title: Parametric ultrasound and fluoroscopy image fusion for guidance of left ventricle lead placement in cardiac resynchronization therapy.
abstract: Recent studies show that the response rate to cardiac resynchronization therapy (CRT) could be improved if the left ventricle (LV) is paced at the site of the latest mechanical activation, but away from the myocardial scar. A prototype system for CRT lead placement guidance that combines LV functional information from ultrasound with live x-ray fluoroscopy was developed. Two mean anatomical models, each containing LV epi-, LV endo- and right ventricle endocardial surfaces, were computed from a database of 33 heart failure patients as a substitute for a patient-specific model. The sphericity index was used to divide the observed population into two groups. The distance between the mean and the patient-specific models was determined using a signed distance field metric (reported in mm). The average error values for LV epicardium were [Formula: see text] and for LV endocardium were [Formula: see text]. The validity of using average LV models for a CRT procedure was tested by simulating coronary vein selection in a group of 15 CRT candidates. The probability of selecting the same coronary branch, when basing the selection on the average model compared to a patient-specific model, was estimated to be [Formula: see text]. This was found to be clinically acceptable.
authors.affiliation: Center for Cardiological Innovation , Songsvannsveien 9, Oslo 0372, Norway ; GE Vingmed Ultrasound AS , Strandpromenaden 45, Horten 3183, Norway ; University of Oslo , Department of Informatics, Gaustadalléen 23 B, Oslo 0373, Norway.
authors.forename: Aleksandar
authors.initials: A
authors.lastname: Babic
authors.affiliation: Center for Cardiological Innovation , Songsvannsveien 9, Oslo 0372, Norway ; Oslo University Hospital , Department of Cardiology and Pediatrics, P.O. Box 1072, Blindern, Oslo 0316, Norway.
authors.forename: Hans Henrik
authors.initials: HH
authors.lastname: Odland
authors.affiliation: GE Vingmed Ultrasound AS , Strandpromenaden 45, Horten 3183, Norway.
authors.forename: Olivier
authors.initials: O
authors.lastname: Gérard
authors.affiliation: Center for Cardiological Innovation , Songsvannsveien 9, Oslo 0372, Norway ; GE Vingmed Ultrasound AS , Strandpromenaden 45, Horten 3183, Norway ; University of Oslo , Department of Informatics, Gaustadalléen 23 B, Oslo 0373, Norway.
authors.forename: Eigil
authors.initials: E
authors.lastname: Samset
keywords: cardiac modelling; cardiac resynchronization therapy; echocardiography; image fusion; strain imaging