Objectives In this study, with the use of computational fluid dynamics, we evaluate the postoperative hemodynamic performance of the first cohort of patients undergoing a handcrafted Y-graft Fontan ...procedure and validate simulation predictions of hepatic blood flow distribution against in vivo clinical data. Methods An 18-12 × 2–mm handcrafted Y-graft modification of the Fontan procedure was performed in 6 patients. Early (at the time of discharge) and 6-month postoperative 3-dimensional magnetic resonance imaging data were collected. Patient-specific models were constructed for flow simulations. Results Hepatic blood flow distribution varied among patients. Lung perfusion data (n = 3) showed good agreement with simulations. Postoperative asymmetry in hepatic blood flow distribution was reduced 6 months postoperatively. In 1 patient, low wall shear stress was found in the left limb of the Y-graft, corresponding to the location of subsequent thrombosis in the patient. Conclusions The credibility and accuracy of simulation-based predictions of postoperative hepatic flow distribution for the Fontan surgery have been validated by in vivo lung perfusion data. The performance of the Y-graft design is highly patient-specific. The anastomosis location is likely the most important factor influencing hepatic blood flow distribution. Although the development of thrombosis is multifactorial, the occurrence in 1 patient suggests that simulations should not solely consider the hepatic blood flow distribution but also aim to avoid low wall shear stress in the limbs.
Objectives The objective of this work is to evaluate the hemodynamic performance of a new Y-graft modification of the extracardiac conduit Fontan operation. The performance of the Y-graft design is ...compared to two designs used in current practice: a t-junction connection of the venae cavae and an offset between the inferior and superior venae cavae. Methods The proposed design replaces the current tube grafts used to connect the inferior vena cava to the pulmonary arteries with a Y-shaped graft. Y-graft hemodynamics were evaluated at rest and during exercise with a patient-specific model from magnetic resonance imaging data together with computational fluid dynamics. Four clinically motivated performance measures were examined: Fontan pressures, energy efficiency, inferior vena cava flow distribution, and wall shear stress. Two variants of the Y-graft were evaluated: an “off-the-shelf” graft with 9-mm branches and an “area-preserving” graft with 12-mm branches. Results Energy efficiency of the 12-mm Y-graft was higher than all other models at rest and during exercise, and the reduction in efficiency from rest to exercise was improved by 38%. Both Y-graft designs reduced superior vena cava pressures during exercise by as much as 5 mm Hg. The Y-graft more equally distributed the inferior vena cava flow to both lungs, whereas the offset design skewed 70% of the flow to the left lung. The 12-mm graft resulted in slightly larger regions of low wall shear stress than other models; however, minimum shear stress values were similar. Conclusions The area-preserving 12-mm Y-graft is a promising modification of the Fontan procedure that should be clinically evaluated. Further work is needed to correlate our performance metrics with clinical outcomes, including exercise intolerance, incidence of protein-losing enteropathy, and thrombus formation.
Anomalous aortic origin of a coronary artery (AAOCA) is a rare congenital heart defect that has been associated with myocardial ischemia and sudden death. Controversies exist regarding the diagnosis, ...treatment, and long-term recommendations for patients with AAOCA. The purpose of this study is to evaluate the medium-term results of surgical repair for AAOCA.
From January 1999 through August 2010, 50 patients underwent surgical repair of AAOCA. The median age at surgery was 14 years (range, 5 days to 47 years). Thirty-one patients had the right coronary originate from the left sinus of Valsalva, 17 had the left coronary originate from the right sinus, and 2 had an eccentric single coronary ostium. Twenty six of the 50 patients had symptoms of myocardial ischemia preoperatively, and 14 patients had associated congenital heart defects. Repair was accomplished by unroofing in 35, reimplantation in 6, and pulmonary artery translocation in 9.
There was no operative mortality. The median time of follow-up has been 5.7 years. Two patients were lost to follow-up, and 1 patient required heart transplantation 1 year after AAOCA repair. In the remaining 47 postoperative patients, all have remained free of cardiac symptoms and no one has experienced a sudden death event.
