Conotruncal anomalies in the fetus: Referral patterns and pregnancy outcomes in a dedicated fetal cardiology unit in South India

Abstract

Objective: To describe the referral patterns and pregnancy outcomes of fetuses with conotruncal anomalies (CTA) from a fetal cardiology unit in South India.

Methods: Records of 68 women identified to have diagnosis of CTA on fetal echocardiography (mean gestational age 26.8 ± 5.9 weeks; range 17-38 weeks) during the period 2008-2011 were reviewed.

Results: The most common indication for referral was suspected congenital heart disease during routine antenatal scan (89.7%). The various CTA diagnosed included Tetralogy of Fallot (TOF, 44.1%), Double outlet right ventricle (DORV, 27.9%), Transposition of great vessels (TGA, 8.8%), TOF with pulmonary atresia (TOF-PA, 8.8%), TOF absent pulmonary valve (TOF-APV, 7.4%) and truncus arteriosus (TA, 2.9%). Extra cardiac anomalies were reported in 4 fetuses (7.1%). Pregnancy outcomes included pregnancies not culminating in live-birth (54.4%), delivery at term (41.2%) with 3 patients (4.4%) being lost to follow-up. Proportion of pregnancies not culminating in live-birth lesion wise include: TOF (53.3%), DORV (52.6%), TGA (50%), TOF -APV (80%), TOF-PA (50%), and TA (50%). Twenty-four babies (35.3%) received post-natal cardiac care with 5 (7.4%) undergoing neonatal surgical procedures. Seven babies (10.3%) died in neonatal period, including 2 who underwent surgery. The accuracy of fetal echo was 96.4% for primary lesion and 67.9% for complete segmental diagnosis.

Conclusions: Pre-natal diagnosis of CTA, despite a high diagnostic accuracy, prompted utilization of post-natal tertiary cardiac care in a limited proportion of patients, including those with reparable lesions. Focus in developing countries should shift towards earlier referral, improving awareness about treatment options and a comprehensive evaluation for associated anomalies.

Keywords: Conotruncal anomalies; fetal echocardiography; outcomes.

Figure 1

Types of conotruncal anomalies diagnosed (N = 68); All numbers in percentages. TOF = Tetralogy of Fallot, TOF PA = Tetralogy of Fallot with pulmonary atresia, TOF APV = Tetralogy of Fallot with absent pulmonary valve, DORV = Double outlet right ventricle, TGA = Transposition of great arteries, TA = Truncus Arteriosus

Figure 2

Immediate post-natal outcomes of fetuses delivered alive (N=28) Footnote: NND = neonatal death, *Surgery = included 3 aorto-pulmonary shunts (one TOF and 2 TOF PA), one arterial switch operation (TGA) and one truncus arteriosus repair with conduit