Fuxia Yan

Strategy for biventricular outflow tract reconstruction: Rastelli, REV, or Nikaidoh procedure?

OBJECTIVE Three techniques have been developed as the surgical management for patients with anomalies of ventriculoarterial connection, ventricular septal defect, and pulmonary outflow tract obstruction (stenosis): the Rastelli, Lecompte, (REV), and Nikaidoh procedures. This study was designed to compare these procedures in terms of hemodynamics of the reconstructed biventricular outflow tract, early clinical consequences, and follow-up. METHODS Between March 2004 and September 2006, a total of 30 consecutive patients underwent double root translocation procedures (modified Nikaidoh n = 11, REV n = 7, Rastelli n = 12). In the Nikaidoh procedure, both aortic and pulmonary roots were translocated. A single-valved bovine jugular vein patch was used to repair the stenotic pulmonary artery in both Nikaidoh and REV procedures. The Senning procedure was added for those with atrioventricular discordance. RESULTS The Nikaidoh procedure was the most time-consuming in terms of mean cardiopulmonary bypass and aortic crossclamp times. The average mechanical ventilation time was significantly shorter in the Rastelli group (63.3 +/- 89 hours) than that in the Nikaidoh group (188.7 +/- 159 hours, P = .016), but not different from that in the REV group (76.4 +/- 112.5 hours, P = .395). Two patients in the REV group and 1 in the Rastelli group died. There were no in-hospital or late deaths in the Nikaidoh group. Postoperative echocardiography demonstrated physiologic hemodynamics in the left ventricular outflow tract and normal heart function in the Nikaidoh group. Abnormal flow pattern in the left ventricular outflow tract was noted in both REV and Rastelli groups. There were no late deaths or reoperations in any group during follow-up. CONCLUSION The modified Nikaidoh procedure is a better surgical option for transposition of the great arteries, ventricular septal defect, and pulmonary stenosis in terms of physiologic cardiac hemodynamics. Its long-term benefits need to be evaluated with a larger number of patients and longer follow-up.

Alda-1 Attenuates Lung Ischemia-reperfusion Injury by Reducing 4-hydroxy-2-nonenal in Alveolar Epithelial Cells

Objectives: Excessive oxidative stress is a main cause of lung ischemia-reperfusion injury, which often results in respiratory insufficiency after open-heart surgery for a cardiopulmonary bypass. Previous studies demonstrate that the activation of aldehyde dehydrogenase-2 could significantly reduce the oxidative stress mediated by toxic aldehydes and attenuate cardiac and cerebral ischemia-reperfusion injury. However, both the involvement of aldehydes and the protective effect of the aldehyde dehydrogenase-2 agonist, Alda-1, in lung ischemia-reperfusion injury remain unknown. Design: Prospective laboratory and animal investigation were conducted. Setting: State Key Laboratory of Cardiovascular Disease. Subjects: Primary human pulmonary alveolar epithelial cells, human pulmonary microvascular endothelial cells, and Sprague-Dawley rats. Interventions: A hypoxia/reoxygenation cell-culture model of human pulmonary alveolar epithelial cell, human pulmonary microvascular endothelial cell, and an isolated-perfused lung model were applied to mimic lung ischemia-reperfusion injury. We evaluated the effects of Alda-1 on aldehyde dehydrogenase-2 quantity and activity, on aldehyde levels and pulmonary protection. Measurements and Main Results: We have demonstrated that ischemia-reperfusion–induced pulmonary injury concomitantly induced aldehydes accumulation in human pulmonary alveolar epithelial cells and lung tissues, but not in human pulmonary microvascular endothelial cells. Moreover, Alda-1 pretreatment significantly elevated aldehyde dehydrogenase-2 activity, increased surfactant-associated protein C, and attenuated elevation of 4-hydroxy-2-nonenal, apoptosis, intercellular adhesion molecule-1, inflammatory response, and the permeability of pulmonary alveolar capillary barrier, thus alleviated injury. Conclusions: Our study indicates that the accumulation of 4-hydroxy-2-nonenal plays an important role in lung ischemia-reperfusion injury. Alda-1 pretreatment can attenuate lung ischemia-reperfusion injury, possibly through the activation of aldehyde dehydrogenase-2, which in turn removes 4-hydroxy-2-nonenal in human pulmonary alveolar epithelial cells. Alda-1 pretreatment has clinical implications to protect lungs during cardiopulmonary bypass.