The surgical treatment of AAOCA is safe and appears to be highly effective in eliminating ischemic symptoms. These medium-term results are encouraging and suggest that many patients may be able to resume normal activities.
One anatomic variant of pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals (PA/VSD/MAPCAs) is characterized by the absence of intrapericardial pulmonary arteries. ...This anatomy obviates the possibility of incorporating the pulmonary arteries for reconstruction or palliative procedures. The purpose of this study was to evaluate the surgical results in patients undergoing repair of PA/VSD/MAPCAs with absent pulmonary arteries.
This was a retrospective review of 35 patients who underwent surgical repair of PA/VSD/MAPCAs with absent pulmonary arteries between 2007 and 2014. The median age at the time of surgery was 3.4 months, and the median weight was 4.9 kg. All patients underwent unifocalization of MAPCAs, with an average of 3.5 ± 1.4 MAPCAs per patient.
Twenty-eight of the 35 patients (80%) underwent complete single-stage surgical repair, including unifocalization of MAPCAs, VSD closure, and right ventricle to pulmonary artery conduit. After complete repair, the average right ventricular to aortic pressure ratio was 0.33 ± 0.07. There were no deaths in this subgroup. Seven patients (20%) were not deemed suitable candidates for VSD closure after their unifocalization procedure, and therefore underwent palliation with a central shunt. There was 1 operative death and 1 interim death. Three patients have subsequently undergone complete repair, and 2 are awaiting further evaluation and treatment.
The majority of patients with PA/VSD/MAPCAs and absent pulmonary arteries can undergo complete single-stage repair with satisfactory postoperative hemodynamics. These results suggest that unifocalization of MAPCAs can provide a reasonable pulmonary vascular bed in the absence of intrapericardial pulmonary arteries.
Home monitoring program reduces interstage mortality after the modified Norwood procedure Siehr, Stephanie L., MD; Norris, Jana K., NP; Bushnell, Julie A., NP ...
Journal of thoracic and cardiovascular surgery/The Journal of thoracic and cardiovascular surgery/The journal of thoracic and cardiovascular surgery,
02/2014, Volume:
147, Issue:
2
Journal Article
Peer reviewed
Open access
Background From 2002 to 2005, the interstage mortality after a modified Norwood procedure was 7% in our program. An interstage home monitoring program (HMP) was established to identify Norwood ...procedure patients at increased risk of decompensation and to reduce interstage mortality. Methods Results of the first 5 years of the Norwood HMP were reviewed retrospectively. Interstage was defined as the time between Norwood hospital discharge and admission for second stage surgical palliation. In the HMP, families documented oxygen saturation, heart rate, weight, and feedings daily. Nurse practitioners called each family at least weekly, and when issues arose, action plans were determined based on symptom severity. Results Between October 2005 and October 2010 there were 46 Norwood procedure patients who survived to hospital discharge. All were enrolled in the HMP. Forty-five patients had a Norwood procedure with right ventricle to pulmonary artery conduit, and 1 patient had a modified Blalock-Taussig shunt. Interstage survival was 100%. Nineteen patients (41%) were admitted interstage; 5 patients were admitted twice, 1 patient was admitted 4 times. Seventeen patients (37%) required interstage interventions. Eight patients (17%) required major interventions: conduit stenting, aortic arch balloon angioplasty, emergent shunt, or early Glenn surgery. Minor interventions included supplemental oxygen, blood transfusion, intravenous hydration, diuresis, anti-arrhythmic therapy, or feeding adjustments. Conclusions In the first 5 years of the HMP, all infants discharged after a modified Norwood procedure survived the interstage period. The HMP altered clinical management in 37% of patients. Home monitoring of oxygen saturation, heart rate, weight, and feedings, along with comprehensive care coordination, allowed timely interventions and reduced interstage mortality from 7% to 0%.
