Pulmonary Artery Continuity Research Articles

Primary pulmonary artery reconstruction for functional single ventricle with absent central pulmonary artery and bilateral patent ductus arteriosus.

This study aimed to evaluate and discuss the outcomes of creating a single systemic-pulmonary shunt and reconstruction of the pulmonary artery continuity in patients with a single functional ventricle, absent central pulmonary artery, and bilateral patent ductus arteriosus. Six infants diagnosed with a functional single ventricle, absent central pulmonary artery, and bilateral patent ductus arteriosus were treated by creating a single systemic-pulmonary shunt and reconstructing the pulmonary artery continuity (primary operation) between January 2010 and September 2020. Pulmonary artery continuity was ensured using the remnant pulmonary artery and an autologous pericardial patch in five patients and a rolled autologous pericardium in one patient. All patients eventually underwent total cavopulmonary connection. Two patients underwent intrapulmonary artery septation before Glenn or total cavopulmonary connection procedure. The median follow-up period was 9.02years (interquartile range, 3.90-9.53). No late deaths were observed. Our strategy of establishing a single systemic-pulmonary shunt with reconstruction of the pulmonary artery continuity was useful for treating patients with a functional single ventricle with absent central pulmonary artery and bilateral patent ductus arteriosus. This procedure helped accomplish pulmonary artery growth and ensured an appropriate volume load after total cavopulmonary connection.

Morphological changes and number of candidates for transcatheter pulmonary valve implantation in conduits involving heterograft and artificial material.

Heterograft and artificial materials have been used for extracardiac conduit implantation to create right ventricular (RV) to pulmonary artery (PA) continuity for biventricular repair in Japan because of the limited availability of homograft valves. However, few studies have examined morphological changes and number of candidates for transcatheter pulmonary valve implantation (TPVI) in which the conduit includes more than one type of material. Overall, 88 patients who underwent biventricular repair with an external conduit were included in this evaluation. Based on catheterization data and surgical records, we estimated morphological change in the RV outflow tract for each material and the number of candidates for Melody valve implantation based on premarket approval application criteria established by the U.S. Food and Drug Administration. There were 63 candidates for TPVI (72%, 63/88). Median anteroposterior and lateral diameter of the RV outflow tract was 20.4mm (range 9.0-41.5) and 17.8mm (range 9.5-34.9), respectively. Bovine pericardium tended to dilate by 11.2%. Polytetrafluoroethylene (ePTFE), homograft, and Dacron polyethylene terephthalate (PET) tended to become stenotic by 11.1%, 28.0%, and 13.4%, respectively. While ePTFE (27/33, 82%) and Dacron PET (2/2, 100%) were highly suitable for TPVI, bovine pericardium (32/48, 67%) was less suitable. In Japan, many patients with hemodynamic indications for TPVI following extracardiac conduit implantation to create RV to PA continuity may also meet the morphological indications.

Right ventricular outflow reconstruction with handmade valve conduit - A short experience from a developing country. Case series

ObjectivesRight ventricular outflow tract continuity abnormalities are one of the most commonly encountered entities in the field of congenital cardiac surgery. Various strategies including homograft, valve conduit, Contegra are used to restore continuity between right ventricle and pulmonary artery. In countries like Pakistan these may not be easily available and affordable. We report the experience of our short observational study of using a handmade trileaflet valve conduit to reconstruct the right ventricular outflow tract. MethodologyFrom September 2015 to December 2016, a total of 15 patients with different congenital heart diseases underwent open-heart surgery at our institute. Restoration of right ventricular to pulmonary artery continuity was achieved using handmade valve conduit utilizing bovine pericardium and thin sheet PTFE sheets (0.1 mm) as conduit and valve respectively. ResultsPatients ranged from 1 to 16 years. Seven patients had previous palliation including 4 blalock taussig (BT) Shunts and 3 pulmonary artery (PA) banding. Postoperative complications were observed in 4 patient including 2 in hospital deaths and 2 required interventions. One patient developed aneurysm at RV- conduit junction requiring surgical repair and the other underwent conduit dilatation for moderate to severe stenosis (gradient 60 mmHg). No significant regurgitation was observed in this series. Overall postoperative gradients were stable with mean gradient 25.3 mmHg (8 mmhg - 60 mmHg). ConclusionThe use of handmade valve conduits has acceptable morbidity and mortality. These are cost effective alternatives in this part of the world, where well-established conduits have cost implications and uncertain availability.

