Pulmonary artery interventions after Norwood procedure: Does type or position of shunt predict need for intervention?

Surgical pulmonary arterioplasty at bidirectional cavopulmonary anastomosis leads to favorable pulmonary hemodynamics at final stage palliation

Objective

Pulmonary arterioplasty (PA plasty) at bidirectional cavopulmonary anastomosis (BDCA) is associated with increased morbidity, but outcomes to final stage palliation are unknown. We sought to determine the influence of PA plasty on pulmonary artery growth and hemodyamics at Fontan.

Methods

We retrospectively reviewed clinical data and outcomes for BDCA patients from 2006 to 2018. PA plasty was categorized by extent (type 1-4), as previously described. Outcomes included pulmonary artery reintervention and mortality before final palliation.

Results

Five hundred eighty-eight patients underwent BDCA. One hundred seventy-nine patients (30.0%) underwent concomitant PA plasty. Five hundred seventy (97%) patients (169 [94%] PA plasty) survived to BDCA discharge. One hundred forty out of 570 survivors (25%) required PA/Glenn reintervention before final stage palliation (59 out of 169 [35%]) PA plasty; 81 out of 401 (20%) non-PA plasty; P < .001). Twelve-, 24-, and 36-month freedom from reintervention after BDCA was 80% (95% CI, 74-86%), 75% (95% CI, 69-82%), and 64% (95% CI, 57-73%) for PA plasty, and 95% (95% CI, 93-97%), 91% (95% CI, 88-94%), and 81% (95% CI, 76-85%) for non-PA plasty (P < .001). Prefinal stage mortality was 37 (6.3%) (14 out of 169 PA plasty; 23 out of 401 non-PA plasty; P = .4). Five hundred four (144 PA plasty and 360 non-PA plasty) patients reached final stage palliation (471 Fontan, 26 1.5-ventricle, and 7 2-ventricular repair). Pre-Fontan PA pressure and pulmonary vascular resistance were 10 mm Hg (range, 9-12 mm Hg) and 1.6 mm Hg (range, 1.3-1.9 mm Hg) in PA plasty and 10 mm Hg (range, 8-12 mm Hg) and 1.5 mm Hg (range, 1.3-1.9 mm Hg) in non-PA plasty patients, respectively (P = .29, .6). Fontan hospital mortality, length of stay, and morbidity were similar.

Conclusions

PA plasty at BDCA does not confer additional mortality risk leading to final palliation. Despite increased pulmonary artery reintervention, there was reliable pulmonary artery growth and favorable pulmonary hemodynamics at final stage palliation.

Impact of preoperative left pulmonary artery stenting on the Fontan procedure: a retrospective multicentre study

OBJECTIVES

Left pulmonary artery (LPA) or bifurcation stenoses at Fontan palliation can be very challenging to treat and may also require cardioplegia and aortic transection. Moreover, the low pressure of Fontan circulation and the bulkiness of the aorta increase the risk of a patch angioplasty collapse. Pre-Fontan LPA stenting of stenotic LPAs overcomes those drawbacks therefore the present study aimed to evaluate its advantageous impact on Fontan surgery.

METHODS

A multicentre retrospective analysis was performed on 304 consecutive Fontan patients. The study population was divided into 2 groups (LPA stented, n = 62 vs not stented, n = 242); pre-and postoperative data were compared.

RESULTS

LPA-stented patients had a higher prevalence of systemic right ventricle (P = 0.01), hypoplastic left heart syndrome (P = 0.042), complex neonatal palliations (Norwood/Damus-Kaye-Stansel) and surgical LPA patch repair at Glenn (P < 0.001). No differences were found in cross-clamp rates, early (P = 0.29) and late survival (94.6% vs 98.4, P = 0.2) or complications (P = 0.14). Complex palliations on ascending aorta/aortic arch (P = 0.013) and surgical LPA repair at Glenn (P < 0.001) proved to be risk factors for LPA stenting before Fontan at multivariable analysis.

CONCLUSIONS

The LPA-stented group showed similar outcomes in terms of survival and complications rate compared to patients without LPA stenosis; however, they significantly differ in their higher preoperative risk profile and in their more complex anatomy. Complex neonatal palliations involving ascending aorta or aortic arch may increase the risk of pulmonary branches stenosis requiring stenting; therefore, preoperative stenting of LPA stenoses could help to reduce the surgical risk of complex Fontan procedure by avoiding the need for cross-clamp or complex mediastinal dissections to perform a high-risk surgical repair.