Objective This study was undertaken to assess the risks and benefits of the double-switch operation using a hemi-Mustard atrial switch procedure and the bidirectional Glenn operation for congenitally ...corrected transposition of the great arteries. To avoid complications associated with the complete Senning and Mustard procedures and to assist right-heart hemodynamics, we favor a modified atrial switch procedure, consisting of a hemi-Mustard procedure to baffle inferior vena caval return to the tricuspid valve in conjunction with a bidirectional Glenn operation. Methods Between January 1994 and September 2009, anatomic repair was achieved in 48 patients. The Rastelli–atrial switch procedure was performed in 25 patients with pulmonary atresia and the arterial–atrial switch procedure was performed in 23 patients. A hemi-Mustard procedure was the atrial switch procedure for 70% (33/48) of anatomic repairs. Results There was 1 in-hospital death after anatomic repair. There were no late deaths or transplantation. At a median follow-up of 59.2 months, 43 of 47 survivors are in New York Heart Association class I. Bidirectional Glenn operation complications were uncommon (2/33), limited to the perioperative period, and seen in patients less than 4 months of age. Atrial baffle–related reoperations or sinus node dysfunction have not been observed. Tricuspid regurgitation decreased from a mean grade of 2.3 to 1.2 after repair ( P = .00002). Right ventricle–pulmonary artery conduit longevity is significantly improved. Conclusions We describe a 15-year experience with the double-switch operation using a modified atrial switch procedure with favorable midterm results. The risks of the hemi-mustard and bidirectional Glenn operation are minimal and are limited to a well-defined patient subset. The benefits include prolonged conduit life, reduced baffle- and sinus node–related complications, and technical simplicity.
Objectives A novel Y-shaped baffle has been proposed for the Fontan operation with promising initial results. However, previous studies have relied either on idealized models or a single ...patient-specific model. The objective of this study is to comprehensively compare the hemodynamic performance and hepatic blood flow distribution of the Y-graft Fontan baffle with 2 current designs using multiple patient-specific models. Methods Y-shaped and tube-shaped grafts were virtually implanted into 5 patient-specific Glenn models forming 3 types of Fontan geometries: Y-graft, T-junction, and offset. Unsteady flow simulations were performed at rest and at varying exercise conditions. The hepatic flow distribution between the right and left lungs was carefully quantified using a particle tracking method. Other physiologically relevant parameters such as energy dissipation, superior vena cava pressure, and wall shear stress were evaluated. Results The Fontan geometry significantly influences the hepatic flow distribution. The Y-graft design improves the hepatic flow distribution effectively in 4 of 5 patients, whereas the T-junction and offset designs may skew as much as 97% of hepatic flow to 1 lung in 2 cases. Sensitivity studies show that changes in pulmonary flow split can affect the hepatic flow distribution dramatically but that some Y-graft and T-junction designs are relatively less sensitive than offset designs. The Y-graft design offers moderate improvements over the traditional designs in power loss and superior vena cava pressure in all patients. Conclusions The Y-graft Fontan design achieves overall superior hemodynamic performance compared with traditional designs. However, the results emphasize that no one-size-fits-all solution is available that will universally benefit all patients and that designs should be customized for individual patients before clinical application.
