# US 12,377,258 B2 · External drive unit for an implantable heart assist pump > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,377,258 B2 - Document ID: US12377258B2 - Status: Granted - Kind: B2 - Application number: 18/639,196 - Filed: 2024-04-18 - Published: 2024-12-05 - Granted: 2025-08-05 - Earliest claimed: 2017-04-07 - Assignees: Ecp Entwicklungsgesellschaft Mbh - Applicants: ECP Entwicklungsgesellschaft mbH - Inventors: Gerd Spanier; Maxim Daschewski - Web page: https://patentgrep.com/patent/US12377258B2 ## CPC - A61M 60/829: having a purge fluid supply - A61M 25/02: Holding devices, e.g. on the body - A61M 60/13: by means of a catheter allowing explantation, e.g. catheter pumps temporarily introduced via the vascular system - A61M 60/148: in line with a blood vessel using resection or like techniques, e.g. permanent endovascular heart assist devices - A61M 60/174: discharging the blood to the ventricle or arterial system via a cannula internal to the ventricle or arterial system - A61M 60/216: including a rotating member acting on the blood, e.g. impeller - A61M 60/237: the blood flow through the rotating member having mainly axial components, e.g. axial flow pumps - A61M 60/414: transmitted by a rotating cable, e.g. for blood pumps mounted on a catheter - A61M 60/825: Contact bearings, e.g. ball-and-cup or pivot bearings - A61M 60/871: Energy supply devices; Converters therefor - A61M 60/88: Percutaneous cables - A61M 2025/0266: {using pads, patches, tapes or the like} - A61M 2205/04: implanted - A61M 2205/3606: cooled - A61M 2205/3666: using heat loss of a motor - A61M 2205/8262: connectable to external power source, e.g. connecting to automobile battery through the cigarette lighter - A61M 2209/088: on the body - A61M 2210/086: Legs - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} ## Abstract An external drive unit for an implantable heart assist pump is provided. The drive unit comprises a motor housing, a transcutaneous drive shaft and a motor for driving the heart assist pump. The motor is connectable to the heart assist pump via the drive shaft, and the motor is arranged inside the motor housing. The drive unit further comprises a catheter surrounding the drive shaft and a purge line for injecting a purge medium into a lumen of the catheter or into a space between the catheter and the drive shaft. The purge line is in thermal contact with an outer surface of the motor housing and/or with an outer surface of a proximal section of the catheter. Due to the thermal contact heat is transferred from the outer surface of the catheter in the proximal section and/or from the outer surface of the motor housing to the purge medium. ## Claims ### Claim 1 A heart assist system comprising: an implantable heart assist pump; and an external drive unit for the implantable heart assist pump, the external drive unit comprising: an external drive unit housing comprising: a motor housing arranged inside the external drive unit housing; a transcutaneous drive shaft; a motor for driving a heart assist pump, wherein the motor is configured to connect to the heart assist pump via the drive shaft and wherein the motor is arranged inside the motor housing; and a catheter surrounding the drive shaft; and a purge line for injecting a purge medium into a lumen of the catheter or into a space between the catheter and the drive shaft, wherein the purge line extends through an opening in a side of the external drive unit housing and extends between the external drive unit housing and the motor housing, wherein the purge line is in thermal contact with at least one of an outer surface of the motor housing or an outer surface of a proximal section of the catheter. ### Claim 2 (depends on 1) The heart assist system of claim 1, wherein the proximal section of the catheter is arranged within the external drive unit housing. ### Claim 3 (depends on 1) The heart assist system of claim 1, wherein the purge line is configured to guide the purge medium such that: the purge medium first comes into thermal contact with at least one of the outer surface of the motor housing or the outer surface of the proximal section of the catheter, and the purge medium is afterwards injected into the lumen of the catheter or into the space between the catheter and the drive shaft. ### Claim 4 (depends on 3) The heart assist system of claim 3, wherein the purge line is in thermal contact with both the outer surface of the motor housing and the outer surface of the proximal section of the catheter. ### Claim 5 (depends on 4) The heart assist system of claim 4, wherein the purge line is fully extracorporeal. ### Claim 6 (depends on 5) The