Page 48 - Journal of Structural Heart Disease Volume 5, Issue 4

Meeting Abstracts
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relief of right ventricular outflow tract (RVOT) obstruction and pulmonary regurgitation (PR) with high rates of proce- dural success, few procedural complications, and improved quality of life. Some patients subsequently require RVOT reintervention, often for recurrent obstruction associ- ated with stent fracture (SF) or endocarditis This analysis evaluates the technical/procedural factors and outcomes following post-TPVR transcatheter RVOT reinterventions, with the primary objective of characterizing the acute and time-related function of the second Melody valve or re-ex- panded original TPV.
Methods: All patients who underwent TPVR with a Melody valve as part of three Medtronic-sponsored prospective multicenter studies were included. Transcatheter rein- terventions included balloon dilation of the previously implanted Melody valve, placement of a bare metal stent within the implanted TPV, or placement of a new TPV in the RVOT (TPV-in-TPV). Indications for reintervention, deci- sions to reintervene, and the method of reintervention were at the discretion of the implanting physician.
Results: A total of 309 patients underwent TPVR in three prospective Melody valve trials and were discharged from the implant hospitalization with a Melody valve in place. Patients were followed for a median of 5.1 (min-max: 0.2- 9.3) years. Transcatheter reintervention on the TPV was per- formed in 46 patients, who are the focus of this report. The first transcatheter reintervention consisted of TPV-in-TPV in 28/46 patients (median 6.9 years [0.4-8.8] after TPVR), simple balloon dilation of the implanted Melody valve in 17/46 (median 4.9 years [2.5-9.3] years after TPVR), and bare metal stent placement alone in 1/46 (4.4 years after TPVR). Indications for the first reintervention included ste- nosis associated with Melody valve SF in 27 patients, ste- nosis without documented SF in 12, and endocarditis with TPV dysfunction in 7 (2 with and 5 without SF). Patients were followed for a median of 3.4 years (0-7.9 years) after the initial reintervention, during which 19 patients under- went another RVOT reintervention. Overall, 5-year freedom from explant and from any later RVOT reintervention after the first reintervention were 85% and 69%, respectively. Notably, freedom from repeat RVOT reintervention was longer in patients undergoing TPV-in-TPV than balloon dilation (78%vs 38% at 5 years, p=0.01).
Conclusions: TPV-in-TPV can be an effective and durable treatment for Melody valve dysfunction. Although balloon dilation of the Melody valve was also acutely effective at reducing RVOT obstruction, the durability of this therapy was limited in this cohort compared to TPV-in-TPV.
61. BRANCH PULMONARY ARTERY REHABILITATION USING DRUG ELUTING STENTS: EARLY RESULTS
Daniel Duarte, Patcharapong Suntharos, Lourdes Prieto
Nicklaus Children's Hospital, Miami, USA
Background: Patients with congenital or post-operative pulmonary artery stenosis and small pulmonary arteries often require multiple catheterizations for pulmonary artery rehabilitation. Frequently, balloon angioplasty results in only temporary improvement. Conventional pre-mounted stents are easier to advance given the lower profile, how- ever the smaller sizes are limited in their post-dilation potential to keep up with vessel growth. Additionally, in-stent restenosis is common in very small stents. Drug- eluting stents (DES) are pre-mounted stents that can be deployed in smaller vessels, theoretically reduce the rate of in-stent restenosis, and can be fractured longitudinally to potentially insert a larger size stent. We report the early results of DES for pulmonary artery stenosis in infants and small children.
Methods: We performed a retrospective chart review from 5/2018-4/2019 of all patients who had implantation of a DES in a stenotic pulmonary artery at Nicklaus Children’s Hospital. Patient age, weight, reference vessel diame- ter, stenosis diameter and % stenosis pre and post stent implantation, and complications were recorded. In patients who had follow up catheterizations degree of in-stent rest- enosis was assessed, and stent diameter was measured to evaluate for recoil.
Results: A total 9 patients underwent placement of 20 DES over 13 different procedures at a mean age of 23 months (1-98 months), and weight of 10.4 Kg (3.8-25.5Kg). All stents were Resolute Onyx (Medtronic, Santa Rosa, CA). The most common diagnosis was tetralogy of Fallot with pul- monary atresia and aortopulmonary collaterals (67%). The mean reference vessel diameter was 4.4mm (2.9-4.6mm) with a mean stenosis diameter of 2.2mm (range 0.6- 3.1mm). Implanted stent diameters were 4 mm in six, 4.5 mm in two, and 5 mm in nine vessels. Following stenting, there was a mean 221% (146 -750%) increase in the mini- mal vessel diameter to 4mm (1.8-5.2mm). Four stents were post-dilated with higher pressure balloons. Post dilation of one stent resulted in lengthening of the stent with increase in the distance between struts, and no further improve- ment of the stenosis than accomplished immediately post stent implantation (81% pre to 56% post). There were no complications. Follow up catheterizations were performed in 4/9 (44%) patients at a mean of 3 months (1-4 months), and none showed in-stent restenosis or stent fractures.
Journal of Structural Heart Disease, August 2019
Volume 5, Issue 4:75-205