Pulmonary Artery Growth Research Articles

Pulmonary atresia with ventricular septal defect and tetralogy of Fallot: transannular path augmentation versus systemic to pulmonary artery shunt for first-stage palliation.

Pulmonary atresia with ventricular septal defect and severe tetralogy of Fallot require a palliative procedure for pulmonary artery rehabilitation. For first-stage palliation, two main surgical options are still debated: right ventricle to pulmonary artery connection and modified Blalock-Taussig shunt. We compared the clinical outcomes of the two procedures. From 1995 to 2018, 88 patients needed palliation (pulmonary atresia with ventricular septal defect n = 47; tetralogy of Fallot n = 41). Among these patients, 70 modified Blalock-Taussig shunt and 18 transannular path augmentation were performed before 6 months of age. Using a 1:1 propensity score match analysis, 20 patients were included in the analysis. The primary outcome was in-hospital mortality and pulmonary artery growth. After matching, the pre-operative Nakata was smaller in transannular path augmentation 54 ± 24 mm2/m2 than modified Blalock-Taussig shunt 109 ± 31 mm2/m2 (p < 0.001). The age and weight were similar (p = 0.31 and p = 0.9, respectively). There was no difference in in-hospital mortality (p = 0.3). The Nakata index before biventricular repair and delta Nakata were smaller in modified Blalock-Taussig shunt group (206 ± 80 mm2/m2, 75 ± 103 mm2/m2) than transannular path augmentation (365 ± 170 mm2/m2, 214 ± 165 mm2/m2; p = 0.03; p < 0.001). Median time to biventricular repair was similar (p = 0.46). The rate of interstage reintervention was similar (p = 0.63). The transannular path augmentation is better for the rehabilitation of the native pulmonary artery. Despite a smaller pulmonary artery, right ventricle to pulmonary artery connection is equivalent to modified Blalock-Taussig shunt for rate of biventricular repair and time to biventricular repair.

Serial assessment of somatic and cardiovascular development in patients with single ventricle undergoing Fontan procedure

BackgroundThe palliation of patients with single ventricle (SV) undergoing Fontan procedure led to improved long-term survival but is still limited due to cardiovascular complications. The aim of this study was to describe the somatic and cardiovascular development of Fontan patients until adolescence and to identify determining factors. MethodsWe retrospectively assessed somatic growth, vascular growth of pulmonary arteries, and cardiac growth of the SV and systemic semilunar valve from 0 to 16 years of age using transthoracic echocardiography. The Doppler inflow pattern of the atrioventricular valve was quantified by E-, A-wave and E/A ratio. All data were converted to z-scores and analyzed using linear mixed effect models to identify associations with age at Fontan procedure, gender, and ventricular morphology. Results134 patients undergoing Fontan procedure at a median age of 2.4 (IQR 2.12 to 2.8) years were analyzed. A catch-up of somatic growth after Fontan procedure until school age was found, with lower body height and weight z-scores in male patients and patients with systemic right ventricles. An early time of Fontan procedure was favorable for somatic growth, but not for vascular growth. Cardiac development indicated a decrease of SV end-diastolic diameter z-score until adolescence. Despite a trend towards normalization, E-wave and E/A ratio z-scores were diminished over the entire period. ConclusionsThere is a catch-up growth of somatic, vascular and cardiac parameters after Fontan procedure, which in our cohort depends on the time of Fontan procedure, ventricular morphology, and gender. Beside other factors, diastolic function of the SV remains altered.

Results of Less Than 5-mm Right Ventricle-Pulmonary Artery Conduits in Single Ventricle Palliation

Our programmatic approach to single ventricle (SV) neonatal palliation has evolved to using smaller-size right ventricle to pulmonary artery (RV-PA) conduits for pulmonary blood flow. Therefore, we sought to compare the early outcomes of less than 5-mm versus 5-mm RV-PA conduits in SV patients undergoing neonatal palliation. We performed a retrospective review of SV patients who had neonatal palliation with either a less than 5-mm or 5-mm RV-PA connection, constructed using a waterproof, breathable fabric membrane graft (Gore-Tex, Flagstaff, AZ). Data before, during, and after surgery were analyzed using SPSS software. A total of 26 patients in group 1 (n= 11; <5 mm) and group 2 (n= 15; 5 mm) were operated on, with a mean follow-up of 13 months. Statistical differences (P ≤ .05) were noted with renal near-infrared spectroscopy (mean, 56 versus 44), and oxygen saturation at discharge (mean, 80% versus 85%) in groups 1 and 2, respectively. We found no significant difference in patient weight, peak lactate, cerebral near-infrared spectroscopy, length of intubation, length of hospitalization, or need for RV-PA conduit intervention after stage 1 along with age, branch PA sizes, or need for PA plasty at bidirectional Glenn between groups. Our early results of less than 5-mm conduits support further exploration into the tailoring of the RV-PA conduit size for each patient. A smaller-diameter conduit may improve systemic cardiac output and net oxygen delivery. Larger patient cohorts and longer follow-up with assessment of pulmonary artery growth are warranted to guide clinical practice.

