Automated catheter tip repositioning for intra-cardiac echocardiography.

PURPOSE: Intra-Cardiac Echocardiography (ICE) is a powerful imaging modality for guiding cardiac electrophysiology and structural heart interventions. ICE provides real-time observation of anatomy and devices, while enabling direct monitoring of potential complications. In single operator settings, the physician needs to switch back-and-forth between the ICE catheter and therapy device, making continuous ICE support impossible. Two operator setups are sometimes implemented, but increase procedural costs and room occupation. METHODS: ICE catheter robotic control system is developed with automated catheter tip repositioning (i.e., view recovery) method, which can reproduce important views previously navigated to and saved by the user. The performance of the proposed method is demonstrated and evaluated in a combination of heart phantom and animal experiments. RESULTS: Automated ICE view recovery achieved catheter tip position accuracy of [Formula: see text] mm and catheter image orientation accuracy of [Formula: see text] in animal studies, and [Formula: see text]mm and [Formula: see text] in heart phantom studies, respectively. Our proposed method is also successfully used during transseptal puncture in animals without complications, showing the possibility for fluoro-less transseptal puncture with ICE catheter robot. CONCLUSION: Robotic ICE imaging has the potential to provide precise and reproducible anatomical views, which can reduce overall execution time, labor burden of procedures, and X-ray usage for a range of cardiac procedures.

Functionalization of endovascular devices with superparamagnetic iron oxide nanoparticles for interventional cardiovascular magnetic resonance imaging.

Presently, cardiovascular interventions such as stent deployment and balloon angioplasty are performed under x-ray guidance. However, x-ray fluoroscopy has poor soft tissue contrast and is limited by imaging in a single plane, resulting in imprecise navigation of endovascular instruments. Moreover, x-ray fluoroscopy exposes patients to ionizing radiation and iodinated contrast agents. Magnetic resonance imaging (MRI) is a safe and enabling modality for cardiovascular interventions. Interventional cardiovascular MR (iCMR) is a promising approach that is in stark contrast with x-ray fluoroscopy, offering high-resolution anatomic and physiologic information and imaging in multiple planes for enhanced navigational accuracy of catheter-based devices, all in an environment free of radiation and its deleterious effects. While iCMR has immense potential, its translation into the clinical arena is hindered by the limited availability of MRI-visible catheters, wire guides, angioplasty balloons, and stents. Herein, we aimed to create application-specific, devices suitable for iCMR, and demonstrate the potential of iCMR by performing cardiovascular catheterization procedures using these devices. Tools, including catheters, wire guides, stents, and angioplasty balloons, for endovascular interventions were functionalized with a polymer coating consisting of poly(lactide-co-glycolide) (PLGA) and superparamagnetic iron oxide (SPIO) nanoparticles, followed by endovascular deployment in the pig. Findings from this study highlight the ability to image and properly navigate SPIO-functionalized devices, enabling interventions such as successful stent deployment under MRI guidance. This study demonstrates proof-of-concept for rapid prototyping of iCMR-specific endovascular interventional devices that can take advantage of the capabilities of iCMR.

Building an Adult Congenital Heart Program: Critical Components and Important Allies.

PURPOSE OF THE REVIEW: The purpose of this review is to illustrate specific challenges and opportunities in the building of an adult congenital heart disease (ACHD) program and to highlight critical components and important allies. RECENT FINDINGS: With more than 1.4 million adults with congenital heart disease in the USA alone, access to specialized, compassionate, high-quality comprehensive care requires a shift toward more aggressive expansion of ACHD care, especially in the context of sparse ACHD provider representation in the vast majority of adult medical centers. The effective build of an ACHD program requires measured escalation in management of ACHD complexity matched with cultivation of key resources and clinical services ranging from congenital cardiac surgery and interventional cardiology to acquired heart disease as well as partnerships with non-cardiac specialists. By reframing ACHD care as a shared goal between patients, providers, hospitals, pharmaceutical and device industry, and payers, a potent business model can be built around the developing ACHD program to facilitate acquisition of these key resources.

Transcatheter closure of a sinus venosus atrial septal defect using 3D printing and image fusion guidance.

A 63-year-old man with cirrhosis, hepatocellular carcinoma, and coagulopathy was diagnosed with a sinus venosus atrial septal defect (ASD) and partial anomalous pulmonary venous return (PAPVR) of the right upper pulmonary vein (RUPV). Transcatheter repair by positioning a stent graft in the superior vena cava was planned. Based on three-dimensional (3D) reconstruction of gated cardiac CTA, a 28 mm × 7 cm Endurant II® aortic extension stent graft (Medtronic, MN) was chosen. A 3D model printed from the CTA was used to simulate device deployment, demonstrating successful exclusion of the sinus venosus ASD with return of the RUPV to the left atrium (LA). Post simulation, the 3D model was used for informed consent. The patient was then taken to the hybrid operating room. On-table cone beam CT was performed and registered with the CTA images. This enabled overlay of 3D regions of interest to live 2D fluoroscopy. The stent graft was then deployed using 3D regions of interest for guidance. Hemodynamics and angiography demonstrated successful exclusion of the sinus venosus ASD and unobstructed return of RUPV to the LA. This is the first report of comprehensive use of contemporary imaging for planning, simulation, patient consent, and procedural guidance for patient-centered complex structural intervention in repair of sinus venosus ASD with PAPVR. We propose this as a process model for continued innovation in structural interventions.

Intraoperative cone beam computed tomography-guided endovascular recanalization of an interrupted aorta.

