Hypoplastic Pulmonary Arteries Research Articles

Palliative Right Ventricular Outflow Tract Stenting in Tetralogy of Fallot with Severe Cyanosis: Experience from a Single Center in Southern India

Background: This study conducted at an Indian tertiary care hospital aimed to characterize the clinical profile of tetralogy of Fallot (ToF) patients undergoing right ventricular outflow tract (RVOT) stenting and assess their immediate postprocedural outcomes until discharge. Methods: In this retrospective analysis, the clinical and procedural outcomes were analyzed for 20 patients who underwent palliative stenting in the RVOT for severe cyanosis associated with ToF during 2021–2023. Results: The median age for the patients was 2.3 years (range 3 months–21 years), two being adults (>18 years). Fourteen (70%) patients underwent elective RVOT stent and 30% underwent emergency stenting. The most common indication of RVOT stenting was hypoplastic branch pulmonary arteries (PAs) (n = 11, 78.6%) and cyanotic spell (n = 4, 66.7%) for elective and emergency surgeries, respectively. The average improvement in SpO2 was 27.2% (95% confidence interval 23.4–31.0, P < 0.001). Six (30%) patients had complications including reperfusion injury of lungs (n = 2, 33.4%) sepsis (n = 1, 16.7%), stent embolization (n = 1, 16.7%), re-stenting (n = 1, 16.7%), transient complete heart block (n = 1, 16.7%) during the procedure, and. One child went through RVOT stent postoperative due to severe residual stenosis and child developed severe tricuspid regurgitation and succumbed to death due to culture positive sepsis with multi-organ dysfunction. Rest (n = 19, 95%) were discharged with an average 6.7 days of hospital stay. Conclusion: ROVT stenting is a safe and effective palliative management in ToF enhancing oxygen saturation prior to definitive surgical repair.

Technical Details of a Novel Surgical Procedure for Construction of the Modified Blalock–Taussig Shunt (UKC’s Modification): A Video Presentation

We describe herein the surgical technique on a 2.5-years-old male child weighing 10 kilograms diagnosed with a functionally univentricular heart, disproportionately small right subclavian artery, and hypoplastic pulmonary arteries (Mc Goon’s ratio of less than 1.0).5 We interposed a short segment of polytetrafluroethylene graft between the right brachiocephalic artery and the intrapericardial portion of the right pulmonary artery closest to the bifurcation of the pulmonary trunk on the right side.

Short-term outcomes following total correction of tetralogy of fallot in adult patients

ObjectivesTetralogy of Fallot (TOF) is a common congenital heart disease which should be corrected. The recommended time for the Tetralogy of Fallot Total Correction (TFTC) surgery is during the infancy for the possible difficulties during the surgery and the related issues. However, sometimes TOF is diagnosed and managed during the adulthood.MethodsThis study is a descriptive and retrospective one which included all patients who underwent TFTC at the age of 15-year and older in 10 years (between the years 2010 and 2020) to identify short-term (in-hospital mortality, ICU stay, postoperative bleeding, respiratory complications after the surgery such as pulmonary edema, pneumonia, etc.) and one-year (left ventricle ejection fraction (LVEF), right ventricle (RV) ejection fraction, the severity of tricuspid and aortic regurgitation after surgery) outcomes. All data were taken from medical records at Rajaie Cardiovascular Medical and Research Center. Data were analyzed using SPSS 22.Results94 patients with the mean ± SD age of 26.7 ± 9.6 years were enrolled. Most of them were male (59.6%) (P-value: 0.009). In-hospital mortality in our study were 5.3%. Tricuspid regurgitation (TR) was significantly resolved after the surgery (P-value: 0.006). Of 17 (18.1%) patients with small or hypoplastic pulmonary artery (PA) branches, 14 patients had acceptable PA branch size after surgery.ConclusionTFTC at an older age is safe with acceptable results. Age is not a contraindication for TFTC and surgery should be recommended if the patients are diagnosed with TOF in adulthood. Also, the TOF diagnosis should be considered in adult patients with suspicious signs and symptoms.

Patterns of Aortic Dilation in Tetralogy of Fallot: An Analysis of 100 Fetal Echocardiograms Compared With Matched Controls.