Evaluation of the Growth of Central Pulmonary Arteries Following Patent Ductus Arteriosus Stenting in Patients with Duct Dependent Pulmonary Circulation

Pulmonary arteries' (PAs) growth can be promoted by stenting of patent ductus arteriosus (PDA). This may result in better angle between the PDA and the PAs, allowing improved growth. In this study, we sought to evaluate the effect of PDA stenting on the growth of the pulmonary arteries by comparing their dimensions pre-stenting to their dimensions in the pre-second stage operations in patients with congenital heart diseases-duct-dependent pulmonary (CHD-DDP) circulation. Between January 2015 and December 2016, 58 neonates with CHD-DDP circulation underwent transcatheter PDA stenting and had evaluation of PAs growth before the second stage. Various parameters [Pre-branching right and left pulmonary artery (RPA, LPA) diameters, their Z scores, LPA/RPA ratio, McGoon's ratio and Nakata index] were recorded and compared pre-stenting and pre-second stage. The evaluation was done using catheterization or multislice computed tomography (MSCT). PDA stenting was successful in 49 patients out of 58 (84.5%) patients with an age of 13.5 ± 10.4days and a weight of 2.9 ± 0.5kg. Twenty-two (44.9%) patients had complex CHD-DDP, 14 (28.6%) patients had PA/IVS and 13 (26.5%) patients had PA/VSD. Pre-second stage RPA, LPA diameters and their Z scores increased significantly (RPA increased from 0.36 ± 0.05cm to 0.60 ± 0.11cm, P < 0.001, RPA Z-score increased from -1.29 ± 0.91 to 0.81 ± 0.18, P < 0.001; LPA increased from 0.34 ± 0.06cm to 0.58 ± 0.10cm, P < 0.001, LPA Z-score increased from -1.17 ± 0.86 to 0.97 ± 0.48, P < 0.001). McGoon's ratio increased significantly from 1.20 ± 0.11 to 1.61 ± 0.15 (P < 0.001). Nakata index increased from 105.94 ± 33.53 to 183.48 ± 40.58 mm2/m2 (P < 0.001). However, LPA/RPA ratio did not change (0.96 ± 0.05 and 0.98 ± 0.16, P = 0.288). PDA stenting is effective in promoting the global and the individual pulmonary artery growth in congenital heart diseases with duct-dependent pulmonary circulation. In this study, we presented our experience with this approach in 2 tertiary care centers in the DELTA region of Egypt. PDA stenting, generally, showed symmetric growth of the pulmonary arteries with comparable results to the international figures.

Growth Factor Midkine Aggravates Pulmonary Arterial Hypertension via Surface Nucleolin

Pulmonary arterial hypertension (PAH) is a progressive fatal disease caused by pulmonary arterial remodeling. Midkine regulates cell proliferation and migration, and it is induced by hypoxia, but its roles in pulmonary arterial remodeling remain unclear. Serum midkine levels were significantly increased in PAH patients compared with control patients. Midkine expression was increased in lungs and sera of hypoxia-induced PAH mice. Hypoxia-induced pulmonary arterial remodeling and right ventricular hypertrophy were attenuated in midkine-knockout mice. Midkine-induced proliferation and migration of pulmonary arterial smooth muscle cells (PASMC) and epidermal growth factor receptor (EGFR) signaling were significantly increased under hypoxia, which also induced cell-surface translocation of nucleolin. Nucleolin siRNA treatment suppressed midkine-induced EGFR activation in vitro, and nucleolin inhibitor AS1411 suppressed proliferation and migration of PASMC induced by midkine. Furthermore, AS1411 significantly prevented the development of PAH in Sugen hypoxia rat model. Midkine plays a crucial role in PAH development through interaction with surface nucleolin. These data define a role for midkine in PAH development and suggest midkine-nucleolin-EGFR axis as a novel therapeutic target for PAH.

Impact of ductal stenting on pulmonary artery reconstruction in patients with duct-dependent congenital heart diseases-an institutional experience.

