Pulmonary ductal coarctation and left pulmonary artery interruption; pathology and role of neural crest and second heart field during development.

OBJECTIVES: In congenital heart malformations with pulmonary stenosis to atresia an abnormal lateral ductus arteriosus to left pulmonary artery connection can lead to a localised narrowing (pulmonary ductal coarctation) or even interruption We investigated embryonic remodelling and pathogenesis of this area. MATERIAL AND METHODS: Normal development was studied in WntCre reporter mice (E10.0-12.5) for neural crest cells and Nkx2.5 immunostaining for second heart field cells. Data were compared to stage matched human embryos and a VEGF120/120 mutant mouse strain developing pulmonary atresia. RESULTS: Normal mouse and human embryos showed that the mid-pharyngeal endothelial plexus, connected side-ways to the 6th pharyngeal arch artery. The ventral segment formed the proximal pulmonary artery. The dorsal segment (future DA) was solely surrounded by neural crest cells. The ventral segment had a dual outer lining with neural crest and second heart field cells, while the distal pulmonary artery was covered by none of these cells. The asymmetric contribution of second heart field to the future pulmonary trunk on the left side of the aortic sac (so-called pulmonary push) was evident. The ventral segment became incorporated into the pulmonary trunk leading to a separate connection of the left and right pulmonary arteries. The VEGF120/120 embryos showed a stunted pulmonary push and a variety of vascular anomalies. SUMMARY: Side-way connection of the DA to the left pulmonary artery is a congenital anomaly. The primary problem is a stunted development of the pulmonary push leading to pulmonary stenosis/atresia and a subsequent lack of proper incorporation of the ventral segment into the aortic sac. Clinically, the aberrant smooth muscle tissue of the ductus arteriosus should be addressed to prohibit development of severe pulmonary ductal coarctation or even interruption of the left pulmonary artery.

Anomalous Left Coronary Artery From Pulmonary Artery in a Baby With Pulmonary Atresia, Intact Ventricular Septum.

A baby with pulmonary atresia with intact ventricular septum and hypoplastic right ventricle, with suspected right ventricle to coronary communications, was operated on for placing an aortopulmonary shunt. Postoperatively, the baby deteriorated with features of myocardial ischemia. Postmortem examination revealed anomalous origin of left coronary artery from pulmonary artery that caused significant coronary ischemia on ligation of the ductus arteriosus. Although coronary anomalies, including right ventricle dependent coronary circulation, has been well described, this is the first report of anomalous origin of coronary artery from pulmonary artery in a baby with pulmonary atresia and intact ventricular septum.

Anatomy of the retro-oesophageal major aortopulmonary collateral arteries in patients with pulmonary atresia with ventricular septal defect: results from preoperative CTA.

OBJECTIVES: To assess the frequency and anatomy of retro-oesophageal aortopulmonary collateral arteries (REMs) in patients with pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries (PA-VSD-MAPCAs). METHODS: A total of 130 consecutive PA-VSD-MAPCA patients with preoperative CT angiography (CTA) data who underwent cardiac surgery were included. A detailed analysis of MAPCA anatomy was performed using CTA. RESULTS: A REM was identified in 82/130 included patients (63 %). A total of 277 MAPCAs were observed in these 82 patients and were divided into groups based on REM status: REM (n=94) and non-REM (n=183). Compared with non-REMs, REMs originated at a lower level and tended to originate from the lateral side of the aorta (all p<0.01). REMs had a higher probability of suffering stenosis (χ2=9.79, p<0.01), particularly midsegment stenosis (χ2=6.27, p=0.01). REMs were more posterior to the bronchus at the pulmonary hilum than non-REMs (91 % vs. 51 %) (χ2=50.81, p<0.01). CONCLUSIONS: REMs are associated with a lower level, more lateral origin, stenosis and more posterior location with respect to the bronchus at the pulmonary hilum. The unique CTA data obtained in this study showing the anatomy of REMs will be highly useful for surgeons in identifying REMs. KEY POINTS: • Unifocalization is a very important surgical approach for PA-VSD-MAPCA patients. • The anatomical variability of REMs becomes clinically relevant in unifocalization. • CTA provides a non-invasive way to observe the anatomy of REMs. • REMs are associated with lower level, more lateral origin, more midsegment stenosis. • REMs tend to be posterior to the bronchus at the pulmonary hilum.