Background Although aortic dilation is common in tetralogy of Fallot (TOF), its progression and risk of dissection are not well understood. The mechanism of dilation is primarily attributed to increased flow in utero; an alternative is unequal septation of the truncus arteriosus resulting in a larger aorta and inherently hypoplastic pulmonary artery (PA). If the latter is true, we hypothesize the aorta to PA ratio in TOF is stable throughout gestation, and sums of great artery dimensions are similar to controls. Methods and Results We performed a single-center retrospective study of fetuses with TOF (2014-2020) and matched controls. We compared sums of diameters, circumferences, and cross-sectional areas of the aorta and PA and evaluated the aorta to PA ratio across gestation in 2 TOF subtypes: pulmonary stenosis and atresia (TOF-PA). There were 100 echocardiograms with TOF (36% TOF-PA) with median gestational age of 31 weeks (interquartile range 26.5-34.4) and median maternal age of 34 years (interquartile range 30-37). There were no differences in sums of great artery dimensions between TOF-pulmonary stenosis and controls. In TOF-PA, sums were significantly lower than controls (P values <0.01). The aorta to PA ratio was stable throughout gestation (Pearson's r=0.08 [95% CI, -0.12 to 0.27], -0.06 [95% CI, -0.25 to 0.14]). Conclusions The aorta in fetal TOF is large but grows proportionally throughout gestation, with sums of great artery dimensions similar to controls. TOF-PA appears distinct from TOF-pulmonary stenosis (with smaller sums), warranting further investigation. In conclusion, our findings suggest an intrinsic developmental mechanism contributes to aortic dilation in TOF.

T-Remodeling of the Pulmonary Artery Bifurcation for Pulmonary Artery Origin Stenosis.

Various surgical techniques are utilized for reconstructing hypoplastic pulmonary arteries (PAs) in patients with conotruncal anomalies and at times, may be susceptible to restenosis and reoperation. We reviewed our experience with a simple technique of T-shaped remodeling of the PA bifurcation. Between 2005 and 2019, 31 patients underwent T-remodeling of central PAs by a single cardiac surgeon. The PA bifurcation was opened cranially, and the opening was augmented with an oval-shaped patch effectively transforming the V-shaped bifurcation into a T-shaped bifurcation. Both origins of the PAs were enlarged, even in the instance of single PA origin stenosis. Median age at time of T-remodeling was 17 months (range: 7 weeks to 14 years). The following cardiac morphologies were observed: tetralogy of Fallot (n = 12, 39%), pulmonary atresia with ventricular septal defect (VSD) and major aortopulmonary collateral arteries (n = 8, 26%), truncus arteriosus (n = 6, 19%), pulmonary atresia with VSD (n = 3, 9.7%), and transposition of the great arteries (n = 2, 6.5%). Thirteen patients (42%) had previous central shunt, and eight patients (26%) had previous modified Blalock-Taussig shunt. There were no operative mortalities. Immediately after T-remodeling, echocardiographic estimates of right ventricle to PA gradient decreased from 42 [interquartile range 28-58] mm Hg to 20 [12-36] mm Hg (P = .03). Freedom from reoperation on the PA bifurcation for the entire cohort was 100% at one year, 88% (95% CI 68%-96%) at five years and 82% (57%-93%) at ten years. T-remodeling for PA origin stenosis is a safe procedure with excellent freedom from reoperation that is easily reproducible and applicable to patients with all cardiac morphologies.

Impact of Optimal Fenestration Size on Outcomes of High-Risk Fontan Patients.