This study aims to review our institutional experience of ductal stenting (DS) on the growth of pulmonary arteries (PAs) and surgical outcomes of PA reconstruction in this subset of patients. This is a retrospective study done in neonates and infants up to 3 months of age with duct-dependent pulmonary circulation who underwent DS from January 2014 to December 2015. Post-stenting PA growth, surgical outcomes of PA reconstruction, post-surgical re-interventions, morbidity and mortality were analysed. During the study period, 46 patients underwent successful DS, of whom 38 underwent presurgery catheterization and definite surgery. There was significant growth of PAs in these patients. Biventricular repair was done in 31 patients while 7 had univentricular palliation. Left PA augmentation was required in 13 patients, and 10 required central PA augmentation during surgery. The mean follow-up period post-surgery was 4.5 ± 1.5 years. No significant postoperative complications were seen. No early or follow-up post-surgery mortality was seen. Four patients required re-interventions in the form of left PA stenting based on the echocardiography or computed tomography evidence of significant stenosis. DS provides good short-term palliation and the growth of PAs. However, a significant number of stented patients require reparative procedure on PAs at the time of surgical intervention. Acquired changes in the PAs following DS may be the reason for reintervention following PA reconstruction.

Impact of stent of ductus arteriosus and modified Blalock-Taussig shunt on pulmonary arteries growth and second-stage surgery in infants with ductus-dependent pulmonary circulation.

IntroductionDucts-dependent pulmonary circulation is spectrum of congenital heart diseases that need urgent intervention to augment pulmonary blood. Systemic to pulmonary shunt is the classical surgical management. Stenting of ductus arteriosus emerged in the last 2 decades as an alternative plausible intervention.ObjectivesTo evaluate and compare the short and midterm effects of PDA stenting in compared to surgically placed shunt for augmentation of pulmonary blood flow looking to pulmonary artery (PA) branches growth, oxygen saturation and suitability for second stage repair.MethodsWe conducted this prospective study in Cardiac Surgical Intensive Care Unit. Cases were divided into “stent group” and “surgical shunt” group. Results were compared between two groups regarding oxygen saturation, mechanical ventilation duration, intensive care stay, mortality and morbidity. Growth of PA branches was assessed during follow up by echocardiograph. Nakata index score was calculated by angiogram before second stage surgery and was compared between both groups.Results43 patients were included. Forty-two cases were offered stent as initial management. 6/42 cases failed stenting (14%) and 3/42 (7%) required late BT shunt after PDA stenting. 10/43 cases ended up receiving BT shunt and were counted as “surgical shunt group”. Stent group (33 cases) needed less mechanical ventilation (2.08 ± 0.65 vs.7.8 ± 4 days with p = 0.014), and less ICU stay compared with surgical shunt group (6.2 ± 1.02 vs. 14 ± 4.5 days, P = 0.009). Both groups achieved similar growth of pulmonary artery branches (p = 0.6 for Z score of left pulmonary artery and P = 0.8 for Z score for right pulmonary artery). Although “stent group” reached second stage surgery with lower O2 saturation 67.6 ± 4.6 vs. 80 ± 4.2 in “surgical shunt” group with P value = 0.0002). Majority of patients in both groups had some PA distortion and needed surgical reconstruction in main pulmonary artery or in its main branches during second stage repair. 3 cases (7.1%) died soon post stenting versus none in surgical shunt group (p = value 0.57).ConclusionsIn neonates with ductus-dependent pulmonary circulation PDA stenting can be introduced as safe first possible option to augment pulmonary blood flow with good outcome and suitable preparation for second stage palliation.

Initial Experience in Chile with Stent Implantation in the Right Ventricle Outflow Tract in High-Risk Patients with Tetralogy of Fallot.

Tetralogy of Fallot (ToF) treatment is difficult in patients with surgical risk factors or unfavorable anatomy. Stent implantation in the right ventricular outflow tract (RVOT) is an option for these patients. We report our initial experience in Chile withRVOT stenting in patients with ToF. Retrospective and descriptive study conducted in three pediatric cardiovascular centers in Chile between 2012 and 2015, including all ToF patients with stent in the RVOT as first procedure. Clinical records, echocardiographic, interventional, and surgical reports were reviewed for demographics and information of RVOT and pulmonary arteries. 12 newborns with ToF were included (75% female). Median age was 20days (1-70) and mean weight was 2178g (1400-3414). Saturations increased after the procedure from 74.3% (55-88) to 88.5% (80-98%), (p < 0.01). No complications or mortality were related to interventions. Follow-up was 11months (7-36). Median right and left pulmonary arteries Z-score increased from - 4.0 (- 5.2 to - 0.3) and - 1.5 (- 4.8 to - 0.26) to + 0.53 (0.0 to 2.2) and + 1.1 (0.5 to 2.9), (p < 0.05), respectively. Nakata index increased from 63mm2/mm2 (35 to 143) to 162mm2/mm2 (107 to 197), (p < 0.05). Surgical repair was performed at a median of 4months (2-7). Transannular patch repair was necessary in all patientsand there wasno surgical mortality. RVOT stenting is a safe and useful option for patients with ToF and surgical risk factors or unfavorable anatomy. It increases the pulmonary blood flow, improving saturation and pulmonary artery growth as a bridge for surgical repair.