Right Ventricular Outflow Tract Reconstruction in Infant Truncus Arteriosus: A 37-year Experience

Multiple conduits for right ventricular outflow tract reconstruction exist, although the ideal conduit that maximizes outcomes remains controversial. We evaluated long-term outcomes and compared conduits for right ventricular outflow tract reconstruction in children with truncus arteriosus. Records of patients who underwent truncus arteriosus repair at our institution between 1981 and 2018 were retrospectively reviewed. Primary outcomes included survival and freedom from catheter reintervention or reoperation. Secondary analyses evaluated the effect of comorbidity, operation era, conduit type, and conduit size. One hundred patients met inclusion criteria. Median follow-up time was 15.6 years (interquartile range, 5.3-22.2). Actuarial survival at 30 days, 5 years, 10 years, and 15 years was 85%, 72%, 72%, and 68%, respectively. Early mortality was associated with concomitant interrupted aortic arch (hazard ratio, 5.4; 95% confidence interval, 1.7-17.4; P= .005). Median time to surgical reoperation was 4.6 years (interquartile range, 2.9-6.8; n=58). Right ventricle to pulmonary artery continuity was established with an aortic homograft (n= 14), pulmonary homograft (n= 41), or bovine jugular vein conduit (n= 36) in most cases. Multivariate analysis revealed longer freedom from reoperation with the bovine jugular vein conduit compared with the aortic homograft (hazard ratio, 3.1; 95% confidence interval, 1.3-7.7; P= .02) with no difference compared with the pulmonary homograft. Larger conduit size was associated with longer freedom from reoperation (hazard ratio, 0.7; 95% confidence interval, 0.6-0.9; P < .001). The bovine jugular vein conduit is a favorable conduit for right ventricular outflow tract reconstruction in patients with truncus arteriosus. Concomitant interrupted aortic arch is a risk factor for early mortality.

Modified Repair of Type I and II Truncus Arteriosus Limits Early Right Ventricular Outflow Tract Reoperation

Repair of truncus arteriosus often requires early right ventricular outflow tract (RVOT) reoperation. Using a modified repair, the branch pulmonary arteries are left in situ, which may avoid earlier RVOT reoperation. We hypothesized that our modified repair for type I and II truncus arteriosus would extend the time to RVOT reoperation. Infants with truncus arteriosus were divided into 2 groups: (1) traditional technique where the branch pulmonary arteries are excised from the truncal root, or (2) modified repair where the branch pulmonary arteries are left in situ and septated from the truncal root. Regardless of the approach, a bioprosthetic conduit or homograft was used to establish right ventricular to pulmonary artery continuity. Follow-up pulmonary artery angiograms were used to assess for branch pulmonary artery stenosis. From 54 infants (modified repair: 33, traditional technique: 21), there were no significant differences in age at repair, gender, or type of truncus arteriosus. With 100% follow-up, use of the modified repair resulted in a lower rate of branch pulmonary artery stenosis, and greater freedom from surgical branch pulmonary arterioplasty. Five- and 10-year freedom from RVOT reoperation (5 years: modified-81.5% vs traditional-30.5%, P = 0.004; 10 years: modified-53.3% vs traditional-30.5%, P = 0.01) favored the modified repair. Cox regression analysis demonstrated that the modified repair was associated with an independently lower risk for RVOT reoperation (hazard ratio: 0.08, confidence interval: 0.01, 0.75, P = 0.02). Thus, maintaining the branch pulmonary artery architecture resulted in greater freedom from RVOT reoperation.

Fresh Pericardial Valved Conduit for Reconstruction of Right Ventricular Outflow Tract in Tetralogy of Fallot with Pulmonary Stenosis or Pulmonary Atresia: Early Results

Objective: To study early results of handmade fresh (autologous/homologous) pericardial valved conduit in achieving right ventricle to pulmonary artery continuity.