We aimed to analyze mid-term outcomes of the fenestrated Fontan procedure, focusing on the fenestration size. We retrospectively reviewed the outcomes of the fenestrated Fontan procedure. Among 165 patients who underwent the Fontan procedure from 2011 to 2021, fenestration was created in 27 patients with the highest risks, including those with hypoplastic left heart syndrome, hypoplastic pulmonary arteries, heterotaxy syndrome with high pulmonary vascular resistance, and pulmonary arterial pressure >15 mm Hg. The patients underwent the procedure at a median age of three years (body weight, 11.4 kg; body surface area, 0.54 m2). Fenestration sizes were 3.5 to 5 mm. Spontaneous fenestration closure occurred within one year postoperatively in nine patients. Among them, three experienced Fontan failure, necessitating refenestration. Although fenestration size did not differ, the size corrected by body surface area at the time of surgery was smaller in patients with fenestration closure (6.4 mm/m2 vs 8.3 mm/m2, P < .05). Patients with a fenestration <7 mm/m2 were more likely to have fenestration closure within one year postoperatively, and those with a fenestration >9 mm/m2 were more likely to have severe desaturation and require home oxygen therapy following discharge. Spontaneous fenestration closure affected the frequency of Fontan complications. A very small fenestration size corrected by body surface area was a significant risk factor for spontaneous closure. Conversely, a very large fenestration size corrected by body surface area resulted in severe desaturation. The optimal fenestration size to prevent early spontaneous closure and severe desaturation is approximately 8 mm/m2.

Pulmonary Artery Hypoplasia in Neonates With Tetralogy of Fallot

BackgroundNeonates with symptomatic tetralogy of Fallot (sTOF) with hypoplastic pulmonary arteries (hPA) are considered high risk. Data are needed to inform the impact of hPA on outcomes, and the ideal management strategy. ObjectivesThe objectives of this study were to quantify the impact of hPA on outcomes in neonates with sTOF and measure the impact of strategy on pulmonary artery (PA) growth in this population. MethodsNeonates with sTOF from 2005 to 2017 were reviewed from the Congenital Cardiac Research Collaborative. Criteria for hPA included a unilateral PA z score <−2.0 and contralateral PA z score <0. Primary outcome was mortality. Secondary outcomes included reintervention and PA growth. ResultsWe included 542 neonates with sTOF, including 188 (35%) with hPA and 354 (65%) with normal PA, with median follow-up of 4.1 years. Median right and left hPA z scores were −2.19 (25th-75th percentile: −2.55 to −1.94) and −2.23 (25th-75th percentile: −2.64 to −1.91), respectively. Staged repair (vs primary TOF repair) was less common in the hPA cohort (36 vs 44%; P = 0.07). Survival was similar between groups (unadjusted P = 0.16; adjusted P = 0.25). Reintervention was more common in the hPA group (HR: 1.28; 95% CI: 1.01-1.63; P = 0.044); there was no difference after definitive repair (HR: 1.21; 95% CI: 0.93-1.58; P = 0.16). PA growth at 1 year was greater in the hPA cohort, particularly for the right PA (P < 0.001). ConclusionsDespite perception, the presence of hPA in neonates with sTOF conferred no increase in overall hazard of mortality or reintervention after definitive repair. PA growth was superior in the hPA cohort. These findings suggest that the presence of hPA does not adversely impact outcomes in sTOF.

Impact of Antegrade Pulmonary Blood Flow as Patients Progress Through Single-Ventricle Palliations

BackgroundThe impact of antegrade pulmonary blood flow (APBF) during single-ventricle (SV) palliation continues to be debated. We sought to assess its impact on the hemodynamic profile and the short- and long-term outcomes of patients progressing through stages of SV palliation. MethodsA retrospective single-center study was conducted of SV patients who underwent surgery between January 2010 and December 2020. Patients with APBF were matched to those with no APBF by a propensity score based on body surface area, sex, and type of systemic ventricle. Analysis was performed using appropriate statistics with a significance level of P = .05. ResultsSixty-three patients with APBF were matched with 95 patients with no APBF. At the pre–stage 2 catheterization, APBF patients had a larger left pulmonary artery diameter (z score, 0.1 vs −0.8; P < .042). Patients with APBF had shorter cardiopulmonary bypass time (57.0 vs 79.0 minutes), shorter duration of mechanical ventilation (14.1 vs 17.4 hours), and shorter hospital length of stay (5.0 vs 7.0 days) at stage 2 palliation (P < .05). In the multivariable Cox regression analysis, patients with hypoplastic pulmonary arteries (z scores < −2; adjusted hazard ratio, 9.17) and patients with chromosomal abnormalities/genetic syndrome (adjusted hazard ratio, 4.03) were at increased risk for poor outcomes (P < .05). During the follow-up period, there was no significant difference in risk of the composite poor outcome and long-term survival between groups. ConclusionsSV patients with APBF had shorter cardiopulmonary bypass time, duration of mechanical ventilation, and hospital length of stay after stage 2 palliation. Patients with hypoplastic pulmonary arteries or chromosomal abnormalities/genetic syndromes had increased risk for poor outcomes. Maintaining APBF has better short-term outcomes, but there are no long-term hemodynamic or survival benefits.

