuarial freedom from reintervention at 8 years was 79% for DCAs as compared with 63% for SCAs (p = 0.31, log-rank). Echocardiogram in the DCA group (median 66 months) showed a slightly lower median peak gradient of 16 mm Hg (range, 0 to 82 mm Hg) as compared with 22 mm Hg (range, 0 to 63) in the SCA group (median 61 months, p = 0.051, Wilcoxon). However, when conduits 18 mm or less in diameter were compared, DCA patients had a median peak gradient of 10 mm Hg (range, 0 to 43) compared with 25 mm Hg in SCAs (range, 0 to 55 mm Hg, p = 0.03). There were no differences in the degree of allograft insufficiency in either group. CONCLUSIONS Decellularized cryopreserved valved allografts have a nonsignificant trend toward lower peak valve gradient and reintervention in comparison with SCAs. Small valve sizes (18 mm or less) show a slight but significant improvement in peak gradient, but no advantage in valve insufficiency. These findings and a significantly higher cost (>

Stentless porcine valves in the right ventricular outflow tract: improved durability?

3,000) make further direct comparisons necessary before widespread use of DCAs can be justified.

Experience With the Levitronix CentriMag in the Pediatric Population as a Bridge to Decision and Recovery

OBJECTIVE Stentless porcine valves are commonly used for aortic valve replacement in adults, yet their long-term performance in the right ventricular (RV) outflow tract is unknown. We evaluated intermediate-term performance of stentless porcine valves in the RV outflow tract in 150 children and adults over a 10-year period. METHODS We retrospectively reviewed data on all patients undergoing placement of a pulmonary valve or RV-PA conduit with a stentless porcine prosthesis (>/=19 mm) from 1998 to 2008. Valvar function was assessed with echocardiography. Freedom from reintervention (explantation or catheter-based intervention) was determined by actuarial methods. RESULTS A stentless porcine prosthesis was placed in the pulmonary position in 150 patients with a median weight and age of 50.1 kg (range 9.8-127) and 15.8 years (range 1.4-55), respectively. There were three early deaths (2%) and no late deaths. Actuarial freedom from reintervention was 100% at 1 year and 95.5% at 5 years. Peak transvalvar gradient at 1 and 5 years was 13+/-12 mmHg and 25+/-11 mmHg, respectively. At last follow-up no patient had severe insufficiency (PI), five patients had moderate PI and the remainder mild or no PI. CONCLUSIONS Stentless porcine valves function well in the pulmonary position over the intermediate-term and are associated with low rates of reintervention in patients requiring a >19 mm valve or valved conduit. Longer-term follow-up and comparison with other alternatives will be necessary to determine if these valves are superior to commonly used allograft or bovine jugular venous valved conduits.

Longitudinal Assessment of Growth in Hypoplastic Left Heart Syndrome: Results From the Single Ventricle Reconstruction Trial

Short-term mechanical circulatory support in the pediatric population with acute cardiac failure has traditionally been limited to extracorporeal membrane oxygenation given the limited availability of pediatric-sized pumps. The Levitronix CentriMag system (Thoratec Corporation, Pleasanton, CA, USA) offers expanded options for short-term support for this population. We report our experience with the successful use of the CentriMag in the pediatric population as a bridge to decision after postcardiotomy ventricular failure and as a bridge to recovery after heart transplantation. The first patient was bridged to a long-term HeartMate II (Thoratec Corporation) as a bridge to potential recovery. The second patient was supported after severe graft failure post heart transplantation, with a full recovery. The Levitronix CentriMag has proven to be a versatile, safe, and effective short-term circulatory support system for our pediatric patients.

Durability of Truncal Valve Repair

Background We sought to characterize growth between birth and age 3 years in infants with hypoplastic left heart syndrome who underwent the Norwood procedure. Methods and Results We performed a secondary analysis using the Single Ventricle Reconstruction Trial database after excluding patients <37 weeks gestation (N=498). We determined length‐for‐age z score (LAZ) and weight‐for‐age z score (WAZ) at birth and age 3 years and change in WAZ over 4 clinically relevant time periods. We identified correlates of change in WAZ and LAZ using multivariable linear regression with bootstrapping. Mean WAZ and LAZ were below average relative to the general population at birth (P<0.001, P=0.05, respectively) and age 3 years (P<0.001 each). The largest decrease in WAZ occurred between birth and Norwood discharge; the greatest gain occurred between stage II and 14 months. At age 3 years, WAZ and LAZ were <−2 in 6% and 18%, respectively. Factors associated with change in WAZ differed among time periods. Shunt type was associated with change in WAZ only in the Norwood discharge to stage II period; subjects with a Blalock‐Taussig shunt had a greater decline in WAZ than those with a right ventricle‐pulmonary artery shunt (P=0.002). Conclusions WAZ changed over time and the predictors of change in WAZ varied among time periods. By age 3 years, subjects remained small and three times as many children were short as were underweight (>2 SD below normal). Failure to find consistent risk factors supports the strategy of tailoring nutritional therapies to patient‐ and stage‐specific targets. Clinical Trial Registration URL: http://clinicaltrials.gov/. Unique identifier: NCT00115934.