Decellularized vs Non-decellularized Allogeneic Pulmonary Artery Patches for Pulmonary Arterioplasty

We studied pulmonary artery size, reinterventions, and panel reactive antibodies in patients with single-ventricle physiology who underwent a pulmonary arterioplasty with decellularized (DAPAP) and non-decellularized allogeneic pulmonary artery patches (non-DAPAP). Retrospective review identified 59 patients with single-ventricle physiology who underwent pulmonary arterioplasty from 2008 to 2017: 28 patients underwent arterioplasty with DAPAP and 31 patients with non-DAPAP. Demographic and operative variables were similar between groups. Among patients who underwent a Norwood procedure, a right ventricle to pulmonary artery shunt was more commonly used in the DAPAP group (12/20, 60%) and a modified Blalock-Taussig shunt was more commonly used in the non-DAPAP group (17/22, 77%). On multivariable analysis, the use of DAPAP was associated with higher pre-Fontan angiography Z-scores in right (estimate = 0.17, standard error = 0.04, P = 0.0005) and left pulmonary arteries (estimate = 0.12, standard error = 0.05, P = 0.01). No areas of calcification, discrete coarctation, or pulmonary dilation were noted in any of the pulmonary arteries. On multivariable analysis, the use of DAPAP was associated with higher freedom from pulmonary artery reinterventions (Hazard ratio = 0.36, 95% confidence interval = 0.13-0.9, P = 0.04). The median value for Class I panel reactive antibodies was 0% (IQR 0, 4) in the DAPAP and 23% (IQR 14, 36) in the non-DAPAP group. The median value for Class II panel reactive antibodies was 15% (IQR 0, 17) in the DAPAP and 21% (IQR 10, 22) in the non-DAPAP group. Pulmonary arterioplasty with DAPAP was associated with higher pre-Fontan pulmonary artery Z-scores and higher freedom from pulmonary artery reinterventions.

Surgical reintervention on the neo-aorta after the Norwood operation

OBJECTIVES

We sought to identify the prevalence of surgical reintervention on the neo-aorta after Norwood procedure and its impact on long-term outcomes.

METHODS

We reviewed the medical records of all patients who underwent Norwood procedure. The impacts of surgical neoaortic reintervention on outcomes were analysed in each stage of palliation.

RESULTS

A total of 335 patients were included in this study. Thirty patients underwent surgical reintervention on the neo-aorta after Norwood procedure. The timing of initial reintervention was before stage II in 13 patients, at stage II in 7, between stage II and stage III in 5, at stage III in 3 and after stage III in 2. A reintervention before stage II was significantly associated with mortality (HR 14.4, 95% confidence interval 6.00-34.6, P < 0.001). In patients who underwent stage II (n = 251), reintervention had no significant impact on mortality. In patients who underwent stage III (n = 188), the previous reintervention was significantly associated with higher mean pulmonary pressure (P = 0.05) and a higher rate of reduced ventricular function (P = 0.002). Greater than mild atrioventricular valve regurgitation was significantly associated with the development of a neoaortic arch stenosis after stage II (P = 0.03).

CONCLUSIONS

Surgical reinterventions on the neo-aorta were required in each inter-stage phase. A surgical neoaortic reintervention was not related to increased mortality after stage II but significantly associated with a higher rate of reduced ventricular function and elevated mean pulmonary artery pressure.

[Early and long-term results after the Norwood procedure]

OBJECTIVE

To assess the early and long-term results after the Norwood procedure and to identify predictors of aortic recoarctation and arterial hypertension.

MATERIAL AND METHODS

We have operated on 2789 infants in the department of congenital heart diseases of the Meshalkin National Medical Research Center between January 2015 and December 2018. The current single-center prospective cohort study included 39 (1.4%) patients with hypoplastic left heart syndrome who underwent the Norwood procedure.

RESULTS

In-hospital mortality was 15.3% (n=6). An inter-stage mortality was 10.2% (n=4). Recoarctation of the aorta and Sano shunt stenosis in inter-stage period occurred in 8 (24.2%) and 4 patients (12.1%), respectively. Body mass <3 kg was the only risk factor of recoarctation (OR 7.08, 95% CI 1.17; 42.79, p=0.033). We found no risk factors of Sano shunt stenosis. There were no signs of recoarctation and Sano shunt dysfunction in the early postoperative period. Arterial hypertension developed in 14 (48.3%) patients. We found the correlation between systolic blood pressure and ventricular ejection fraction (β coefficient -0.88, 95% CI -1.33; -0.44, p=0.001). The only risk factor of arterial hypertension was increased stiffness of the aorta.