Long-term outcomes of patients with single ventricle who do not undergo Fontan palliation

BackgroundPatients with single ventricle (SV) without Fontan palliation are uncommon, and their long-term outcomes remain unclear. MethodsRetrospective study of 35 adult patients with SV without Fontan from two tertiary centers. Primary outcome was mortality. ResultsMedian age at first follow-up was 31 years (IQR: 20–40). Most common defect was double inlet left ventricle (34%), and 69% had left ventricular morphology. Patients were unoperated (46%), had systemic-to-pulmonary artery shunt (31%) or bidirectional cavopulmonary shunt (23%) as final palliation. Most common reasons for not progressing to Fontan palliation were pulmonary vascular disease (54%), patient refusal (17%), Fontan takedown (14%), and hypoplastic pulmonary arteries (11%). Baseline mean hemoglobin was 195 ± 29 g/L, mean O2 saturation 83 ± 6.9%, and 4 patients in NYHA Class III‒IV. After a mean follow-up of 10 ± 8.3 years, there were 9 deaths with heart failure being the leading cause (n = 6). Age-adjusted survival of these adult SV survivors was 73% and 53% at 40 and 50 years of age, respectively. Deceased patients more frequently had renal impairment (50% vs 0%) and QRS prolongation (75% vs 16%) at baseline (all p < 0.05). During follow-up, 40% had a new arrhythmia (atrial: n = 14, ventricular: n = 3), 34% had one or more hospitalizations for heart failure, and 17% had a stroke. A greater proportion of patients with pre-existing or new atrial/ventricular arrhythmia died compared to those without (42% vs 6%, p = 0.02). ConclusionsPatients with SV without Fontan have high mortality and a substantial burden of cardiovascular complications, particularly arrhythmia. QRS prolongation and renal impairment were associated with mortality.

Revisiting the central aortopulmonary shunt procedure.

In this study, we present our experience with the central aortopulmonary shunt technique with interposing a polytetrafluoroethylene graft between main pulmonary artery (end-to-end) and the ascending aorta (side-to-side) in a variety of cyanotic congenital heart defects. Between January 2019 and June 2022, a total of 10 patients (6 males, 4 females; mean age: 4.3±2.8 months; range, 5 days to 10 months) with hypoplastic central pulmonary arteries who underwent central aortopulmonary shunt procedure were retrospectively analyzed. Demographic characteristics, preoperative, operative, and postoperative data of the patients were recorded. The Nakata indices of the patients were also noted before the procedure, as well as before the second stage of palliation or definitive repair. Four (40%) patients were operated as the first-step palliation for univentricular circulation. Six (60%) patients had well-developed ventricles and were palliated to be treated with total correction. The median follow-up after the procedure was 12 (range, 8 to 16) months. The mean systemic arterial saturation level at room air was 89.3±2.9% during follow-up. No mortality was observed in any patient. A central aortopulmonary shunt procedure provides a reliable antegrade blood flow with a relatively non-challenging surgical technique that offers sufficient growth for the hypoplastic and confluent central pulmonary arteries with a very low risk of shunt thrombosis and overflow.

Outcome of patients with tetralogy of Fallot with pulmonary atresia.