Fresh Pericardial Valved Conduit for Reconstruction of Right Ventricular Outflow Tract in Tetralogy of Fallot with Pulmonary Stenosis or Pulmonary Atresia—Early Results

Objective: To study early results of hand made fresh (autologous/homologous) pericardial valved conduit in achieving right ventricle to pulmonary artery continuity. Method: Between November 2014 and September 2015, 19 cases, with diagnosis of Tetralogy of Fallot with Pulmonary stenosis (PS) or Pulmonary atresia (PA) underwent intracardiac repair and Right Ventricular Outflow Tract (RVOT) reconstruction with hand made fresh [autologous (n = 2)/ homologous (n = 17)] pericardial valved conduit. Mean age of the patients at time of surgery was 6.37 years (range 3 months to 18 years), mean weight was 18.52 kilograms (range 6 kg to 40 kg) and mean size of the conduit was 20.7 mm (range 16 mm to 24 mm). Results: All patients had a smooth post-operative course, with mean ICU (Intensive Care Unit) stay of 3.6 days (range 3 days to 6 days) and mean post-operative hospital stay 8.5 days (range 7 days to 16 days). Intra-operative and Post-operative echocardiography revealed moderate Pulmonary regurgitation (PR) in one patient, mild PR in 5 patients and no or trace PR in 13 patients. No patient has developed conduit stenosis or calcification till now. Conclusion: Autologous or homologous pericardial valved conduit provides good early results and is especially suitable for developing world because of zero cost. Long term usefulness of such option remains to be confirmed in terms of dilation, calcification and freedom from intervention.

The Yasui operation for patients with adequate-sized ventricles and ventricular septal defect associated with obstructions of the aortic arch and left ventricular outflow tract

To review the surgical outcome of the Yasui operation in patients with adequate-sized ventricles and ventricular septal defect (VSD) associated with obstructions of the aortic arch and left ventricular outflow tract (LVOT). Since 1985, 17 patients have undergone the Yasui operation at our institution. Interrupted aortic arch was present in 11 patients and coarctation of the aorta/hypoplastic arch was present in 6. Twelve patients had aortic stenosis, and 5 patients had aortic atresia. The minimum diameter of the LVOT and the z-score in patients with aortic stenosis were 3.7 ± 0.4 mm and -9.2 ± 1.2, respectively. Primary repair was performed in 6 patients, and 11 patients were staged, with bilateral pulmonary artery banding (PAB) in 8, arch repair with PAB in 2 and Norwood operation in 1. The mean age and body weight at the time of the Yasui operation was 4.7 ± 5.3 months and 4.5 ± 1.8 kg, respectively. The ascending aorta and aortic arch were reconstructed by Damus-Kaye-Stansel (DKS) anastomosis with graft interposition in 2, DKS with direct anastomosis in 6 and Norwood-type reconstruction in 9. VSD was enlarged in 6 patients. Right ventricle to pulmonary artery continuity was established with a valved conduit in 14 patients, the Lecompte manoeuvre in 2 patients and another method in 1 patient. The mean duration of the follow-up was 7.6 ± 9.2 years. There was 1 early death due to myocardial infarction and 1 late death due to non-cardiac cause. The actuarial survival at 10 years was 87.8%. Six patients underwent reoperation, including 5 conduit exchanges, 2 LVOT repairs and 2 aortic arch repairs. The freedom from reoperation for all causes at 5 and 10 years were 71.3 and 28.5%, respectively. In the last echo study, LVOT flow velocity was 1.2 ± 0.8 m/s, and neoaortic valve regurgitation was mild in 1 patient and trivial or absent in the remaining patients. The results of the Yasui operation were excellent, showing low mortality and good mid-term left ventricular function without outflow tract stenosis or neoaortic valve insufficiency. Bilateral PAB as initial palliation is a useful option in symptomatic neonates.

