Hypoplastic Left Heart Syndrome: Is There a Role for Fetal Therapy?

Figures

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  FIGURE 1. Different phenotypes of left ventricular hypoplasia in the fetus. (A) A four-chamber view of a fetus with 24 weeks and critical aortic stenosis is shown with a severely dilated left ventricle. Panel (B) shows a four-chamber view of a fetus at 27 weeks with a long and skinny, but apex forming left ventricle. LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle.

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  FIGURE 2. Echocardiographic signs of an evolving hypoplastic left heart syndrome. Panel (A) shows a 3-vessel view of a fetus with critical aortic stenosis with antegrade flow in the ductus arteriosus Botalli (red flow) and retrograde flow in the aortic arch (blue flow). In panel (B) left to right shunting at the atrial level of the same fetus is shown (arrow).

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  FIGURE 3. Natural history of a fetus with critical aortic stenosis. The evolution of a hypoplastic left heart syndrome in a fetus with critical aortic stenosis is shown. The fetus was diagnosed at 24 + 1 weeks of gestation with a severely dilated and poorly contracting, but apex forming left ventricle (A). Five weeks later the fetus showed marked signs of left ventricular hypoplasia and severe EFE, the apex being formed by the right ventricle (B). In panel (C), the four-chamber view of the same fetus shows severe left ventricular hypoplasia in terms of a hypoplastic left heart syndrome making a univentricular palliation inevitable. EFE, endocardial fibroelastosis; LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle.

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  FIGURE 4. Technique of fetal aortic valvuloplasty performed under ultrasound guidance. Fetal aortic valvuloplasty of a fetus at 25 weeks of gestation with critical aortic stenosis and eHLHS is shown. In panel (A) the ultrasound guided puncture of the fetal thoracic wall is shown, the arrow marks the needle just before entering the fetus. The needle has been introduced into the left ventricle (B), asterisk marks the needle tip inside the left ventricle. The guidewire and the balloon catheter have crossed the aortic valve in panel (C) and the needle is slightly retracted to allow good positioning of the balloon just before dilation of the aortic valve (**). Panel (D) shows full insufflation of the balloon catheter (**). eHLHS, evolving hypoplastic left heart syndrome; LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle.

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  FIGURE 5. Pulmonary vein Doppler patterns in the hypoplastic left heart with incremental restriction of the interatrial communication. Panel (A) shows a fetus with CAS and an unrestrictive interatrial communication; note that there is reduced flow during atrial systole (A-wave). Panel (B) shows a fetus with HLHS and restrictive, but patent atrial septum. Prominent A-wave flow reversal during atrial systole may be indicative of relevant restriction. Panel (C) shows the pulmonary venous flow pattern in a fetus with HLHS and intact atrial septum. Diastolic pulmonary vein flow is almost missing.

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  FIGURE 6. A fetus at 28 weeks gestation with HLHS and intact atrial septum undergoing FCI. Stenting of the interatrial septum in a fetus with intact atrial septum and HLHS is shown. In panel (A) severely dilated pulmonary veins (arrows) indicate severe left atrial hypertension. The asterisk marks a thickened and into the right atrium bowing atrial septum. In panel (B) severe left atrial hypertension is indicated by severely abnormal pulmonary vein Doppler with almost missing diastolic flow and severe A-wave reversal during atrial systole. The arrow in panel (C) marks the placed atrial septum stent with good flow through the stent indicated by the red color Doppler signal. Note that the pulmonary vein Doppler in panel (D) is almost normalized in the same patient directly after stent placement with good diastolic flow and no presence of A-Wave reversal.