Hemodynamic Effects of Additional Pulmonary Blood Flow on Glenn and Fontan Circulation.

Additional pulmonary blood flow (APBF) can provide better pulsating blood flow and systemic arterial oxygen saturation, while low blood pulsation and low oxygen saturation are defects of the Fontan and Glenn procedure. Studying the hemodynamic effect of APBF is beneficial for clinical decisions. This study aimed to explore the effect on particle washout, as well as the differences among the sensitivities of both different hemodynamic parameters and different procedures to APBF. The patient-specific clinical datasets of a patient who underwent bilateral bidirectional Glenn (BBDG) with APBF were enrolled in this study, and using these datasets, Glenn- and Fontan-type artery models were reconstructed. A series of parameters, including the total caval flow pulsatility index (TCPI), indexed energy loss (iPL), wall shear stress (WSS), systemic arterial oxygen saturation (Satart), particle washout time (WOT), pressure in the rightsuperior vena cava (PRSVC), pulmonary flow distribution (PFD) and hepatic flow distribution (HFD), were computed from computational fluid dynamic (CFD) simulation to evaluate the hemodynamic effect of APBF. The result showed that APBF led to better iPL and Satart but worse PRSVC and heart load accompanied by a great impact on HFD, making hepatic flow easier to perfuse the side without MPA and APBF. The increase in the APBF rate also effectively results in larger flow pulsation, region velocity, and wall shear stress and lower WOT, and this effect may be more effective for patients with persistent left superior vena cava (PLSVC). However, APBF might have little effect on PFD. Furthermore, APBF might affect WOT, iPL and HFD more significantly than PRSVC and has a greater improvement effect in patients with poorer iPL and WOT. Moderate APBF is not only a measure to promote pulmonary artery growth and systemic arterial oxygen saturation but also an effective method against endothelial dysfunction and thrombosis. However, moderate APBF is patient-specific and should be determined based on hemodynamic preference that leads to desired patient outcomes, and care should be taken to prevent PRSVC and heart load from being too high as well as an imbalance in HFD.

Impact of intrapulmonary-artery septation to pulmonary vein obstruction for two-lung Fontan

Patients with unbalanced pulmonary artery (PA) growth and decreased unilateral pulmonary circulation are considered unsuitable candidates for the Fontan procedure. Following our previous study on the utility of intrapulmonary-artery septation for patients with PA hypoplasia, we investigated its use in patients with pulmonary venous obstruction (PVO). We recruited 42 patients who underwent intrapulmonary-artery septation for unilateral PA hypoplasia and/or PVO between 1998 and 2018 and classified them into no PVO or PVO group. We analysed overall survival, success of the Fontan procedure and data from catheterization and echocardiography. In PVO, we evaluated the functional lung area before the Fontan procedure and the relevance of this parameter to operative outcomes. The PVO and no-PVO group included 24 and 18 patients, respectively. One patient in the no-PVO and 6 patients in the PVO group died during follow-up; this difference was statistically significant (log-rank P = 0.040). In the no-PVO group, 15 (83%) patients achieved two-lung Fontan circulation. In the PVO group, 12 (50%) patients achieved two-lung Fontan circulation. Multivariate analysis revealed that functional lung area and shunt size [significantly larger in patients with functional lung area ≥50% in affected lung (P = 0.040)] were significant factors for successful two-lung Fontan procedure (P = 0.030). Intrapulmonary-artery septation may contribute to increase functional lung area after PVO release to establish two-lung Fontan circulation in patients with PVO who have unbalanced PA growth and/or decreased unilateral pulmonary circulation.

The effect of a valved small conduit on systemic ventricle–pulmonary artery shunt in the Norwood-type palliation

