Accelerated degeneration of a bovine pericardial bioprosthetic aortic valve in children and young adults.

BACKGROUND: Experience with aortic valve replacement (AVR) with current-generation pericardial bioprostheses in young patients is limited. The death of a child with accelerated bioprosthetic aortic stenosis prompted enhanced surveillance of all such patients at our institution. METHODS AND RESULTS: We reviewed records of 27 patients who had undergone AVR (median follow-up, 13.7 months) with a bovine pericardial bioprosthesis at ≤30 years of age. In the Mitroflow LXA valve group (n=15), freedom from valve failure was 100% at 1 year, 53% (95% confidence interval, 12-82) at 2 years, and 18% (95% confidence interval, 1-53) at 3 years. No Magna/Magna Ease valves (n=12) failed by 3 years. Among valve failure patients, median age at AVR was 12 years (range, 10-21 years). Life-threatening prosthetic aortic stenosis was detected at a median of 6 months after prior echocardiograms showing mild or less gradients. Patients with Mitroflow LXA compared with Magna/Magna Ease valves were smaller (median body surface area, 1.42 versus 1.93 m(2); P=0.002) and younger (median age, 13.0 versus 20.9 years; P=0.02) at AVR. Pathology demonstrated diffuse intrinsic leaflet calcification, not associated with inflammation or infection, and virtually immobile leaflets in closed position. CONCLUSIONS: Young patients undergoing AVR with Mitroflow LXA pericardial valves are at high risk for rapid progression from mild or less to severe aortic stenosis over months, highlighting their need for heightened echocardiographic surveillance and suggesting that this aortic bioprosthesis should not be implanted in the young. Current data are insufficient to assess the safety of AVR with other pericardial bioprostheses in children and the youngest adults.

Mortality and Reoperation Risk After Bioprosthetic Aortic Valve Replacement in Young Adults With Congenital Heart Disease.

Bioprosthetic aortic valve replacement (bAVR) in patients with congenital heart disease is challenging due to age, size and complexity. Our objective was to assess survival and identify predictors of re-operation. Data were retrospectively collected for 314 patients undergoing bAVR at 8 centers from 2000-2014. Kaplan-Meier estimation of time to re-operation and Cox regression were utilized. Average age was 45.2 years (IQR 17.8-71.1) and 30% were <21. Indications were stenosis (48%), regurgitation (28%) and mixed (18%). Twenty-eight (9%) underwent prior AVR. Median valve size was 23mm (IQR 21, 25). Implanted valves included CE (Carpentier-Edwards) Perimount (47%), CE Magna/Magna Ease (29%), Sorin Mitroflow (9%), St Jude (2%) and other (13%). Median follow-up was 2.9 (IQR 1.2, 5.7) years. Overall, 11% required re-operation, 35% of whom had a Mitroflow and 65% were <21 years old. Time to re-operation varied among valve type (p=0.020). Crude 3-year rate was 20% in patients ≤21. Smaller valve size indexed to BSA was associated with re-operation (21.7 vs. 23.5 mm/m2). Predictors of reintervention by multivariable analysis were younger age (29% increase in hazard per 5-year decrease, p<0.001), Mitroflow (HR=4 to 8 versus other valves), and smaller valve size (20% increase in hazard per 1 mm decrease, p=0.002). The overall 1, 3 and 5-year survival rates were 94%, 90% and 85% without differences by valve (p=0.19). A concerning reduction in 5-year survival after bAVR is shown. Re-operation is common and varies by age and valve type. Further research is needed to guide valve choice and improve survival.

Reintervention rates after bioprosthetic pulmonary valve replacement in patients younger than 30 years of age: A multicenter analysis.

