Robert Lederman

BACKGROUND: Transcatheter aortic valve replacement (TAVR)-related coronary artery obstruction prediction remains unsatisfactory despite high mortality and novel preventive therapies. OBJECTIVES: This study sought to develop a predictive model for TAVR-related coronary obstruction in native aortic stenosis. METHODS: Preprocedure computed tomography and fluoroscopy images of patients in whom TAVR caused coronary artery obstruction were collected...

Transcaval aortic access is a versatile electrosurgical technique for large-bore arterial access through the wall of the abdominal aorta from the adjoining inferior vena cava. Although counterintuitive, its relative safety derives from the recognition that interstitial hydraulic pressure exceeds venous pressure, so arterial bleeding harmlessly decompresses into the nearby caval venous hole. Transcaval access has been performed in thousands of patients for transcatheter aortic valve replacement and endovascular thoracic aneurysm repair and to avoid limb ischemia in percutaneous mechanical circulatory support...

BACKGROUND: Oxygen-enhanced magnetic resonance imaging (OE-MRI) can be used to assess regional lung function without ionizing radiation. Inhaled oxygen acts as a T1-shortening contrast agent to increase signal in T1-weighted (T1w) images. However, increase in proton density from pulmonary hyperoxic vasodilation may also contribute to the measured signal enhancement. Our aim was to quantify the relative contributions of the T1-shortening and vasodilatory effects of oxygen to signal enhancement in OE-MRI in both swine and healthy volunteers...

Transcatheter electrosurgery describes the ability to cut and traverse tissue, at a distance, without an open surgical field and is possible using either purpose-built or off-the-shelf devices. Tissue traversal requires focused delivery of radiofrequency energy to a guidewire tip. Initially employed to cross atretic pulmonary valves, tissue traversal has enabled transcaval aortic access, recanalization of arterial and venous occlusions, transseptal access, and many other techniques. To cut tissue, the selectively denuded inner curvature of a kinked guidewire (the Flying-V) or a single-loop snare is energized during traction...

MIRTH (Myocardial Intramural Remodeling by Transvenous Tether) is a transcatheter ventricular remodeling procedure. A transvenous tension element is placed within the walls of the beating left ventricle and shortened to narrow chamber dimensions. MIRTH uses 2 new techniques: controlled intramyocardial guidewire navigation and EDEN (Electrocardiographic Radial Depth Navigation). MIRTH caused a sustained reduction in chamber dimensions in healthy swine. Midventricular implants approximated papillary muscles. MIRTH shortening improved myocardial contractility in cardiomyopathy in a dose-dependent manner up to a threshold beyond which additional shortening reduced performance...

BACKGROUND: Left ventricular (LV) contractility and compliance are derived from pressure-volume (PV) loops during dynamic preload reduction, but reliable simultaneous measurements of pressure and volume are challenging with current technologies. We have developed a method to quantify contractility and compliance from PV loops during a dynamic preload reduction using simultaneous measurements of volume from real-time cardiovascular magnetic resonance (CMR) and invasive LV pressures with CMR-specific signal conditioning...

Arthroscopy following shoulder arthroplasty has primarily been described as a diagnostic tool in the setting of unexplained pain. However, this tool also can be used to potentially manage postoperative stiffness and pain following reverse shoulder arthroplasty. This Technical Note provides a stepwise approach to assessing and addressing limitations in range of motion as well as causes of postoperative impingement following reverse shoulder arthroplasty.

PURPOSE: We describe a clinical grade, "active", monopole antenna-based metallic guidewire that has a continuous shaft-to-tip image profile, a pre-shaped tip-curve, standard 0.89 mm (0.035″) outer diameter, and a detachable connector for catheter exchange during cardiovascular catheterization at 0.55T. METHODS: Electromagnetic simulations were performed to characterize the magnetic field around the antenna whip for continuous tip visibility. The active guidewire was manufactured using medical grade materials in an ISO Class 7 cleanroom...

BACKGROUND: Restoring the native center of rotation (COR) in total shoulder arthroplasty (TSA) has been shown to improve post-surgical function, subjective outcomes and implant longevity. The primary purpose of this study was to compare postoperative radiographic restoration of the humeral center of rotation (COR) between short stem and stemless humeral implants by evaluating the mean COR shift between the two techniques. Secondary outcomes evaluated were comparisons of COR shift outliers, humeral head implant thickness and diameter, direction of COR shift and neck shaft angle (NSA)...