Background ERCP experience in pancreatic disorders in children is limited. Objective This study evaluated the utility and efficacy of ERCP in children with pancreatic diseases at a tertiary care ...referral center. Patients and Settings Consecutive patients 18 years of age and younger who underwent ERCP for pancreatic diseases from January 2010 to June 2011 were identified. Indications, findings, interventions, adverse events, and outcomes were recorded. Results A total of 221 ERCPs were performed in 172 children (102 boys, mean ± standard deviation age 13.8 ± 3.2 years, 157 therapeutic). A total of 143 children (83.1%) had chronic pancreatitis (CP), 19 (11%) had recurrent acute pancreatitis (RAP), and 10 (5.8%) had acute pancreatitis (AP). Indications included pain (153, 89.4%), pancreatic fistula (11, 6.3%), symptomatic pseudocyst (4, 2.3%), and jaundice (3, 1.7%). In chronic pancreatitis patients, findings included a dilated and irregular main pancreatic duct (92, 64.3%), pancreatic duct (PD) calculi (76, 53%), dominant PD stricture (23, 16%), PD leak (7, 4.9%), pancreas divisum (35, 24.5%), and common bile duct (CBD) stricture (3, 2%). Therapeutic procedures included major papilla sphincterotomy (93, 65%), minor papilla sphincterotomy (32, 22.3%), PD stenting (77, 53.8%), and CBD stenting (3, 2.2%). PD stones larger than 5 mm were retrieved endoscopically after 57 extracorporeal shock wave lithotripsy sessions in 50 patients (34.9%). In patients with RAP, 6 (31.5%) had complete and 1 partial pancreas divisum. All underwent minor papillotomy. In patients with AP, 4 (40%) had stenting for PD leak, 2 (20%) underwent CBD clearance for biliary pancreatitis, and 4 (40%) had transpapillary pseudocyst drainage. During 13 ± 4.7 months (range 6-22 months) of follow-up, improvement of symptoms was seen in 143 of 172 (83%) patients. Procedure-related adverse events were seen in 8 (4.7%) patients. Limitations Retrospective study. Conclusion ERCP is a safe therapeutic option for pancreatic disorders in children.
Objectives Peripheral pulmonary artery stenosis is a rare congenital heart defect frequently found in association with Williams and Alagille syndromes. Controversy exists regarding the optimal ...treatment of peripheral pulmonary artery stenosis, with most centers favoring catheter-based interventions. In contrast, we have preferentially used surgical reconstruction of peripheral pulmonary artery stenosis. The purpose of the present study was to review our experience with surgical reconstruction of peripheral pulmonary artery stenosis. Methods We performed a retrospective review of patients who underwent surgical reconstruction of peripheral pulmonary artery stenosis. A total of 16 patients were identified: 7 had Williams syndrome, 6 had Alagille syndrome, and 3 had no identifiable syndrome. Detailed pulmonary angiography was performed in all patients to define stenoses at the main, branch, lobar, and segmental arterial levels. The mean preoperative right ventricular/left ventricular pressure ratio was 0.88 ± 0.07. The surgical approach was a median sternotomy with cardiopulmonary bypass. All peripheral stenoses were augmented with pulmonary artery homograft tissue. The median age at surgery was 14 months, and concomitant procedures were performed in 9 of the 16 patients. Results There was 1 operative mortality (6%). The mean right ventricular/left ventricular pressure ratio decreased to 0.40 ± 0.04 postoperatively ( P < .005), representing a 55% reduction compared with the preoperative values. The patients were followed up for a median of 5 years. No late mortality occurred and reoperation was not required. Conclusions The data have demonstrate that this comprehensive surgical approach to the treatment of peripheral pulmonary artery stenosis was associated with low early and no late mortality. Surgical reconstruction of the peripheral pulmonary artery stenosis resulted in a significant decrease in right ventricular pressure. We hypothesize that this reduction in right ventricular pressures will confer a long-term survival advantage for this cohort of patients.
There are conflicting reports regarding the importance of mitral stenosis and aortic atresia as a risk factor for Norwood mortality. This study reviews outcomes of this anatomic subgroup at our ...institution and examines the utility of preoperative cardiac catheterization and its correlation with clinical outcomes and pathology findings.
This is a single-center, retrospective review of hypoplastic left heart syndrome patients who underwent modified Norwood operation between October 2005 and May 2013.
Fourteen of 74 hypoplastic left heart syndrome patients (19%) had mitral stenosis and aortic atresia. Operative mortality for MS/AA was 29% versus 7% for all other hypoplastic left heart syndrome anatomic subgroups (p = 0.04). Although only 19% of the entire cohort, the mitral stenosis and aortic atresia subgroup constituted 50% of the total operative mortality and the only interstage deaths. Autopsies support myocardial ischemia as the mechanism of death. Although preoperative angiography defined the presence of ventriculo-coronary connections, it did not clearly risk stratify patients in regard to operative mortality.
Mitral stenosis and aortic atresia is a risk factor for perioperative myocardial ischemia and mortality. Further exploration of myocardial reserve is warranted.
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