Vascular ring surgery – can we do better?

Background

Vascular anomalies of the Aortic arch can cause respiratory symptoms in children due to tracheal compression. Treatment consists of division of the vascular rings, nevertheless data regarding mid- term results is scarce. The purpose of this study was to evaluate clinical results of vascular ring surgery.

Methods

Between2007–2014, 85 children underwent vascular ring surgery. 51 had Double Aortic Arch (DAA, 60%), 31 Right Arch with Aberrant Subclavian Artery (RAA & ALSA, 36.5%) and 3 had RAA, mirror image branching & left ductus arteriosus (3.5%). Mean age and weight at operation were 12.4±13months and 8.6±4.1 kg respectively. Mid-term follow-up included clinical follow up by a pulmonologist (38 patients, 44.7%) and a telephone questionnaire (71 patients, 83%) performed 57±25.7 months after surgery.

Results

In most patients, symptomatic relief occurred in less than 6 months (table 1). Mid –term follow up revealed that although most parents described a significant improvement in their child's respiratory symptoms (95%), a significant number of patients described some residual respiratory symptoms (table 2). We did not find any significant association between age at surgery (under 6 month), or vascular ring anatomy (DAA vs. RAA&ASA) and the presence of residual symptoms at follow up

Conclusions

Surgical division of vascular rings results in a significant clinical improvement within one year, nevertheless many patients remain symptomatic to some degree. We found no association between the age at surgery or anatomic variant to the presence of symptoms in mid- term follow up. Further evaluation whether a more aggressive surgical approach is warranted in order to decrease the incidence long-term symptoms.

Funding Acknowledgement

Type of funding source: None

Dual targeting of EphA2 and ER restores tamoxifen sensitivity in ER/EphA2-positive breast cancer

Abstract #3020

Background: Overexpression and altered function of EphA2 receptor tyrosine kinase are critical in the progression of breast cancer and provide a novel target for breast cancer therapy. We have previously demonstrated that EphA2 overexpression decreases estrogen dependence and tamoxifen sensitivity both in vitro and in vivo. EA5, a novel monoclonal antibody that mimicks the binding of ephrin A to EphA2, reverses the effect of EphA2 overexpression and restores tamoxifen sensitivity in EphA2-transfected MCF-7 cells (MCF-7EphA2) in vitro. Here we report the impact of EA5 on in vivo tumor growth and its ability to overcome in vivo tamoxifen resistance in MCF-7EphA2 xenografts. Furthermore, we investigated the mechanisms by which EphA2 overexpression decreases the estrogen dependence and contributes to tamoxifen resistance in ER+ breast cancer models.
 Material and Methods: MCF-7 cells transfected with vector (MCF-7neo) or EphA2 (MCF-7EphA2) were implanted in the right and left mammary fat pads of athymic mice. Treatment with EA5 (5 mg/kg/i.p./5 days/week), vehicle, tamoxifen (1 mg/oral gavage/5 days/week), or EA5 and tamoxifen in combination was initiated once tumors were established. To explore the role of EphA2 overexpression on ER-dependent mechanisms, we used two different ER+/EphA2-transfected cell line models (MCF-7neo/ MCF-7EphA2 and T47Dneo/ T47DEphA2). We measured ER activity and expression of ER-dependent proteins in response to 17β-estradiol (E2;10-10 M), 4-hydroxy-tamoxifen (10-6 M, and EA5 antibody (3μg/mL). Interaction of ER and EphA2 was investigated using GST-pulldown and co-immunoprecipitation approaches. Gene array studies suggested that EphA2 may impact ER via noncanonical pathways, leading to an investigation of focal adhesion kinase (FAK) signaling.
 Results: EA5 inhibits primary tumor growth and restores tamoxifen sensitivity in the MCF-7EphA2 in vivo model;EA5 had no impact on in vivo tumor growth in MCF-7neo xenografts. Using T47DEphA2 in vitro model, we verified that EphA2 decreases ER activation in response to E2 stimulation consistent with our earlier results in MCF-7EphA2 model. We found no direct interaction between ER and EphA2 and no difference in expression of canonical ER-dependent proteins, ER coactivators or corepressors. However, E2 stimulation phosphorylates FAKTyr925 in ER+/EphA2+ cell lines but not in ER+/EphA2- cell lines. Treatment of T47DEphA2 cells with EA5 and tamoxifen leads to dephosphorylation of FAKTyr925 in the presence of E2 stimulation.
 Conclusion: Our data demonstrate that dual targeting of EphA2 and ER is a promising approach for delaying resistance to tamoxifen. The data support our hypothesis that EphA2 impacts ER function via a FAK dependent pathway.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3020.