Ulinastatin as a neuroprotective and anti-inflammatory agent in infant piglets model undergoing surgery on hypothermic low-flow cardiopulmonary bypass

Infants are potentially more susceptible to brain injury mediated via cell death attributed to cardiopulmonary bypass (CPB) especially with prolonged hypothermic low flow (HLF). We hypothesized that a human urinary protease inhibitor (ulinastatin), by its anti‐inflammatory effect, would reduce central nervous system (CNS) injury during HLF.

Evidence-based use of FFP: the influence of a priming strategy without FFP during CPB on postoperative coagulation and recovery in pediatric patients:

Objective: Although fresh frozen plasma (FFP) is one of the most commonly used hemostatic agents in clinical specialties today, there is little evidence available supporting its administration. Our present study observed the effects of a priming strategy without FFP during cardiopulmonary bypass (CPB) on postoperative coagulation and clinical recovery in pediatric patients, aiming to supply new evidence for evidence-based use of FFP. Method: Eighty pediatric patients with congenital heart disease undergoing cardiac surgery with CPB were randomized to receive either 10-20 ml/kg 4% succinylated gelatin (Gelofusine, GEL group, n = 40) or 1-2 units FFP (FFP group, n = 40) in the pump prime. Rapid-thromboelastography (r-TEG) and functional fibrinogen level were measured before skin incision and 15 minutes after heparin reversal. We recorded the volume of chest tube drainage, transfusion requirements and the dosage of pharmacological agents. The ventilation time, ICU length of stay and hospitalization time after surgery were also collected. Results: After heparin neutralization, there were significantly elevated levels of fibrinogen in the FFP group, which were manifested by r-TEG parameters MAf and FLEV. No significant differences were observed between the two groups in postoperative bleeding, transfusion requirements and the usage of pharmacological agents. Recovery time was also comparable between the two groups. Conclusion: In conclusion, prophylactic use of FFP in the priming solution does not provide clinical benefits as presumed. Artificial colloids, such as Gelofusine, can be used safely and effectively as a substitute for FFP in the pump prime. TEG is an effective assessment tool to evaluate postoperative coagulation function in pediatric patients.

Multistage pulmonary artery rehabilitation in patients with pulmonary atresia, ventricular septal defect and hypoplastic pulmonary artery

OBJECTIVES The aim of this study was to determine the effect of multistage pulmonary artery (PA) rehabilitation consisting of right ventricle to pulmonary artery (RV-PA) connection, major aortopulmonary collateral artery (MAPCA) closure and PA angioplasty in patients with pulmonary atresia, ventricular septal defect (VSD) and hypoplastic pulmonary arteries. In addition, the effects of the PA reintervention were reported and risk factors were analysed. METHODS This study was a retrospective review of 69 consecutive patients with pulmonary atresia, VSD and hypoplastic pulmonary arteries (mean Nakata index 100.9 ± 57.6 mm(2)/m(2)) who underwent multistage rehabilitation of hypoplastic PA from December 2009 to December 2014. RESULTS RV-PA connection was performed at a median age of 1.0 years with 2 hospital deaths in the hybrid operation theatre. Thirty-two patients underwent concomitant pulmonary angioplasty with 28 collateral occlusions. After a mean duration of 15.4 ± 12.7 months, 16 patients had interventional catheterization consisting of 14 balloon dilatations, 12 stent implantations and 16 collateral occlusions. At a mean age of 2.7 ± 1.9 years, complete repair was performed in 31 patients within 1.2 ± 0.6 years of the palliation with 1 hospital death. Twenty-two patients had concomitant PA angioplasty. The estimated complete repair rate was 60.1 ± 7.1% ∼3 years after the palliation by the Kaplan-Meier method. During a mean follow-up of 2.8 ± 1.3 years, 49.3% (33/67) of the patients had PA reintervention. Pulmonary stenosis requiring angioplasty at palliation is associated with PA reintervention (P = 0.003). The actuarial survival rate for the overall population was 93.8 ± 3.0% at 5 years after the placement of an RV-PA connection. CONCLUSIONS The multistage strategy consisting of a RV-PA connection, MAPCA closure and PA angioplasty is effective in rehabilitating the hypoplastic PA in patients with pulmonary atresia, VSD and hypoplastic pulmonary arteries. However, PA reinterventions may be required in specific patients.

