Surgical management of pulmonary atresia with intact ventricular septum

Pulmonary Atresia With an Intact Ventricular Septum: Preoperative Physiology, Imaging, and Management

Pulmonary atresia with intact ventricular septum (PA-IVS) is a rare complex cyanotic congenital heart disease with heterogeneous morphological variation. Prenatal diagnosis allows for developing a safe plan for delivery and postnatal management. While transthoracic echocardiography allows for detailed delineation of the cardiac anatomy, additional imaging modalities such as computed tomography, magnetic resonance imaging, and catheterization may be necessary to further outline features of the cardiac anatomy, specifically coronary artery anatomy. The size of the tricuspid valve and right ventricular cavity as well as the presence of right ventricle–dependent coronary circulation help to dichotomize between biventricular repair versus univentricular palliation or heart transplantation, as well as predicting the expected survival. The delineation and understanding of these features help to dictate both medical and surgical management.

Biventricular repair versus uni-ventricular repair for pulmonary atresia with intact ventrical septum: A systematic review

The management of pulmonary atresia with intact ventricular septum (PA/IVS) remains controversial. The goal of separating systematic and pulmonary circulation can be achieved by biventricular or uni-ventricular (Fontan or one and a half ventricle repair) strategies. Although outcomes have been improved, these surgical procedures are still associated with high mortality and morbidity. An optimal strategy for definitive repair has yet to be defined. We searched databases for genetically randomized controlled trials (RCTs) comparing biventricular with uni-ventricular repair for patient with PA/IVS. Data extraction and quality assessment were performed following the guidelines of the Cochrane Collaboration. Primary outcome measures were overall survival, and secondary criteria included exercise function, arrhythmia-free survival and treatment-related mortality. A total number of 669 primary citations were screened for relevant studies. Detailed analysis revealed that no RCTs were found to adequately address the research question and no systematic meta-analysis would have been carried out. Nevertheless, several retrospective analyses and case series addressed the question of finding right balance between biventricular and uni-ventricular repair for patient with PA/IVS. In this review, we will discuss the currently available data.

Transcatheter management of neonates with pulmonary atresia with intact ventricular septum: a single center experience from Turkey

Pulmonary atresia with intact ventricular septum (PAIVS) is characterized by a broad spectrum of heterogeneous morphologies. Perforation of the atretic valve, balloon dilatation, and stenting of the patent ductus arteriosus are the percutaneous techniques that are used with increasing frequency in our clinic as well. They have some advantages over surgery, including short hospital stay and short intensive care unit stay. The main goal of the primary interventional approach is to avoid surgery. However, a group of patients with PAIVS still need surgery due to poor right ventricular growth. Therefore, the final achievement of the initial percutaneous treatment strategies is still debatable. In this article, we present the early- and mid-term results of the percutaneous approach utilized at our clinic in order to investigate the final effects of interventional therapy according to initial morphology. Between May 2010 and May 2012, 15 neonates diagnosed with PAIVS underwent transcatheter intervention. Detailed echocardiographic examination focused on right ventricle size, and tricuspid valve morphology and coronary sinusoids were performed in all the patients before the intervention. Nine of the patients were boys and six were girls. The mean age was 11.40 ± 12.87 days and mean weight was 3.34 ± 0.46 kg. Only one procedure-related mortality occurred. The mean follow-up period was 10.05 ± 3.42 months (1-26 months). The mean duration of intensive care was 7.19 ± 5.14 days. The mean follow-up time was 10.05 ± 3.42 months. After this period, survival rate was 66% (10/15). Two of the patients achieved biventricular physiology after pulmonary valve perforation. Two patients still have univentricular physiology. Six patients have been followed as a one and half ventricle repair candidate. Five out of 15 patients had stent patency during 6 months of follow-up, while restenosis developed in one patient (1/5, 20%), who had undergone the Glenn operation at 5 months of age. Transcatheter management for PAIVS is a feasible, safe, and effective primary palliative treatment in newborns. Shunt surgery may be considered in cases where cyanosis occurs despite transcatheter intervention. Right ventricular size determines the type of intervention. The early outcomes can be comparable with surgical palliation. However, a group of PAIVS, particularly with severe right ventricular hypoplasia, needs surgery even after a successful primary percutaneous intervention.

Pulmonary atresia with intact ventricular septum causing severe left ventricular outflow tract obstruction

We describe an infant with pulmonary atresia with intact ventricular septum (PAIVS) and severe left ventricular outflow tract (LVOT) obstruction secondary to a suprasystemic right ventricle causing leftward displacement of the interventricular septum. Imaging demonstrated an aneurysmal dilation at the base of the proximal main pulmonary artery (MPA) with no forward flow from the right ventricle. During transannular patch and central shunt placement, the communication between the pulmonary artery and the right ventricle was enlarged to ensure adequate decompression. We report this successful palliation and resulting complete elimination of the LVOT obstruction in a very unique presentation of PAIVS in a newborn.