Fibromuscular Dysplasia of the Coronary Arteries: A Case Report and Review of the Literature.

Fibromuscular dysplasia is a nonatherosclerotic and non-inflammatory vascular disease with primary lesion of renal and internal carotid arteries. We present a neonatal case of fibromuscular dysplasia who died on the second day of life. The newborn suffered from fibromuscular dysplasia of the coronary arteries and a congenital heart defect. The interesting feature of this case was the formation of aneurysms of the coronary arteries with pulmonary atresia. This case demonstrates a casuistically rare form of association between fibromuscular dysplasia of the coronary arteries and pulmonary artery atresia.

Surgical results for pulmonary atresia with intact ventricular septum: a single-centre 15-year experience and medium-term follow-up.

OBJECTIVES: The optimal surgical strategies for pulmonary atresia with intact ventricular septum (PAIVS) are still not well established. This study reviewed our 15-year experience in the management of PAIVS. METHODS: Between July 1999 and June 2014, 170 patients were treated for PAIVS in our heart centre. Based on the morphology of the right ventricle (RV), age and surgical approaches, the patients were divided into two groups: the one-stage surgery group (n = 33) and the staged surgery group (n = 137), in which patients received definitive repair, including biventricular repair, 1.5 ventricular repair and univentricular palliation without or with initial intervention. The median follow-up time was 6.6 years (range: 1-15 years); survival rates, risk factors for death and clinical status after operation were assessed. RESULTS: In the one-stage surgery group, there were three deaths post operation; the estimated 1-, 5- and 15-year survival rates were 97.0, 93.7 and 88.5%, respectively. In the staged surgery group, 23 patients died, including 15 in the waiting period after initial intervention. The estimated 1-, 5- and 15-year survival rates of the staged group were 89.8, 88.2 and 69.1%, without significant difference when compared with the one-stage surgery group (P > 0.05). Independent predictors of mortality were severe RV hypoplasia (P < 0.05) and lower tricuspid valve Z-scores (P < 0.01). At the latest follow-up, most of the patients in both groups had a good clinical status after definitive repair. The re-operation rate was 16.0% (4/25) in the one-stage surgery group compared with 15.4% (6/39) in the staged surgery group. CONCLUSIONS: Both one-stage repair and the staged surgical procedure had acceptable surgical outcomes in this retrospective study. Initial intervention is suitable for neonates or younger patients to promote the growth of the RV, and one-stage definitive repair is a beneficial choice for older patients with PAIVS, in whom the growth potential of the RV is limited.

Ventricular fibrogenesis activity assessed by serum levels of procollagen type III N-terminal amino peptide during the staged Fontan procedure.

