Device mediated optimisation of cardial resynchronisation atrio-ventricular and/or inter-ventricular intervals

摘要

Bi-ventricular pacemaker systems have an additional lead which is in contact with the left ventricle. In bi-ventricular pacemakers with defibrillator capabilities, defibrillating coils are typically placed within the right ventricle and often the superior vena-cava. Changes in electrical impedance (electrical resistance) between the pole(s) of the left ventricular lead and the pole(s) and/or coils of the right ventricular lead occur during the cardiac cycle of contraction and relaxation. These change in electrical impedance during the cardiac cycle can be measured. The changes in inter-ventricular impedance may be used to optimise the atrio-ventricular delay and/or the inter-ventricular delay without the need to employ echocardiography. Following implantation of the left ventricular and right ventricular leads and attachment of the permanent pacemaker generator or internal cardiac defibrillator generator, the generator can measure changes in inter-ventricular impedance and periodically alter the atrio-ventricular and or inter-ventricular delay to maintain optimised delays.