Ventricle-pulmonary Artery Shunt Research Articles

Pulmonary Flow Management by Combination Therapy of Hemostatic Clipping and Balloon Angioplasty for Right Ventricular-Pulmonary Artery Shunt in Hypoplastic Left Heart Syndrome.

Controlling pulmonary blood flow in patients who have undergone Norwood palliation, especially early postoperatively, is challenging due to a change in the balance of systemic and pulmonary vascular resistance. We applied a combination therapy of clipping and balloon angioplasty for right ventricle-pulmonary artery (RV-PA) shunt to control pulmonary blood flow, but the influence of the combination therapy on the PA condition is uncertain. Retrospectively analysis was conducted of all infants with hypoplastic left heart syndrome who had undergone Norwood palliation with RV-PA shunt at Okayama University Hospital from January 2008 to September 2022. A total of 50 consecutive patients underwent Norwood palliation with RV-PA shunt in this study period. Of them, 29 patients underwent RV-PA shunt flow clipping, and the remaining 21 had unclipped RV-PA shunt. Twenty-three patients underwent balloon angioplasty for RV-PA shunt with clips. After balloon angioplasty, oxygen saturation significantly increased from 69 (59-76)% to 80 (72-86)% (p < 0.001), and the narrowest portion of the clipped conduit significantly improved from 2.8 (1.8-3.4) to 3.8 (2.9-4.6) mm (p < 0.001). In cardiac catheterizations prior to Bidirectional cavo-pulmonary shunt (BCPS), there were no significant differences in pulmonary-to-systemic flow ratio (Qp/Qs), ventricular end-diastolic pressure, Nakata index, arterial saturation, mean pulmonary artery pressure and pulmonary vascular resistance index. On the other hand, in Cardiac catheterizations prior to Fontan, Nakata index was larger in the clipped group (p = 0.02). There was no statistically significant difference in the 5-year survival between the two groups (clipped group 96%, unclipped group 74%, log-rank test: p = 0.13). At least, our combination therapy of clipping and balloon angioplasty for RV-PA shunt did not negatively impact PA growth. Although there is a trend toward better but not statistically significant difference in outcomes in the clipped group compared to the non-clipped group, this treatment strategy may play an important role in improving outcomes in hypoplastic left heart syndrome.

Right ventricle function longitudinal evaluation after norwood procedure: comparison between right ventricle-pulmonary artery shunt and blalock-taussing shunt

Abstract Background Norwood procedure represents the first of three surgical steps toward Hypoplastic left heart syndrome (HLHS) complete palliation. Two are the main surgical techniques allowing the reconstruction of Norwood circulation: the right ventricle-pulmonary artery shunt (RVPAS) and the modified Blalock-Taussing shunt (mBTS). However, still little is known about the impact on right ventricle (RV) function of the required ventriculotomy for the RVPAS. Purpose The aim of the study was to investigate the changes in RV function in HLHS patients after RVPAS vs mBTS. Methods The cohort included 27 consecutive HLHS patients (10 in the modified Blalock-Taussig shunt group and 17 in the RVPAS group) who successfully underwent Norwood procedure in a single tertiary paediatric cardiology centre. Longitudinal strain (LS) and strain rate (LSR), tricuspid annulus peak systolic excursion (TAPSE) and fractional area change (FAC) were evaluated in all patients before Norwood and in three different breakpoints in the steady state after Norwood procedure (30 days after Norwood, 90 days after Norwood, 140 days after Norwood). Results Ventricular loading conditions (diuretic treatment, blood pressure and tricuspid regurgitation) were similar in both groups. No significant differences were found at different time points between RVPAS and mBTS group in terms of LS, LSR, TAPSE and FAC. However, when we compared RV function before and after Norwood procedure, 90 days after the procedure, patients who did not undergo RV ventriculotomy (mBTS group) showed significant improvement in LS compared to pre-surgical assessment (mBTS: +27.35±43.47% vs RVPAS: −8,20±25.25%, p=0,03). This finding was consistent but no longer statistically significant at 140 days after Norwood (mBTS: +13.81±21.99% vs RVPAS: −4.90±27.97%, p=0,12). Conclusion After Norwood procedure mBTS patients showed a significant increase in LS when compared with patients who underwent RVPAS. This finding was consistent but no longer significant at 140 days after Norwood probably because the number of patients was too small to reach a significant level. These data support the use of LS in HLHS patient's evaluation and may be of value to find a patient-tailored timing for the second surgical stage. TAPSE, FAC, LS and LSR trends Funding Acknowledgement Type of funding source: None

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.

