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We report our experience with transcatheter patent ductus arteriosus (PDA) closure in premature infants and compare patients grouped by the device used for closure: the Microvascular Plug, “MVP” (Medtronic, Minneapolis, MN); Micro Plug Set, “Micro Plug” (KA Medical, Minneapolis, MN); and Amplatzer Piccolo Occluder, “Piccolo” (Abbot, Santa Clara, CA). We also report trends in device selection over time. Studies examining outcomes according to device selection for PDA closure in premature infants are lacking. We performed a retrospective review of all percutaneous PDA closures in premature infants at a single center (June 2018–May 2021). Patients were grouped by initial device selected for PDA closure (intention to treat). Institutional Review Board approval was obtained. 58 premature infants [MVP (n = 25), Micro Plug (n = 25), and Piccolo (n = 8)] underwent successful transcatheter PDA closure (mean gestational age 27 weeks 2 days; mean weight at procedure 1.4 kg; mean age at procedure 28 days). Pre-procedural demographics, procedural data, and follow-up data were similar between groups. There were no significant procedural adverse events. Three devices (2 MVP, 0 Micro Plug, 1 Piccolo p = 0.27) embolized after the procedure. One other device was removed for concern for aortic obstruction. Device selection evolved with a clear trend toward the Micro Plug device over time. Demographic, procedural, and follow-up data were similar between the MVP, Micro Plug, and Piccolo groups. The Micro Plug did not require exchange for suboptimal fitting or embolize and became our preferred device in most cases.

Urbanisation and habitat loss are major threats to wildlife populations globally. Understanding how species respond to anthropogenic changes is therefore crucial to mitigating threats and developing conservation management strategies. We examined the habitat use of five fishing cats (Prionailurus viverrinus) in Sri Lanka’s capital city, Colombo, a densely urbanised landscape with a mosaic of wetland habitats, cultivated areas, and altered open spaces. We investigated: (1) to what extent all five cats used human-impacted versus natural wetland habitat; (2) whether there were behavioural shifts to avoid human activity throughout the diel cycle; (3) the home range sizes of two resident females and one resident male, and the extent of the area used by the two translocated males; (4) whether the two translocated males would survive introduction to a new urban environment. We monitored the fishing cats for 637 days (mean = 127) and collected a total of 2278 GPS (5-h interval) collar locations. We found that all five individuals used highly urbanised areas more than we expected. Home range sizes of the three residents were smaller than fishing cat home ranges in less disturbed landscapes. Though our sample size was small, our findings suggest that fishing cats use urbanised areas in Colombo, particularly at night, likely to avoid daytime human activity. Further comprehensive ecological study is needed to explore the aspects of fishing cat ecology that facilitate their persistence, and aid in their conservation across increasingly urbanised areas.

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.

Transcatheter valve interventions require careful planning and rely heavily on multimodality imaging. In contrast to echocardiography and computed tomography cardiovascular magnetic resonance (CMR) remains underused in clinical practice. CMR techniques such as multiplanar cine imaging unlimited by echo windows or ionizing radiation exposure, quantification of flow, and advanced tissue characterization have the potential to add valuable complimentary information to the evaluation of patients with valvular heart disease. In this paper, we review the evidence for CMR to guide transcatheter valve interventions with a focus on practical applications for the interventionist.

BACKGROUND: Cardiac magnetic resonance (MR) imaging is a valuable tool in congenital heart disease; however patients frequently have metal devices in the chest from the treatment of their disease that complicate imaging. Methods are needed to improve imaging around metal implants near the heart. Basic sequence parameter manipulations have the potential to minimize artifact while limiting effects on image resolution and quality. OBJECTIVE: Our objective was to design cine and static cardiac imaging sequences to minimize metal artifact while maintaining image quality. MATERIALS AND METHODS: Using systematic variation of standard imaging parameters on a fluid-filled phantom containing commonly used metal cardiac devices, we developed optimized sequences for steady-state free precession (SSFP), gradient recalled echo (GRE) cine imaging, and turbo spin-echo (TSE) black-blood imaging. We imaged 17 consecutive patients undergoing routine cardiac MR with 25 metal implants of various origins using both standard and optimized imaging protocols for a given slice position. We rated images for quality and metal artifact size by measuring metal artifact in two orthogonal planes within the image. RESULTS: All metal artifacts were reduced with optimized imaging. The average metal artifact reduction for the optimized SSFP cine was 1.5+/−1.8 mm, and for the optimized GRE cine the reduction was 4.6+/−4.5 mm (P

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.

Background Conductive guidewires and intravascular catheters are at risk of RF-induced heating under MRI [1]. Heating is found predominantly at the tip of conductive wires [2], and is modulated by wire diameter, length and insulation thickness [3]. Non-conductive materials, such as polymer, impart unsatisfactory mechanical properties on guidewires in terms of flexibility, stiffness, and torquability, for navigating tortuous cardiovascular structures and for safely delivering catheter devices.

Background Realtime MR enables radiation free guidance for right heart catheterization (RHC). In addition to catheter navigation for sampling of invasive pressures and blood oxygen saturations, MR permits concomitant assessment of cardiac chamber volumes and cardiac output with phase contrast flow measurements. By performing repeat measurements under different physiological provocations (e.g. saline volume challenge, inhaled nitric oxide, or exercise), diagnostic yield increases by revealing symptoms and pathologic findings not apparent at rest. Herein we present the NIH experience of MR RHC to date.

A 12-year-old male presented with a 6-week history of apparent digital vasculitis with color changes of the distal fingers and erythematous macules of the palms and soles. Physical examination revealed skin findings of Carney complex and an abnormal cardiac examination. Echocardiography demonstrated a large left atrial mass, which caused partial obstruction during diastole and moderate mitral valve insufficiency. Surgical excision and pathological examination of the mass confirmed the presence of a large, peduculated myxoma. This case illustrates the presentation of Carney complex with left atrial myxoma as apparent vasculitis and Raynaud's phenomenon.

Background Invasive right heart catheterization plays a central role in the investigation of patients with cardiac and pulmonary vascular disease. Physiological provocations during invasive heart catheterization augment the diagnostic yield and can provide useful prognostic information. MRI catheterization combines invasive hemodynamic measurements with MRI structural and functional evaluations thus providing superior diagnostic information than either test alone. An additional benefit to both patient and operator is no ionizing radiation, which is of particular value in pediatric patients.

Background We have begun to perform routine and research MRI right heart catheterization in adults and research MRI catheterization in children. We report our technologist workflow. Methods Scanner preparation: The scanner facade and bore are covered with adhesive clear sterile drapes and surface coils enveloped in sterile plastic bags. A MR catheterization pack contains only non-ferromagnetic supplies. Sterile

Background Visualizing blood flow is important in MR-guided interventions (e.g. repairing structural heart defects). We introduce a method, called Virtual Dye Angiography (VDA), to visualize flow in a manner inspired by contrast-enhanced X-ray angiography. Slightly similar to arterial spin labeling, VDA saturates a localized region using multidimensional RF pulses. Unlike phase-contrast velocity mapping, which has unsuitably long acquisition times, VDA can be integrated into existing highcontrast, high-SNR SSFP imaging sequences with minimal modification.