CONCLUSION

The early and inter-stage mortality are still the issues after the Norwood procedure. Postoperative reduced ejection fraction of single ventricle is one of the most common complications that could be related with residual arterial hypertension.

Recurrent Pulmonary Artery Interventions Following the Norwood Procedure Are Not Associated With Conduit Type

Given pulmonary artery interventions following the Norwood procedure can recur, the average number of occurrences per patient over time is likely more informative than the crude percentage of patients who required an intervention. Pulmonary artery intervention was defined as any surgical or catheter-based procedure after the Norwood procedure. The number of pulmonary artery interventions for patients with hypoplastic left heart syndrome were compared between patients with modified Blalock-Taussig Shunts (MBTS) and right ventricle-to-pulmonary artery conduits (RVPA) at a single institution from 2011 to 2018. The comparison was replicated using data from the Single Ventricle Reconstruction Trial (SVR), a nonoverlapping dataset. The mean number of pulmonary artery interventions per patient over time (mean cumulative function, MCF) is described using Nelson-Aalen estimates and compared using the pseudo-score test. The number of patients requiring intervention was compared using the chi-square test. Using our institutional dataset, the Norwood operation was performed on 117 patients (59 MBTS, 58 RVPA). In total, 73 patients had a pulmonary artery intervention, including 32 of 58 (55%) after MBTS and 41 of 59 (69%) after RVPA (P= 0.11). The MCF did not vary between cohorts (P = 0.55). Using the SVR trial dataset, 140 of 549 patients required pulmonary artery intervention, including 55 (21%) after MBTS and 85 (30%) after RVPA (P = 0.0090). The MCF did not vary between cohorts (P = 0.067). Although more patients with RVPA than MBTS require pulmonary artery interventions after the Norwood procedure, the MCFs are not different, which may be of greater importance to patients and families.

Geometry of the pulmonary arteries before the Fontan operation: can we influence it during the Norwood procedure?

OBJECTIVES

The right ventricle-to-pulmonary artery (RV-PA) shunt provides stable haemodynamics after the Norwood procedure but can influence development of the central pulmonary arteries (PAs). The goal of this study was to analyse the geometry of the central PAs in children with hypoplastic left heart syndrome before the Fontan operation with respect to the RV-PA shunt site and the type of the second-stage operation.

METHODS

A total of 161 children with hypoplastic left heart syndrome, median age 2.7 (range 1.3-9.8) years and median weight 12.7 (range 7.6-26.1) kg, underwent the Fontan operation after having had the Norwood procedure with an RV-PA shunt. The patients were divided into 2 groups: left-sided RV-PA (L-RV-PA) (n = 129) with the shunt on the left and right-sided RV-PA (n = 32) with the shunt on the right side of the neoaorta. Angiographic data obtained before the Fontan and all cardiac catheterization interventions were analysed retrospectively.

RESULTS

Between the second and third stages, as well as directly before the Fontan operation, the L-RV-PA group required more PA catheter interventions (P = 0.001 and P = 0.03). In this group, the minimal left PA diameter was smaller than that in the R-RV-PA group (P = 0.021). Leaving the shunt open until the Fontan operation increased the rate of PA interventions in the L-RV-PA group (P = 0.001), but there is no evidence of the impact on the development of the left PAs (P = 0.075). There is also no evidence that the type of the second-stage procedure influences the intervention rate before the Fontan procedure (P = 0.14).

CONCLUSIONS

Children who have the L-RV-PA shunt require more PA catheter interventions. The right-sided RV-PA shunt and the subsequent Glenn anastomosis in the place of the shunt are associated with distortion-free and more symmetrical development of the central PAs.

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

OBJECTIVE

Femoral 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.

METHODS

A 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.

RESULTS

Median 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.

CONCLUSIONS

Femoral 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.

Long term survival of hypoplastic left heart syndrome infants: Meta-analysis comparing outcomes from the modified Blalock-Taussig shunt and the right ventricle to pulmonary artery shunt

BACKGROUND

Stage 1 palliation of hypoplastic left heart syndrome (HLHS) involves the Norwood procedure combined with a modified Blalock-Taussig shunt (mBTS) or right ventricle to pulmonary artery shunt (RVPAS). Short-term survival has been described previously, whereas longer-term outcomes remain a subject of debate. This meta-analysis aimed to describe the short and long-term survival outcomes of these two shunts, and explore factors that might influence survival.