heart assist system of any of claim 5, wherein the purge line is configured to guide the purge medium such that: the purge medium first comes into thermal contact with the outer surface of the proximal section of the catheter, and the purge medium afterwards comes into thermal contact with the outer surface of the motor housing. ### Claim 7 (depends on 1) The heart assist system of claim 1, wherein the motor comprises a stator and a rotor connected to the drive shaft, wherein the rotor is rotatably mounted and wherein a fluid gap is formed between the rotor and the stator, wherein the fluid gap is in fluid connection with a purge opening for injecting the purge medium into the fluid gap, and wherein the purge line is configured to connect to the purge opening. ### Claim 8 (depends on 7) The heart assist system of claim 7, wherein the purge line and the fluid gap are configured to guide the purge medium such that: the purge medium first comes into thermal contact with at least one of the outer surface of the motor housing or the outer surface of the proximal section of the catheter, the purge medium is afterwards injected into the fluid gap between the rotor and the stator, and the purge medium is afterwards injected into the lumen of the catheter or into the space between the catheter and the drive shaft. ### Claim 9 (depends on 1) The heart assist system of claim 1, wherein the purge line is configured to guide a flow of the purge medium in a proximal direction in an area in which the purge line is in thermal contact with at least one of the outer surface of the motor housing or the outer surface of the proximal section of the catheter prior to injection of the purge medium into the lumen of the catheter or into the space between the catheter and the drive shaft. ### Claim 10 (depends on 1) The heart assist system of claim 1, wherein the purge line encircles at least one of the motor housing or the proximal section of the catheter in an area in which the purge line is in thermal contact with at least one of the outer surface of the motor housing or the outer surface of the proximal section of the catheter. ### Claim 11 (depends on 10) The heart assist system of claim 10, wherein the purge line runs around at least one of the motor housing or the proximal section of the catheter in a helical manner in the area in which the purge line is in thermal contact with at least one of the outer surface of the motor housing or the outer surface of the proximal section of the catheter. ### Claim 12 (depends on 11) The heart assist system of claim 11, wherein the purge line runs around the proximal section of the catheter in a helical manner in the area in which the purge line is in thermal contact with the outer surface of the proximal section of the catheter. ### Claim 13 (depends on 1) The heart assist system of claim 1, wherein an overall thermal conductance between an interior surface of the purge line and an interior surface of the motor housing may amount to at least five times an overall thermal conductance between the interior surface of the purge line and an interior surface of the external drive unit housing. ### Claim 14 (depends on 13) The heart assist system of claim 13, wherein the overall thermal conductance between the interior surface of the purge line and the interior surface of the motor housing may amount to at least ten times the overall thermal conductance between the interior surface of the purge line and the interior surface of the external drive unit housing. ### Claim 15 (depends on 1) The heart assist system of claim 1, wherein a part of the purge line runs between the motor housing and the external drive unit housing. ### Claim 16 (depends on 1) The heart assist system of claim 1, wherein a part of the purge line runs between the proximal section of the catheter and the external drive unit housing. ### Claim 17 (depends on 1) The heart assist system of claim 1, further comprising a thermal insulator arranged between the purge line and the external drive unit housing. ### Claim 18 (depends on 1) The heart assist system claim 1, further comprising a heat spreader comprising a contact surface configured to contact a skin of a patient, wherein the contact surface is configured to connect with the motor in a thermally-conductive manner to transfer heat generated by the motor to tissue of the patient. ### Claim 19 (depends on 18) The heart assist system of claim 18, wherein the heat spreader has an area and the heat spreader is flexible in at least a portion of its area. ### Claim 20 (depends on 1) The heart assist system of claim 1, wherein the motor is connected to the drive shaft via a coupling.