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Background: Transcatheter mitral valve replacement is a novel therapeutic approach aiming to treat patients with severe mitral regurgitation. This study aimed to evaluate the biological and technical performance of a novel transseptal transcatheter mitral valve replacement system (Cephea Valve Technologies, Santa Cruz, CA) in a preclinical model. Methods: Biological performance and healing response were evaluated following open-heart surgical implantation procedures in 10 sheep utilizing an antegrade transatrial access. Valve performance was assessed with fluoroscopy, echocardiography, and histology at 30 (n=2), 60 (n=3), and 90 days (n=5). Feasibility of transseptal valve delivery and performance was tested acutely in 10 pigs. Results: In the chronic studies, all animals survived without problems until completion of the study. The hemodynamics of the study valves were excellent with low rates of paravalvular leak. There was no left ventricular outflow tract obstruction. Pathological evaluation showed excellent position and condition of the mitral implants without evidence for thrombosis, endocarditis, or excessive calcification. Subsequently, mitral valves were implanted in 10 pigs using a dedicated transseptal delivery system. The implants remained in stable position with excellent hemodynamic profile. Correct valve position and function was confirmed by echocardiography and autopsy. Conclusions: The transseptal delivery of the Cephea transcatheter mitral valve replacement system in an experimental model was feasible and safe. The chronic studies demonstrated a favorable healing response. Further human studies are needed to evaluate the performance of this novel valve system in patients with severe mitral regurgitation.

Background A novel remotely controlled steerable guide catheter has been developed to enable precise manipulation and stable positioning of any eight French (Fr) or smaller electrophysiological catheter within the heart for the purposes of mapping and ablation. Objective To report our initial experience using this system for remotely performing catheter ablation in humans. Methods Consecutive patients attending for routine ablation were recruited. Various conventional diagnostic catheters were inserted through the left femoral vein in preparation for treating an accessory pathway (n = 1), atrial flutter (n = 2) and atrial fibrillation (n = 7). The steerable guide catheter was inserted into the right femoral vein through which various irrigated and non-irrigated tip ablation catheters were used. Conventional endpoints of loss of pathway conduction, bidirectional cavotricuspid isthmus block and four pulmonary vein isolation were used to determine acute procedural success. Results Ten patients underwent remote catheter ablation using conventional and/or 3D non-fluoroscopic mapping technologies. All procedural endpoints were achieved using the robotic control system without manual manipulation of the ablation catheter. There was no major complication. A radiation dosimeter positioned next to the operator 2.7 m away from the X-ray source showed negligible exposure despite a mean cumulative dose area product of 7,281.4 cGycm2 for all ten ablation procedures. Conclusions Safe and clinically effective remote navigation of ablation catheters can be achieved using a novel remotely controlled steerable guide catheter in a variety of arrhythmias. The system is compatible with current mapping and ablation technologies Remote navigation substantially reduces radiation exposure to the operator. Electronic supplementary material The online version of this article (doi:10.1007/s10840-007-9184-z) contains supplementary material, which is available to authorized users.

An automated medical system comprises a first instrument assembly including a first ultrasound transducer having a first transducer field of view that transmits and receives ultrasound signals in imaging planes disposed circumferentially about a guide instrument, and a second instrument assembly including a second ultrasound transducer having a second transducer field of view coupled to one of a second flexible guide instrument and a working instrument. A computing system is operatively coupled to the respective first and second transducers and configured to determine a relative spatial orientation of the respective first and second transducers based at least in part on detecting a signal transmitted by one of the first and second transducers and received by the other of the first and second transducers, the received signal having an amplitude indicating the receiving one of the transducers is in the field of view of the transmitting one of the transducers.

A system and method for recording and depicting ultrasound images of a moving object are disclosed. In a preferred embodiment, ultrasound images are acquired as the field of view of an ultrasound probe is advanced across the tissues of interest during a resting period between periods of relatively large-scale heart cycle motion. A series of images acquired during a particular resting period may be represented as a three-dimensional volume image, and the comparison of volume images from adjacent cardiac resting periods enables three-dimensional volume image modulation analysis which may be presented for a user as a moving volume image of the objects of interest within the field of view.