Mid-Term Outcome of Right Ventricle to Pulmonary Artery Shunt for Older Children and Young Adults With Ventricular Septal Defect, Pulmonary Atresia, and Hypoplastic Pulmonary Arteries

Management strategy for patients of ventricular septal defect and pulmonary atresia (VSD/PA) with hypoplastic pulmonary arteries presenting in late childhood or adolescence is still controversial. We present our experience with the use of right ventricle-pulmonary artery shunt (RV-PA) in management of this entity. Between January 2014 and April 2018, 25 patients of VSD/PA underwent valveless RV-PA shunt at our center. The size of the RV to PA shunt was calculated as half the expected diameter of the main pulmonary artery. We retrospectively reviewed the data from hospital records. Follow-up data were recorded from outpatient records or via telephone. Mean age of the cohort was 12.25 ± 3.18 years. There was 1 early and 1 interstage mortality. None of the patient developed acute renal failure, ventricular dysfunction, and arrhythmias. At interstage follow-up of 8.28 ± 3.7 months, both Nakata index (from 66.23 ± 24.12 to 185.8 ± 58 mm2/m2) and McGoon ratio (0.9 ± 0.22 vs 49 1.84 ± 0.4) increased significantly compared to preoperative value, whereas RPA-LPA ratio was not significantly changed (1.095 ± 0.39 vs 1.01 ± 0.56, P = 0.63). Prerepair pulmonary vascular resistance in 17 patients, who underwent complete repair, was 2.9 ± 0.69 woods unit/m2. Postrepair right ventricle-left ventricle pressure ratio was 0.5 ± 0.14. There was no early or late mortality and none of the patient required conduit revision or VSD fenestration. On follow-up of 25.75 ± 17.94 months, 16 patients were in NYHA I and 1 patient was in NYHA II. Appropriate-sized RV-PA shunt is an effective strategy for achieving balanced pulmonary artery growth in VSD/PA with hypoplastic pulmonary arteries presenting late without the risk of pulmonary over circulation or systemic malperfusion.

Extubation Failure Is Associated With Increased Mortality Following First Stage Single Ventricle Reconstruction Operation.

To identify the prevalence, causes, risk factors, and outcomes associated with extubation failure following first stage single ventricle reconstruction surgery. Retrospective cohort analysis of neonates who underwent a first stage single ventricle reconstruction operation. Extubation failure was defined as endotracheal reintubation within 48 hours of first extubation attempt. The Royal Children's Hospital, Melbourne. Data were collected for all infants who underwent a Norwood or Damus-Kaye-Stansel procedure between 2005 and 2014 at our institution. None. Extubation failure occurred in 23 of 137 neonates (16.8%; 95% CI, 11.0-24.1%) who underwent a trial of extubation. Overall, 42 patients (30.7%) were extubated to room air, 88 (64.2%) to nasal continuous positive airway pressure, and seven (5.1%) to high-flow nasal cannulae, though there was no major difference in extubation failure rates between these three groups (p = 0.37). The median time to reintubation was 16.7 hours (interquartile range, 3.2-35.2), and male infants failed extubation more frequently (63.2% vs 87.0%; p = 0.02), although age, gestation, weight, cardiac diagnosis (hypoplastic left heart syndrome vs other single ventricle conditions), shunt type (modified Blalock-Taussig vs right ventricle-pulmonary artery shunt), intraoperative perfusion times, preextubation mechanical ventilation duration, preextubation acid-base status, and postoperative fluid balance were not related to extubation outcome. Infants who failed extubation had a higher intensive care mortality (19.4% vs 3.5%; p = 0.03) and in-hospital mortality (30.4% vs 6.1%; p < 0.001). There is a high prevalence of extubation failure following first stage single ventricle reconstruction, and this is associated with considerably worse patient outcomes. The high prevalence and also the wide variation in rates of extubation failure in reported literature provide with an opportunity for implementation of quality assurance activities to minimize this complication and improve outcomes.