OBJECTIVE: We tested the hypotheses that volume overload and cyanosis observed in the pre-Fontan single ventricular circulation are associated with increased ventricular fibrogenesis, that the Fontan procedure helps to reduce fibrogenesis, and that persistently increased fibrogenesis in the Fontan ventricle is associated with ventricular diastolic dysfunction. METHODS: Levels of serum amino-terminal procollagen type III, a marker of tissue fibrogenesis, were measured in 172 patients with single ventricle circulation and 149 controls. Patients were divided into 3 groups according to surgical stage: 59 patients after Blalock-Taussig shunt or pulmonary banding, 60 patients after Glenn surgery (Glenn group), and 53 patients after Fontan surgery (Fontan group). RESULTS: Serum amino-terminal procollagen type III levels were significantly higher among the 3 single ventricle groups than among control patients, but decreased with each surgical stage (0.604, 0.176, 0.143, and 0.073 U/mL, for Blalock-Taussig shunt or pulmonary banding, Glenn, Fontan, and controls, respectively). Severity of volume load and cyanosis were independent determinants of increased amino-terminal procollagen type III levels in patients before Fontan surgery, and persistently increased amino-terminal procollagen type III after Fontan surgery was associated with ventricular diastolic stiffening (r = 0.494, P = .009). Data also indicated close associations between amino-terminal procollagen type III levels and activation of the renin-angiotensin-aldosterone system, suggesting potential involvement of this hormonal system in the increased fibrogenesis after Fontan surgery. CONCLUSIONS: These results suggest that serum amino-terminal procollagen type III may provide important diagnostic information on myocardial fibrosis in patients with single ventricle circulation and raise the possibility that ventricular fibrogenesis may be a potential therapeutic target in this population.

Complete Preoperative Evaluation of Pulmonary Atresia with Ventricular Septal Defect with Multi-Detector Computed Tomography.

OBJECTIVE: To compare multi-detector computed tomography (MDCT) with cardiac catheterization and transthoracic echocardiography (TTE) in comprehensive evaluation of the global cardiovascular anatomy in patients with pulmonary atresia with ventricular septal defect (PA-VSD). METHODS: The clinical and imaging data of 116 patients with PA-VSD confirmed by surgery were reviewed. Using findings at surgery as the reference standard, data from MDCT, TTE and catheterization were reviewed for assessment of native pulmonary vasculature and intracardiac defects. RESULTS: MDCT was more accurate than catheterization and TTE in identification of native pulmonary arteries. MDCT is also the most accurate test for delineation of the major aortopulmonary collateral arteries. The inter-modality agreement for evaluation of overriding aorta and VSD were both excellent. In the subgroup with surgical correlation, excellent agreement was found between TTE and surgery, and substantial agreement was also found at MDCT. CONCLUSION: MDCT can correctly delineate the native pulmonary vasculatures and intracardiac defects and may be a reliable method for noninvasive assessment of global cardiovascular abnormalities in patients with PA-VSD.

CT and MRI of pulmonary valvular abnormalities.

Pulmonary valve disease constitutes a wide spectrum of conditions. Traditionally, echocardiography has been the technique of choice for the evaluation of pulmonary and other valvular disease. However, with advances in technology, computed tomography (CT) and magnetic resonance imaging (MRI) are playing increasingly important roles in the evaluation of these disorders. In this article, we review the normal appearance of the pulmonary valve and then illustrate various variants and pathological entities of the pulmonary valve.

Pulmonary atresia with intact ventricular septum and right ventricular dependent coronary circulation through the "vessels of Wearn".

We present an autopsy case of a male baby born at 35 weeks of gestation with pulmonary atresia with intact ventricular septum (PAIVS), who had coronary blood flow that was dependent on outflow from the right ventricle through the vessels described by Wearn. At 7 weeks of age, he underwent single ventricle palliation consisting of ligation of a patent ductus arteriosus and placement of a modified Blalock-Taussig shunt. The patient experienced a perioperative myocardial infarction, requiring extracorporeal membrane oxygenation. Progressive hemodynamic decline resulted in death 8 days after surgery. Autopsy revealed acute and remote infarctions in both ventricles and fibromuscular dysplasia of the subepicardial and intramural coronary arteries. In 1926, Grant first reported the association between PAIVS and secondary dysplasia of the heart vasculature and hypothesized that the high pressure resulted in dilation of the myocardial sinusoids. Confusion secondary to the unmeritorious dismissal of the myocardial sinusoids has obscured the pathogenesis of PAIVS and led to several publications suggesting second heart field abnormalities as a disease model for PAIVS. We discuss the pathogenesis of PAIVS, the ventriculocoronary arterial connections and the sinusoidal relationship to the vessels described by Wearn, and we attempt to correct the solecism plaguing the nomenclature of myocardial vasculature.