Reconstruction of right ventricular outflow tract in neonates and infants using valved cryopreserved femoral vein homografts

Aortic or pulmonary homografts (A/PHs) are common biomaterials used for restoration of right ventricle to pulmonary artery continuity for repair of various congenital heart defects. The smaller sized homografts required for early primary repair in neonates and infants are prone to early failure and are in short supply. Due to these limitations, since 2008 it has been our preference to use valved segments of cryopreserved femoral vein homograft (cFVH) for right ventricle to pulmonary artery reconstruction. This study was undertaken to assess the performance of cFVH compared with A/PH in neonates and infants. A retrospective review of all infants and neonates who underwent biventricular early primary repair with right ventricle to pulmonary artery reconstruction using homograft conduits at a single center was conducted. Patients who received cFVH constituted the study group, whereas all other patients received A/PH and formed the control group. Patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collaterals who had conduits placed to promote pulmonary artery growth or to unifocalized pulmonary vasculature were excluded from the study because they have different clinical indications for reoperation and reintervention. Demographic, anatomical, perioperative, and follow-up variables were compared between the groups using univariate and multivariable Cox regression analyses. Kaplan-Meier analysis and log-rank tests were used to identify intergroup differences in freedom from catheter intervention, reoperation, or overall freedom from reintervention (catheter and/or surgical). A total of 36 patients (20 cFVH and 16 A/PH) were included in the study. There were no intergroup differences in the demographic, anatomic, and perioperative variables, except for significantly shorter aortic crossclamp time in the cFVH group. Univariate analysis revealed a higher catheter reintervention rate as well as higher reoperation rate in the A/PH group. Multivariate Cox regression correcting for the intergroup differences in the length of follow-up revealed comparable freedom from catheter intervention, freedom from reoperation, or freedom from either intervention in the cFVH and the A/PH groups. Valved femoral vein homografts have comparable short- and intermediate-term performance to A/PHs for right ventricular outflow tract reconstruction and are an attractive alternative to other small conduits for use in neonates and infants.

Left Main Coronary Artery Compression Long Term After Repair of Conotruncal Lesions: The Bow String Conduit

We report 4 cases of left main coronary artery (LMCA) compression after remote repair of conotruncal lesions and their successful surgical management.

Mid-Term Results After Correction of Type I and Type II Persistent Truncus Arteriosus in Older Patients

This study aims to analyze long-term results after correction of type I and type II truncus arteriosus in older patients operated in one institution over five years. Between 2006 and 2010, 12 patients, median age 4 years, underwent repair of truncus arteriosus. Repair with reconstruction of the right ventricular to pulmonary artery continuity was performed using a valved conduit in 12 patients. There was no early mortality. All patients are alive with their original conduit 0.6 to 5 years after correction. No patients required reoperations for conduit dysfunction. Recent clinical examination was undertaken in all patients and they are in good condition. Though mean age at operation was higher in this study than published results, the operation should be performed if the pulmonary vascular resistance is under 8 units.m(2) before operation.

Long-Term Follow-Up of Persistent Truncus Arteriosus: Kuwait Experience

Objective: To evaluate the long-term results of patients in Kuwait who were operated for persistent truncus arteriosus (PTA). Subjects and Methods: The following data were collected for retrospective analysis from 24 medical records of consecutive patients with PTA in Kuwait between August 1993 and August 2009: demographics, morphology, management and outcome. Major associated abnormalities included interrupted aortic arch in 1 patient and abnormal coronary artery anatomy in 2. Results: Of the 24 patients, 16 underwent total intracardiac repair. The age at operation ranged from 15 days to 5 years (mean 166.19 ± 438.63 days) and weight ranged from 2.5 to 15 kg (mean 4.3 ± 3.01 kg). The right ventricle to pulmonary artery continuity was established with aortic homograft in 11, pulmonary homograft in 4 and by implantation of a Contegra conduit in 1 patient. Four patients had moderate truncal valve regurgitation requiring concomitant truncal valve repair. After a mean follow-up period of 81.81 ± 61.58 months (range 3–166) there was no death. Eight of the 16 (50%) patients underwent redo homograft operations. One patient who had concomitant truncal valve repair subsequently underwent aortic valve replacement. Conclusion: The data showed that complete repair of PTA in the neonatal and early infancy period was the treatment with the best potential for survival. The homograft remained one of the conduits of choice to establish continuity between the right ventricle and the pulmonary artery in spite of the high incidence of conduit redo operations.