Comparison of right ventricle–pulmonary artery shunt position in the Single Ventricle Reconstruction trial

ObjectivePlacement of a right ventricle–pulmonary artery shunt to the left or right of the neoaorta may influence reinterventions, pulmonary artery development, and survival after the Norwood procedure because of differences in shunt and pulmonary artery geometry and blood flow. MethodsWe analyzed the Pediatric Heart Network Single Ventricle Reconstruction Trial public use dataset. Comparisons were made between patients who received a left- or right-sided right ventricle–pulmonary artery shunt during the Norwood procedure in both the overall (n = 274) and the propensity score–matched (67 pairs) patient cohorts. ResultsA left-sided shunt was placed in 168 patients (61%), and a right-sided shunt was placed in 106 patients (39%). At the 12-month follow-up, there were no differences in pulmonary artery measurements, hemodynamic measurements, or pulmonary artery reinterventions between shunt groups. However, the right-sided shunt was associated with fewer surgical shunt revisions in both the overall (8.3 vs 1.9 events per 100 infants, P = .05) and the propensity score–matched (17.9 vs 0 events per 100 infants, P < .001) patient cohorts. In the propensity score–matched cohort only, right-sided shunts were further associated with fewer serious adverse events (84 vs 46 events per 100 infants, P = .01) and improved transplantation-free survival at 3 years follow-up (61% [95% confidence interval, 48-72] vs 80% [95% confidence interval, 69-88], P = .04). ConclusionsIn the Single Ventricle Reconstruction trial, right ventricle–pulmonary artery shunt placement to the right of the neoaorta was associated with fewer shunt revisions and may contribute to improved outcomes in select patients.

Growing potential of small aortic valve with aortic coarctation or interrupted aortic arch after bilateral pulmonary artery banding.

Bilateral pulmonary artery banding (bPAB) is utilized for some patients with a ventricular septal defect (VSD) and aortic coarctation (CoA) or interrupted aortic arch (IAA). We evaluated aortic valve (AoV) diameter and patient outcomes following bPAB. Between August 2010 and September 2015, 10 consecutive patients with VSD and patent ductus arteriosus-dependent CoA or IAA underwent bPAB because of an AoV diameter of approximately <50% of the normal value (n = 6), severe subaortic stenosis and poor patient condition (n = 1, respectively), or low birthweight (n = 2). Second-stage operations were conventional total repair in five and Damus-Kaye-Stansel anastomosis, aortic arch reconstruction and right ventricle-pulmonary artery shunt (modified Norwood) type repair in five. After modified Norwood-type repair, four patients were Yasui-type repair candidates and one was a Fontan candidate. For all patients, the mean AoV diameter increased from 3.7 ± 0.7 mm before bPAB to 4.6 ± 0.8 mm before the second-stage operation. In five patients with CoA or IAA type A, the AoV diameter significantly increased from 3.5 ± 0.3 mm to 4.5 ± 0.5 mm during the term between bPAB and the second-stage operation, with an AoV Z-score increase from -5.82 ± 0.92 to -4.28 ± 0.86. IAA type B showed a slight increase in the AoV diameter. Initial palliation with bPAB enables AoV diameter growth in some patients, improving the likelihood of conventional total repair adaptation rate, particularly for CoA or IAA type A.

Maladaptive aortic properties after the Norwood procedure: An angiographic analysis of the Pediatric Heart Network Single Ventricle Reconstruction Trial