The use of a wire control catheter to treat complex pulmonary artery or vein anatomy.

The difficult performance of certain percutaneous interventions in the field of congenital heart disease is well known. Crossing pulmonary arteries in patients who have previously undergone surgical repair or stenotic pulmonary veins in infants can be typical examples of these technical challenges in the catheterization laboratory. The Venture wire 6 Fr control catheter (St Jude Medical) is compatible with a steerable tapered radiopaque tip that can be manually angulated (up to 90°) by clockwise rotation of a knob located in the proximal handle. This mechanism directs any 0.014″ guidewire and provides back-up support. This catheter has been successfully used in coronary artery intervention for crossing severely tortuous vessels, extreme angulations of side-branch ostia, jailed stents, saphenous vein graft anastomoses, and chronic total occlusions. We report the first use of the Venture wire control catheter (St Jude Medical) in the field of congenital heart disease. Patient #1 was diagnosed with pulmonary atresia and ventricular septal defect and had a proximally migrated stent in the pulmonary trunk and severe left pulmonary artery stenosis. We have used this catheter in order to cross this stent and perform left pulmonary artery stent placement. Patient #2 had postoperative vein restenosis after surgery. The Venture catheter was used to reach the obstructed insertion of the right medium lobe pulmonary vein from a transseptal approach. Techniques from coronary interventional colleagues can help interventional cardiologists in the field of congenital heart disease to treat complex situations.

Surgical management of congenital (non-Ebstein) tricuspid valve regurgitation.

Congenital tricuspid valve regurgitation (TR) is a relatively uncommon condition that includes a heterogeneous group of lesions with a unique management strategy. There are wide anatomic variations that lead to congenital TR in patients without Ebstein malformation. Possible etiologies may include primary valve abnormalities (eg, congenital absence of chordae) or other forms of tricuspid valve dysplasia as in congenitally unguarded tricuspid valve, and patients with pulmonary atresia and intact ventricular septum, which can be similar to Ebstein's valves or secondary regurgitation in association with other anomalies as in atrioventricular septal defects, right ventricular outflow tract obstructive lesions (pulmonary stenosis or atresia with ventricular septal defect [VSD]), tricuspid valve annular dilatation in association with right ventricular volume overload lesions as in congenital coronary arterial fistula with secondary right ventricular enlargement, and Uhl's anomaly. Iatrogenic etiologies in the congenital population include TR secondary to previous VSD closure (chordal or leaflet injury), pacemaker or internal cardiac defibrillator lead-induced TR, and traumatic TR (ruptured chordae). Presentation depends on the severity of the disease and may be apparent in infancy, childhood, or adulthood.

Effect of age on exercise capacity and cardiac reserve in patients with pulmonary atresia with intact ventricular septum after biventricular repair.

OBJECTIVES: In patients with pulmonary atresia with intact ventricular septum (PAIVS), biventricular repair is considered to be the optimal treatment option in the absence of significant right ventricular (RV) hypoplasia. However, long-term clinical outcome studies are limited. We evaluated exercise capacity and cardiac function during pharmacological stress in children and young adults with PAIVS after biventricular repair. METHODS: Ten PAIVS patients after biventricular repair, with a median age of 12 years (range 9-42 years), underwent a cardiopulmonary exercise test, dobutamine stress magnetic resonance imaging (DS-MRI) and delayed contrast enhancement (DCE) MRI. RESULTS: The patients' ages negatively correlated with exercise capacity (r=-0.72, P=0.01) as well as left (LV) and RV stroke volume (SV) response to pharmacological stress (r=-0.72, P=0.02; and r=-0.64, P=0.04; respectively), Furthermore, older age was associated with decreased RV E/A volume ratio and increased pulmonary late diastolic forward flow percentage (r=0-0.65, P=0.04, r=0.66, P=0.03, respectively). RV E/A volume ratio positively correlated with RV-SV response to DS-MRI (r=0.77, P=0.009). and O2-pulse during physical stress correlated with biventricular SV response to DS-MRI. No RV or LV ventricular myocardial fibrosis was detected. CONCLUSIONS: In PAIVS patients after biventricular repair exercise capacity and cardiac reserve decrease with age. These findings appear to be related to impaired diastolic RV function and decreased RV filling, indicating that the function of the relatively small RV deteriorates with time.