Biventricular repair for double outlet right ventricle with non-committed ventricular septal defect

OBJECTIVES Outcomes of biventricular repair for patients with double outlet right ventricle and non-committed ventricular septal defect (DORVncVSD) are not well defined. We aim to report our experience with biventricular repair of this anomaly in proposing an original surgical management that simplifies the anatomical correction. METHODS From January 2005 to December 2013, 75 consecutive patients with DORVncVSD who had undergone biventricular repair in our institution were retrospectively included. The patients were divided into 2 groups: 40 patients in Group A had the ventricular septal defect rerouted to the aorta, and 35 patients in Group B had the ventricular septal defect rerouted to the pulmonary artery. Concomitant tricuspid procedures, conal resection and ventricular septal defect enlargement were used to favour intracardiac tunnel geometry. RESULTS Five types of biventricular repair and 16 concomitant procedures were performed. Mean age at biventricular repair was 2.2 ± 2.0 years. There were 6 (8.0%) early deaths and 4 (6.1%) early intracardiac baffle obstructions. During the 4.1 ± 4.0 years follow-up, 3 (4.3%) late deaths occurred with an 87.1% estimated overall survival at 5 years (early deaths included). Six late-onset intracardiac tunnel obstructions were noted and three of them required reoperation. Comparing the 2 groups, Group A patients have more late-onset (6 in Group A vs 0 in Group B, P = 0.026) and overall tunnel obstructions (10 in Group A vs 0 in Group B, P = 0.001). Concomitant tricuspid procedures significantly reduced intracardiac obstruction (0 in 16 vs 10 in 24, P = 0.003) without development of any tricuspid regurgitation and stenosis. CONCLUSIONS Using appropriate intracardiac tunnel establishment strategy and techniques, biventricular repair of DORVncVSD is feasible with encouraging outcomes. Concomitant tricuspid procedures can reduce intracardiac tunnel geometry without increase of mortality and morbidity.

Histidine-Tryptophan-Ketoglutarate Solution With Added Ebselen Augments Myocardial Protection in Neonatal Porcine Hearts Undergoing Ischemia/Reperfusion

Whether modified histidine-tryptophan-ketoglutarate (HTK) solution offers myocardial protection to newborn heart has not been documented. The purpose of this study was to compare myocardial protection using HTK added by ebselen with HTK in a piglet model of cardiopulmonary bypass (CPB). Fifteen piglets were randomly assigned to three groups: the control group (C group, n = 5), HTK solution group (HTK group, n = 5), and HTK added by 10 nM ebselen group (HTK+E group, n = 5). Animals in the two experimental groups were placed on hypothermic CPB, after which the ascending aorta had been clamped for 2 h. The control animals underwent normothermic CPB without cardiac arrest. Myocardial antioxidant activities, myocytes apoptosis and mitochondrial structures, as well as the release of cytochrome c and the expression of Bax, Bcl-2, and HSP72 protein in myocardium were measured. Increased myocardial superoxide dismutase (SOD) and Mn-SOD activities, decreased TUNEL-positive cells, and reduced release of cytochrome c were noted in the HTK+E group compared with those in the HTK group (P = 0.021, P = 0.020, P = 0.045, and P = 0.010, respectively). The Bax/Bcl-2 ratio in the HTK group was significantly higher than that in the C group (P = 0.024). The expression of HSP72 protein and mRNA in the HTK+E group was higher than that in the HTK group (P = 0.039 and P = 0.035, respectively). Mitochondrial score under electron microscope in the HTK+E group was lower than that in the HTK group (P = 0.047). Improved antioxidant defense, reduced myocytes apoptosis, and better preserved mitochondrial structure were observed in the HTK+E group. Ebselen added to HTK provides better myocardioprotection to HTK solution for the neonatal heart.

