OPTILOW: A Low-Profile Approach for Implanting Optimus-L Stents in Infants and Children.

Background: Stent implantation poses challenges in small children due to their limited vessel size and rapid growth. This multicenter study evaluates in vivo efficacy of implanting Optimus-L stents in small patients using a low-profile approach.

Methods: We retrospectively reviewed data from children weighing ≤20 kg with congenital heart stenotic lesions who received Optimus-L stents manually mounted on small-sized balloon catheters (diameter ≤12 mm) using a hand-actuated compression tool and implanted through small-sized sheaths (≤8 Fr) at our institutions between May 2022 and January 2024. Stent performance was assessed.

Results: We identified 28 patients (67.8% male) with median age and weight of 3.4 years (interquartile range [IQR], 1.5-5.5) and 12.9 kg (IQR, 9.1-16.4). Six (21.4%) were infants, 11 (39.3%) ≤10 kg. Stenotic lesions included 16 branch pulmonary arteries, 9 aortic isthmus, 2 right ventricular outflow tracts, and 1 Glenn anastomosis. Percentage of stenosis was 50% (IQR, 36%-58%). All implantations were successful without complications. The procedures mostly used 7 Fr sheaths for stents on 6, 7, and 8 mm balloons and 8 Fr sheaths for 9, 10, 12 mm balloons. Median stent expansion percentage was 95% (IQR, 90%-96%). Median vessel diameters increased from 4.6 mm (IQR, 3.8-5.1) to 8.8 mm (IQR, 7.5-9.5) (<0.001), with median stenosis expansion at 103% (IQR, 51%-146%). Median stent shortening was 1.9% (IQR, 0%-3.9%). Two patients required redo stent balloon dilation after 18 and 20 months. Median follow-up was 8 months (IQR, 3.2-13.2). Median last recorded Doppler velocity on implanted stents was 1.6 m/s (IQR, 1.2-2).

Conclusions: Optimus-L stents can safely treat arterial and venous stenosis in infants and small children via a low-profile approach with good outcomes.