[The anatomy features and surgical significance of the pulmonary circuits of pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries].

OBJECTIVES: To analyze the anatomy features of the pulmonary circuits in the patients with pulmonary atresia (PA) with ventricular septal defect (VSD) and major aortopulmonary collateral arteries (MAPCA), and discuss the clinical significance. METHODS: From April 2002 to June 2010, the anatomy features of pulmonary circuits in 33 patients with PA/VSD/MAPCA were examined and analyzed. There were 21 male and 12 female patients. The age ranged from 11 months to 29 years. The anatomic types of PA/VSD included group B for 22 cases, group C for 11 cases. Thirty-one patients of them underwent 33 operative procedures. The operations included aorta-pulmonary shunt in 8 cases, one stage unifocalization with VSD open in 2 cases, complete repair in 23 cases. RESULTS: Twenty-nine (87.9%) patients had native pulmonary arteries, 6 of them were normal size and 23 were hypoplastic size. Four patients (12.1%) had no native pulmonary arteries. The postoperative oxygen saturation of the patients undergone shunt and one stage unifocalization was increased to 83% to 90%. There was one early death after complete repair because of multiorgan function failure. There were 4 cases of severe low cardiac output and 3 cases of respiratory function failure. Sixteen patients after complete repair were followed up more than one year. The postoperative right ventricular pressure was 41 to 99 mmHg (1 mmHg = 0.133 kPa). The ejection fraction value was more than 50% in 14 patients and less than 50% in 2 patients. Two patients had medium pulmonary insufficiency. CONCLUSIONS: An individualized approach based on the anatomy of the pulmonary circuits permits achievement in the patients with PA/VSD/MAPCA. The surgical strategy for PA/VSD/MAPCA mainly depends on the anatomy features of native pulmonary arteries, confluent pulmonary arteries and MAPCA.

Changing trends in the management of pulmonary atresia with intact ventricular septum: the Melbourne experience.

OBJECTIVE: Management of pulmonary atresia with intact ventricular septum (PAIVS) can be directed to either biventricular repair or univentricular palliation. The optimal management strategy has yet to be defined. METHODS: All patients operated at the Royal Children's Hospital, Melbourne for PAIVS between 1990 and 2006 (n = 81) were reviewed. Patients were retrospectively stratified into a simple three-tiered classification based on right ventricle (RV) size. Multivariate logistic regression analysis was performed to identify risk factors of mortality. RESULTS: The distribution of RV sizes was normal in 11 (14%), moderate hypoplasia in 45 (56%), and severe hypoplasia in 25 (31%) patients. RV-to-coronary-artery connections were present in 33 (41%) and RV coronary dependence in six patients (7%). Sixteen patients died (20%). The end-status of the remaining patients was biventricular repair in 31/81 (38%), 1½-ventricle repair in 10/81 (12%), Fontan circulation in 14/81 (17%), transplantation in 1/81 (1%), and still awaiting repair in 9/81 (11%). Ten-year survival was 80% (95% confidence interval (CI): 71-87%). Independent predictors of mortality were lower tricuspid valve (TV) annulus size Z-score and the presence of RV-to-coronary-artery connections. CONCLUSIONS: A simple three-tiered classification based on RV size may allow initial stratification into biventricular or univentricular repair for patients with normal RV size and severe RV hypoplasia. In patients with moderate RV hypoplasia, the presence of RV-to-coronary-artery connections or a TV Z-score<-2 should caution one against attempting biventricular repair.