METHODS

Medline, Cochrane Libraries and EMBASE were systematically searched, and 32 studies were included for statistical synthesis, comprising 1348 mBTS and 1258 RVPAS patients.

RESULTS

While early in-hospital survival was superior in the RVPAS group (RR=1.5, p<0.05, 95% CI: 1.21-1.85), this difference was lost from 2years post-stage 1 palliation (RR=0.91, p>0.05, 95% CI: 0.79-1.04), and maintained unchanged up to 6years. This shift in survival was also reflected in inter-stage survival, with superior RVPAS outcomes between stage 1 and 2 (RR=1.62, p<0.05, 95% CI: 1.39-1.88), and equivalent outcomes between stage 2 and 3. Potential contributors to this included a significantly higher rate of pulmonary artery stenosis in the RVPAS group and an increased requirement for shunt re-intervention in this group prior to stage 2.

CONCLUSIONS

Despite early advantages, RVPAS and mBTS for palliation of hypoplastic left heart syndrome produced comparable long-term survival. The RVPAS patients experienced more pulmonary artery stenosis and requirement for shunt re-intervention. The impact of shunt type on quality and survival with a Fontan is yet to be assessed.

Femoral vein homograft as Sano shunt results in improved pulmonary artery growth after Norwood operation

OBJECTIVE

To evaluate differences in interstage growth of pulmonary arteries between use of polytetrafluoroethylene and femoral vein homograft as Sano shunt during stage-I Norwood palliation.

METHODS

A retrospective review of all patients who survived to the second stage following Norwood-Sano operation at two institutions was performed. Either polytetrafluoroethylene or the valved segment of femoral vein homograft was used for construction of the Sano shunt. The size of pulmonary arteries was compared at pre-Glenn catheterisation.

RESULTS

A total of 48 neonates with the diagnosis of hypoplastic left heart syndrome or its variants comprised the study population. Femoral vein homograft of 5-6 mm diameter was used in 14 and polytetrafluoroethylene graft of 5 mm was used in 34 patients. The two groups were comparable in terms of preoperative demographics and age at time of pre-Glenn catheterisation (3.9±0.7 versus 3.4±0.8 months, p=0.06). Patients who received femoral vein homograft demonstrated a significantly higher pre-Glenn Nakata index [264 (130-460) versus 165 (108-234) mm2/m2, p=0.004]. The individual branch pulmonary arteries were significantly larger in the femoral vein group (right, 7.8±3.6 versus 5.0±1.2, p=0.014; left, 7.2±2.1 versus 5.6±1.9, p=0.02). There were no differences in cardiac index, Qp:Qs, ventricular end-diastolic pressure or systemic oxygen saturations.

CONCLUSIONS

Utilisation of a valved segment of femoral vein homograft as right ventricle to pulmonary artery conduit during Norwood-Sano operation confers better interstage growth of the pulmonary arteries. Further studies are needed to evaluate the impact of femoral vein homograft on single ventricle function.

Femoral Vein Homograft as Right Ventricle to Pulmonary Artery Conduit in Stage 1 Norwood Operation

BACKGROUND

The polytetrafluoroethylene tube used as right ventricle to pulmonary artery conduit in the stage 1 Norwood operation is associated with risks of suboptimal branch pulmonary artery growth, thrombosis, free insufficiency, and long-term right ventricular dysfunction. Our experience with use of valved femoral vein homograft as right ventricle to pulmonary artery conduit is described.

METHODS

Between June 2012 and December 2015, 15 neonates with hypoplastic left heart syndrome or complex single ventricle underwent stage 1 Norwood operation with valved segment of femoral vein homograft as right ventricle to pulmonary artery conduit. The median age at surgery was 3 days and the mean weight was 3 kg. The size of the femoral vein homograft was 5 mm in 8 patients and 6 mm in 7 patients.

RESULTS

There was no hospital or interstage mortality. Fourteen patients underwent Glenn operation, and 6 have undergone Fontan operation to date. The median Nakata index at pre-Glenn catheterization was 262 mm²/m² (interquartile range: 121 to 422 mm²/m²). No patient had thrombosis of conduit. Most femoral vein conduits remained competent in the first month after stage 1 Norwood operation, although most became incompetent by 3 months. Catheter intervention on the conduit was necessary in 7 patients. Right ventricular function was preserved in most patients at follow-up.

CONCLUSIONS

The use of femoral vein homograft as right ventricle to pulmonary artery conduit in the Norwood operation is safe and associated with good pulmonary artery growth and preserved ventricular function. Balloon dilation of the conduit may be necessary during the interstage period.