Successful Management of Patients With Pulmonary Atresia With Intact Ventricular Septum Using a Three Tier Grading System for Right Ventricular Hypoplasia

BACKGROUND

We sought to validate a simple grading scheme for right ventricular hypoplasia in determining suitability for a biventricular repair.

METHODS

We reviewed the medical records for 106 patients with pulmonary atresia-intact ventricular septum (PA-IVS) treated between 1982 and 2001. Over this period, children were assigned to mild (> 2/3 normal size, 23.7% of patients), moderate (1/3 to 2/3, 41.2%), or severe (1/3, 35.1%) right ventricular hypoplasia, and this grouping, along with severity of coronary anomalies (45% right ventricle to coronary fistulae, 16% with right ventricle dependent coronary circulation [RVDCC]), triaged children to eventual single ventricle (severe) or two-ventricle (mild or moderate) repair.

RESULTS

Actuarial 10-year survival was 86.3% with mortality predicted by severe hypoplasia (odds ratio [OR] 12.9, p < 0.001), RVDCC (OR 15.0, p < 0.001), and non-Caucasian race (OR 10.7, p < 0.001). Multivariate analysis with a Cox proportional hazards model confirmed only RVDCC (risk ratio [RR] 10.9, p = 0.0009} and non-Caucasian race (RR 6.9, p = 0.007) as significant. Although not an independent risk factor for survival, the degree of hypoplasia was the most important determinant for definitive repair. Severe hypoplasia virtually precluded two-ventricle repair (OR 33.1, p < 0.001 by chi2 analysis) and was the strongest risk factor for a one-ventricle system (OR 78.7, p < 0.001). Actuarial survival after either repair was 91%, and no biventricular repair later converted to a Fontan system.

CONCLUSIONS

Surgical management of patients based on this three tier grade for right ventricular hypoplasia results in excellent survival and correctly predicts patients destined for eventual Fontan and biventricular repair.

Pulmonary atresia with intact ventricular septum: management of, and outcomes for, a cohort of 210 consecutive patients

OBJECTIVES

We sought to determine trends, and outcomes, for a cohort of patients with pulmonary atresia with intact ventricular septum born between 1965 and 1998.

BACKGROUND

Pulmonary atresia with intact ventricular septum is a complex lesion that remains a therapeutic challenge, particularly regarding the suitability for biventricular repair.

METHODS

We identified 210 consecutive patients, and reviewed their medical records, initial angiograms, and echocardiograms, along with the relevant surgical and pathology reports.

RESULTS

The mean initial Z-score for the diameter of the tricuspid valve was -0.99 +/- 1.95, with Ebstein's malformation in 8%. A right ventricular dependent coronary arterial circulation was found in 23%. The proportion of patients who received treatment increased over time, although placement of an arterial shunt was the predominant initial procedure throughout the experience. At the last follow-up, 107 patients had not reached the planned final stage of their repair, and 79% of these had died. Of the 103 reaching the final stage of planned repair, 58 had undergone attempted biventricular repair, with 34% dying; 14 had undergone attempted one and a half ventricular repair, with 7% dying, and 31 had undergone attempted functionally univentricular repair, with 10% dying. Overall, survival was 57% at the age of 1 year, 48% at 5 years, and 43% at 10 years. Survival improved over time, with survival of 75% at 1 year, and 67% at 5 years, for patients born between 1992 and 1998. An earlier date of birth, the presence of Ebstein's malformation, and prematurity were all significant independent factors associated with decreased survival. A greater severity of coronary arterial abnormalities was significantly associated with a greater likelihood of left ventricular dysfunction during follow-up.

CONCLUSIONS

The outcomes for patients born with pulmonary atresia with intact ventricular septum have improved over time, albeit that careful initial management, and better selection, is still indicated for those planned to undergo biventricular repair.

Pulmonary atresia with intact ventricular septum and antenatal left ventricular failure

Pulmonary atresia with intact ventricular septum has been described extensively, and it is recognized that associated abnormalities of the coronary arteries may cause ischemia. We describe a fetus, diagnosed antenatally as having pulmonary atresia with intact ventricular septum and severe hypoplasia of the right ventricle, who developed severe left ventricular dysfunction. We hypothesize that this is due to reduced coronary blood flow because of falling right ventricular volume in the presence of complete right ventricular coronary arterial dependence.