Tetralogía de Fallot con atresia pulmonar: Morfopatología y anatomía quirúrgica / Tetralogy of Fallot with pulmonary atresia: Morphopathology and surgical anatomy

Se detalla la morfopatología de la tetralogía de Fallot con atresia pulmonar como un espectro de variaciones que sirve de fundamento para destacar la anatomía quirúrgica de esta cardiopatía y se muestra la base embriológica que determina su estructura. Se estudiaron 35 corazones con el sistema secuencial segmentario. Se determinó: situs atrial, conexiones entre los segmentos cardíacos y entre el ventrículo derecho y la vasculatura arterial pulmonar. El situs atrial fue solitus, predominó la conexión atrioventricular concordante (33), las conexiones ventriculoarteriales fueron concordantes (17), doble salida de ventrículo derecho (9) y única vía de salida (9). Todos presentaron atresia valvular pulmonar; el tronco pulmonar fue hipoplásico (20), atrésico proximal (6) y ausente (9), ramas pulmonares confluentes e hipoplásicas (25), ausencia de confluencia (5), ausencia total de ramas y de conductos arteriosos (5) y colaterales aortopulmonares (10). Los corazones mostraron un espectro morfopatológico de severidad que expresa la tendencia a la desaparición de la conexión entre el ventrículo derecho y la circulación arterial intrapulmonar. Se resaltan las formas de la irrigación arterial pulmonar como fundamento para unifocalizar el flujo hacia los pulmones y se hace hincapié en la utilidad de la clasificación anatomoquirúrgica de Barbero Marcial. El conocimiento embriológico es útil para entender las conexiones vasculares del ventrículo derecho con los derivados de los sextos arcos aórticos, los vasos arteriales intrapulmonares y las colaterales aortopulmonares.

The morphopathology of tetralogy of Fallot with pulmonary atresia is detailed as a spectrum of variations which is the foundation to highlight the surgical anatomy of this cardiopathy and it is shown the embryological basis which determines its structure. Thirty five hearts were studied with the methodology of the segmental sequential system. The atrial situs, the connections between the cardiac chambers and between the right ventricle and the arterial pulmonary vasculature were determined. The atrial situs was solitus, the concordant atrioventricular connection was the most frequent (33), the ventriculoarterial connections were concordant (17), double outlet right ventricle (9) and single outlet (9). All hearts had atresia of the pulmonary valve; the pulmonary trunk was hypoplastic (20), atretic proximally (6) and completely absent (9), confluent and hypoplastic pulmonary branches (25), absence of confluence (5), complete absence of pulmonary branches and arterial ducts (5) and presence of aortopulmonary collaterals (10). The hearts show a morphopathologic spectrum of severity which documents the tendency in disappearing the connection between the right ventricle and the intrapulmonary arterial circulation. The determination of the arterial supply to the lungs is highlighted to unifocalize the blood flow toward the lungs. The usefulness of Barbero Marcial's surgical classification is emphasized. The embryologic knowledge is basic in understanding the vascular connections between right ventricle and the derivatives of embryonic sixths aortic arches, the intrapulmonary arterial vessels and the aortopulmonary collaterals.

Surgical strategy for pulmonary atresia with intact ventricular septum: initial management and definitive surgery.

