Classification scheme for ductal morphology in cyanotic patients with ductal dependent pulmonary blood flow and association with outcomes of patent ductus arteriosus stenting.

OBJECTIVES: To devise a classification scheme for ductal morphology in patients with ductal dependent pulmonary blood flow (PBF) that can be used to assess outcomes. BACKGROUND: The impact of ductal morphology on outcomes following patent ductus arteriosus (PDA) stenting is not well defined. METHODS: Patients <1 year of age who underwent PDA stenting for ductal dependent PBF at the four centers comprising the Congenital Catheterization Research Collaborative (CCRC) were included. A classification scheme for PDA morphology was devised based on a tortuosity index (TI)-Type I (straight), Type II (one turn), and Type III (multiple turns). A subtype classification was used based upon the ductal origin. RESULTS: One hundred and five patients underwent PDA stenting. TI was Type I in 58, Type II in 24, and Type III in 23 PDAs, respectively. There was a significant association between ductal origin and vascular access site (p < 0.001). Procedure times and need for >1 stent did not differ based on TI. Greater TI was associated with pulmonary artery (PA) jailing (p = 0.003). Twelve (11.4%) patients underwent unplanned reintervention, more commonly with greater TI (p = 0.022) and PA jailing (p < 0.001). At the time of subsequent surgical repair/palliative staging, PA arterioplasty was performed in 32 patients, more commonly when a PA was jailed (p = 0.048). PA jailing did not affect PA size at follow up. CONCLUSIONS: The proposed qualitative and quantitative PDA morphology classification scheme may be helpful in anticipating outcomes in patients with ductal dependent PBF undergoing PDA stenting.

Comparison Between Patent Ductus Arteriosus Stent and Modified Blalock-Taussig Shunt as Palliation for Infants With Ductal-Dependent Pulmonary Blood Flow: Insights From the Congenital Catheterization Research Collaborative.

BACKGROUND: Infants with ductal-dependent pulmonary blood flow may undergo palliation with either a patent ductus arteriosus (PDA) stent or a modified Blalock-Taussig (BT) shunt. A balanced multicenter comparison of these 2 approaches is lacking. METHODS: Infants with ductal-dependent pulmonary blood flow palliated with either a PDA stent or a BT shunt from January 2008 to November 2015 were reviewed from the 4 member centers of the Congenital Catheterization Research Collaborative. Outcomes were compared by use of propensity score adjustment to account for baseline differences between groups. RESULTS: One hundred six patients with a PDA stent and 251 patients with a BT shunt were included. The groups differed in underlying anatomy (expected 2-ventricle circulation in 60% of PDA stents versus 45% of BT shunts; P=0.001) and presence of antegrade pulmonary blood flow (61% of PDA stents versus 38% of BT shunts; P<0.001). After propensity score adjustment, there was no difference in the hazard of the primary composite outcome of death or unplanned reintervention to treat cyanosis (hazard ratio, 0.8; 95% confidence interval [CI], 0.52-1.23; P=0.31). Other reinterventions were more common in the PDA stent group (hazard ratio, 29.8; 95% CI, 9.8-91.1; P<0.001). However, the PDA stent group had a lower adjusted intensive care unit length of stay (5.3 days [95% CI, 4.2-6.7] versus 9.19 days [95% CI, 7.9-10.6]; P<0.001), a lower risk of diuretic use at discharge (odds ratio, 0.4; 95% CI, 0.25-0.64; P<0.001) and procedural complications (odds ratio, 0.4; 95% CI, 0.2-0.77; P=0.006), and larger (152 mm2/m2 [95% CI, 132-176] versus 125 mm2/m2 [95% CI, 113-138]; P=0.029) and more symmetrical (symmetry index, 0.84 [95% CI, 0.8-0.89] versus 0.77 [95% CI, 0.75-0.8]; P=0.008] pulmonary arteries at the time of subsequent surgical repair or last follow-up. CONCLUSIONS: In this multicenter comparison of palliative PDA stent and BT shunt for infants with ductal-dependent pulmonary blood flow adjusted for differences in patient factors, there was no difference in the primary end point, death or unplanned reintervention to treat cyanosis. However, other markers of morbidity and pulmonary artery size favored the PDA stent group, supporting PDA stent as a reasonable alternative to BT shunt in select patients.

Acute and Midterm Outcomes of Transcatheter Pulmonary Valve Replacement for Treatment of Dysfunctional Left Ventricular Outflow Tract Conduits in Patients With Aortopulmonary Transposition and a Systemic Right Ventricle.

BACKGROUND: Transcatheter pulmonary valve replacement (TPVR) is an established therapy for dysfunctional right ventricular (RV) outflow tract conduits. TPVR in patients with congenitally corrected transposition of the great arteries, subpulmonary left ventricle, and left ventricular outflow tract (LVOT) conduit dysfunction has not been studied. Unique anatomic and physiological aspects of this population may contribute to distinct risks and outcomes. METHODS AND RESULTS: Across 10 US centers, 27 patients with a dysfunctional LVOT conduit were evaluated in the catheterization laboratory between December 2008 and August 2015 with the intent to perform TPVR. TPVR was successful in 23 patients (85%). Five serious adverse events occurred in 4 cases (15%), including pulmonary hemorrhage, hypotension requiring vasoactive support, conduit disruption requiring covered stent (n=2), and acute RV dysfunction with flash pulmonary edema. After TPVR, the LVOT peak systolic ejection gradient decreased from median of 35 to 17 mm Hg (P<0.001); pulmonary insufficiency was trivial/none in all but 1 patient, where it was mild. Worsening of systemic RV dysfunction or tricuspid regurgitation was seen in 12 patients (57%) and was associated with a significantly lower post-TPVR LVOT peak systolic ejection gradient (median 17 versus 21 mm Hg; P=0.02) and higher post-TPVR RV sphericity index (median 0.88 versus 0.52; P=0.004). Post-TPVR, there were 2 late deaths because of RV failure and 1 cardiac transplantation because of progressive RV dysfunction and tricuspid regurgitation. CONCLUSIONS: TPVR in dysfunctional LVOT conduits is feasible but associated with an important rate of TPV nonimplantation and procedural serious adverse events. Worsening systemic RV function and tricuspid regurgitation may develop after LVOT TPVR.