Tetralogy of Fallot patients with pulmonary atresia (TOFPA) have a largely varying source of pulmonary perfusion with often hypoplastic and even absent central pulmonary arteries. A retrospective single center study was undertaken to assess outcome of these patients regarding type of surgical procedures, long-term mortality, achievement of VSD closure and analysis of postoperative interventions. 76 consecutive patients with TOFPA operated between 01.01.2003 and 31.12.2019 are included in this single center study. Patients with ductus dependent pulmonary circulation underwent primary single stage full correction including VSD closure and right ventricular to pulmonary conduit implantation (RVPAC) or transanular patch reconstruction. Children with hypoplastic pulmonary arteries and MAPCAs without double supply were predominantly treated by unifocalization and RVPAC implantation. The follow up period ranges between 0 and 16,5 years. 31 patients (41%) underwent single stage full correction at a median age of 12 days, 15 patients could be treated by a transanular patch. 30 days mortality rate in this group was 6%. In the remaining 45 patients the VSD could not be closed during their first surgery which was performed at a median age of 89 days. A VSD closure was achieved later in 64% of these patients after median 178 days. 30 days mortality rate after the first surgery was 13% in this group. The estimated 10-year-survival rate after the first surgery is 80,5% ± 4,7% showing no significant difference between the groups with and without MAPCAs (p > 0,999). Median intervention-free interval (surgery and transcatheter intervention) after VSD closure was 1,7 ± 0,5 years [95% CI: 0,7-2,8 years]. A VSD closure could be achieved in 79% of the total cohort. In patients without MAPCAs this was possible at a significant earlier age (p < 0,01). Although patients without MAPCAs predominantly underwent single stage full correction at newborn age, the overall mortality rate and the interval until reintervention after VSD closure did not show significant differences between the two groups with and without MAPCAs. The high rate of proven genetic abnormalities (40%) with non-cardiac malformations did also pay its tribute to impaired life expectancy.

Echocardiographic findings in patients with tetralogy of fallot prior to total corrective surgery admitted at a tertiary care hospital.

Objective: To find out echocardiographic findings in patients with tetralogy of Fallot (TOF) prior to total corrective surgery admitted at a tertiary care hospital. Study Design: Cross-sectional study. Setting: Department of Pediatric Cardiology, National Institute of Cardiovascular Disease, Karachi. Period: January 2021 to December 2021. Material &amp; Methods: A total of 197 echocardiography confirmed TOF cases of both genders and age up to any years were included. Physical examination, chest radiography and electrocardiogram were done in each patient prior to transthoracic echocardiography (TTE) using Toshiba Aplio i600 using 5 Hz and 6 Hz transducers. Standard protocols were followed in all TTE procedures. Results: In a total of 197 patients with TOF, there were 121 (61.4%) male. Mean age was 8.36±10.12 years. Hypoplastic pulmonary arteries was the most frequent pulmonary artery abnormality observed in 30 (15.2%) cases. Thickened and domed pulmonic valve was the most common pulmonary valvular anomaly noted in 89 (45.2%). Associated “atrial septal defect (ASD)” was observed in 47 (23.9%) cases while “patent ductus arteriosus (PDA)” was seen in 83 (42.1%) patients. History of past “Blalock and Taussig (BT) Shunt” performed was found in 20 (10.2%) cases, out of which, 15 were functioning. Conclusion: Echocardiography is an inexpensive and safe approach to cardiac evaluation among patients of tetralogy of fallot. Hypoplastic pulmonary arteries was the most frequent pulmonary artery abnormality observed in tetralogy of Fallot patients. PDA was the most frequent associated abnormality followed by associated ASD.

Coexistence of transposition of the great arteries, coarctation of the aorta, and bilateral pulmonary artery hypoplasia.

Transposition of the great arteries is the most common cyanotic CHD in newborns. This CHD, in which the aorta arises from the right ventricle and the pulmonary artery from the left ventricle, is often accompanied by one or several defects such as atrial septal defect or patent foramen ovale, ventricular septal defect and patent ductus arteriosus, which allow the transition between both parallel circulations. Rarely, the disease may be accompanied by left ventricular outflow tract obstruction (subpulmonary obstruction) and coarctation of the aorta.We present a highly complicated and unusual transposition of the great arteries patient with critical aortic coarctation and hypoplastic pulmonary arteries with abnormal outflow and course.

VSD PA MAPCAS presenting late with hypoplastic pulmonary vasculature. Reply to letter to Editor: "Lesson learnt about right ventricle to pulmonary artery shunt for older children and young adults with ventricular septal defect, pulmonary atresia, and hypoplastic pulmonary arteries".

VSD PA MAPCAS presenting late with hypoplastic pulmonary vasculature. Reply to letter to Editor: "Lesson learnt about right ventricle to pulmonary artery shunt for older children and young adults with ventricular septal defect, pulmonary atresia, and hypoplastic pulmonary arteries".