Transcatheter closure of secundum atrial septal defects with the amplatzer septal occluder: early experience

BACKGROUND

Secundum atrial septal defect is a common congenital heart defect that causes right heart volume overload and produces symptoms usually after the third decade of life. Treatment until the last few years has been open heart surgery.

OBJECTIVES

To review our early experience with transcatheter closure of ASD2 using the Amplatzer septal occluder.

METHODS

Between November 1999 and February 2000, 20 children and young adults with a median age of 9.1 years (4.2-35.1 years) were referred for transcatheter closure of ASD2. Diagnosis was established by transthoracic echocardiography. Implantation was performed under general anesthesia through the femoral vein with the guidance of transesophageal echocardiography and fluoroscopy. Femoral arterial puncture was performed for blood pressure monitoring during the procedure. The device size chosen was similar to the balloon-stretched diameter of the ASD2.

RESULTS

Implantation was completed successfully in 18 patients. Two patients were referred for elective surgery: one had an unsuitable anatomy for transcatheter closure by TEE in the catheterization laboratory and the device could not be implanted properly, the other patient had a large multiperforated septal aneurysm that was retrieved. Mean ASD2 diameter by TTE and TEE was similar (13.9 +/- 3 mm, 13.4 +/- 3.5 mm) and mean stretched diameter was 18.3 +/- 4.3 mm. Mean Qp:Qs (pulmonary flow:systemic flow) was 2.2 +/- 0.6. Mean fluoroscopy time for the procedure was 14.8 +/- 4.8 minutes. The patients were discharged the day after the procedure. Four patients had a tiny leak immediately post-procedure, and none had a leak at one month follow-up. The only complication was a small pseudoaneurysm of the femoral artery in one patient, that resolved spontaneously.

CONCLUSIONS

Transcatheter closure of ASD2 with the Amplatzer septal occluder is a safe and effective alternative to surgical closure. Long-term outcome has to be evaluated.

Measurement of endogenous nitric oxide production

The measurement of exhaled pulmonary nitric oxide concentrations requires that contamination from the upper respiratory tract and inhaled gases be eliminated. This can be achieved with no risk in the clinical setting of intubated patients of all ages in the operating room or intensive care unit. Further modifications of the anesthetic/ventilatory circuit allow for accurate determination of tidal volume and minute ventilation.

Balloon angioplasty of postsurgical recoarctation in infants: the risk of restenosis and long-term follow-up

OBJECTIVES

This study was undertaken to evaluate the long-term results of balloon angioplasty (BA) for postsurgical recoarctation in infants.

BACKGROUND

Balloon angioplasty is a well-accepted modality for the treatment of recoarctation. However, infants remain a group of concern because of their size, risk for complications and the potential for restenosis with growth. Age <12 months has been determined to be a risk factor for the development of recoarctation after angioplasty for native coarctation. Although studies on postsurgical coarctation have found no relationship between age at angioplasty and the development of recoarctation, few studies specifically addressing infants have been performed.

METHODS

Clinical, echocardiographic, hemodynamic and angiographic data on 22 consecutive children <1 year of age who underwent BA between 1986 and 1996 were reviewed.

RESULTS

A successful result, defined as a postprocedure gradient of < or =20 mm Hg, was achieved in 20 of 22 (91%) infants with a reduction in the systolic peak pressure gradient from 48 +/- 27 to 9 +/- 10 mm Hg (p < 0.001) and an increase in coarctation diameter from 2.7 +/- 1.1 to 5.2 +/- 1.5 mm (p < 0.001). At long-term follow-up of a median of 56 months (0.6 to 12 years), the restenosis rate after an initial optimal result was 16% (3 of 19). Five (24%) infants required reintervention (2 initially unsuccessful; 3 recoarctation), with a success rate of 95% after two procedures. Suboptimal long-term outcome correlated with a lower infant weight.

CONCLUSIONS

Balloon angioplasty can be safely performed in infants, with good long-term results. The risk of restenosis is low and can be successfully managed with repeat angioplasty.

Inhaled nitric oxide therapy in a critically ill neonate with Ebstein's anomaly

The successful use of nitric oxide (NO) inhalation in a critically ill neonate with Ebstein's anomaly of the tricuspid valve is reported for the first time. This use of inhaled NO therapy suggests a therapeutic intervention that directly addresses the pathophysiologic process of severe neonatal Ebstein's anomaly.

Aortic stenosis and patent ductus arteriosus: pressure gradients pre- and posttranscatheter ductal occlusion

Three patients with patent ductus arteriosus and moderate aortic stenosis had a marked reduction in aortic valve gradient following transcatheter ductal occlusion. The hemodynamic effects of an aortopulmonary shunt on the severity of left ventricular outflow obstruction and the implications on intervention are discussed.

