Circulatory assist device with multi-leaflet valve

A method, comprising:

• positioning a blood pump device in the circulatory system of a patient, wherein the blood pump device comprises:
• a conduit having an inflow region and an outflow region:
• a volume displacement member arranged in the conduit;
• and
• an inlet valve arranged in the inflow region and comprising a plurality of leaflets, an upstream side, and a downstream side;
• and
• cyclically operating the volume displacement member between an expansion phase and a contraction phase;
• wherein the inlet valve transitions between an open state during the contraction phase to allow blood flow into the conduit, and a closed state during the expansion phase in which the valve substantially prevents blood flow out of the conduit through the inflow region, and
• wherein during the expansion phase, the inlet valve maintains the closed state under a pressure differential of up to at least about 500 mmHg from the downstream side to the upstream side, without allowing blood leakage from the downstream side to the upstream side.

A valve arrangement for a blood pump device, the valve arrangement comprising:

• a valve comprising a plurality of leaflets, an upstream side, and a downstream side, wherein the valve is operable in:
• an open state in which the leaflets permit fluid flow between the upstream side and the downstream side;
• and
• a closed state in which the leaflets substantially prevent fluid flow from the downstream side to the upstream side,
• wherein the valve is configured to maintain the closed state under a pressure differential of up to at least about 500 mmHg from the downstream side to the upstream side, without allowing fluid leakage from the downstream side to the upstream side.

A method, comprising:

• positioning a blood pump device in the circulatory system of a patient, wherein the blood pump device comprises:
• a conduit having an inflow region and an outflow region;
• a volume displacement member arranged in the conduit;
• and
• an inlet valve arranged in the inflow region and comprising a plurality of leaflets;
• and
• cyclically operating the volume displacement member between an expansion phase and a contraction phase,
• wherein the inlet valve transitions between an open state during the contraction phase to allow blood flow into the conduit, and a closed state during the expansion phase in which the valve substantially prevents blood flow out of the conduit through the inflow region, and
• wherein the valve repeatedly cycles between the open state and the closed state at a frequency of between about 500 beats per minute and about 5000 beats per minute.

A valve arrangement for a blood pump device, the valve arrangement comprising:

• a valve comprising a plurality of leaflets, an upstream side, and a downstream side, wherein the valve is operable in:
• an open state in which the leaflets permit fluid flow between the upstream side and the downstream side;
• and
• a closed state in which the leaflets substantially prevent fluid flow from the downstream side to the upstream side,
• wherein the valve is configured to repeatedly cycle between the open state and the closed state at a frequency of between about 500 beats per minute and about 5000 beats per minute.

A method, comprising:

• positioning a blood pump device in the circulatory system of a patient, wherein the blood pump device comprises:
• a conduit having an inflow region and an outflow region;
• a volume displacement member arranged in the conduit;
• and
• an inlet valve arranged in the inflow region and comprising a plurality of leaflets;
• and
• cyclically operating the volume displacement member between an expansion phase and a contraction phase,
• wherein the inlet valve transitions between an open state during the contraction phase to allow blood flow into the conduit, and a closed state during the expansion phase in which the valve substantially prevents blood flow out of the conduit through the inflow region, and
• wherein the inlet valve transitions from the closed state to the open state over no more than about 20% of the duration of the valve cycle.

A valve arrangement for a blood pump device, the valve arrangement comprising:

• a valve comprising a plurality of leaflets, an upstream side, and a downstream side, wherein the valve is operable in a valve cycle including:
• an open state in which the leaflets permit fluid flow between the upstream side and the downstream side;
• and
• a closed state in which the leaflets substantially prevent fluid flow from the downstream side to the upstream side,
• wherein the valve is configured to transition from the closed state to the open state over no more than about 20% of the duration of the valve cycle.

A blood pump device comprising:

• a pump body comprising:
• a conduit having an inflow region and an outflow region, wherein the conduit comprises an expandable support and a membrane covering at least a portion of the expandable support;
• a balloon arranged in the conduit and cyclically operable between an expansion phase and a contraction phase;
• and
• an inlet valve arranged in the inflow region and comprising a plurality of leaflets,
• wherein the inlet valve transitions between an open state during the contraction phase to allow blood flow into the conduit, and a closed state during the expansion phase in which the valve substantially prevents blood flow out of the conduit through the inflow region,
• wherein each leaflet comprises a base region comprising a first bending stiffness and an edge region comprising a second bending stiffness lower than the first bending stiffness, and
• wherein each leaflet is joined to the membrane of the conduit;
• a guidewire extending through the inlet valve;
• and
• a tubular member configured to slidably receive the guidewire, wherein the tubular member extends through the inlet valve and is configured to support the leaflets to substantially inhibit prolapsing of the leaflets.