No abstract text is available yet for this article.

A cardiogenic shock patient with a history of a surgical mitral valve replacement presented to the hospital with critical mitral stenosis with thickening of prosthetic valve leaflets and thrombus in left atrial appendage. We considered TMVR inside of the degenerated bioprosthetic valve. However, there were two concerns during TMVR based on multimodality imaging assessment: 1) LVOT obstruction due to the surgical bioprosthetic leaflet, 2) stroke due to left atrial appendage thrombus. We performed TMVR with LAMPOON (laceration of the anterior leaflet of the surgical valve to prevent left ventricular outflow tract obstruction) for the bioprosthesis using cerebral protection...

Background: A clinical study comparing the hemodynamic outcomes of transcatheter mitral valve replacement (TMVR) with vs. without Laceration of the Anterior Mitral leaflet to Prevent Outflow Obstruction (LAMPOON) has never been designed nor conducted. Aims: To quantify the hemodynamic impact of LAMPOON in TMVR using patient-specific computational ( in silico ) models. Materials: Eight subjects from the LAMPOON investigational device exemption trial were included who had acceptable computed tomography (CT) data for analysis...

BACKGROUND: Transcatheter mitral valve repair is beneficial in patients with mitral regurgitation (MR), left ventricular dysfunction, and persistent symptoms despite maximally tolerated medical therapy. OBJECTIVES: The aim of this study was to evaluate the safety and feasibility of transcatheter mitral cerclage ventriculoplasty in patients with MR and either heart failure with reduced ejection fraction or preserved ejection fraction and in subjects with prior edge-to-edge repair but persistent or recurrent symptomatic MR...

Transcatheter electrosurgery is a versatile tool that can be used to cut cardiac tissue without the need for a sternotomy, cardiopulmonary bypass, and cardioplegia. With adequate imaging and suitable anatomy, any cardiac tissue can be cut. Thus, transcatheter electrosurgery can provide bespoke therapies for complex patients who often have no other good treatment options. In this review, we will discuss the common applications for electrosurgical tissue traversal and laceration, including transcaval access, BASILICA, LAMPOON, and ELASTA-Clip, summarizing the evidence and the key technical steps for each...

BACKGROUND: Quantitative assessment of dynamic lung water accumulation is of interest to unmask latent heart failure. We develop and validate a free-breathing 3D ultrashort echo time (UTE) sequence with automated inline image processing to image changes in lung water density (LWD) using high-performance 0.55 T cardiovascular magnetic resonance (CMR). METHODS: Quantitative lung water CMR was performed on 15 healthy subjects using free-breathing 3D stack-of-spirals proton density weighted UTE at 0...

No abstract text is available yet for this article.

No abstract text is available yet for this article.

OBJECTIVES: The aim of this study was to compare transcaval and transaxillary artery access for transcatheter aortic valve replacement (TAVR) at experienced medical centers in contemporary practice. BACKGROUND: There are no systematic comparisons of transcaval and transaxillary TAVR access routes. METHODS: Eight experienced centers contributed local data collected for the STS/ACC TVT Registry (Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry) between 2017 and 2020...

BACKGROUND: Left ventricular outflow tract obstruction complicates hypertrophic cardiomyopathy and transcatheter mitral valve replacement. Septal reduction therapies including surgical myectomy and alcohol septal ablation are limited by surgical morbidity or coronary anatomy and high pacemaker rates, respectively. We developed a novel transcatheter procedure, mimicking surgical myotomy, called Septal Scoring Along the Midline Endocardium (SESAME). METHODS: SESAME was performed in 5 naive pigs and 5 pigs with percutaneous aortic banding-induced left ventricular hypertrophy...

Coronary artery obstruction is a devastating complication of transcatheter aortic valve replacement (TAVR). Bioprosthetic or native Aortic Scallop Intentional Laceration to prevent Iatrogenic Coronary Artery Obstruction (BASILICA) is a transcatheter, electrosurgical technique that was developed to prevent obstruction due to sinus effacement or sinus sequestration. BASILICA creates a midline laceration of one (solo) or both (doppio) offending aortic leaflets and has been performed in over 1,000 patients at high risk for obstruction...