Management of Deep Wound Complications With Vacuum-Assisted Therapy After Berlin Heart EXCOR Ventricular Assist Device Placement in the Pediatric Population

BACKGROUND Truncus arteriosus associated with truncal valve dysfunction has been shown to increase the mortality and morbidity associated with repair and the various techniques employed for truncal valve repair continue to evolve. We sought to examine the durability of truncal valve repair in truncus arteriosus. METHODS We reviewed all patients who underwent truncal valve repair at our institution from 1995 to 2008. Repair techniques included leaflet delamination, bicuspidization, commissuroplasty, annuloplasty, and leaflet augmentation. We examined long-term valve durability, function and need for valve replacement. RESULTS A total of 17 patients underwent truncal valve repair, including 3 for predominant stenosis (>70 mm Hg gradient), 2 for mixed moderate stenosis (40 mm Hg gradient) and moderate regurgitation, and 12 for moderate or greater regurgitation. Of these, 14 patients (14 of 17, 82%) underwent valvuloplasty at the time of the initial truncus arteriosus repair. The median age at truncal valve repair was 24 days (range, 4 days to 42 years). Thirteen patients had 1 valvuloplasty, 3 patients had 2 valvuloplasties, and 1 patient had 3 valvuloplasties before undergoing a prosthetic valve replacement at age 13 years. Actuarial freedom from repeat truncal valve operation was 70% at 5 years and 50% at 7 years. Freedom from truncal valve replacement was 100% at 10 years. To date, only 1 patient (6%) has required a prosthetic valve. Echocardiography at 48 ± 33 (mean ± SD) months postoperatively showed a peak gradient of 11 ± 13 mm Hg; 6 patients have moderate regurgitation, and the rest have mild or less regurgitation. CONCLUSIONS Truncal valve repair is a durable option with an acceptable reoperation rate, good function, and a low likelihood of needing truncal valve replacement. This is one of the largest series of truncal valve repairs and emphasizes that valve repair should remain the primary option.

Simple versus complex truncus arteriosus: neutralization of risk but with increased resource utilization.

Wound complications after ventricular assist device (VAD) placement remain a formidable challenge to surgeons. The Berlin Heart EXCOR VAD is a versatile pulsatile system that has been successful in pediatric patients of all ages and sizes. Prevention of device-related complications such as infection, particularly in pediatric patients, remains an essential issue in minimizing patient morbidity and mortality. The introduction of vacuum-assisted wound closure (VAC) therapy and its application in VAD-related wound complications provide an efficient and effective method for wound healing. We report our experience in the management of deep wound complications in two pediatric patients after placement of the Berlin Heart EXCOR VAD. The wound VAC system proved to achieve complete wound healing without any infectious complications.

Effect of Endovascular Stenting of Right Ventricle to Pulmonary Artery Conduit Stenosis in Infants With Hypoplastic Left Heart Syndrome on Stage II Outcomes

This study examined simple versus complex forms of truncus arteriosus (TA) results in the current era with regard to mortality, reintervention, and resource utilization. From 1999 to 2008, 42 infants underwent primary repair of TA, including 22 simple forms of TA without associated anomalies and 20 complex forms with risk factors such as interrupted aortic arch (n = 8), coarctation (n = 1), significant truncal valve regurgitation (n = 6), discontinuous pulmonary arteries (n = 3), and truncal valve stenosis (n = 2). There were 4 early deaths (4/42, 9.5%), with no difference between simple TA (2/22, 9.1%) and complex TA (2/20, 10%). Early mortality decreased to 1 patient (1/23, 4%) in the most recent era: 2003-2008. Late mortality occurred in 4 (4/38, 10.5%). Reintervention was required in 12 patients, a median of 2 years postoperatively: for conduit reasons in 8 and combined conduit and truncal valve insufficiency in 4. Actuarial survival was 82% ± 7% at 5 years and freedom from reintervention was 52% ± 17% at 5 years, which are not different between complex and simple forms. Complex TA, age, and weight were not predictors on multivariable analysis for early or late death or reintervention. Complex TA had significantly longer (P < .05) median length of stay (17 vs 13 days) and intensive care unit intubation times (8 vs 5 days) versus simple TA. Complex TA does not have a higher operative or late mortality risk or increased risk of reintervention compared with simple TA. However, complex patients can be expected to have increased resource utilization as compared with simple forms of TA.

Assessment of Growth 6 Years after the Norwood Procedure.

There is growing awareness that the Norwood procedure with the Sano modification is prone to early right ventricular to pulmonary artery (RV-PA) conduit stenosis resulting in systemic oxygen desaturation, increased interstage morbidity, and death. We report our experience with endovascular stent placement for conduit stenosis and compare the outcomes at stage II surgery between stented and nonstented infants. The medical records of all patients with hypoplastic left heart syndrome who received an RV-PA conduit at Norwood palliation from May 2005 to January 2010 were reviewed. The preoperative anatomy, demographics, operative variables, and outcomes pertaining to the Norwood and subsequent stage II surgeries were obtained and compared between stented and nonstented infants. The pre- and post-stent oxygen saturation, stenosis location, type and number of stents implanted, concomitant interventions, procedure-related complications, and reinterventions were collected. Of the 66 infants who underwent the Norwood procedure with RV-PA conduit modification, 16 (24%) received stents. The anatomy, demographics, and outcome variables after the Norwood procedure were similar between the stented and nonstented infants. The age at catheterization was 93 ± 48 days, and the weight was 4.9 ± 1.2 kg. The oxygen saturation increased from 66 ± 9% before intervention to 82 ± 6% immediately after stenting (p <0.0001). No interstage surgical shunt revisions were performed in either group. Age, weight, pre-stage II echocardiographic variables, oxygen saturation, and operative and outcome variables, including mortality, were similar between the 2 groups. In conclusion, endovascular stent placement for RV-PA conduit stenosis after the Norwood procedure leads to improved systemic oxygen levels and prevents early performance of stage II surgery without compromising stage II outcomes.