Does a bidirectional Glenn shunt improve the oxygenation of right ventricle–dependent coronary circulation in pulmonary atresia with intact ventricular septum?

Prenatal echocardiographic classification and prognostic evaluation strategy in fetal pulmonary atresia with intact ventricular septum

Fetal pulmonary atresia with intact ventricular septum (PA/IVS) is a rare congenital heart disease. The present study aimed to classify PA/IVS and determine the relationship between prenatal echocardiographic characteristics and postnatal biventricular or univentricular repair strategies.A total of 51 fetuses with PA/IVS were examined from 2012 to 2019. Data on prenatal echocardiography, associated anomaly, karyotype, and outcome were collected. Two-dimensional measurements included tricuspid valve (TV) z-score, mitral valve (MV) z-score, TV/MV ratio, and ratio of right to left ventricle (RV/LV) length, whereas color Doppler measurements included degree of tricuspid regurgitation (TR), ventriculo-coronary artery communication (VCAC), tricuspid inflow duration (TID), cardiac cycle duration (CCD), middle cerebral artery pulsatility index (MCA PI), and umbilical artery pulsatility index (UA PI). Diagnostic classification was based on the development of RV and the presence or absence of VCAC. Postnatal evaluation was divided according biventricular or univentricular repair.Of the 51 fetuses with PA/IVS, 20 were type I, 17 were type II, and 14 were type III. Only one fetus exhibited right aortic arch. The karyotype of all the fetuses was normal. Of the 28 patients who underwent postnatal surgery, 13 (46%) underwent biventricular repair and 15 (54%) underwent univentricular repair. TV z-score was significantly higher for the biventricular repair group compared with univentricular repair group (-1.20 ± 0.98 vs -4.33 ± 0.80, P = .000). TV/MV, RV/LV length, and TID/CCD were significantly higher for the biventricular repair group than the univentricular repair group (0.81 ± 0.14 vs 0.54 ± 0.09, 0.71 ± 0.11 vs 0.49 ± 0.09, 39.20 ± 3.84 vs 29.16 ± 4.58, P = .000). Moderate or severe TR and VCAC were significantly different between the 2 groups (P = .000). Gestational age, MCA PI, and UA PI did not differ between the 2 groups (P = .72, P = .36, P = .06). The cutoff values for the biventricular repair characteristic curves were TV z-score >-3.28, TV/MV ratio >0.71, RV/LV length >0.62, and TID/CCD >33.95%. The sensitivities of the TV z-score, TV/MV, RV/LV length, and TID/CCD were 100%, 77%, 85%, and 92%, respectively. The specificities of the TV z-score, TV/MV, RV/LV length, and TID/CCD were 94%, 100%, 100%, and 94%, respectively.Fetal echocardiography was able to classify PA/IVS according to variable degree of RV and VCAC. In fetal PA/IVS, TV z-score >-3.28, TV/MV >0.71, RV/LV length >0.62, TID/CCD >33.95%, moderate and severe TR, and the absence of VCAC were associated with postnatal biventricular repair strategy. These findings may have implications for prenatal counseling and prediction of fetal outcome.

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.