title: Geometrically accurate transaortic mapping of left ventricular endocardial activation during surgery.
abstract: A device was developed for mapping left ventricular endocardial activation through the aortic valve during surgery. It uses an exploring electrode at the tip of a hand-held probe that is mounted on a mechanical arm with six joints whose movements are digitized by a computer while the position of the probe tip is calculated continuously. The probe is inserted by the surgeon into the left ventricle retrogradely through the aortic valve after the patient is on total cardiopulmonary bypass, the aorta has been opened and the coronary arteries cannulated. The electrode position relative to the aortic valve and left ventricular apex is displayed continuously on a computer screen. When electrograms are recorded from the probe, their positions are displayed on the screen relative to a stylized grid of the left ventricular endocardial surface and are color-coded to indicate the activation sequence. In a patient with nonischemic ventricular tachycardia, the arrhythmia was successfully mapped and cryoablated with use of the device. The device will be developed so that a cryoprobe can be substituted for the exploring electrode and positioned at the source of activation determined by the map.
authors.affiliation: Department of Cardiological Sciences, St. George's Hospital Medical School, London, England.
authors.forename: R C
authors.initials: RC
authors.lastname: Saumarez
authors.forename: D J
authors.initials: DJ
authors.lastname: Parker
authors.forename: A J
authors.initials: AJ
authors.lastname: Camm
mesh_terms: D000328:Adult; D001021:Aortic Valve; D001022:Aortic Valve Insufficiency / Q000503:physiopathology / Q000601:surgery; D003116:Color; D003201:Computers; D003452:Cryosurgery; D004562:Electrocardiography / Q000295:instrumentation* / Q000379:methods; D004699:Endocardium / Q000503:physiopathology*; D004867:Equipment Design; D006350:Heart Valve Prosthesis; D006801:Humans; D007430:Intraoperative Care / Q000295:instrumentation* / Q000379:methods; D008297:Male; D013610:Tachycardia / Q000503:physiopathology / Q000601:surgery; D016277:Ventricular Function, Left / Q000502:physiology*