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Coronary sinus atrial septal defects are the rarest defects of the atrial septum comprising

Transcatheter closure of secundum-type atrial septal defects (ASDs) using the AMPLATZER™ Septal Occluder (ASO) has been in use for more than a decade since its US Food and Drug Administration approval in 2001. Device embolization remains an uncommon complication, which can sometimes occur after the initial deployment. Previous reports of ASO devices embolized to the left ventricle have primarily been managed by open-heart surgical retrieval. We present a case of an ASO device embolized to the left ventricular outflow tract (LVOT) 18 hr after initial implantation, which was successfully retrieved percutaneously, followed by successful closure of the ASD using a larger device. © 2014 Wiley Periodicals, Inc.

Renal artery stenosis (RAS) accounts for 10 % of cases of systemic hypertension in children. Initial management involves anti-hypertensive therapy. Percutaneous interventions are documented for the treatment of RAS in the adult population. In children, case reports suggest benefit.This is a retrospective analysis of consecutive patients referred for catheterization for RAS between 2002 and 2010 at a single institution. Recorded variables included: age, weight, systemic blood pressure, minimal luminal diameter, interventional devices, antihypertensive medications, contrast volume, and complications.Twelve patients (median age 8.2, IQR 6-12.4 years); median weight 42.8 kg, IQR: 25-47.4 kg) were referred for renal artery catheterization and underwent percutaneous intervention. Overall, minimal luminal diameter (MLD) increased by 1.2 ± 0.9 mm for all patients (p 0.05) and by 1.3 ± 0.9 mm for post-renal transplant patients (p 0.05). Only stent angioplasty patients demonstrated significant improved blood pressure (p 0.05). One patient had stent thrombosis requiring re-intervention with repeat balloon angioplasty.This retrospective analysis suggests that percutaneous intervention might play a role in the management of RAS, with an improvement in MLD in children with RAS. Transcatheter intervention is technically feasible with low morbidity. A prospective, longitudinal study is warranted to compare standard medical therapy with percutaneous interventions.

A 7-month-old patient in congestive heart failure due to a moderate sized patent ductus arteriosus (PDA) underwent uncomplicated implantation of an Amplatzer Ductal Occluder (ADO1). Two months after percutaneous device PDA closure, left pulmonary artery (LPA) stenosis was discovered. Rather than spontaneous improvement as reported in previous cases, our patient's LPA stenosis progressed in severity 7 months after ADO1 placement. A catheterization demonstrated a 32 mm Hg peak gradient from her main pulmonary artery to her LPA. She underwent successful stent angioplasty of her LPA with an excellent result and preserved PDA closure. This case demonstrates that stent angioplasty is a feasible an effective method of relieving LPA obstruction caused by a PDA occluder device. Additionally, despite slight deflection by the stent, the ADO1 device continued to provide complete ductal closure. Stent angioplasty should be considered in patients who have LPA stenosis caused by ADO1 occluder device that does not improve over time. © 2013 Wiley Periodicals, Inc.

Transcaval access enables delivery of large-caliber devices to the aorta in patients with small or diseased iliofemoral arteries [(1,2)][1]. The technique has been described in detail elsewhere [(3)][2] and requires pre-procedural computed tomography planning to identify a calcium-free 7.6 mm × 9.

Purpose: To develop an active delivery system that enhances visualization of nitinol cardiac occluder devices during deployment under real-time magnetic resonance imaging (MRI). Materials and Methods: We constructed an active delivery cable incorporating a loopless antenna and a custom titanium microscrew to secure the occluder devices. The delivery cable was tuned and matched to 50Ω at 64 MHz with the occluder device attached. We used real-time balanced steady state free precession in a wide-bore 1.5T scanner. Device-related images were reconstructed separately and combined with surface-coil images. The delivery cable was tested in vitro in a phantom and in vivo in swine using a variety of nitinol cardiac occluder devices. Results: In vitro, the active delivery cable provided little signal when the occluder device was detached and maximal signal with the device attached. In vivo, signal from the active delivery cable enabled clear visualization of occluder device during positioning and deployment. Device release resulted in decreased signal from the active cable. Postmortem examination confirmed proper device placement. Conclusion: The active delivery cable enhanced the MRI depiction of nitinol cardiac occluder devices during positioning and deployment, both in conventional and novel applications. We expect enhanced visibility to contribute to the effectiveness and safety of new and emerging MRI-guided treatments. J. Magn. Reson. Imaging 2012;36:972–978. © 2012 Wiley Periodicals, Inc.