Lesson learnt about right ventricle to pulmonary artery shunt for older children and young adults with ventricular septal defect, pulmonary atresia, and hypoplastic pulmonary arteries.

Lesson learnt about right ventricle to pulmonary artery shunt for older children and young adults with ventricular septal defect, pulmonary atresia, and hypoplastic pulmonary arteries.

Patch enlargement may not be a good strategy for treating tetralogy of Fallot with unbalanced pulmonary artery branches.

Our goal was to determine the optimal strategy for managing tetralogy of Fallot (TOF) with unbalanced pulmonary artery (PA) branches by investigating the different effects of PA plasty on the development of hypoplastic PA (HPA). A single-centre, retrospective analysis was carried out to compare the outcome of different PA plasty methods on the development of HPA in patients with TOF with unbalanced PA branches. Size and balance of the PA branches were used to evaluate the outcome of PA plasty. In the NATIVE group, 100% of the HPAs were well-developed and all PA branches became balanced, whereas in the PATCH and EXTENSION groups, the percentage of well-developed HPAs was 40% and 33%, respectively, and none of the PA branches were balanced. In addition, HPAs became atretic in 28% of the patients in the patch enlargement group. For TOF with unbalanced PA branches, patch enlargement may not be a good treatment strategy, because it reduces the growth potential of HPA and even causes iatrogenic atresia. Leaving the HPA in the native state without patch enlargement may be a good strategy.

Pulmonary Artery Pseudoaneurysm After Transcatheter Pulmonary Valve Replacement, a Novel Approach for Complication Management

Transcatheter pulmonary valve replacement (TPVR) using the SAPIEN 3 (Edwards Lifesciences) transcatheter heart valve is increasingly used to treat patients with right ventricular outflow tract (RVOT) dysfunction. Yet, TPVR in patients with calcified RVOT homografts remains challenging and carries a high risk of complications. We present a case of a dysfunctional 24-mm calcified RVOT homograft in a patient with a history of truncus arteriosus and hypoplastic branch pulmonary arteries.

Intrapulmonary artery septation for pulmonary artery growth in functionally univentricular hearts.

The pulmonary artery anatomy is one of the important determinants of Fontan completion and its outcomes in patients with functionally univentricular hearts. Despite several modifications to Fontan operation, unbalanced pulmonary arteries pose a significant challenge in this subset of patients. Intrapulmonary artery septation is a technique, developed to rehabilitate the unilateral hypoplastic pulmonary artery following various initial palliative procedures in functionally univentricular hearts. Literature is sparse on this technique. This article reviews the basic concepts and literature on intrapulmonary artery septation. We also describe our experience with modified intrapulmonary artery septation.

Application of Vessel Navigator™ fusion imaging software in a complex transcatheter palliation of Tetralogy of Fallot with pulmonary atresia

Extreme pulmonary artery hypoplasia in cyanotic malformations precludes palliative surgeries. When aortopulmonary collaterals (APC) in such patients are also hypoplastic, their unifocalization to create a neopulmonary vasculature is also hampered. Stent angioplasty of the outflow or collateral arteries may reduce hypoxia but is challenging in tortuous and atretic tracts. Fusion imaging overlays anatomical data from computed tomography during adult structural interventions, but its use is not often reported in young children with complex cyanotic malformations. This report shows utility of fusion imaging in pulmonary atresia with extremely hypoplastic pulmonary arteries and stenotic APC to guide stenting of outflow tract and collaterals.

Ascending aortic extension to increase aortopulmonary space after comprehensive stage II palliation.

Aortic reconstruction at the time of the comprehensive stage II (CSII) procedure can be complicated by compression within the aortopulmonary space resulting in airway or pulmonary artery narrowing. We describe our experience with 2 patients with hypoplastic left heart syndrome and pulmonary artery stenosis after the CSII procedure. Both patients underwent an aortic extension with a Hemashield interposition graft to open up the aortopulmonary space. The patients were discharged from the hospital. In all cases the aortopulmonary space was enlarged, and the pulmonary arteries and airway were free from compression. Aortic extension is an option to be considered in children with pulmonary artery compression who previously had a CSII procedure.