Transcatheter pulmonary valve replacement after arterial switch operation.

BACKGROUND: Patients with d-transposition of the great arteries (d-TGA) who have undergone an arterial switch operation (ASO) can develop right ventricular outflow tract (RVOT) dysfunction with pulmonary regurgitation (PR) or stenosis. In these patients, treatment may include transcatheter pulmonary valve replacement (TPVR). Coronary compression is a contraindication occurring in 5% of typical TPVR cases. After ASO, there are various anatomical considerations that can confound TPVR, including potential coronary artery compression. Our goal is to understand feasibility of TPVR in patients following ASO. METHODS: This was a retrospective multicenter cohort study of patients with RVOT dysfunction after ASO who underwent cardiac catheterization with intention to perform TPVR from 2008 to 2020. RESULTS: Across nine centers, 33 patients met inclusion criteria. TPVR was successful in 22 patients (66%), 19 receiving a Melody valve and 3 a SAPIEN valve. RVOT stenosis in isolation or with PR dictated need for TPVR in nearly all patients. One serious adverse event occurred with valve embolization. After TPVR, the RVOT peak gradient decreased from 43 to 9 mm Hg (p < 0.001); PR was trivial/none in all but one patient, in whom it was mild. Coronary compression prohibiting TPVR occurred in eight patients (24%) and two patients (6%) had severe aortic regurgitation from aortic root deformation precluding TPVR. Seven patients underwent RVOT reintervention with a median of 5.3 years post-TPVR. CONCLUSIONS: TPVR in patients with d-TGA after ASO is feasible, but in this cohort, coronary compression or aortic root distortion precluded TPVR in one-third of patients. The rate of RVOT reintervention after TPVR was higher in this cohort of ASO patients that in prior studies.

Total Transcatheter Stage 1: A Word of Caution.

For patients with single ventricle physiology, being able to initially establish systemic blood flow and control pulmonary blood flow is critical to their long-term health. Recently, there have been descriptions in achieving this by a purely transcatheter approach with stenting of the ductus arteriosus and implanting pulmonary flow restrictors, a very appealing prospect. We review a case series of 6 patients who underwent a percutaneous modified stage 1 approach using modified Microvascular plugs (MVP) at our center between September 2019 and December 2019. The initial procedure was technically successful in all patients with single-stage ductal stenting and placement of bilateral modified MVP via femoral access. Four patients underwent repeat cardiac catheterization prior to subsequent surgery that demonstrated elevated Qp:Qs (> 2:1) in 3 of the 4 patients with an elevated mean distal PA pressure > 20 mmHg in all patients. In some patients, the device migrated into the distal right pulmonary artery. One patient after Glenn shunt was found to have significant LPA stenosis requiring stenting. While the percutaneous modified stage 1 approach is a promising approach, we offer a word of caution against widespread adoption of this technique with the currently available devices.

Procedural, pregnancy, and short-term outcomes after fetal aortic valvuloplasty.

OBJECTIVES: We aimed to evaluate the effect of technical aspects of fetal aortic valvuloplasty (FAV) on procedural risks and pregnancy outcomes. BACKGROUND: FAV is performed in cases of severe mid-gestation aortic stenosis with the goal of preventing hypoplastic left heart syndrome (HLHS). METHODS: The International Fetal Cardiac Intervention Registry was queried for fetuses who underwent FAV from 2002 to 2018, excluding one high-volume center. RESULTS: The 108 fetuses had an attempted cardiac puncture (mean gestational age [GA] 26.1 ± 3.3 weeks). 83.3% of attempted interventions were technically successful (increased forward flow/new aortic insufficiency). The interventional cannula was larger than 19 g in 70.4%. More than one cardiac puncture was performed in 25.0%. Intraprocedural complications occurred in 48.1%, including bradycardia (34.1%), pericardial (22.2%) or pleural effusion (2.7%) requiring drainage, and balloon rupture (5.6%). Death within 48 hr occurred in 16.7% of fetuses. Of the 81 patients born alive, 59 were discharged home, 34 of whom had biventricular circulation. More than one cardiac puncture was associated with higher complication rates (p < .001). Larger cannula size was associated with higher pericardial effusion rates (p = .044). On multivariate analysis, technical success (odds ratio [OR] = 10.9, 95% confidence interval [CI] = 2.2-53.5, p = .003) and later GA at intervention (OR = 1.5, 95% CI = 1.2-1.9, p = .002) were associated with increased odds of live birth. CONCLUSIONS: FAV is an often successful but high-risk procedure. Multiple cardiac punctures are associated with increased complication and fetal mortality rates. Later GA at intervention and technical success were independently associated with increased odds of live birth. However, performing the procedure later in gestation may miss the window to prevent progression to HLHS.

MRI Catheterization: Ready for Broad Adoption.

In recent years, interventional cardiac magnetic resonance imaging (iCMR) has evolved from attractive theory to clinical routine at several centers. Real-time cardiac magnetic resonance imaging (CMR fluoroscopy) adds value by combining soft-tissue visualization, concurrent hemodynamic measurement, and freedom from radiation. Clinical iCMR applications are expanding because of advances in catheter devices and imaging. In the near future, iCMR promises novel procedures otherwise unsafe under standalone X-Ray guidance.

Patent Ductus Arteriosus Stenting for All Ductal-Dependent Cyanotic Infants: Waning Use of Blalock-Taussig Shunts.

