Mid-term performance of decellularized equine pericardium in congenital heart surgery.

OBJECTIVE: The aim was to report mid-term performance of decellularized equine pericardium used for repair of various congenital heart defects in the pediatric population. METHODS: A retrospective review of all patients undergoing patch implantation between 2016 - 2020 was performed. Patch quality, surgical handling, hemostasis and early patch-related complications were studied on all patients. Mid-term performance was observed in patients with ≥12 months follow-up and intact patch at discharge (without reoperation/stent implantation). RESULTS: A total of 201 patients with median age of 2.5 years [interquartile range (IQR): 0.6-6.5] underwent 207 procedures at 314 implant locations. The patch was used in following numbers/locations: 171 for pulmonary artery (PA) augmentation, 36 for aortic repair, 35 for septal defect closure, 22 for valvular repair and 50 at other locations. Early/30-day mortality was 6.5%. Early patch-related reoperations/stent implantations occurred in 28 locations (8.9%). No patch-related complications were noted except for bleeding from implant site in three locations (1%). Follow-up ≥ 12 months was available for 132 patients/200 locations. During a median follow-up of 29.7 months [IQR: 20.7-38.3], 53 patch-related reoperations/catheter reinterventions occurred (26.5%) with the majority in PA position (88.7%, 47/53). Overall 12- and 24-months freedom from patch-related reoperation/catheter reintervention per location was 91.5% (95% CI: 86.7%-94.6%) and 85.2% (95% CI: 78.9%-89.6%) respectively. CONCLUSION: Decellularized equine pericardium used for repair of various congenital heart defects showed acceptable mid-term performance. Reoperation/reintervention rates were in a range as observed with other xenogeneic materials previously reported articles, occurring most frequently after PA augmentation.

Anatomic Repair of Congenitally Corrected Transposition: Reappraisal of Eligibility Criteria.

Several criteria to identify suitable candidates for anatomic repair in congenitally corrected transposition (cc-TGA) have been proposed. The purpose of this study was to critically re-evaluate adequacy of these recommendations in our patient cohort. All cc-TGA patients undergoing anatomic repair between 2010 and 2019 were reviewed. Evaluated eligibility criteria for repair included age ≤ 15 years, LV mass index ≥ 45-50 g/m2, LV mass/volume ratio > 0.9-1.5 and systolic LV to right ventricle pressure ratio > 70-90% among others. Repair failure was defined as postoperative early mortality or LV dysfunction requiring mechanical circulatory support. Twenty-five patients were included (median [interquartile range] age at surgery 1.8 years [0.7;6.6]; median postoperative follow-up 3.2 years [0.7;6.3]). Median preoperative LV ejection fraction was 60% [56;64], indexed LV mass 48.5 g/m2 [43.7;58.1] and LV mass/volume ratio 1.5 [1.1;1.6], respectively. A total of 12 patients (48%) did not meet at least one of the previously recommended criteria, however, all but two patients (92%) experienced favorable early outcome. Of 7 patients (28%) with indexed LV mass < 45 g/m2, 6 were successfully operated. There were two early repair failures (8%) with LV dysfunction: one patient died and one required mechanical circulatory support but recovered well. Surgery was performed successfully in patients with LV mass and volume Z-scores as low as - 2 and - 2.5, respectively. Anatomic correction for cc-TGA can be performed with excellent early outcome and is feasible even in patients with LV mass below previously recommended cut-offs. The use of LV mass and volume Z-scores might help to refine eligibility criteria.

Pulmonary artery augmentation using decellularized equine pericardium (Matrix Patch™): initial single-centre experience.

OBJECTIVES: The aim of this study was to report our initial experience when using Matrix Patch™ a cell-free equine-derived pericardium for the augmentation of branch pulmonary arteries (PAs) in children. METHODS: Between September 2016 and September 2019, Matrix Patch was used for the augmentation of branch PAs in 96 patients and implanted in 147 separate locations. The median age at implantation was 3.2 years (interquartile range: 0.9-8.4), and 33% of patients were infants. The patch was used mainly in redo surgeries (89.6%). Intra-procedural feasibility and reinterventions were analysed. Primary end points were death or patch-related reoperation/stent implantation. Explanted patches were stained for recellularization/calcification, or to reveal proliferation/inflammation. RESULTS: A total of 81 patients, who received patches in 119 separate locations, were followed within a median of 20 months (interquartile range: 10.2-30.2). Patients with early reoperation/stent implantation were excluded from follow-up. No patch-related death was noted. Survival at last follow-up was 88% (95% CI: 78.8-93.7%). Overall probability of freedom from reoperation/stent implantation per location, 12 and 24 months after initial surgery was 85.8% (95% CI: 76.2-91.7%) and 78.7 (95% CI: 65.9-87.2%), respectively. At 20 months, superficial proliferation with discrete macrophage activity was seen in explants; however, no signs of calcification are observed. CONCLUSIONS: The initial experience with the Matrix Patch in PAs showed comparable results to other xenogeneic patch materials. Long-term follow-up data are needed to prove the desired durability of the patch in different locations.