Invited Commentary

Invited Commentary

Technique for the Repair of Truncus Arteriosus to Maintain Pulmonary Artery Architecture

Technique for the Repair of Truncus Arteriosus to Maintain Pulmonary Artery Architecture

Modified Repair of Truncus Arteriosus to Maintain Pulmonary Artery Architecture

Neonatal surgical repair for truncus arteriosus historically involves removing the pulmonary arteries from the truncal root, closing the ventricular septal defect, and creating right ventricular to pulmonary artery continuity. Unfortunately, early reintervention is frequently required for conduit failure and proximal branch pulmonary artery stenosis. We present a technique that preserves the pulmonary artery architecture, keeping the pulmonary arteries in their native position. This technique has been applied to 16 patients and appears to decrease proximal branch pulmonary artery stenosis, thereby extending conduit longevity and increasing the freedom from early reintervention.

Long-term results after correction of persistent truncus arteriosus in 83 patients

This study aims to analyse long-term results after correction of truncus arteriosus in all patients operated in one institution over 28 years. Between 1981 and 2009, 83 patients, median age 54 days, underwent repair of truncus arteriosus. Interrupted aortic arch was present in 14 (17%), severe truncal valve insufficiency in 10 (12%) and non-confluent pulmonary arteries in five (6%) patients. Repair with reconstruction of the right ventricular to pulmonary artery continuity was performed using a valved conduit in 80, and other methods in three patients. At the same time, correction of interrupted aortic arch was done in 14 and truncal valve repair in eight patients. Survivors were repeatedly examined echocardiographically for assessment of residual heart lesions. The early mortality was 19 (23%). Out of 35 patients operated between 1981 and 1996, 17 (46%) died, and out of 48 patients operated between 1997 and 2009, two (4%) died. Operation before 1997 (p=0.001) and aortic cross-clamping time >90min (p=0.009) were found to be risk factors of death. Eight (10%) patients died late, a median of 68 days after surgery. Fifty-seven (69%) patients were followed for 10.9 + or - 6.7 years. Three (4%) patients were lost. Twenty-five (30%) patients are alive with their original conduit 7.5 + or - 5.2 years after correction. Twenty-eight patients required 41 re-operations for conduit dysfunction with first replacement at mean 5.8 + or - 4.1 (range 0.1-14.1 years) years after correction. Nine (11%) patients required 12 truncal valve replacements. Eleven (13%) patients required balloon dilatation or stent for conduit obstruction, pulmonary branch stenosis, aortic arch obstruction or stenosis of vena cava. Recent clinical examination was undertaken in 53 (64%) patients and 49 (59% or 77% of early survivors) are in good/very good condition. Truncus arteriosus remains a challenging heart disease. With growing experience, the early mortality decreased to 4%, but numerous re-interventions for conduit obstruction, pulmonary branch stenosis and truncal valve insufficiency are required. Surgery before 1997 and prolonged cross-clamping were risk factors of death. Pulmonary homografts had the best re-intervention-free survival. Statistically, however, the difference between conduits was not significant. Dysplastic valve and truncal valve insufficiency represent risk factors presenting the need for truncal valve replacement.

Outcomes following non-valved autologous reconstruction of the right ventricular outflow tract in neonates and infants