The aim of this study was to clarify the impact of valved systemic ventricle-pulmonary artery (SV-PA) shunt on outcomes after stage-1 Norwood-type palliation (NP) compared with the modified Blalock-Taussig shunt. Consecutive patients who underwent NP between 2003 and 2019 were enrolled. SV-PA shunts using the expanded polytetrafluoroethylene valved conduit were implanted in 18 patients (valved SV-PA group), and another 18 patients underwent modified Blalock-Taussig shunt during NP (modified Blalock-Taussig shunt group). All valved conduits were made in our institution in advance. No differences in baseline characteristics were found between the groups, except for shunt size. During a median 2.9 (interquartile range 0.4-6.4, maximum 14.2) years of follow-up, 8 (22.2%) patients died across both groups. There were no statistically significant differences in early mortality (5.5% vs 11.1%, P = 0.55) and overall survival rates at 5 years (80.8% vs 71.4%, P = 0.48) in the valved SV-PA and modified Blalock-Taussig shunt groups. No statistically significant difference was observed in the frequency of interventions between the groups (31% vs 33%, P = 1.0). At the time of the bidirectional Glenn procedure, the systemic ventricular end-diastolic volume index was significantly lower (84 ± 24 vs 106 ± 31 ml/m2, P = 0.05) and the ejection fraction was significantly greater (62 ± 8% vs 55 ± 9%, P = 0.03) in the valved SV-PA group. There was no statistically significant difference in the pulmonary artery index (228 ± 85 vs 226 ± 60 mm2/m2, P = 0.92). A valved SV-PA shunt using an expanded polytetrafluoroethylene valved conduit was associated with preserved ventricular function after NP and did not impair pulmonary artery growth by controlling pulmonary regurgitation.

Anterograde blood flow associated with Blalock-Taussig shunts does not modify pulmonary artery growth compared with Blalock-Taussig shunt alone

The difference between extreme Tetralogy of Fallot (T4F) and pulmonary atresia with ventricle septal defect (PA/VSD) is the anterograde pulmonary blood flow. It is speculated that the association of modified Blalock-Taussig shunt (mBTs) and additional pulmonary blood flow favours shunt thrombosis but promotes better pulmonary arterial (PA) growth. This study sought to compare (PA) growth after mBTs shunt between T4F and AP/VSD. From 1995 to 2018, 79 mBTs were performed in infants (< 1 years), 45 for T4F and 34 for AP/VSD. Using a 1:1 propensity score match analysis, 38 patients were included ( n = 19 in each group). The primary outcome was operative mortality, mBTs thrombosis, and PA growth. After matching, the preoperative Nakata was similar (101 ± 8 mm 2 /m 2 in T4F; 106 ± 8 in AP/VSD P = 0.75 ). The age and weight were similar (24,3 ± 5 days, 3.3 ± 0.5 kg in T4F; 24,15 ± 4, 3.3 ± 0.9 in AP/VSD P = 0.84 and P = 0.77 respectively ). The mBTs size was similar (4.15 ± 0.5 mm in T4F; 4.3 ± 0.5 in PA/VSD P = 0.35). There was no difference in in-hospital mortality ( n = 0, in T4F; n = 2, 11% in AP/VSD, P = 0.14) and mBTs thrombosis (3,16% in T4F; 2,11% in AP/VSD, P = 0.18). The time to extubation tended to be longer in T4F (5 ± 1days vs. 2 ± 1 P = 0.06). The left and right PA diameter at time of biventricular repair were similar (7.5 ± 0.5 mm, 7 ± 0.2 in T4F; 8.1 ± 0.7 mm, 7 ± 1 in AP/VSD P = 0.43 and P = 0.78, Fig. 1 ) and the Nakata delta (112 ± 23 mm 2 /m 2 in T4F; 110 ± 17 in AP/VSD P = 0.78). Median time to complete repair was the same in the PA/VSD (12.26 [3.9-25] months) compared with T4F (9.7 [6.2–41.1] months) P = 0.87). The interstage reintervention were similar (3.16% in T4F; 4.22% in AP/VSD , P = 0.9 ). Anterograde blood flow with mBTs did not increase the risk of mBTs thrombosis. We could not show benefit of anterograde blood flow with mBTS versus mBTS for pulmonary arteries growth. Anterograde blood flow did increase the time to extubation, probably by increasing total pulmonary blood flow.

Choice of shunt type for the Norwood I procedure: does it make a difference?

This study aimed to compare pulmonary artery (PA) growth between patients who received a right ventricle-to-PA (RV-PA) shunt and those who received a modified Blalock-Taussig shunt (mBTS). All consecutive patients with hypoplastic left heart syndrome who underwent the Norwood I procedure between 2001 and 2017 were included in the study. Pre-stage 2 angiograms were analysed to measure the size of the PA. The Nakata index was calculated to estimate PA growth. The ratio of the right PA to left PA cross-sectional area (RPA/LPA) was used to calculate the difference in growth between the 2 branches. Study end points were shunt failure, shunt-related mortality and growth of the PAs. A total of 223 patients with hypoplastic left heart syndrome (RV-PA group = 137, mBTS group = 86) underwent the Norwood I procedure, and 186 patients (RV-PA n = 116, mBTS n = 70) achieved the stage 2 procedure. PA growth was better in patients with mBTS (Nakata index: RV-PA = 282, mBTS = 315 mm2/m2, P = 0.021). LPA growth was worse compared to RPA growth in both groups (RPA/LPA: RV-PA = 1.21, mBTS = 1.29, P = 1.0). Patients with RV-PA shunts experienced more frequent shunt stenosis compared to patients with mBTS (26 vs 2, P < 0.010). Freedom from shunt failure was 83.3 ± 3.2% and 94 ± 2% at 6 months in the RV-PA and mBTS groups, respectively (P = 0.003). PA growth is significantly better in patients who received an mBTS. Moreover, patients with an RV-PA shunt more frequently experienced shunt failure due to shunt stenosis. However, survival after the NW procedure is not shunt dependent and growth of the LPA is less pronounced than RPA, regardless of the shunt type.