Objectives This study sought to evaluate feasibility of nonsurgical transthoracic catheter-based left ventricular (LV) access and closure. Background Implanting large devices, such as mitral or aortic valve prostheses, into the heart requires surgical exposure and repair. Reliable percutaneous direct transthoracic LV access and closure would allow new nonsurgical therapeutic procedures. Methods Percutaneous direct LV access was performed in 19 swine using real-time magnetic resonance imaging (MRI) and an “active” MRI needle antenna to deliver an 18-F introducer sheath. The LV access ports were closed percutaneously using a commercial ventricular septal defect occluder and an “active” MRI delivery cable for enhanced visibility. We used “permissive pericardial tamponade” (temporary fluid instillation to separate the 2 pericardial layers) to avoid pericardial entrapment by the epicardial disk. Techniques were developed in 8 animals, and 11 more were followed up to 3 months by MRI and histopathology. Results Imaging guidance allowed 18-F sheath access and closure with appropriate positioning of the occluder inside the transmyocardial tunnel. Of the survival cohort, immediate hemostasis was achieved in 8 of 11 patients. Failure modes included pericardial entrapment by the epicardial occluder disk (n = 2) and a true-apex entry site that prevented hemostatic apposition of the endocardial disk (n = 1). Reactive pericardial effusion (192 ± 118 ml) accumulated 5 ± 1 days after the procedure, requiring 1-time drainage. At 3 months, LV function was preserved, and the device was endothelialized. Conclusions Direct percutaneous LV access and closure is feasible using real-time MRI. A commercial occluder achieved hemostasis without evident deleterious effects on the LV. Having established the concept, further clinical development of this approach appears realistic.

Objectives The aim of this study was to close ventricular septal defects (VSDs) directly through the chest wall using magnetic resonance imaging (MRI) guidance, without cardiopulmonary bypass, sternotomy, or radiation exposure. Background Surgical, percutaneous, and hybrid management of VSD each have limitations and known morbidity. Methods Percutaneous muscular VSDs were created in 10 naive Yorkshire swine using a transjugular laser catheter. Under real-time MRI guidance, a direct transthoracic vascular access sheath was introduced through the chest into the heart along a trajectory suitable for VSD access and closure. Through this transthoracic sheath, muscular VSDs were occluded using a commercial nitinol device. Finally, the right ventricular free wall was closed using a commercial collagen plug intended for arterial closure. Results Anterior, posterior, and mid-muscular VSDs (6.8 ± 1.8 mm) were created. VSDs were closed successfully in all animals. The transthoracic access sheath was displaced in 2, both fatal. Thereafter, we tested an intracameral retention sheath to prevent this complication. Right ventricular access ports were closed successfully in all, and after as many as 30 days, healed successfully. Conclusions Real-time MRI guidance allowed closed-chest transthoracic perventricular muscular VSD closure in a clinically meaningful animal model. Once applied to patients, this approach may avoid traditional surgical, percutaneous, or open-chest transcatheter (“hybrid”) risks.

Objectives We hypothesized that X-ray fused with magnetic resonance imaging (XFM) roadmaps might permit direct antegrade crossing and delivery of a ventricular septal defect (VSD) closure device and thereby reduce procedure time and radiation exposure. Background Percutaneous device closure of membranous VSD is cumbersome and time-consuming. The procedure requires crossing the defect retrograde, snaring and exteriorizing a guidewire to form an arteriovenous loop, then delivering antegrade a sheath and closure device. Methods Magnetic resonance imaging roadmaps of cardiac structures were obtained from miniature swine with spontaneous VSD and registered with live X-ray using external fiducial markers. We compared antegrade XFM-guided VSD crossing with conventional retrograde X-ray–guided crossing for repair. Results Antegrade XFM crossing was successful in all animals. Compared with retrograde X-ray, antegrade XFM was associated with shorter time to crossing (167 ± 103 s vs. 284 ± 61 s; p = 0.025), shorter time to sheath delivery (71 ± 32 s vs. 366 ± 145 s; p = 0.001), shorter fluoroscopy time (158 ± 95 s vs. 390 ± 137 s; p = 0.003), and reduced radiation dose–area product (2,394 ± 1,522 mG·m2 vs. 4,865 ± 1,759 mG·m2; p = 0.016). Conclusions XFM facilitates antegrade access to membranous VSD from the right ventricle in swine. The simplified procedure is faster and reduces radiation exposure compared with the conventional retrograde approach.

An arterial switch is the corrective procedure of choice for d-transposition of the great arteries but may be associated with increased morbidity and mortality when performed in low-birth-weight infants. Conversely, delaying surgery often leads to left ventricular "deconditioning" as pulmonary arteriolar resistance decreases. We present an infant with a birth weight of 940 g with d-transposition of the great arteries with an intact ventricular septum whose bilateral pulmonary artery branch stenosis allowed for maintenance of near systemic left ventricular pressure, thereby protecting against deconditioning. This case also represents the smallest reported patient to undergo a successful balloon atrial septostomy.

Although rare, a congenital direct fistula connection between the proximal right pulmonary artery and the left atrium can present as cyanosis in the newborn. We report the first case in which catheter-based coil closure of such a fistula in a neonate resulted in rapid clinical improvement, obviating the need for surgical repair.