OBJECTIVES: To assess the difference in time to and predictors of reintervention according to valve type in surgical bioprosthetic pulmonary valve replacement (PVR) in patients younger than 30 years of age from multiple centers. METHODS: Data were retrospectively collected for 1278 patients <30 years of age undergoing PVR at 8 centers between 1996 and 2015. RESULTS: Mean age at PVR was 19.3 ± 12.8 years, with 719 (56.3%) patients ≤18 years of age. Diagnosis was tetralogy of Fallot in 626 patients (50.5%) and 165 (12.9%) had previous PVR. Median follow-up was 3.9 years (interquartile range, 1.2, 6.4). Multiple valve types were used, most commonly CE PERIMOUNT, 488 (38.2%), CE Magna/Magna Ease, 361 (28.2%), and Sorin Mitroflow 322 (25.2). Reintervention occurred in 12.7% and was most commonly due to pulmonary stenosis (68.8%), with most reinterventions occurring in children (85.2%) and with smaller valve sizes (P < .001) Among adults aged 18 to 30 years, younger age was not a significant risk factor for reintervention. Surgical indication of isolated pulmonary regurgitation was associated with a lower risk of reintervention (P < .001). Overall, 1-, 3-, 5-, and 10-year freedom from reintervention rates were 99%, 97%, 92%, and 65%. The only independent risk factors for reintervention after controlling for age and valve size were lack of a concomitant tricuspid valve procedure (P = .02) and valve type (P < .001); Sorin and St Jude valves were associated with similar time to reintervention, and deteriorated more rapidly than other valve types. CONCLUSIONS: In this large multicenter study, 8% of patients have undergone reintervention by 5 years. Importantly, independent of age and valve size, reintervention rates vary by valve type.

Three-Patch Aortic Root Reconstruction With Extended Left Main Coronary Artery Patch Augmentation in Neonates and Infants.

Left main coronary artery (LMCA) stenosis is present in approximately 5% of patients with congenital supravalvular aortic stenosis (SVAS) (Fig. 1)1 and is associated with an increased risk of sudden cardiac death.2 However, patients undergoing coronary artery intervention at the time of SVAS repair are at the highest risk of experiencing major adverse cardiac events.3 Literature reports of surgical techniques and outcomes of concomitant coronary artery repair in these high-risk patients are diverse and inconsistently described. We have recently adopted a standardized surgical technique for management of this complex pathology by combining extended LMCA patch augmentation with a 3-patch aortic root reconstruction (Brom's technique). In this report, we describe our contemporary surgical technique of 3-patch aortic root reconstruction with extended LMCA patch augmentation for patients with congenital SVAS with ostial LMCA stenosis and bilateral outflow tract obstruction. Institutional review board approval was obtained for retrospective review of patient charts.

Augmentation of Bridging Leaflets in Repair of Atrioventricular Canal Defects.

Left atrioventricular (AV) valve regurgitation is the most common complication after a atrioventricular canal defect (AVCD) repair. Despite what appears to be a less complex repair, patients with partial and transitional AV canal have higher reoperation rates for left AV valve regurgitation and left ventricular outflow tract (LVOT) obstruction. Retraction of bridging leaflets with secondary attachments to the septal crest commonly produces increased tension and flattening of the medial left AV valve leaflet and LVOT obstruction after cleft closure. We describe a novel technique of detachment and patch augmentation of bridging leaflets to avoid these complications.

Histology of Pericardial Tissue Substitutes Used in Congenital Heart Surgery.

Pericardium is used as a tissue substitute during pediatric heart surgery. However, little is known about the histological characteristics of pericardial tissue substitutes. We searched our clinical and Pathology databases to identify cases in which glutaraldehyde-preserved autologous pericardium, PhotoFix bovine pericardium, or Peri-Guard Repair Patch glutaraldehyde-preserved bovine pericardium was used as patch material during cardiac surgery and in which explanted tissue substitute was available for histologic examination. Tissue sections were stained with hematoxylin and eosin, Masson trichrome, and Movat pentachrome, and were graded for inflammation, tissue substitute degeneration, neointima formation, and calcification. Nonparametric statistical methods were used to test differences between groups because of small sample size. The eight patients who received PhotoFix pericardium were older (median 10 months vs 10 days, P < 0.05) and the material was in situ longer (median 14 vs 2.5 months, P < 0.05) compared to the eight who received autologous pericardium. Only three patients received glutaraldehyde-preserved bovine pericardium precluding statistical comparison. Inflammation and tissue degeneration were greater in PhotoFix pericardium compared to autologous pericardium but were no more than moderate. Neointima formation and calcification did not differ significantly between the two groups. PhotoFix bovine pericardium is associated with more inflammation and material degeneration but calcification, and neointima formation are similar to autologous pericardium. Although the short-term outcomes are acceptable, calcification and degeneration seen in some cases suggest that long-term outcomes and performance at certain anatomic locations need further study.

