An inflow cannula assembly, for transporting blood between a heart chamber and a ventricular assist device, comprising: a deformable polymeric cannula, comprising: a first end, being used as an intake to be inserted into heart chamber, and being formed to have a bellmouth; a second end, being formed to have a flange ramp; and a conduit, wherein the first end and the second end are integrally joined by the conduit, and an entire inner surface of the cannula is smooth and seamless; a male fastener and a female fastener, wherein the male fastener and the female fastener are screw interconnected with the male fastener anchored on the cannula; characterized in that the inflow cannula assembly further comprises: a ventricular assist device coupler; and a ventricular assist device inlet adapter configured to interface with the VAD, wherein: the second end is configured to interface with the VAD via the VAD inlet adapter; the VAD coupler connects the second end with the VAD inlet adapter, and the VAD coupler includes a sandwiched flange base and a pair of collars pinned on the sandwiched flange base, wherein the collars have at least one internal grooved slot to receive and compress the sandwiched flange base, the flange ramp of the cannula, and a beak flange of the VAD inlet adapter; and the VAD inlet adapter includes a wedge-shaped beak to be interfaced with the second end, the beak flange to be accepted by the VAD coupler, and a base integrated with the VAD. a deformable polymeric cannula, comprising: a first end, being used as an intake to be inserted into heart chamber, and being formed to have a bellmouth; a second end, being formed to have a flange ramp; and a conduit, wherein the first end and the second end are integrally joined by the conduit, and an entire inner surface of the cannula is smooth and seamless; a first end, being used as an intake to be inserted into heart chamber, and being formed to have a bellmouth; a second end, being formed to have a flange ramp; and a conduit, wherein the first end and the second end are integrally joined by the conduit, and an entire inner surface of the cannula is smooth and seamless; a male fastener and a female fastener, wherein the male fastener and the female fastener are screw interconnected with the male fastener anchored on the cannula; characterized in that the inflow cannula assembly further comprises: a ventricular assist device coupler; and a ventricular assist device inlet adapter configured to interface with the VAD, wherein: the second end is configured to interface with the VAD via the VAD inlet adapter; the VAD coupler connects the second end with the VAD inlet adapter, and the VAD coupler includes a sandwiched flange base and a pair of collars pinned on the sandwiched flange base, wherein the collars have at least one internal grooved slot to receive and compress the sandwiched flange base, the flange ramp of the cannula, and a beak flange of the VAD inlet adapter; and the VAD inlet adapter includes a wedge-shaped beak to be interfaced with the second end, the beak flange to be accepted by the VAD coupler, and a base integrated with the VAD. a ventricular assist device coupler; and a ventricular assist device inlet adapter configured to interface with the VAD, wherein: the second end is configured to interface with the VAD via the VAD inlet adapter; the VAD coupler connects the second end with the VAD inlet adapter, and the VAD coupler includes a sandwiched flange base and a pair of collars pinned on the sandwiched flange base, wherein the collars have at least one internal grooved slot to receive and compress the sandwiched flange base, the flange ramp of the cannula, and a beak flange of the VAD inlet adapter; and the VAD inlet adapter includes a wedge-shaped beak to be interfaced with the second end, the beak flange to be accepted by the VAD coupler, and a base integrated with the VAD. the second end is configured to interface with the VAD via the VAD inlet adapter; the VAD coupler connects the second end with the VAD inlet adapter, and the VAD coupler includes a sandwiched flange base and a pair of collars pinned on the sandwiched flange base, wherein the collars have at least one internal grooved slot to receive and compress the sandwiched flange base, the flange ramp of the cannula, and a beak flange of the VAD inlet adapter; and the VAD inlet adapter includes a wedge-shaped beak to be interfaced with the second end, the beak flange to be accepted by the VAD coupler, and a base integrated with the VAD.