ObjectivesAortic arch reconstruction in children with single ventricle lesions may predispose to circulatory inefficiency and maladaptive physiology leading to increased myocardial workload. We sought to describe neoaortic anatomy and physiology, risk factors for abnormalities, and impact on right ventricular function in patients with single right ventricle lesions after arch reconstruction. MethodsPrestage II aortic angiograms from the Pediatric Heart Network Single Ventricle Reconstruction trial were analyzed to define arch geometry (Romanesque [normal], crenel [elongated], or gothic [angular]), indexed neoaortic dimensions, and distensibility. Comparisons were made with 50 single-ventricle controls without prior arch reconstruction. Factors associated with ascending neoaortic dilation, reduced distensibility, and decreased ventricular function on the 14-month echocardiogram were evaluated using univariate and multivariable logistic regression. ResultsInterpretable angiograms were available for 326 of 389 subjects (84%). Compared with controls, study subjects more often demonstrated abnormal arch geometry (67% vs 22%, P < .01) and had increased ascending neoaortic dilation (Z score 3.8 ± 2.2 vs 2.6 ± 2.0, P < .01) and reduced distensibility index (2.2 ± 1.9 vs 8.0 ± 3.8, P < .01). Adjusted odds of neoaortic dilation were increased in subjects with gothic arch geometry (odds ratio [OR], 3.2 vs crenel geometry, P < .01) and a right ventricle-pulmonary artery shunt (OR, 3.4 vs Blalock–Taussig shunt, P < .01) but were decreased in subjects with aortic atresia (OR, 0.7 vs stenosis, P < .01) and those with recoarctation (OR, 0.3 vs no recoarctation, P = .04). No demographic, anatomic, or surgical factors predicted reduced distensibility. Neither dilation nor distensibility predicted reduced right ventricular function. ConclusionsAfter Norwood surgery, the reconstructed neoaorta demonstrates abnormal anatomy and physiology. Further study is needed to evaluate the longer-term impact of these features.

Abstract 14733: Influence of High Risk Adrenergic Receptor Genotypes on Outcome in Infants With Single Ventricle

Introduction: Variants in adrenergic receptor (ADR) genes are associated with adverse clinical outcomes in patients with heart failure. We evaluated the association of variants in ADR receptor genes with outcomes in infants with single ventricle lesions. Methods: Infants with single ventricle lesions participating in the Pediatric Heart Network Single Ventricle Reconstruction Trial (randomized to Norwood with modified Blalock-Taussig shunt versus right ventricle-pulmonary artery shunt) underwent genotyping for 4 single nucleotide polymorphisms (SNPs) in 3 ADR genes: ADRB1-A/G (rs1801252), ADRB1-C/G (rs1801253), ADRB2-C/G (rs1042714) and ADRA2A-C/T (rs553668). Linear and logistic regression, deviance tests, t-tests and F-tests were used to analyze association of genotype with clinical outcomes including hospital length of stay (LOS) at Norwood, occurrence of serious adverse events (SAE), and transplant-free survival during 14 months follow-up using a dominant model. Results: The study included 347 eligible patients (62% male; 83% white). The mean age at Norwood procedure was 6±3.6 days and median Norwood LOS was 8 days. During 14 months follow-up, 147 patients had SAEs, 94 patients died and 14 were transplanted. ADRB1 AA (rs1801252) genotype was associated with longer Norwood LOS. The difference in LOS between AA vs AG/GG was 7.99 days (confidence intervals, 0.27, 15.71; p=0.043). ADRA2A CC (rs553668) genotype was associated with higher odds of SAEs i.e. 103/216 (47.6%) in CC compared to 36/106 (34%) in CT/TT [Odds ratio 1.77 (confidence intervals, 1.09, 2.87), p=0.018]. Transplant-free survival was not different between genotype groups. Combined analysis of risk genotypes did not confer an additive risk of adverse outcomes. Conclusions: ADR genotypes known to cause adrenergic upregulation were associated with prolonged Norwood hospitalization and/or serious adverse events in infant single ventricles. This may be secondary to adverse effects of adrenergic overexpression on cardiac function and systemic hemodynamics. Analysis is ongoing to replicate these findings for utility as predictive markers for outcomes in infant single ventricles.

A left anterior extrapleural approach to adjust right ventricle-pulmonary artery shunt flow using hemostatic clips after the Norwood operation.

Adjusting right ventricle-pulmonary artery shunt flow with placement of hemostatic clips in the Norwood operation is a useful technique for precise control of pulmonary blood flow in the acute postoperative period. This report describes our technique for optimizing right ventricle-pulmonary artery shunt flow with metal clips through a left anterior extrapleural approach, which can be performed safely and minimally invasively without sternal reopening. This procedure may decrease morbidity and contribute to long-term clinical improvement in patients undergoing the Norwood operation.

