Apparatus, system and methods for measuring a blood pressure gradient

摘要

An apparatus (100), control system (150) and methods are provided for directly measuring a pressure gradient, i.e. by real-time pressure measurements, with particular application for in situ measurement of transvalvular blood pressure gradients for the aortic valve and other heart valves, using minimally-invasive techniques. The apparatus takes the form of a multi-sensor assembly, e.g. enclosed within a micro-catheter or a steerable guidewire, and comprises a plurality of optical pressure sensors (10) is arranged along a length of the distal end portion (101), for measuring pressure simultaneously at each sensor location. For example, four MOMS optical pressure sensors (10), and optionally, a flow sensor (20), are incorporated into a distal end portion (101) having a diameter of 0.89 mm or less, and preferably 0.46 mm or less. Beneficially, all sensors are optically coupled, via respective optical fibers (11), to an optical coupler (112) at the proximal end of the multi-sensor apparatus, without requiring electrical connections.

主权项

1. An apparatus for measuring an intravascular blood pressure gradient, including a transvalvular blood pressure gradient for a heart valve, comprising:
a multi-sensor assembly contained within a tubular covering layer; the tubular covering layer comprising a micro-catheter or a coil of a steerable guidewire, having a proximal end and a distal end, the distal end comprising a flexible distal tip; the multi-sensor assembly comprising: an optical fiber bundle comprising a plurality of optical fibers and a plurality of optical sensors, each optical fiber having a proximal end and a distal end, each individual one of the plurality of optical sensors being attached and optically coupled to the distal end of a respective individual one of the plurality of optical fibers;distal ends of the plurality of optical fibers being arranged to form a sensor arrangement wherein said plurality of optical sensors have sensor locations spaced apart lengthwise from each other;
the multi-sensor assembly extending within the tubular covering layer from the proximal end into a distal end portion adjacent the distal end; the sensor arrangement, comprising said plurality of optical sensors, being located within the distal end portion for measuring pressure at respective sensor locations spaced apart along a length of 4 cm to 7 cm of the distal end portion of the tubular covering layer; the proximal end of each one of the plurality of optical fibers being optically coupled to an optical input/output end, for connection to a control system, said sensor arrangement providing for a measurement of pressure at each sensor location for determination by the control system of a blood pressure gradient; an aperture in the covering layer adjacent each optical sensor for fluid contact; at least one marker for locating the sensor arrangement; and at least the distal end portion of the covering layer having an outer diameter suitable for introduction intravascularly or intraluminally through a micro-catheter into the heart.