Correction to: Comparison of Outcomes at Time of Superior Cavopulmonary Connection Between Single Ventricle Patients With Ductal-Dependent Pulmonary Blood Flow Initially Palliated With Either Blalock-Taussig Shunt or Ductus Arteriosus Stent: Results From the Congenital Catheterization Research Collaborative

HomeCirculation: Cardiovascular InterventionsVol. 12, No. 11Correction to: Comparison of Outcomes at Time of Superior Cavopulmonary Connection Between Single Ventricle Patients With Ductal-Dependent Pulmonary Blood Flow Initially Palliated With Either Blalock-Taussig Shunt or Ductus Arteriosus Stent: Results From the Congenital Catheterization Research Collaborative Free AccessCorrectionPDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessCorrectionPDF/EPUBCorrection to: Comparison of Outcomes at Time of Superior Cavopulmonary Connection Between Single Ventricle Patients With Ductal-Dependent Pulmonary Blood Flow Initially Palliated With Either Blalock-Taussig Shunt or Ductus Arteriosus Stent: Results From the Congenital Catheterization Research Collaborative Originally published19 Nov 2019https://doi.org/10.1161/HCV.0000000000000045Circulation: Cardiovascular Interventions. 2019;12:e000045In the article by Meadows et al, “Comparison of Outcomes at Time of Superior Cavopulmonary Connection Between Single Ventricle Patients With Ductal-Dependent Pulmonary Blood Flow Initially Palliated With Either Blalock-Taussig Shunt or Ductus Arteriosus Stent: Results From the Congenital Catheterization Research Collaborative,” which appeared in the October 2019 issue of the journal (Circ Cardiovasc Interv. 2019;12:e008110. doi: 10.1161/CIRCINTERVENTIONS.119.008110), corrections were needed.In the Results section of the Abstract the sentence “Preoperative hemodynamics and overall pulmonary atresia growth were similar, although right pulmonary artery growth was better with DAS (change in z-score: 1.57 versus 0.65, P=0.026)” should be “Preoperative hemodynamics and overall pulmonary artery growth were similar, although right pulmonary artery growth was better with DAS (change in z-score: 1.57 versus 0.65, P=0.026).”In the Conclusions section of the Abstract, the sentence “Both groups demonstrated good pulmonary atresia growth” should be “Both groups demonstrated good pulmonary artery growth.”Additionally, Figures 1 and 2 were incorrect. Figure 1 should have been Figure 2, and Figure 2 should have been Figure 1, and both were missing units of “(Months)” on the x axis.This correction has been made to the article, which is available at: https://www.ahajournals.org/doi/10.1161/CIRCINTERVENTIONS.119.008110. Previous Back to top Next FiguresReferencesRelatedDetails November 2019Vol 12, Issue 11 Advertisement Article InformationMetrics © 2019 American Heart Association, Inc.https://doi.org/10.1161/HCV.0000000000000045 Originally publishedNovember 19, 2019 PDF download Advertisement

Intermediate Outcomes of Staged Tetralogy of Fallot Repair.

The optimal surgical strategy for tetralogy of Fallot (TOF) repair in neonates and young infants requiring early surgical intervention remains controversial. Our surgical center follows the uniform strategy of a staged approach with initial systemic-to-pulmonary artery shunt the majority of time when early surgical intervention is required. We characterized a contemporary cohort of patients with TOF with pulmonary stenosis (PS) undergoing staged repair in order to determine the rate of pulmonary valve-sparing repair (PVSR), growth of the pulmonary valve annulus and pulmonary arteries, postoperative morbidity and mortality, and need for reintervention. We retrospectively studied patients with TOF/PS who underwent staged repair from 2000 to 2017. Surgical details, postoperative course, and reinterventions were noted. Echocardiographic measurements and Z-score values of pulmonary valve annulus, main pulmonary artery (MPA), right pulmonary artery (RPA), and left pulmonary artery (LPA) diameters were evaluated. Of the 59 patients with staged TOF/PS, PVSR was performed in 25 (42%). There was a 5% incidence of postoperative arrhythmia. The Z-scores of MPA, RPA, and LPA were significantly higher before complete repair when compared to before palliative shunt. The 5 and 10-year survival rates were both 93%, and the probability of freedom from reoperation at 5 and 10 years was 87% and 82%, respectively. Staged repair of TOF in young symptomatic infants results in 42% receiving PVSR, pulmonary artery growth, low incidence of postoperative arrhythmia, and relatively low rate of reoperations.