Association of Hematocrit and Red Blood Cell Transfusion with Outcomes in Infants Undergoing Norwood Operation.

The objective of this study was to investigate the association between red blood cell (RBC) transfusion and hematocrit values with outcomes in infants undergoing Norwood operation. This study included infants ≤2 months of age who underwent Norwood operation with either a modified Blalock-Taussig shunt or a right ventricle-pulmonary artery shunt. Demographics, preoperative, operative, daily laboratory data, and postoperative variables were collected. The primary outcome measures evaluated included mortality, ICU length of stay, length of mechanical ventilation, and days to chest closure. The secondary outcome measures evaluated included lactate levels, estimated glomerular filtration rate, and inotrope score in the first 14 days after heart operation. Cox proportional hazard models were fitted to study the probability of study outcomes as a function of hematocrit values and RBC transfusions after operation. Eighty-nine patients qualified for inclusion. With a median hematocrit of 46 (IQR 44, 49), and a median RBC transfusion of 92 ml/kg (IQR 31, 384) in the first 14 days after operation, 81 (91 %) patients received RBC transfusions. A multivariable analysis adjusted for risk factors, including the age, weight, prematurity, cardiopulmonary bypass and cross-clamp time, and postoperative need for nitric oxide and dialysis, demonstrated no association between hematocrit and RBC transfusion with majority of study outcomes. This single-center study found that higher hematocrit values and increasing RBC transfusions are not associated with improved outcomes in infants undergoing Norwood operation.

左心低形成症候群に対する外科治療：3ヶ月Norwood＋両方向性Glenn手術と1ヶ月Norwood＋右室–肺動脈シャント手術の比較

左心低形成症候群に対する外科治療：3ヶ月Norwood＋両方向性Glenn手術と1ヶ月Norwood＋右室–肺動脈シャント手術の比較

Intervention for Recoarctation in the Single Ventricle Reconstruction Trial

Background— Recoarctation after the Norwood procedure increases risk for mortality. The Single Ventricle Reconstruction (SVR) trial randomized subjects with a single right ventricle undergoing a Norwood procedure to a modified Blalock-Taussig shunt or a right ventricle–pulmonary artery shunt. We sought to determine the incidence of recoarctation, risk factors, and outcomes in the SVR trial. Methods and Results— Recoarctation was defined by intervention, either catheter based or surgical. Univariate analysis and multivariable Cox proportional hazard models were performed with adjustment for center. Of the 549 SVR subjects, 97 (18%) underwent 131 interventions (92 balloon aortoplasty, 39 surgical) for recoarctation at a median age of 4.9 months (range, 1.1–10.5 months). Intervention typically occurred at pre–stage II catheterization (n=71, 54%) or at stage II surgery (n=38, 29%). In multivariable analysis, recoarctation was associated with the shunt type in place at the end of the Norwood procedure (hazard ratio, 2.0 for right ventricle–pulmonary artery shunt versus modified Blalock-Taussig shunt; P =0.02), and Norwood discharge peak echo-Doppler arch gradient (hazard ratio, 1.07 per 1 mm Hg; P &lt;0.01). Subjects with recoarctation demonstrated comorbidities at pre–stage II evaluation, including higher pulmonary arterial pressures (15.4±3.0 versus 14.5±3.5 mm Hg; P =0.05), higher pulmonary vascular resistance (2.6±1.6 versus 2.0±1.0 Wood units·m 2 ; P =0.04), and increased echocardiographic volumes (end-diastolic volume, 126±39 versus 112±33 mL/BSA 1.3 , where BSA is body surface area; P =0.02). There was no difference in 12-month postrandomization transplantation-free survival between those with and without recoarctation ( P =0.14). Conclusions— Recoarctation is common after Norwood and contributes to pre–stage II comorbidities. Although with intervention there is no associated increase in 1-year transplantation/mortality, further evaluation is warranted to evaluate the effects of associated morbidities. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00115934.

