Echocardiographic versus Angiographic Measurement of the Patent Ductus Arteriosus in Extremely Low Birth Weight Infants and the Utility of Echo Guidance for Transcatheter Closure

Background: Transthoracic echocardiography (TTE) is increasingly utilized for guiding transcatheter closure of patent ductus arteriosus (PDA) in extremely low birth weight (ELBW) infants. The objectives of this study were to compare PDA size measurements by TTE with angiographic measurements and to describe TTE techniques used in guiding transcatheter PDA closure (TCPC) in ELBW infants.

Methods: One hundred twenty-five consecutive ELBW infants (gestational age < 27 weeks, birth weight < 1 kg) who underwent TCPC before 8 weeks of age under TTE guidance were included. Patent ductus arteriosus sizes were measured from the procedural TTE and angiograms retrospectively by blinded observers. The TTE PDA diameters at the aortic (ED1) and pulmonary end (ED2) were compared with the corresponding angiographic diameters (CD1 and CD2). The TTE PDA lengths, obtained by two techniques (EL1, a straight line between ED1 and ED2; and EL2, a curvilinear line along the PDA), were compared with the PDA length by angiography (CL). Transthoracic echocardiography was used to guide accurate device positioning within the PDA.

Results: The procedure weight was 600-1,460 g. The TTE and angiographic PDA diameters were comparable (mean ED1 vs CD1 = 4.5 ± 0.68 vs 4.4 ± 0.85 mm, P = .26; and mean ED2 vs CD2 = 3.1 ± 0.72 vs 3.2 ± 0.94 mm, P = .14). The angiographic length was underestimated by EL1 by 2.6 ± 1.6 mm (P < .0001), while EL2 estimated it better (mean EL2 vs CL = 11.0 ± 1.83 vs 10.8 ± 2.15 mm; P = .40). Transcatheter PDA closure was successful in 100% of the cases using TTE guidance. There were no intraprocedural complications.

Conclusions: Transthoracic echocardiography guidance during TCPC in ELBW infants eliminates the need for aortograms via femoral arterial access, preventing the complications associated with it. Transthoracic echocardiography PDA measurements are comparable to angiographic measurements, thereby assisting in appropriate device size selection.