Pulmonary artery size is associated with functional clinical status in the Fontan circulation

ObjectiveIn the Fontan circulation, non-pulsatile pulmonary blood flow is suggested to negatively affect pulmonary artery growth. The pulmonary vasculature is regarded a key determinant of outcome after Fontan completion. We...

Surgical Management of Tetralogy of Fallot with Inadequate Size Pulmonary Artery Branches

Background: Tetralogy of Fallot (TOF) with inadequate size pulmonary artery (PA) branches continues to be a problem in many developing countries due to late presentation. Surgical management is still debatable in clinical practice. Our aim is to review our experience with different surgical modalities for management of this subset of patients. Methods: Between 2012 and 2018, out of 314 operations for TOF at our unit, there were 26 cases judged either pre-operatively or intraoperatively to have PA branches inadequate for total correction (McGoon’s ratio ≤ 1.5 or pulmonary branch size <-2 Z-value of expected size). Modified Blalock-Taussig shunt (MBTS) was done in 11 cases (shunt strategy). Open-heart surgery, involving going on cardiopulmonary bypass and cardiac arrest, was done in 15 cases (right ventricular outflow tract, RVOT, reconstruction strategy). The main PA was opened and the PA branches were sized from inside using Hegar sizers and Z-scores obtained. In 6 cases, the measured PA branches were smaller than the -2 Z-value, so, RVOT reconstruction without ventricular septal defect (VSD) closure (antegrade palliation) was done. The PA patch was adjusted to get a main PA annular diameter of not more than Z-value of -4, and to get an oxygen saturation on 25% FiO2 not exceeding 90%. In the remaining 9 cases, the sizes of the PA branches were found to accommodate a Hegar sizer within -2 Z-values. So, in those 9 patients, we proceeded to total repair with VSD closure. Results: There were no statistically significant differences between the 2 strategies (shunt vs. RVOT reconstruction) as regarding the preoperative parameters (age, weight, preoperative oxygen saturation on room air and the preoperative McGoon’s ratio of branch pulmonary arteries size). As regarding the postoperative data, there was statistically significant difference in the total mortality being less in RVOT reconstruction (1/15, 6.6%) compared to MBTS (4/11, 36.4%). The ratio between the diameters of branch pulmonary arteries was significantly lower in antegrade palliation than with MBTS, denoting more equal and even growth of pulmonary artery branches after antegrade palliation. Conclusion: In TOF patients judged preoperatively to have small PA branches not suitable for total correction, intra-operative direct assessment of the sizes of pulmonary artery branches by Hegar sizers is more accurate and reliable than preoperative imaging studies, and offered to save many patients from a two-stage repair allowing them a primary total repair with perfect results. In cases that needed a two-stage repair because of small PA branches, antegrade palliation yielded better early outcome than MBTS and furthermore provides uniform branch pulmonary arteries growth, which facilitates the 2nd stage total correction.

Anterograde blood flow associated with Blalock–Taussig shunts does not modify pulmonary artery growth compared with Blalock–Taussig shunt alone