Subcoronary Ross/Ross-Konno operation in children and young adults: initial single-centre experience.

OBJECTIVES: We sought to evaluate the outcome after modified subcoronary Ross/Ross-Konno operation in children and young adults. METHODS: Between January 2013 and January 2019, a total of 50 patients with median age of 6.3 years (range 0.02-36.5 years, 58% males), including 10 infants (20%), received modified subcoronary Ross/Ross-Konno operation at our institution. Survival, morbidity, reinterventions, aortic valve function and aortic root dimensions were analysed. RESULTS: At a median follow-up of 31.2 months (range 14.4-51 months), there were 1 early death and 1 late death, both in the infant group. The overall survival at 5 years after the operation was 95%. Two patients needed aortic valve replacement, 11 and 15 months after their Ross operation. At 5 years, freedoms from reoperation on the autograft and on the right ventricle to pulmonary artery conduit were 94% and 97%, respectively. Freedom from aortic valve regurgitation greater than mild was 97% at 5 years. Median dimensions of the aortic root at all levels remained in normal range at last visit. Forty-four patients (95%) were in New York Heart Association class I with normal left ventricular function. CONCLUSIONS: The initial experience with the subcoronary Ross/Ross-Konno operation in children and young adults showed excellent outcome. The mortality and morbidity among infants remain significant. The described technique is reproducible and might be advantageous in situations when prosthetic supporting techniques interfere with somatic growth.

Fast-track extubation after cardiac surgery in infants: Tug-of-war between performance and reimbursement?

OBJECTIVES: To compare the safety and resource-efficacy of the fast-track (FT) concept (extubation ≤8 hours after surgery) versus the conventional approach (non-FT, >8 hours postoperatively) in infants undergoing open-heart surgery. METHODS: Infants <7 kg operated on cardiopulmonary bypass between 2014 and 2018 were analyzed. Propensity score matching (1:1) was performed for group comparison (FT vs non-FT). Intensive care unit (ICU) personnel use and unit performance were evaluated. Postoperative outcome and reimbursement based on German diagnosis-related groups were compared. RESULTS: Of 717 infants (median age: 4 months, Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery mortality score: 0.1-4), FT extubation was achieved in 182 infants (25%). After matching, 123 pairs (FT vs non-FT) were formed without significant differences in baseline characteristics. FT versus non-FT showed a significantly shorter ICU stay (in days): 1.8 (0.9-2.8) versus 4.2 (1.9-6.4), P < .01, and postoperative length of stay (in days): 7 (6-10) versus 10 (7-15.5), P < .01; significantly lower postoperative transfusion rates: 61.3% versus 77%, P < .01; and tendency toward lower early mortality: 0% versus 2.8%, P = .08. Reintubation rate did not differ between the groups (P = .7). Despite a decrease in personnel capacity (2014 vs 2018), the unit performance was maintained. The mean case-mix-index of FT versus non-FT was 8.56 ± 6.08 versus 11.77 ± 12.10 (P < .01), resulting in 27% less reimbursement in the FT group. CONCLUSIONS: FT concept can be performed safely and resource-effectively in infants undergoing open-heart surgery. Since German diagnosis-related group systems reimburse costs, not performance, there is little incentive to avoid prolonged mechanical ventilation. Greater ICU turnover rates and excellent postoperative outcomes are not rewarded adequately.

Mitochondrial transplantation by intra-arterial injection for acute kidney injury.

Acute kidney injury is a common clinical disorder and one of the major causes of morbidity and mortality in the postoperative period. In this study, the safety and efficacy of autologous mitochondrial transplantation by intra-arterial injection for renal protection in a swine model of bilateral renal ischemia-reperfusion injury were investigated. Female Yorkshire pigs underwent percutaneous bilateral temporary occlusion of the renal arteries with balloon catheters. Following 60 min of ischemia, the balloon catheters were deflated and animals received either autologous mitochondria suspended in vehicle or vehicle alone, delivered as a single bolus to the renal arteries. The injected mitochondria were rapidly taken up by the kidney and were distributed throughout the tubular epithelium of the cortex and medulla. There were no safety-related issues detected with mitochondrial transplantation. Following 24 h of reperfusion, estimated glomerular filtration rate and urine output were significantly increased while serum creatinine and blood urea nitrogen were significantly decreased in swine that received mitochondria compared with those that received vehicle. Gross anatomy, histopathological analysis, acute tubular necrosis scoring, and transmission electron microscopy showed that the renal cortex of the vehicle-treated group had extensive coagulative necrosis of primarily proximal tubules, while the mitochondrial transplanted kidney showed only patchy mild acute tubular injury. Renal cortex IL-6 expression was significantly increased in vehicle-treated kidneys compared with the kidneys that received mitochondrial transplantation. These results demonstrate that mitochondrial transplantation by intra-arterial injection provides renal protection from ischemia-reperfusion injury, significantly enhancing renal function and reducing renal damage.