Controversy surrounds the optimal method of establishing right ventricle to pulmonary artery continuity in neonates and infants with congenital heart disease. We reviewed our experience with non-valved autologous reconstruction of the right ventricular outflow tract to determine mid-term outcome and risk factors for reintervention. Between 1998 and 2006, 34 consecutive patients underwent non-valved autologous right ventricular outflow tract reconstruction. The need for postoperative catheter-based intervention or reoperation was assessed using relevant patient and procedure-related variables. Diagnoses included tetralogy of Fallot with anomalous coronary (n=3), tetralogy of Fallot with pulmonary atresia (n=10), truncus arteriosus communis (n=15), and other (n=6). Median age at surgery was 5 days (1-270 days). Twenty-six (76%) patients were neonates. Median weight was 3.1kg (1.8-7.3kg). At a median follow-up of 43 months (1-90 months), 15 (50%) patients underwent reoperation and 7 (23%) underwent catheter-based intervention, with a total of 16 (53%) undergoing either reoperation or catheter-based intervention. Kaplan-Meier freedom from reintervention at 6 months, 1 year, 3 years, and 5 years was 67%, 47%, 47%, and 35% for truncus arteriosus versus 87%, 82%, 68%, and 65% for diagnoses other than truncus arteriosus (p=0.05). Mid-term outcome following non-valved autologous reconstruction of the right ventricular outflow tract is satisfactory and constitutes a sound alternative to the use of small-diameter conduits in neonates and infants. In our hands, this strategy favors certain anatomic subtypes. Non-truncus patients have significantly lower rates of reintervention. Technical details associated with the anatomical reconstruction of the posterior autologous pathway may play an important role in outcomes.

First-stage angioplasty for a single ventricle with pulmonary artery coarctation

We report first-stage palliation consisting of pulmonary artery angioplasty and a systemic-to-pulmonary shunt using a minimized cardiopulmonary bypass technique performed with modified ultrafiltration for two patients with a single ventricle, pulmonary atresia, patent ductus arteriosus, and pulmonary coarctation during early infancy. Postoperative early extubation (15 and 18 h) and bilateral pulmonary artery growth before the second stage (Nakata indexes, in mm2/m2: right 94, left 53; and right 209, left 70) were experienced. Less-invasive pulmonary artery continuity reconstruction at an early stage is advantageous for low-weight patients with a single ventricle and pulmonary coarctation.

Truncus Arteriosus With Interrupted Aortic Arch: Successful Repair Using Modified Cardiopulmonary Bypass and Surgical Techniques

A neonate with truncus arteriosus (type 1) and interrupted aortic arch (type A) associated with an excessively large gap between interrupted aortic segments underwent successful reconstruction of the aortic arch with a partial subclavian flap aortoplasty plus bovine jugular patch (Contegra 200, Medtronic, Inc, Minneapolis, MN) using continuous selective low-flow cardiopulmonary bypass without circulatory arrest. The ventricular septal defect was closed with a Dacron (IMPRA, Inc, Tempe, AZ) patch, and a Contegra prosthesis was used to re-establish right ventricle to pulmonary artery continuity. At an 18-month follow-up, the patient was free of symptoms with normal development. Echocardiography revealed a widely patent aortic arch and an unobstructed right ventricle to pulmonary artery connection.

Agenesia isolada da artéria pulmonar direita ou esquerda: avaliação da evolução natural e a longo prazo, após intervenção corretiva

Unilateral pulmonary artery agenesis is an uncommon isolated anomaly and since 1978 only 119 cases have been reported. In general the condition presents as pulmonary hypertension (PH) in children and hemoptysis in adults. Interventions such as pulmonary artery reconstruction and lobectomies were performed in 17% of the cases. We analyzed four of these cases, two in natural evolution and two with late term PH regression after surgical correction. Three 22,10 and 35 month old male children and one 20 month old female child were included in the study. The 22 month old presented right-sided heart failure (RHF) and cyanosis; the 10 month old presented RHF and the other two presented exertion fatigue. All had PH symptoms, right ventricular strain on the EKG and cardiomegaly. Cardiac catheterization showed systemic pressures in the contralateral pulmonary artery, with right-sided agenesis in three of the children and left-sided agenesis in one child. Surgical correction of pulmonary artery continuity was possible in the 22 month old and 10 month old using a 7 mm diameter Goretex conduit between the pulmonary arteries up to the hypoplastic contralateral pulmonary hilum. There was early and late regression of the PH signs and the children remained stable during follow-up to the ages of 7 and 2.5 years, respectively. The pressure ratio between the left and right ventricles was 30 and 40%, in both cases. Pulmonary perfusion increased from 8 to 44% and from 8 to 23%, in the two cases. The same procedure was scheduled for the other patients. This technique has become the operation of choice for similar cases, that are rarely described in literature, even in the presence of severe PH and contralateral pulmonary artery hypoplasia.