A 42-year-old man sustained a stroke secondary to malignant hypertension and was found to have complete aortic interruption. We report a case of real-time image-guided endovascular repair to highlight the value of preprocedural planning and intraprocedural cone beam computed tomography. Two-dimensional fluoroscopy enhanced with three-dimensional landmarks from cone beam computed tomography was used to direct a Nykanen radiofrequency wire (Baylis Medical, Montreal, Quebec, Canada) through the interruption, avoiding critical adjacent structures. A covered Cheatham-Platinum stent (NuMED, Inc, Hopkinton, NY) was deployed successfully, recanalizing the thoracic aorta. The pressure gradient normalized, and the patient was discharged on postoperative day 1. At 10-month follow-up, the patient was on an antihypertensive regimen of two minimum-dose drugs.

Adult congenital heart disease: magnitude of the problem.

PURPOSE OF REVIEW: To define the magnitude of problems faced by patients with adult congenital heart disease (ACHD) and to identify unmet needs for this population. RECENT FINDINGS: The ACHD population is estimated to include more than 1 million people in the United States and continues to grow at a steady rate. Owing to the decline in early mortality in this group, modern medicine is now faced by the long-term complications associated with congenital heart disease such as chronic heart failure, increased endocarditis risk, elevated burden of arrhythmias, pulmonary hypertension, valvular dysfunction, and pregnancy. SUMMARY: Increasing access to ACHD care, evolution of imaging techniques and transcatheter technology and continued efforts at quality improvement will be key to successfully facing the challenges that are a product of the astounding success of pediatric cardiac surgery.

Transcatheter ventricular septal defect (VSD) creation for restrictive VSD in double-outlet right ventricle.

BACKGROUND: Double-outlet right ventricle (DORV) with a restrictive ventricular septum is a rare but highly morbid phenomenon that can be complicated by progressive left ventricular hypertrophy, arrhythmias, aneurysm formation, severe pulmonary hypertension, and death in the newborn. Surgical creation or enlargement of a ventricular septal defect (VSD) is palliative but may damage the conduction system or the atrioventricular valves in the newborn. This report presents a transcatheter approach to palliation for a newborn that had DORV with a restrictive ventricular septum. METHODS/RESULTS: A full-term infant girl (2.9 kg) referred for hypoxia (80% with room air) and murmur was found to have DORV, interrupted inferior vena cava, and restrictive VSD (95-mmHg gradient). Transhepatic access was performed, and an internal mammary (IM) catheter was advanced through the atrial septal defect and into the left ventricle. By transesophageal echocardiographic guidance, a Baylis radiofrequency perforation wire was used to cross the ventricular septum, and the defect was enlarged using a 4-mm cutting balloon. A bare metal stent then was deployed to maintain the newly created VSD. The patient did well after the procedure but required pulmonary artery banding 4 days later. She returned 5 months later with cyanosis and the development of obstructing right ventricle muscle bundles, requiring further surgical palliation. CONCLUSIONS: This report describes the first transcatheter creation of VSD in DORV with a restrictive ventricular septum in a newborn infant. Use of the radiofrequency catheter in combination with cutting balloon dilation and stent implantation is an efficient method for creating a VSD in such a patient.

Myocardial oxygen consumption change predicts left ventricular relaxation improvement in obese humans after weight loss.

Obesity adversely affects myocardial metabolism, efficiency, and diastolic function. Our objective was to determine whether weight loss can ameliorate obesity-related myocardial metabolism and efficiency derangements and that these improvements directly relate to improved diastolic function in humans. We studied 30 obese (BMI >30 kg/m2) subjects with positron emission tomography (PET) (myocardial metabolism, blood flow) and echocardiography (structure, function) before and after marked weight loss from gastric bypass surgery (N = 10) or moderate weight loss from diet (N = 20). Baseline BMI, insulin resistance, hemodynamics, left ventricular (LV) mass, systolic function, myocardial oxygen consumption (MVO2), and fatty acid (FA) metabolism were similar between the groups. MVO2/g decreased after diet-induced weight loss (P = 0.009). Total MVO2 decreased after dietary (P = 0.02) and surgical weight loss (P = 0.0006) and was related to decreased BMI (P = 0.006). Total myocardial FA utilization decreased (P = 0.03), and FA oxidation trended lower (P = 0.06) only after surgery. FA esterification and LV efficiency were unchanged. After surgical weight loss, LV mass decreased by 23% (Doppler-derived) E/E' by 33%, and relaxation increased (improved) by 28%. Improved LV relaxation related significantly to decreased BMI, insulin resistance, total MVO2, and LV mass but not FA utilization. Decreased total MVO(2) predicted LV relaxation improvement independent of BMI change (P = 0.02). Weight loss can ameliorate the obesity-related derangements in myocardial metabolism and LV structure and diastolic function. Decreased total MVO2 independently predicted improved LV relaxation, suggesting that myocardial oxygen metabolism may be mechanistically important in determining cardiac relaxation.

Defect closure in the lipomatous hypertrophied atrial septum with the Amplatzer muscular ventricular septal defect closure device: a case series.

Variations in the anatomy of the atrial septum can confound the transcatheter closure of atrial septal defects and patent foramen ovale. While lipomatous hypertrophy of the atrial septum is not frequently encountered, attempts to use standard atrial septal occlusion devices in such patient can lead to malapposition and continued shunt. Some operators have suggested that atrial septal hypertrophy is a relative contraindication to transcatheter-based closure techniques. We present a novel technique exploiting the features of the Amplatzer muscular ventricular septal defect occluder to treat atrial septal defects in the setting of lipomatous hypertrophy of the atrial septum in two patients.