Outcomes and Short-Term Follow-Up in Complex Ross Operations in Pediatric Patients Undergoing Damus-Kaye-Stansel Takedown.

Review echocardiography and outcomes before and after Ross procedures, including patients undergoing biventricular conversion with Damus-Kaye-Stansel (DKS) takedown. A retrospective review was performed on 62 patients undergoing simple (control group) and complex Ross procedures, including 12 patients who underwent biventricular conversion with Ross operation and DKS takedown (complex). Echocardiography was reviewed preoperatively and at discharge and late follow-up. Kaplan-Meier estimates of patient survival and freedom from reintervention were obtained. In all, 62 patients had a median age of 4.5 years (interquartile range [IQR]: 1-12.5), weight of 16.4kg (IQR: 8-41), and follow-up of 3.8 years (IQR: 1.3-6). The complex DKS takedown group had 2 deaths, no neoaortic valve or root reinterventions, and 3 right ventricular outflow tract (VOT) reinterventions. There were no differences from the control group in left VOT or right VOT reinterventions. Neither group showed differences between pre- and late follow-up aortic root and ascending aorta dimensions, and no correlations were found among preoperative pulmonary valve (PV) size, late aortic regurgitation (AR), aortic root, or ascending aortic Z-scores. Aortic valve size increased from discharge to late follow-up for both groups (P ≤ .05); 90% of patients at late follow-up had mild or less AR with similar distributions in severity between complex and control groups. Severity of late AR showed no correlation with preoperative PV size and is independent of it. The Ross procedure has good short-term results in simple and complex patients and should be considered in those undergoing Ross operation with biventricular conversion and DKS takedown. Moreover, native PV size should not be a contraindication for Ross procedure.

Outcome and performance of bioprosthetic pulmonary valve replacement in patients with congenital heart disease.

OBJECTIVES: The goal of this single-center series was to assess differences in reintervention by the type of valve used for surgical bioprosthetic pulmonary valve replacement and to identify independent predictors of reintervention. METHODS: Data were retrospectively collected for 611 patients undergoing pulmonary valve replacement from 1996 to 2014. Kaplan-Meier estimation and Cox proportional hazards regression methodologies were used. RESULTS: The median age of patients was 17.8 years (interquartile range, 11.9-27.3). The diagnosis was tetralogy of Fallot in 69% of patients. The median follow-up was 3.0 years (interquartile range, 1.1-5.3). Valve types included Sorin Mitroflow (Milan, Italy), 316 (50%; median age 16.5 years); Carpentier-Edwards (Irvine, Calif) Magna/MagnaEase, 223 (35%; median age, 19.3 years); and Carpentier-Edwards Perimount, 72 (11%; median age, 21.9 years). Reintervention occurred in 6.7% of patients (41/633) and was higher in children than adults (hazard ratio, 4.8). Age-adjusted 5-year reintervention rates were Sorin Mitroflow, 13.4%; Carpentier-Edwards Magna/MagnaEase, 2.1%; and Carpentier-Edwards Perimount, 0%. Reintervention was not associated with gender, valve insertion method, or concurrent procedures. The only independent risk factor for reintervention after controlling for age was valve type (P < .001). The Sorin Mitroflow valve had a shorter time to reintervention than the other 2 valve types (hazard ratios both >7, each P < .001). Differences by valve type did not depend on age (interaction P = .61). CONCLUSIONS: Bioprosthetic pulmonary valve replacement in patients with congenital heart disease has excellent short-term outcomes, but children have an approximately 5-fold greater risk of reintervention than adults. Independently of age, reintervention rates vary by valve type. These differences may be important in valve selection and follow-up.

Pediatric thoracic organ transplants: challenges in primary care.

Pediatric nurse practitioners (PNP) confront numerous challenges when delivering care to infants, children, and adolescents who receive thoracic organ transplants. Today, thoracic organ transplantation is an acceptable and viable option for infants, children, and adolescents with end stage cardiac and pulmonary disease. Despite the plateau in the actual numbers of thoracic organ transplants performed annually in the United States, they are still being performed in a significant number. The care of children who receive transplants includes long-term use of immunosuppressants, dealing with infectious diseases, and utilizing principles of well child and family care. PNPs play a vital role in providing holistic care to infants, children, and adolescents who receive a thoracic organ transplant.