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

Long-term experience with the one-and-a-half ventricle repair for simple and complex congenital heart defects

OBJECTIVES

The one-and-a-half ventricle repair (1.5VR) is a surgical alternative to Fontan circulation or high-risk biventricular repair in patients with complex congenital heart disease (CHD) with a hypoplastic right ventricle (RV). We report our 25 years of experience to evaluate whether the degree of anatomical complexity of the CHD can affect long-term outcomes.

METHODS

This is a retrospective study including patients undergoing 1.5VR between 1994 and 2018. Clinical records and operative reports were reviewed. Follow-up data were collected from all survivors at the last evaluation or by phone contact.

RESULTS

Twenty-nine patients underwent 1.5VR [median age: 3.5 years, interquartile range (IQR) 0.8-7.8]. Fifteen patients had 'simple' (i.e. confined to right heart lesions) anatomical characteristics (48.3%); the median tricuspid valve annulus z-score was -3.5 (IQR -6.2 to +3.6). There were no operative deaths. The median hospital stay was 21 days (IQR 10-33), with postoperative complications in 21 patients (75.8%). At a median follow-up of 13.2 years (IQR 3.2-25.6 years; completeness 96.6%), there were 3 late deaths. There was no significant difference in survival and in freedom from adverse events between simple and complex anatomy groups. However, stress test findings showed a tendency towards a higher maximum oxygen uptake in the simple group (P = 0.055).

CONCLUSIONS

The 1.5VR strategy is an effective low-risk surgical option for patients with CHD with hypoplastic RV. When it is planned from birth, late outcomes can be satisfactory. In our experience, the presence of associated major cardiac anomalies was not associated with either worse early or long-term outcomes and functional status.

Echocardiographic parameters associated with biventricular circulation and right ventricular growth following right ventricular decompression in patients with pulmonary atresia and intact ventricular septum: Results from a multicenter study

BACKGROUND

In patients with pulmonary atresia, intact ventricular septum (PA/IVS) following right ventricular (RV) decompression, RV size and morphology drive clinical outcome. Our objectives were to (1) identify baseline and postdecompression echocardiographic parameters associated with 2V circulation, (2) identify echocardiographic parameters associated with RV growth and (3) describe changes in measures of RV size and changes in RV loading conditions.

METHODS

We performed a retrospective analysis of patients who underwent RV decompression for PA/IVS at four centers. We analyzed echocardiograms at baseline, postdecompression, and at follow up (closest to 1-year or prior to Glenn circulation).

RESULTS

Eighty-one patients were included. At last follow-up, 70 (86%) patients had 2V circulations, 7 (9%) had 1.5 ventricle circulations, and 4 (5%) had single ventricle circulations. Follow-up echocardiograms were available in 43 (53%) patients. The majority of patients had improved RV systolic function, less tricuspid regurgitation (TR), and more left-to-right atrial shunting at a median of 350 days after decompression. Multivariable analysis demonstrated that larger baseline tricuspid valve (TV) z-score (P = .017), ≥ moderate baseline TR (P = .045) and smaller baseline RV area (P < .001) were associated with larger increases in RV area. Baseline RV area ≥6 cm² /m² had 93% sensitivity and 80% specificity for identifying patients who ultimately achieved 2V circulation. All patients with RV area ≥8 cm² /m² at follow up achieved 2V circulation. This finding was confirmed in a validation cohort from a separate center (N = 25). Factors associated with achieving RV area ≥8 cm² /m² included larger TV z-score (P = .004), ≥ moderate baseline TR (P = .031), and ≥ moderate postdecompression pulmonary regurgitation (P = .002).

CONCLUSIONS

Patients with PA/IVS and smaller TV annuli are at risk for poor RV growth. Volume-loading conditions signal increased capacity for growth sufficient for 2V circulation.

Efficacy of Bosentan in patients after Fontan procedures: a double-blind, randomized controlled trial

Fontan surgery is a widely used palliative procedure that significantly improves the survival period of patients with complex congenital heart disease (CHD). However, it does not decrease postoperative complication rate. Previous studies suggested that elevated mean pulmonary artery pressure (mPAP) and vascular resistance lead to decreased exercise tolerance and myocardial dysfunction. Therapy with endothelial receptor antagonists (Bosentan) has been demonstrated to improve the patients' prognosis. A double-blind, randomized controlled trial was performed to explore the efficacy of Bosentan in treating patients who underwent the Fontan procedure. Eligible participants were randomly divided into Bosentan group and control group. Liver function was tested at a local hospital and the results were reported to the phone inspector every month. If the results suggested abnormal liver function, treatment would be adjusted or terminated. All the participants finished the follow-up study, with no patients lost to follow-up. Unblinding after 2-year follow-up, no mortality was observed in either group. However, secondary end-points were found to be significantly different in the comparable groups. The cardiac function and 6-min walking distance in the Bosentan group were significantly superior to those in the control group (P=0.018 and P=0.027). Bosentan could improve New York Heart Association (NYHA) functional status and improve the results of the 6-min walking test (6MWT) in Fontan patients post-surgery, and no other benefits were observed. Furthermore, a primary meta-analysis study systematically reviewed all the similar clinical trails worldwide and concluded an overall NYHA class improvement in Fontan patients who received Bosentan treatments.