86 - Cardiovascular Outcomes following Transcatheter Patent Ductus Arteriosus Closure in Preterm Infants Weighing ≤1500g: Initial Experience from a Canadian Program

Poster Number: 86
Publication Number: 86.2244

Background: Transcatheter PDA closure (TCPC) in preterm infants has emerged as an alternative to surgical ligation. The Hospital for Sick Children established a TCPC program with defined referral criteria and care pathways in 2019 (Figure 1). The program accepts referrals from 3 tertiary neonatal units across the greater Toronto area.

Objective: To describe our experience of TCPC in preterm infants ≤1500g at our centre.

Design/Methods: A single centre retrospective review of premature infants weighing ≤ 1500g who were referred to the TCPC program between 2019 and 2022. Immediate and post-discharge outcomes following referral were identified.

Results: The cohort consisted of 65 neonates born between 22.1 and 27.1 weeks gestation. A device was successfully placed in 54 patients (Figure 2). The mean age and weight at the time of the procedure was 30.2 ± 1.8 days (range 26.6 to 35.6 days) and 1111g ± 193 g (768g to 1500g). Those weighing ≤ 1000g accounted for 46.3% (N =25). There was a trend in referrals for TCPC occurring at a younger postnatal age (39.7 days vs 34 days, p = 0.06) and earlier corrected gestational age (30.6 weeks vs 29.2 weeks, p = 0.03) in the second half of the study period.

Implant success was achieved in 98% of cases (N = 53/54) (Figure 2). Choice of device was the Amplatzer Piccolo Occluder device (Abbott) in 96.3% (N = 52) of cases. Venous access was used to place the device in 100% of cases. There was no early mortality.

Qualitative left ventricular systolic dysfunction occurred in 39% and 29% at 2-4 hours and 24 hours after TCPC with moderate or severe dysfunction in 13% & 11% cases respectively. Milrinone was required in 25.4% infants (N=16/63) for echo dysfunction and/or clinical instability. There was no significant difference in inotrope use between those infants who had TCPC and ligation (12/54 vs 4/9, p 0.22). Ventricular function had recovered in all cases within a week.

100% of patients were followed for 6 months, 60% (N = 38) for 1 year. Major adverse events requiring intervention occurred in 5.5% (N = 3) during follow-up. No patients had a residual shunt. Moderate / severe tricuspid valve regurgitation occurred in 7.4% (N = 4). 9.2% (N = 5) had occlusive venous thrombus. There were 4 non-procedure related late deaths in the cohort and no late reports of infective endocarditis.

Conclusion(s): TCPC is a safe alternative to surgical PDA ligation in preterm infants < 1500g. Acute left ventricular dysfunction occurs commonly in the first 24 hours but resolves quickly. Adverse events requiring intervention are rare.