Pulmonary atresia with intact ventricular septum is difficult to manage, and the surgical procedures are associated with high mortality and morbidity. The lesion is morphologically heterogeneous, with varying degrees of right ventricular and tricuspid valve hypoplasia. Aberrations of the coronary circulation are common. A single approach is impractical because the wide spectrum of right heart morphology makes a uniform surgical approach impossible. Anatomical criteria, such as the degree of tricuspid valve or right ventricular hypoplasia or whether a right ventricular infundibulum is present, have been used to assign the infants to single-ventricular or biventricular repair tracks. If the patient is considered a candidate for biventricular repair, right ventricular decompression, either alone or combined with a systemic-pulmonary artery shunt, is performed, whereas only a systemic-pulmonary artery shunt is performed in a candidate for single-ventricular repair. Several authors reported that the Z-value of the tricuspid valve diameter could be a guide to the initial procedure; however, poor interobserver reproducibility and wide normal ranges are serious limitations. Definitive operations, including biventricular repair, one-and-a-half ventricular repair, or Fontan-type operation, are performed to eliminate cyanosis. The most important problem when planning a strategy for a definitive repair is the fact that right ventricular growth and its contribution to pulmonary flow is difficult to predict before the operation. The management protocol should be determined by the precisely estimated morphology of the right ventricle and tricuspid valve, and the adequacy of the protocol should be analyzed based on surgical outcomes.

Is the morphologic mitral valve in discordant atrioventricular connections always normal?

BACKGROUND: The purpose of this study was to determine structural features and variations in the mitral valve guarding inflow of the morphologic left ventricle in hearts with discordant atrioventricular connections. METHODS: Morphologic investigation was carried out on the inlet valve to the morphologic left ventricle in 48 autopsied specimens with this particular entity of malformation. RESULTS: The tension apparatus was straddling to the morphologic right ventricle in 2. Another 34 hearts had a bifoliate valve and the papillary muscles abnormally oriented; a solitary papillary muscle in 3, two papillary muscles but deviated in 5, one of two papillary muscles being dysmorphic in 9, and three or more papillary muscles in 17. The origin of these papillary muscles was frequently deviated. In 5 hearts with a trifoliate or quadrifoliate valve, multiple papillary muscles were also the case. One of these had thick leaflets, a part of which was adherent to a membranous flap around the ventricular septal defect as well as to subpulmonary fibrous tissue tags. Eventually, the valve was comparable with the mitral valve seen in the normally structured heart in only 7 hearts (15%). There was no obvious correlation noted between the presence of abnormality in the mitral valve and that in the tricuspid valve. CONCLUSIONS: Architectural abnormalities are not rare in the morphologic mitral valve in this setting. The valvar structure needs precise recognition.

Exclusion of the non-functioning right ventricle in children with pulmonary atresia and intact ventricular septum.

OBJECTIVE: A group of patients with pulmonary atresia and intact ventricular septum (PAIVS) have to undergo single ventricle repair. In these patients, the presence of the non-functioning right ventricle (RV) may lead to the aggravation of RV to coronary connections and left ventricular (LV) dysfunction. To prevent these deleterious effects, the RV was excluded surgically. METHODS: Between December 2000 and February 2006, 10 patients with PAIVS underwent RV exclusion in conjunction with cavo-pulmonary anastomosis (n=6) or systemic-to-pulmonary artery shunt (n=4). Median age at surgery was 5 months (range, 0.2-13.8). Median z-value of the tricuspid valve was -4.0 (range, -6.5 to -1.3). None had RV dependent coronary circulation. The tricuspid valve was closed directly or using a patch. Thrombotic materials were inserted into the RV cavity in eight patients. RESULTS: There was no mortality. Follow-up was completed in all patients for up to 79.1 months (median, 30.3). Seven patients underwent a Fontan procedure and the other three are waiting. Eight patients showed completely obliterated RV after exclusion. One of the two patients who had residual RV cavity underwent re-exclusion after a Fontan operation. Postoperative echocardiography revealed that LV end-diastolic dimension increased with borderline significance (p=0.050), whereas LV end-systolic dimension showed no significant changes. During follow-up, LV showed no evidence of regional ischemia or global dysfunction, and fractional shortening significantly increased compared with the pre-exclusion value (p=0.017). CONCLUSIONS: This study demonstrates that RV exclusion may be performed safely in a selected group of patients with PAIVS. This procedure may have beneficial effects on LV systolic function, by preventing possible ischemia, and on LV diastolic function, by obliterating the non-functioning cavity and improving the geometry of the ventricular septum.