Page 30 - Journal of Structural Heart Disease Volume 4, Issue 2

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Case Report
the learning curve associated with RVOT stenting in LBW infants.
Case Presentation
Case 1
An ex-36-week male infant weighing 1.9 kg was di- agnosed soon after birth with ToF. There was failure to pass meconium, and a diagnosis of Hirschsprungs disease required a defunctioning colostomy. Due to progressive cyanosis, the infant was taken to the cath- eter laboratory in the second week of life and under- went RVOT stenting with a 4 × 12-mm coronary stent (Boston Scienti c, Marlborough, MA, USA). There was severe RVOT narrowing (Figure 1) that was crossed with a 0.014” BMW wire (Abbot Vascular, Clonmel, Ire- land) through a 4-F angled Terumo catheter (Terumo Europe NV, Leuven, Belgium) positioned in the RVOT. Further angiography was possible through a Tuo- hy-Borst placed on the catheter over the wire. Stent position was con rmed with the use of transthoracic echocardiography (TTE). The infant tolerated the pro- cedure well with no hemodynamic instability follow- ing placement of the coronary wire in the distal right pulmonary artery. Oxygen saturation improved from mid-70% to mid-90%. The infant required further di- lation of the stent at 3 months with a 6 × 20-mm bal- loon (Boston Scienti c, Marlborough, MA, USA) and underwent uncomplicated complete surgical repair at 6 months.
Case 2
An ex-30 + 3-week male infant with a birth weight of 1.18 kg and an antenatal diagnosis of ToF became progressively cyanosed over the rst 4 weeks of life. Despite administration of oxygen and propranolol for hypercyanotic spells, the patient remained symp- tomatic and was listed for urgent RVOT stenting at 4 weeks of age weighing 1.6 kg. The RVOT was crossed with a 0.014” BMW wire, and a 4 × 12-mm coronary stent was placed across the RVOT. Repeat angiogra- phy suggested residual infundibular muscle proximal to the RVOT stent. With advancement of a second stent, the initial stent milked distally into the main pulmonary artery. It was not possible to advance the second stent into a suitable position, and on remov- al through the sheath, the stent embolized o the
balloon into the right atrium. The stent was retrieved with an Amplatz goose neck snare (Covidien, Plym- outh, MN, USA) and removed. Subsequently, a third 4 × 12-mm stent was advanced to the RVOT, covering the infundibular muscle, and was successful in alle- viating the obstruction. The patient recovered well from the procedure without any sequelae.
At 8 weeks of age, weighing 2.2 kg, the patient re-presented with hypercyanotic spells, and echo- cardiography suggested muscle beneath the previ- ously placed stents. Initial angiography con rmed the wedge of muscle. The stents were crossed with a 0.014” GrandSlam wire (Asahi Intecc, Osaka, Japan) and a 5 × 12-mm Formula 414 stent (Cook Medical, Bloomington, IN, USA) was placed in a good position. Final angiography and echocardiography suggested that the residual muscle bundle was fully covered by the stent.
Further subsequent desaturations led to a right modi ed BTT shunt at 10 weeks of age and subse- quent complete repair at 26 weeks, weighing 5.3 kg.
Case 3
An ex-35 + 4 week male infant with a birth weight of 1.52 kg was diagnosed with ToF with severe RVOT obstruction following birth and was commenced on propranolol and prostaglandin. Clinical features were suggestive of Cornelia de Lange syndrome. At day 21 of life, weighing 1.84 kg, the patient developed progressive cyanosis despite prostaglandin thera- py with a TTE, con rming progressive restriction of the ductus arteriosus. Following a multi-disciplinary team discussion, he was brought to the cardiac cath- eterization laboratory at 23 days of age for an urgent RVOT stent. The RVOT was crossed with a 0.018” Ter- umo wire through a 4-F non-tapered angled Terumo catheter. The Terumo wire was exchanged for a 0.014” GrandSlam wire, which led to signi cant hypotension thought to be secondary to splinting of the tricuspid valve. Some improvement was seen with the admin- istration of adrenaline and withdrawal of the 4-F cath- eter. A 4.5 × 13-mm coronary stent was deployed un- der TTE guidance across the RVOT. This stent migrated proximally with balloon withdrawal, and attempts to manipulate it back into position with a balloon were unsuccessful. A further 4.5 × 18-mm coronary stent was advanced to stabilize the rst stent; however,
Linnane N. et al.
RVOT Stenting in Small Infants