Three-dimensional rotational angiography in the assessment of vascular and airway compression in children after a cavopulmonary anastomosis

The aim of the study was to examine the role of three-dimensional rotational angiography (3DRA) in assessing vascular and airway narrowing in children with a bidirectional cavopulmonary anastomosis (BCPA). The course of children with single ventricle physiology is often complicated by left pulmonary artery (LPA) and/or bronchial stenosis and may be related to aortic compression. 3DRA may be useful in evaluating this complex anatomy and possible mechanisms for the observed obstruction. Clinical data and imaging (2D angiography and 3DRA) of children with a BCPA were reviewed retrospectively. Measurements were taken at similar locations along the pulmonary arteries in both modalities and in the airways on 3DRA. Twenty-five children with a previous BCPA were assessed at mean age of 3.1 ± 2.0 years and weight of 13.6 ± 3.6 kg. Excellent correlation was found between 3DRA and 2D angiographic LPA measurements (r = 0.89, p < 0.0001). Twelve children had qualitative LPA stenosis on 3DRA, with a stenotic dimension of 6.6 ± 2.2 mm on 2D angiography and 6.8 ± 1.9 mm on 3DRA (r = 0.94, p < 0.0001). Ten cases with LPA stenosis also had bronchial stenosis (83 %). Qualitative airway assessment correlated with quantitative bronchial dimensions from 3DRA-derived tomographic images: Bronchial stenosis measured 4.4 ± 1.6 versus 5.9 ± 1.1 mm in those with a normal appearing bronchus (p = 0.009). Hybrid patients (initial palliation with bilateral pulmonary artery banding and arterial ductal stenting, n = 5) and all patients with a Damus-Kaye-Stansel (DKS) anastomosis (n = 9) were more likely to have LPA and left bronchial stenosis (OR 7.7, p = 0.04). 3DRA is a useful and accurate tool in assessment of LPA and airway narrowing after BCPA. Hybrid and DKS patients are more prone to LPA and bronchial stenosis, and 3DRA can provide insight into the mechanism.

Decision-Making for Surgery in the Management of Patients with Univentricular Heart

A series of technical refinements over the past 30 years, in combination with advances in perioperative management, have resulted in dramatic improvements in the survival of patients with univentricular heart. While the goal of single-ventricle palliation remains unchanged - normalization of the pressure and volume loads on the systemic ventricle, the strategies to achieve that goal have become more diverse. Optimal palliation relies on a thorough understanding of the changing physiology over the first years of life and the risks and consequences of each palliative strategy. This review describes how to optimize surgical decision-making in univentricular patients based on a current understanding of anatomy, physiology, and surgical palliation.

Pulmonary arterioplasty with decellularized allogeneic patches

BACKGROUND

Decellularized allogeneic nonvalved pulmonary artery patches for arterioplasty are a relatively new option compared with cryopreserved allogeneic, crosslinked xenogeneic bioprosthetic or synthetic materials. This study examines the midterm experience with a new decellularized allogeneic patch for congenital cardiac reconstructions.

METHODS

For this prospective postmarket approval, nonrandomized, inclusive observational study, we collected data on a consecutive cohort of 108 patients with cardiovascular reconstructions using 120 decellularized allogeneic pulmonary artery patches (MatrACELL; LifeNet Health, Inc, Virginia Beach, VA) between September 2009 and December 2012. One hundred of the patches were used for pulmonary arterioplasties. Two patients were lost early to follow-up and excluded from subsequent survival and durability analyses. Data included demographics, surgical outcomes, subsequent reoperations, and catheter reinterventions. These variables were also collected for an immediately preceding retrospective consecutive cohort of 100 patients with 101 pulmonary arterioplasty patches who received classical cryopreserved pulmonary artery allografts (n=59 patches and patients) or synthetic materials (n=41 patients with 42 patches) for pulmonary arterioplasties between 2006 and 2009.

RESULTS

In 106 patients with 118 decellularized patches, there were no device-related serious adverse events, no device failures, and no evidence of calcifications on chest roentgenograms. In contrast, the prior comparative pulmonary arterioplasty cohort of 100 patients experienced an overall 14.0% patch failure rate requiring device-related reoperations (p<0.0001) at mean duration of 194±104 days (range, 25 to 477 days).

CONCLUSIONS

The intermediate-term data obtained in this study suggest favorable performance by decellularized pulmonary artery patches, with no material failures or reoperations provoked by device failure.