Hybrid balloon valvuloplasty through the ascending aorta via median sternotomy in infants with severe congenital valvular aortic stenosis: feasibility of a new method

OBJECTIVES To evaluate a novel hybrid balloon valvuloplasty procedure for severe congenital valvular aortic stenosis in low-weight infants, performed through the ascending aorta via median sternotomy. METHODS Eighteen infants (<90 days of age) with severe congenital aortic stenosis were included in this study. Hybrid balloon valvuloplasty procedures were performed in a hybrid operating room. Patients were followed up at 3 months, 6 months, 1 year and then annually following the procedure. RESULTS The hybrid balloon valvuloplasty procedure was successful in all patients. Eight patients were successfully rescued from left ventricular systolic dysfunction by cardiac compression under direct vision. The aortic valve pressure gradient decreased from 80.3 ± 20.8 mmHg preoperatively to 16.0 ± 3.6 mmHg immediately postoperatively (P < 0.001). None of the patients developed significant aortic insufficiency. The fluoroscopy time was 6.2 ± 2.9 min. Intraoperative blood transfusions and pacing were not required. The patients were all alive and healthy at the end of the follow-up period (mean 21.3 months; range 3-41 months), and the aortic valve pressure gradient remained low (21.7 ± 5.3 mmHg). Reintervention was not required in any of the patients. CONCLUSIONS Hybrid balloon valvuloplasty through the ascending aorta via median sternotomy is an effective and safe procedure for infants with severe congenital aortic stenosis.

Which is the better option during neonatal cardiopulmonary bypass: HTK solution or cold blood cardioplegia?

The optimal myocardial protection strategy for newborns/infants undergoing congenital heart surgery remains controversial. The purpose of this study was to compare myocardial protection using histidine-tryptophan-ketoglutarate (HTK) and cold blood cardioplegia in a neonatal piglet model. Twenty-one piglets were randomized to three groups: the control group (C group, n = 7), a single dose of HTK group (H group, n = 7), and multidose cold blood cardioplegia group (B group, n = 7). Animals in the two experimental groups were placed on hypothermic cardiopulmonary bypass, after which the ascending aorta was clamped for 2 hours. Immediately after declamping, both the difference between arterial and coronary sinus blood lactate concentrations and the oxygen extraction did not differ between the H group and the B group. At 3 hours after declamping, rise in serum troponin-T and creatine kinase isoenzyme MB levels showed no significant differences between the H group and the B group (p = 0.735 and p = 0.103, respectively). No significant differences were noted in the myocardial lactate content, ATP content, and histopathological score between the H group and the B group (p = 0.810, p = 0.158, and p = 0.399, respectively). Transfusion requirement in the B group was significantly more than that in the H group (p = 0.003). HTK solution provides equivalent myocardial protection to multidose cold blood cardioplegia for the neonatal heart with less transfusion requirement.

Effects of pulmonary artery perfusion with urinary trypsin inhibitor as a lung protective strategy under hypothermic low-flow cardiopulmonary bypass in an infant piglet model

Objective: This study aimed to evaluate the effects of pulmonary artery perfusion with a urinary trypsin inhibitor (UTI) as a lung protective strategy in order to provide an experimental basis for immature lung clinical protective strategies on deep hypothermia with low-flow (DHLF) cardiopulmonary bypass (CPB)-induced pulmonary injury in an infant piglet model. Methods: The piglets (n=15), aged 18.7±0.3 days, weight 4.48±0.21kg, were randomly divided into 3 groups, with 5 piglets in each group: the control group, the pulmonary artery perfusion without UTI group (Group P) and the pulmonary artery perfusion with UTI group (Group U). The levels of the cytokines tumour necrosis factor-α, myeloperoxidase, malondialdehyde and interleukin-10 (TNF-α, MPO, MDA and IL-10) in pulmonary venous serum and lung tissue and the activity of NF-kappa B in lung tissue were measured by enzyme-linked immunosorbent assay (ELISA) and electrophoresis mobility shift assay (EMSA), respectively. Results: After DHLF-CPB, all of the piglets demonstrated a state of lung injury as a deterioration of lung function indices, lung injury scores, pulmonary ultrastructure changes, expression of TNF-α, MPO, MDA and IL-10 and the activities of nuclear factor-kappa B (NF-κB), while pulmonary artery perfusion with UTI significantly ameliorated lung function and histopathological changes, with greatly decreased serum levels of TNF-α and MPO compared to the other two groups. Also, we found an increase in the level of IL-10 in Group U lungs compared with that in Group P lungs, which correlated with a strong inhibition in the activity of NF-κB. Conclusion: Pulmonary artery perfusion with UTI ameliorated the DHLF-induced immature pulmonary injury in the lungs via a reduction of pro-inflammatory cytokine expression and up-regulated levels of IL-10 by inhibiting the activity of NF-κB.