John-Peder Escobar Kvitting

Learn More
Mitral valve annuloplasty is a common surgical technique used in the repair of a leaking valve by implanting an annuloplasty device. To enhance repair durability, these devices are designed to increase leaflet coaptation, while preserving the native annular shape and motion; however, the precise impact of device implantation on annular deformation, strain,(More)
BACKGROUND The transit of blood through the beating heart is a basic aspect of cardiovascular physiology which remains incompletely studied. Quantification of the components of multidirectional flow in the normal left ventricle (LV) is lacking, making it difficult to put the changes observed with LV dysfunction and cardiac surgery into context. METHODS(More)
OBJECTIVES The durability of valve-sparing aortic root replacement with or without cusp repair in patients with bicuspid aortic valve (BAV) disease is questioned. We analyzed the results of 75 patients with a BAV undergoing Tirone David reimplantation valve-sparing aortic root replacement. METHODS Average age was 45 ± 10 years; 80% were male; 31% had 2+(More)
Progressive alterations in cardiac wall strains are a classic hallmark of chronic heart failure. Accordingly, the objectives of this study are to establish a baseline characterization of cardiac strains throughout the cardiac cycle, to quantify temporal, regional, and transmural variations of active fiber contraction, and to identify pathways of mechanical(More)
Turbulent flow, characterized by velocity fluctuations, is a contributing factor to the pathogenesis of several cardiovascular diseases. A clinical noninvasive tool for assessing turbulence is lacking, however. It is well known that the occurrence of multiple spin velocities within a voxel during the influence of a magnetic gradient moment causes signal(More)
PURPOSE To evaluate the feasibility of generalized phase-contrast magnetic resonance imaging (PC-MRI) for the noninvasive assessment of fluctuating velocities in cardiovascular blood flow. MATERIALS AND METHODS Multidimensional PC-MRI was used in a generalized manner to map mean flow velocities and intravoxel velocity standard deviation (IVSD) values in(More)
The objective of this study is to establish a mathematical characterization of the mitral valve annulus that allows a precise qualitative and quantitative assessment of annular dynamics in the beating heart. We define annular geometry through 16 miniature markers sewn onto the annuli of 55 sheep. Using biplane videofluoroscopy, we record marker coordinates(More)
Understanding the mechanics of the mitral valve is crucial in terms of designing and evaluating medical devices and techniques for mitral valve repair. In the current study we characterize the in vivo strains of the anterior mitral valve leaflet. On cardiopulmonary bypass, we sew miniature markers onto the leaflets of 57 sheep. During the cardiac cycle, the(More)
PURPOSE To assess in vitro the three-dimensional mean velocity field and the extent and degree of turbulence intensity (TI) in different prosthetic heart valves using a generalization of phase-contrast MRI (PC-MRI). MATERIALS AND METHODS Four 27-mm aortic valves (Björk-Shiley Monostrut tilting-disc, St. Jude Medical Standard bileaflet, Medtronic Mosaic(More)
BACKGROUND Over the past two decades elective valve-sparing aortic root replacement (V-SARR) has become more common in the treatment of patients with aortic root and ascending aortic aneurysms. Currently there are little data available to predict complications in the post-operative population. The study goal was to determine if altered flow patterns in the(More)