[Figure: see text].

Aortic Root Thrombosis on ECMO-A Novel Management Strategy.

A 15-year-old presented in cardiogenic shock secondary to viral myocarditis requiring venoarterial extracorporeal membrane oxygenation (ECMO) support. He developed large thrombi of the left ventricle and aortic root. Anticoagulation was increased, and medications were initiated to decrease the likelihood of aortic valve opening. He underwent balloon atrial septostomy followed by placement of a left atrial vent. A pigtail catheter was placed in the ascending aorta for direct heparin infusion. Serial echocardiograms showed progressive resolution of the thrombi. He was successfully weaned from ECMO and discharged home without neurological deficits.

Ontogeny of VEGF, IGF-I, and GH in neonatal rat serum, vitreous fluid, and retina from birth to weaning.

PURPOSE: Vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF)-I, and growth hormone (GH) are major regulators of physical growth, as well as normal and pathologic retinal development. Ocular tissues are protected by the blood-ocular barrier. This study was conducted to test the hypothesis that the ontogenic profiles of VEGF, IGF-I, and GH in the rat serum, vitreous fluid, and retina are compartment specific, and that the vitreous is a reservoir for retinal growth factors. METHODS: Sprague-Dawley rat pups were killed at birth (postnatal day [P]0) and at P7, P14, and P21. At death, serum, vitreous fluid, and retinal homogenates were analyzed for ontogeny of VEGF, IGF-I, and GH. RESULTS: VEGF levels were 10 times higher in the vitreous than in serum at all stages of development. Vitreous and serum VEGF levels progressively declined, with lowest concentrations at P21. Retinal VEGF levels increased with the highest concentration at P21. IGF-I levels in the vitreous decreased from P7 through P21. IGF-I levels in serum and retinal homogenates increased with advancing postnatal age. Although IGF-I levels were four times higher in the vitreous than in the retina at P0, equilibration was achieved at P21. GH levels in the vitreous were 10 times lower than serum levels, were decreased at P14 and P21, and remained unchanged from P0 through P21 in the retina. CONCLUSIONS: VEGF and IGF-I act in concert to promote retinal development with the vitreous fluid as a reservoir. The ontogenic profiles of VEGF, IGF-I and GH in the serum and ocular compartments are specific. These differences should be considered when therapies for ROP are proposed.

Comparative effects of early postnatal ibuprofen and indomethacin on VEGF, IGF-I, and GH during rat ocular development.

PURPOSE: Ibuprofen and indomethacin are nonselective prostaglandin synthetase inhibitors that have been shown to improve oxygen-induced retinopathy in mice. Vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF)-I, and growth hormone (GH) are potent growth factors involved in retinal development. This study was conducted to examine and compare the effects of early postnatal ibuprofen and indomethacin on ocular and systemic VEGF, IGF-I, and GH during rat ocular development. METHODS: Newborn rats were treated with intraperitoneal injections of low and high doses of ibuprofen or indomethacin at birth (postnatal day [P]1) and on P2 and P3. A control group received equivalent volumes of saline. At P14, vitreous fluid, retinal homogenates, and serum were analyzed for VEGF, IGF-I, and GH protein levels. Retinal mRNA expression of VEGF splice variants (VEGF188, VEGF164, VEGF120), VEGF receptors (VEGFR-1, VEGFR-2, Npn-1, Npn-2), and pigment epithelium-derived factor (PEDF) were also examined. RESULTS: Animals treated with high-dose ibuprofen had significantly lower somatic growth and higher serum and vitreous IGF-I levels. High-dose ibuprofen decreased retinal VEGF levels and retinal VEGF164, VEGF120, and VEGFR-2 transcripts, resulting in a significant increase in the cecal period in 87% of rats at P14. Both indomethacin doses suppressed retinal VEGF164 transcripts without affecting VEGF receptors. CONCLUSIONS: Ibuprofen may be more effective than indomethacin for suppression of retinal VEGF signaling, suggesting a possible therapy for retinal neovascularization. However, deficits in somatic growth concurrent with higher systemic IGF-I levels suggests decreased IGF-I bioactivity. These adverse effects should be considered.

Vaginal versus oral indomethacin in a rabbit model for non-infection-mediated preterm birth: an alternate tocolytic approach.

OBJECTIVE: We examined the hypotheses that vaginal indomethacin is more effective for prolonging gestation, and mediates its tocolytic actions via changes in cervical matrix metalloproteinase (MMP) activity, compared to oral. STUDY DESIGN: Pregnant rabbits induced with mifepristone received oral or vaginal indomethacin; or oral or vaginal vehicle once daily for 2 days. Premature delivery, fetal ductus arteriosus, and cervical MMP activity were assessed. RESULTS: Vaginal indomethacin delayed delivery >72 hours in 100% of the rabbits, extending gestation to 28.2 +/- 0.5 (P < .01) versus 26.4 +/- 0.3, 25.8 +/- 0.5, and 26.5 +/- 0.3 days, for vaginal placebo, oral indomethacin, and oral vehicle, respectively. Fetal ductus arteriosus was patent in all groups. Vaginal indomethacin decreased MMP-1, -8, and -9 activities and increased TIMP-1 levels in the cervix. CONCLUSION: Vaginal indomethacin is more effective than oral for prolonging gestation in the rabbit. Its tocolytic effects may be mediated, in part, by alterations in cervical MMP activity.