Vascular access ports and related methods

A vascular access port comprising:

• a base configured to be attached to a vessel, the base extending in at least a longitudinal direction and a lateral direction that are orthogonal to each other, wherein at least a portion of the base defines a footprint of the port at which the port is configured to contact the vessel when the base is attached to the vessel;
• a body extending away from the base in at least a vertical direction that is orthogonal to each of the longitudinal and lateral directions, wherein a height of the body in the vertical direction is sufficiently small such that the entire port can be implanted subcutaneously in a patient, wherein one or more of the body and the base define an outermost periphery of the port in the longitudinal and lateral directions, and wherein the outermost periphery, when projected vertically, defines a peripheral extent of the port;
• and
• a guidance passageway that is at least partially defined by the body and is configured to direct an access device into a vessel of a patient when the port is attached to the vessel, the guidance passageway comprising a proximal end and a distal end and defining a central axis that is non-vertical such that when the base is attached to a vessel, the central axis is at a non-perpendicular angle relative to a longitudinal axis of the vessel, wherein the guidance passageway is configured to constrain movement of an access device such that when the access device is advanced through the guidance passageway in a proximal-to-distal direction and a distal tip of the access device is at a position that is vertically even with at least a portion of the footprint, the distal tip of the access device is at an interior of the peripheral extent of the port.