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Abstract 9363: Intervention for Re-coarctation in the Single Ventricle Reconstruction Trial: Incidence, Risk and Outcomes

Objectives: To determine the incidence of re-coarctation (re-CoA), risk factors and outcomes in patients with single right ventricle lesions after Norwood. Methods: The cohort included subjects randomized to right ventricle-pulmonary artery shunt (RVPAS) or modified Blalock Taussig shunt (MBTS) in the Single Ventricle Reconstruction (SVR) Trial. Re-CoA was defined by intervention, either catheter-based or surgical. Univariate analysis and multivariable Cox proportional hazard models were performed adjusting for center. Results: Of the 549 SVR subjects, 97 (18%) underwent 137 interventions (92 balloon aortoplasty; 45 surgical) for re-CoA. Intervention typically occurred at pre-stage II catheterization (n=71, 52%) or at stage II surgery (n=44, 32%). Median age and catheterization gradient at first intervention were 4.9 months (range: 1.1-10.5) and 17 mm Hg (range: 0-60) respectively. Center intervention rates varied from 0-50%. In multivariable analysis, re-CoA was not associated with assigned shunt type, but was associated with actual shunt type received (HR 2.0 for RVPAS vs. MBTS, p=0.02), and Norwood discharge peak echo-Doppler arch gradient (HR 1.07 per 1 mm Hg, p&lt;0.01). No other demographic, anatomic or surgical variables predicted intervention. Subjects with re-CoA demonstrated comorbidities at pre-stage II evaluation including higher pulmonary arterial pressures (15.4 ± 3.0 vs. 14.5 ± 3.5 mm Hg; p=0.05), higher pulmonary vascular resistance (2.6 ± 1.6 vs. 2.0 ± 1.0 WU x m²; p=0.04) and increased echocardiographic volumes (end-diastolic volume: 28.0 ± 7.4 vs. 24.9 ± 8.2 ml; p=0.01). There was no difference in 12-month post-randomization transplant-free survival for those with and without re-CoA (83% vs. 86%; p=0.5). Conclusions: Intervention for re-CoA was common and varied by center. The association with receipt of an RVPAS may be due to intra-operative cross-over because of arch anatomy that prohibited use of a MBTS. Those undergoing intervention demonstrated ventricular dilation and worsened hemodynamics prior to stage II surgery. Although intervention was not associated with increased 1-year transplant/mortality, further evaluation is warranted to evaluate effects of morbidity of re-CoA.

Intact Right Ventricle–Pulmonary Artery Shunt After Stage 2 Palliation in Hypoplastic Left Heart Syndrome Improves Pulmonary Artery Growth

For patients with hypoplastic left heart syndrome who have undergone the Norwood procedure with a right ventricle-pulmonary artery (RV-PA) shunt, the shunt can either be removed or left intact at the time of the stage 2 procedure. This study aimed to determine the effects of an intact shunt on pulmonary artery growth and clinical outcomes after the stage 2 procedure. A retrospective review of patients who underwent Norwood with an RV-PA shunt from 2005 to 2010 was performed. Catheterization data, echocardiographic data, postoperative outcome variables, and mortality data were collected. Pulmonary artery size was measured at pre-stage 2 and pre-Fontan catheterizations using the Nakata Index and the McGoon Ratio. Of the 68 patients included in the study, 48 had the shunt removed at the time of stage 2 (group 1), and 20 had the shunt left intact (group 2). The two groups did not differ in terms of pre-stage 2 hemodynamics or pulmonary artery size. After stage 2, group 2 had higher oxygen saturations. The two groups did not differ regarding duration of chest tube drainage, length of hospital stay, need for unplanned interventions, or mortality. Before Fontan, the group 2 patients had higher superior vena cava (SVC) pressures and more venovenous collaterals closed. There was increased pulmonary artery growth between the pre-stage 2 and pre-Fontan catheterizations in group 2 using both the Nakata Index (+148.5 vs -52.4 mm(2)/m(2); p = 0.01) and the McGoon Ratio (+0.36 vs +0.01; p = 0.01). These findings indicate that patients with an intact RV-PA shunt after stage 2 have greater pulmonary artery growth than patients with the shunt removed, with no increased risk of complications.