Fontan with lateral tunnel is associated with improved survival compared with extracardiac conduit.

OBJECTIVES: The study aim was to compare Fontan patients undergoing lateral tunnel (LT) versus extracardiac conduit (ECC) technique. METHODS: Fontan patients (LT vs ECC) from January 2000 to December 2017 were analyzed retrospectively. Baseline characteristics were analyzed as covariates. Primary outcomes (ie, mortality, Fontan failure, thrombosis, and pacemaker implantation) were compared using time-to-event models. Subgroup analysis including only initially fenestrated cases and propensity score matching were performed. RESULTS: Eight hundred one Fontan patients: LT (n = 638) versus ECC (n = 163) were included. Median follow-up time was 4.8 years (range, 1.1-10.8 years). Baseline characteristics were similar except for age: LT versus ECC: 2.6 years (range, 2.2-3.2 years) versus 3.1 years (range, 2.6-4.7 years) (P < .01) and mean pulmonary artery pressure: LT versus ECC: 12 mm Hg (11-15 mm Hg) versus 11 mm Hg (10-13 mm Hg) (P < .05). Early mortality was significantly higher in ECC versus LT group (3.1%; vs 0.5%; P < .05). Freedom from death, heart transplantation and Fontan failure were significantly longer in LT vs ECC (P < .01). After correcting for age, diagnosis, surgical technique, surgeon, mean pulmonary artery pressure, and fenestration, the ECC group showed worse freedom from death (hazard ratio, 2.8; P < .01) and Fontan failure (hazard ratio, 3.0; P < .01). No difference in pacemaker implantation rate was demonstrated (P = .25). Early fenestration closure was associated with higher risk of early (hazard ratio, 30.5) and late mortality (hazard ratio, 3.5). After matching, log-rank tests showed significant differences between the 2 groups for Fontan failure at 5 and 10 years (P < .01) and mortality at 5 years (P = .02). CONCLUSIONS: When compared with ECC, LT Fontan is associated with better short and midterm outcomes. Spontaneous fenestration closure is an independent risk factor for early/late mortality.

Do patients with anomalous origin of the left coronary artery benefit from an early repair of the mitral valve?

OBJECTIVES: The aim of this study was to determine mid-term outcomes of patients with anomalous origin of the left coronary artery from the pulmonary artery undergoing coronary repair only (group A) or simultaneous mitral valve repair (group B). METHODS: Patients with anomalous origin of the left coronary artery from the pulmonary artery who underwent surgery from 2000 to 2017 were reviewed. Mitral regurgitation (MR) grade (none, mild, moderate, severe), left ventricular (LV) function [ejection fraction (EF): <40%, 40-50%, >50%] and LV Z-scores (long axis) were assessed preoperatively and at last visit. Outcomes were compared within/between the groups using the Wilcoxon signed-rank test. RESULTS: Of 58 patients (67% women; median age 4.4 months), 39 patients were in group A (67%) and 19 patients in group B (33%). The median hospital stay (11 days, interquartile range 5-18) and average follow-up time (2.6 ± 0.5 years) did not differ significantly between the groups (P > 0.05). Four patients in group A (10.3%) underwent mitral valve reintervention. The median MR grade differed significantly between the groups preoperatively (2 vs 3, P < 0.001) but not at the last visit (2 vs 2, P = 0.88); both groups improved significantly (P = 0.021, P < 0.001). EF grade (<40%, 40-50%, >50%) did not differ significantly between the groups at baseline (group A: 38%/23%/38% vs group B: 58%/10%/32%, P = 0.32) or at last visit (group A: 18%/15%/67% vs group B: 26%/16%/58%, P = 0.75); both groups improved significantly (P = 0.004, P = 0.014). The mean LV Z-scores for groups A and B were 3.1 ± 0.5 and 4.5 ± 0.6 before surgery (P < 0.05) and 1.5 ± 0.3 and 2.7 ± 0.6 at last visit (P = 0.77). CONCLUSIONS: The repair of anomalous origin of the left coronary artery from the pulmonary artery is associated with improvement in MR, EF and LV dimensions. However, in cases of ≥moderate MR, the risk of mitral valve reintervention may be higher in patients undergoing coronary transfer only.