Incidence of Kidney Stones in the United States: The Continuous National Health and Nutrition Examination Survey.

Purpose: The incidence of kidney stones in the United States is currently unknown. Here, we assessed the incidence of kidney stones using recent, nationally representative data.

Materials And Methods: We used the National Health and Nutrition Examination Survey (NHANES) from 2015 to 2018.

The clinical anatomy and pathology of the human atrioventricular valves: implications for repair or replacement.

A critical understanding of cardiac anatomy is essential for design engineers and clinicians with the intent of developing and/or employing improved or novel technologies or therapies for treating an impaired atrioventricular valve. Likewise, such knowledge is required for directing translational research, including initiating preclinical research, assessing the feasibility of clinical trials, and performing first-in-man procedures. There are two atrioventricular valves in the human heart, namely the tricuspid and mitral valves.

The clinical anatomy and pathology of the human arterial valves: implications for repair or replacement.

A thorough understanding of valvar anatomy is essential for design engineers and clinicians in the development and/or employment of improved technologies or therapies for treating valvar pathologies. There are two arterial valves in the human heart--pulmonary and aortic valves. Both are complex structures whose normal anatomical components can vary greatly between individuals.

Accuracy of aortic annular measurements obtained from three-dimensional echocardiography, CT and MRI: human in vitro and in vivo studies.

Objectives: To determine the accuracy of calcium-containing rings measurements imaged by three-dimensional echocardiography (3DE), multi-slice CT (MSCT) and cardiac magnetic resonance (CMR) under ideal conditions against the true ring dimensions. To compare the accuracy of aortic annulus (AoA) measurements in ex vivo human hearts using 3DE, MSCT and CMR. To determine the accuracy of AoA measurements in an in vivo human model.

Variations in Thebesian valve anatomy and coronary sinus ostium: implications for invasive electrophysiology procedures.

Aims: The coronary sinus (CS) is a commonly cannulated structure in patients undergoing electrophysiology studies, catheter ablation of arrhythmias, implantation of resynchronization therapy devices and, more recently, percutaneous mitral valve repair. The advent of these procedures has led to a renewed interest in the anatomy of the coronary venous system including its various components. To improve our understanding of this structure, we studied the anatomy of the human CS, including the valve that guards its ostium, the Thebesian valve.

Mitral leaflet anatomy revisited.

Objective: The aims of this work were to employ functional imaging capabilities of the Visible Heart laboratory and endoscopic visualization of mitral valves in perfusion-fixed specimens to better characterize variability in mitral valve leaflet anatomy and to provide a method to classify mitral leaflets that varies from the current nomenclature.

Methods: We gathered functional endoscopic video footage (11 isolated reanimated human hearts) and static endoscopic anatomical images (38 perfusion-fixed specimens) of mitral leaflets. Commissure and cleft locations were charted using Carpentier's accepted description.

Microanatomy of human left ventricular coronary veins.

We describe analyses of the microanatomy of major left ventricular veins, including their relationship to the myocardium. Immediately following fixation of six fresh human hearts, anterior interventricular veins (AIV), left marginal veins (LMV), posterior veins of the left ventricle (PVLV), and posterior interventricular veins (PIV) were sectioned in approximately 5 mm intervals perpendicular to the veins' length from base to apex. Slides were prepared, digitized, and analyzed; measurements were made of each vein's wall thickness, circumference, distance between vein wall and myocardium, and distance between vein wall and closest artery.

Cardiac device testing enhanced by simultaneous imaging modalities: the Visible Heart, fluoroscopy and echocardiography.

The evaluation of implantable cardiac devices requires innovative and critical testing in all phases of the design process. The recent development of an in vitro isolated heart model, the Visible Heart, allows for novel examination of device-tissue interactions to evaluate device placement and performance within a functioning heart. This model provides product designers with a rapid method to critically assess prototypes, thus expediting design decisions.

Excitation of the intrinsic conduction system through his and interventricular septal pacing.

Background: Direct His bundle pacing results in rapid synchronous ventricular activation. However, clinical experiences with such pacing have been associated with long procedure times and compromised pacing and sensing performance.

Methods: We evaluated myocardial activation sequences (AS) for pacing of the His bundle and peri-His region and assessed acute pacing performance using custom-designed plunge electrodes.

In vitro studies of human hearts.

Background: Isolated mammalian hearts have been used in numerous studies that have led to many important discoveries in cardiac physiology, pharmacology, and surgery. Multiple methods of perfusion have been described including retrograde and/or antegrade flows and crystalloid or blood perfusates. Furthermore, multiple species have been utilized for such studies including the following: rat, rabbit, guinea pig, canine, and swine.