Usefulness of balloon angioplasty for the right ventricle‐pulmonary artery shunt with the modified norwood procedure

We sought to evaluate the efficacy of balloon angioplasty (BA) for severely desaturated patients due to a stenotic right ventricle (RV) to pulmonary artery (PA) shunt following modified Norwood procedure. Of 87 patients who underwent a Norwood procedure with the RV-PA shunt between February 1998 through March 2010, 22 (25%) patients underwent BA. The efficacy of BA was assessed by angiographic measurement of the changes in the internal diameters of the stenotic portions of the shunt, changes in arterial saturation and clinical outcomes. BA was performed for stenotic RV-PA shunts following stage I palliation (n = 17, 77%), or those placed as an additional blood source (n = 5, 23%, 3 patients awaiting biventricular repair, 2 patients following stage II palliation). The location of the BA was at the distal anastomosis in 12 (54.5%), proximal anastomosis in 21 (95.4%) and in the mid-portion of the shunt in 11 (50%) cases. The diameters of these three shunt portions were measured from the anterior-posterior and lateral angiographic images, increasing significantly after BA (p < 0.0001) in all. Arterial saturation significantly improved after BA in all cases (66.5 ± 4.3% to 79.4 ± 3.4%, p < 0.0001). Freedom from reintervention was 100%. All patients underwent subsequent elective planned surgery at an appropriate age with no mortality. A BA-alone strategy for a stenotic RV-PA shunt was effective for all three shunt portions, minimizing shunt-related premature surgical intervention.

Does Initial Shunt Type for the Norwood Procedure Affect Echocardiographic Measures of Cardiac Size and Function During Infancy?

Background— The Pediatric Heart Network trial comparing outcomes in 549 infants with single right ventricle undergoing a Norwood procedure randomized to modified Blalock-Taussig shunt or right ventricle–pulmonary artery shunt (RVPAS) found better 1-year transplant-free survival in those who received RVPAS. We sought to compare the impact of shunt type on echocardiographic indices of cardiac size and function up to 14 months of age. Methods and Results— A core laboratory measured indices of cardiac size and function from protocol exams: early after Norwood procedure (age 22.5±13.4 days), before stage II procedure (age 4.8±1.8 months), and at 14 months (age 14.3±1.2 months). Mean right ventricular ejection fraction was &lt;50% at all intervals for both groups and was higher in the RVPAS group after Norwood procedure (49±7% versus 44±8%; P &lt;0.001) but was similar by 14 months. Tricuspid and neoaortic regurgitation, diastolic function, and pulmonary artery and arch dimensions were similar in the 2 groups at all intervals. Neoaortic annulus area (4.2±1.2 versus 4.9±1.2 cm 2 /m 2 ), systolic ejection times (214.0±29.4 versus 231.3±28.6 ms), neoaortic flow (6.2±2.4 versus 9.4±3.4 L/min per square meter), and peak arch velocity (1.9±0.7 versus 2.2±0.7 m/s) were lower at both interstage examinations in the RVPAS compared with the modified Blalock-Taussig shunt group ( P &lt;0.001 for all), but all were similar at 14 months. Conclusions— Indices of cardiac size and function after the Norwood procedure are similar for modified Blalock-Taussig shunt and RVPAS by 14 months of age. Interstage differences between shunt types can likely be explained by the physiology created when the shunts are in place rather than by intrinsic differences in cardiac function. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00115934.

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Successful Fontan Completion After Cardiac Resynchronization Therapy

This patient underwent a modified Norwood operation with a right ventricle–pulmonary artery shunt at the age of 7 days following the diagnosis of hypoplastic left heart syndrome with mitral and aortic atresia; this procedure was followed by bidirectional Glenn operation at the age of 5 months. The girl subsequently developed congestive heart failure despite the administration of angiotensin-converting enzyme inhibitors and β-blockers after the initial operation. At the age of 11 months, she required hospitalization and intravenous inotropic support. Coil embolization and surgical ligation of the aortopulmonary collaterals were performed at the age of 1 year but could not control the heart failure. The maximum plasma brain natriuretic peptide level after the second palliative operation was 3823 pg/mL. Cardiac catheterization performed at the age of 1 year and 4 months revealed ventricular dyssynchrony, ventricular ejection fraction of 36.2%, right atrial pressure of 7 mm Hg, superior vena cava pressure of 16 mm Hg, and grade 2 tricuspid regurgitation. QRS duration was 184 ms (Figure 1), and arterial oxygen saturation was 80%. To detect the most delayed and earliest …