The difference between extreme Tetralogy of Fallot (T4F) and pulmonary atresia with ventricle septal defect (PA/VSD) is the anterograde pulmonary blood flow. It is speculated that the association of modified Blalock-Taussig shunt (mBTs) and additional pulmonary blood flow favours shunt thrombosis but promotes better pulmonary arterial (PA) growth. This study sought to compare (PA) growth after mBTs shunt between T4F and AP/VSD. From 1995 to 2018, 79 mBTs were performed in infants (< 1 years), 45 for T4F and 34 for AP/VSD. Using a 1:1 propensity score match analysis, 38 patients were included ( n = 19 in each group). The primary outcome was, mBTs thrombosis, PA growth and operative mortality. After matching, the preoperative Nakata was similar (101 ± 8 mm 2 /m 2 in T4F; 106 ± 8 in AP/VSD P = 0.75). The age and weight were similar (24,3 ± 5 days, 3.3 ± 0.5 kg in T4F; 24,15 ± 4, 3.3 ± 0.9 in AP/VSD P = 0.84 and P = 0.77 respectively). The mBTs size was similar (4.15 ± 0.5 mm in T4F; 4.3 ± 0.5 in PA/VSD P = 0.35) There was no difference in in-hospital mortality ( n = 0, in T4F; n = 2,11% in AP/VSD, P = 0.14) and mBTs thrombosis (3,16% in T4F; 2,11% in AP/VSD, P = 0.18). The time to extubation tended to be longer in T4F (5 ± 1days vs. 2 ± 1 P = 0.06). The left and right PA diameter at time of biventricular repair were similar (7.5 ± 0.5 mm, 7 ± 0.2 in T4F; 8.1 ± 0.7 mm, 7 ± 1 in AP/VSD P = 0.43 and P = 0.78, Fig. 1 , Fig. 2 ) and the Nakata delta (112 ± 23 mm 2 /m 2 in T4F; 110 ± 17 in AP/VSD P = 0.78). Median time to complete repair was the same in the PA/VSD (12.26 [3.9–25] months) compared with T4F (9.7 [6.2–41.1] months) P = 0.87. The interstage reintervention were similar (3,16% in T4F; 4,22% in AP/VSD, P = 0.9). Anterograde blood flow with mBTs did not increase the risk of mBTs thrombosis. We couldn’t show benefit of anterograde blood flow with mBTS versus mBTS for pulmonary arteries growth. Anterograde blood flow did increase the time to extubation, probably by increasing total pulmonary blood flow.

Pulmonary artery growth after Modified Blalock-Taussig shunt: A single center experience

This study evaluates growth of pulmonary artery (PA) between different age groups after Modified Blalock-Taussig shunt (MBTS) based on a single center experience. We retrospective analyzed outcomes of 90 patients undergoing MBTS in our institute from January 1, 2010 to May 1, 2018. Patients were divided into three groups: Group 1, ≦2 months, Group 2, >2 months, ≦24 wmonths, Group 3, >24 months. The outcome included PA growth, overall survival rates and postoperative complications. 23 patients were involved in Group 1, while 49 in Group 2 and 18 in Group 3. The diameter of the PA, McGoon ratio, Nakata index and the oxygen saturation increased significantly after MBTS. Compared to pre-MBTS, there was no statistically significant increase of McGoon ratio in Group 3 after performing MBTS, but it witnessed less secondary cardiac surgery rate compared with Group 2 (11.11% vs. 48.98%, P=0.005). Cumulative survival rates of three groups were 60.53%, 85.70%, 94.40% at 1 year; 60.53%, 78.30%, 87.75% at 3 years and 60.53%, 78.30%, 87.75% at 5 years. Multivariable analysis showed diastolic blood pressure <30mmHg [OR 14.14 (1.92-104.32), P=0.009], cardiopulmonary bypass use [OR 16.79 (2.05-137.67), P=0.009] and single ventricle anomaly [OR 8.80 (1.18-65.54), P=0.034] were predictors of perioperative mortality. MBTS in our institute is a conventional and effective procedure for growth of PA especially for patients younger than 24 months. Patients with biventricular anomaly, no cardiopulmonary bypass use in surgery and relatively high postoperative diastolic blood pressure will likely offer a good prognosis.

Experience of a single institution with femoral vein homograft as right ventricle to pulmonary artery conduit in stage 1 Norwood operation

ObjectiveFemoral vein homograft can be used be used as valved right ventricle to pulmonary artery conduit in the Norwood operation. We describe the results of this approach, including pulmonary artery growth and ventricular function. MethodsA retrospective chart review of 24 consecutive neonates with hypoplastic left heart syndrome or complex single ventricle undergoing this approach between June 2012 and December 2017 was performed. Conduit valve competency and ventricular function were estimated using transthoracic echocardiogram, and pulmonary artery growth was measured using Nakata's index. Changes in ventricular function pre-Glenn and at latest follow-up were assessed by ordinal logistic regression with a general linear model to account for the correlation within the same patient over time. ResultsMedian age at surgery was 4 days, and mean weight was 3 kg. There was no interstage mortality. A total of 21 patients have undergone Glenn operation, and 9 patients have completed the Fontan operation. None of the conduits developed thrombosis. Sixty-three percent of conduits remained competent in the first month, and 33% remained competent after 3 months of operation. Catheter interventions on conduits were necessary in 14 patients. Median Nakata index at pre-Glenn catheterization was 228 mm2/m2 (interquartile range, 107-341 mm2/m2). Right ventricular function was preserved in 83% of patients at a median follow-up of 34 (interquartile range, 10-46) months. ConclusionsFemoral vein homograft as a right ventricle to pulmonary artery conduit in the Norwood operation is safe and associated with good pulmonary artery growth and preserved ventricular function as assessed by subjective echocardiography. Catheter intervention of the conduit may be necessary.