Single coronary artery complicating stent implantation for homograft stenosis in tetralogy of Fallot

Successful stent implantation for conduit stenosis has been described; however, this procedure may be complicated by compression of adjacent structures during expansion. We report on a rare case of a single right coronary artery system complicating stent implantation for relief of homograft stenosis in tetralogy of Fallot.

Kingella kingae endocarditis in a child with hair-cartilage hypoplasia

Abstract. Kingella kingae is a fastidious Gram-negative rod that since the 1980s has been appreciated as a cause of a variety of human infections, including bone and joint infections, bacteremia, and rarely endocarditis [2, 6, 7, 9]. K. kingae endocarditis is rare, and only a few cases occur in normal, native valves. We report a case of K. kingae endocarditis in a patient with hair-cartilage hypoplasia who had previously undergone bone marrow transplantation. The combination of these rare conditions is discussed.

Implantation of balloon-expandable stents for coarctation of the aorta: implantation data and short-term results

We report the immediate results and the short-term follow-up in a group of selected patients with coarctation of the aorta who underwent endovascular stent implantation. Balloon-expandable stents were implanted in 6 patients (mean age 19.8 +/- 5.1 years) with coarctation of the aorta (4 recurrent and 2 native) who underwent a total of 7 procedures (6 implantation and 1 further expansion). The systolic peak pressure gradient was decreased from 36.7 +/- 16.9 to 13.3 +/- 23.2 mm Hg (P < 0.005). There was a 66% increase in the mean coarctation diameter from 9.3 +/- 1.7 to 15.6 +/- 3.1 mm (P = 0.001) with the ratio of the coarctation to descending aorta diameter, measured at the level of the diaphragm, increasing from 0.49 +/- 0.1 to 0.81 +/- 0.2 (P < 0.005). The dilatation was successful in expanding the stent to an acceptable diameter in 5 of 6 patients. One patient underwent successful further expansion of a stent implanted 22 months previously. There were no immediate complications during balloon expansion and stent implantation. One patient suffered a femoral arterial bleed requiring surgical repair. There was one unrelated death. All patients were hypertensive (systolic blood pressure > 140 mm Hg) prior to stent implantation. At mean follow-up of 8 months, 3 patients are normotensive. There was no recurrence of coarctation, aortic dissection, or aneurysm formation in the patients in whom stent implantation was successful. These findings indicate that balloon-expandable stent implantation for coarctation of the aorta in selected patients is a safe and effective alternative approach for relieving the obstruction with a low complication rate and no recoarctation at short-term follow-up.

Cell death signal transduction and Bcl-2 function

The mechanism by which Bcl-2 can insulate cells against multiple diverse apoptotic signals is largely undefined. How is it possible that Bcl-2, which possesses no known catalytic function, can protect against multiple cell-death signals? A proposal to address this question postulates that Bcl-2 functions at convergence points common to most cell-death signal-transduction pathways. This review attempts to integrate observations regarding cell-death signalling in an effort to define points of convergence. The ceramide/ SAPK/JNK and NF kappa B pathways, in particular, were emphasized. Potential points at which Bcl-2 may function frequently involve the transmembrane trafficking of molecules implicated in the mediation of apoptosis. The selectivity of this process and the effector proteins with which Bcl-2 associated remain to be elucidated.

Implantation of balloon-expandable stents for coarctation of the aorta: implantation data and short-term results

We report the immediate results and the short-term follow-up in a group of selected patients with coarctation of the aorta who underwent endovascular stent implantation. Balloon-expandable stents were implanted in 6 patients (mean age 19.8 +/- 5.1 years) with coarctation of the aorta (4 recurrent and 2 native) who underwent a total of 7 procedures (6 implantation and 1 further expansion). The systolic peak pressure gradient was decreased from 36.7 +/- 16.9 to 13.3 +/- 23.2 mm Hg (P < 0.005). There was a 66% increase in the mean coarctation diameter from 9.3 +/- 1.7 to 15.6 +/- 3.1 mm (P = 0.001) with the ratio of the coarctation to descending aorta diameter, measured at the level of the diaphragm, increasing from 0.49 +/- 0.1 to 0.81 +/- 0.2 (P < 0.005). The dilatation was successful in expanding the stent to an acceptable diameter in 5 of 6 patients. One patient underwent successful further expansion of a stent implanted 22 months previously. There were no immediate complications during balloon expansion and stent implantation. One patient suffered a femoral arterial bleed requiring surgical repair. There was one unrelated death. All patients were hypertensive (systolic blood pressure > 140 mm Hg) prior to stent implantation. At mean follow-up of 8 months, 3 patients are normotensive. There was no recurrence of coarctation, aortic dissection, or aneurysm formation in the patients in whom stent implantation was successful. These findings indicate that balloon-expandable stent implantation for coarctation of the aorta in selected patients is a safe and effective alternative approach for relieving the obstruction with a low complication rate and no recoarctation at short-term follow-up.