<p><strong>INTRODUCTION: </strong>While frequently performed in the adult population, percutaneous coronary artery stent angioplasty (CSA) in infants is rare. CSA in infants is challenging because of limited options in terms of appropriately sized (length and diameter) stents, concern about stenting vessels with significant growth potential and limited data regarding durability of benefit. We report a multicenter case series of infants who underwent CSA.</p>

<p><strong>METHODS: </strong>A multicenter, retrospective case series of infants who underwent percutaneous CSA to treat post-operative coronary artery stenoses was performed.</p>

<p><strong>RESULTS: </strong>Six infants from 3 institutions who underwent post-operative CSA were identified. The anatomic diagnoses were d-transposition of the great arteries in 3 cases, anomalous left coronary artery from the pulmonary artery in 2 and supravalvar aortic stenosis in 1. All infants were critically ill at the time of CSA. Diameters of coronary artery stents used ranged from 2.25 to 2.75 mm. There were no procedural complications. All stents were patent immediately after placement and the clinical condition improved or stabilized in all patients. Follow-up angiography was available for 3 patients at 4 to 16 months post-CSA, at which time 67% (2/3) remained patent.</p>

<p><strong>CONCLUSION: </strong>CSA is a feasible and effective therapy for critically ill infants with post-surgical coronary obstruction. Treatment appears to allow at least short-term reperfusion to facilitate recovery of ventricular function and potential development of collateral circulation when longer-term stent patency is not achieved. Longer-term stent patency and coronary artery health remain unanswered questions.</p>

<p><strong>INTRODUCTION: </strong>Balloon and stent angioplasty of the pulmonary arteries (PAs) are frequently performed following superior cavopulmonary connection (SCPC), not only to normalize the caliber of the affected PA but also in hopes of maximizing downstream growth over time. There are limited data on the impact on subsequent PA growth prior to total cavopulmonary connection (TCPC).</p>

<p><strong>METHODS: </strong>A single-center, retrospective cohort study was performed on children who underwent transcatheter (TC) PA intervention following SCPC between January 1, 2010, and December 31, 2018. Growth of treated and contralateral PAs was measured at the lobar bifurcation (distal branch PA [DBPA]) and in the proximal lower lobe (lower lobe branch [LLB]) on serial angiograms. Growth rate was evaluated using a mixed-effect model clustered by individual patient with an interaction term for treated PA and time to evaluate for differential growth rates between treated and contralateral PAs.</p>

<p><strong>RESULTS: </strong>Thirty-five patients underwent TC PA intervention following SCPC, at a median of 70 days (interquartile range: 19-297 days) postoperatively. Significant growth was seen at both DBPA and LLB for raw (0.8 mm/year, 95% CI: 0.6-1.0, &lt; .001 for both) and body surface area (BSA) adjusted measures (8.4mm/m/year, 95% CI: 5.6-11.2, &lt; .001; 7.9 mm/m/year, 95% CI: 5.5-10.2, &lt; .001). The growth rate of the treated vessel was not significantly different from that of the contralateral vessel at the DBPA or LLB positions for raw ( = .71, .70) or BSA-adjusted measurements ( = .86, .64).</p>

<p><strong>CONCLUSION: </strong>Transcatheter PA intervention was associated with normal distal PA growth rate relative to the untreated side.</p>