A cardiac pump and an assist system is provided to increase blood ejection from a compromised heart. An implantable cardiac pump acting as an assist device includes an attachment system and locating features that enable a minimally invasive procedure to implant and deploy one or more aortic blood pumps in a patient. The cardiac pumps are replaceable without resort to a surgical procedure. Monitoring of cardiac pump operation allows for replacement in advance of chamber failure. The cardiac pump and assist system do not appreciably sheer blood being accelerated through inflation-deflation cycling so as to limit clot associated side effects of operation of a cardiac assist device.

Described herein are pumps that linearly reciprocate to assist with circulating blood within the body of a patient. Red blood cell damage may be avoided or minimized by such linear pump movement. The linearly reciprocating movement may also generate a pulsatile pumping cycle that mimics the natural pumping cycle of the heart. The pumps may be configured to reside at various body locations. For example, the pumps may be situated within the right ventricle, the left ventricle, the ascending aorta, the descending aorta, the thoracic aorta, or the abdominal aorta. In some instances, the pump may reside outside the patient.

Disclosed is a ventricular decompression and assisting apparatus (100). The apparatus (100) includes a pigtail and a catheter that is introduced percutaneously into a femoral/radial/brachial vein or artery and is advanced into the ventricle where blood is drawn and mechanically pumped back with an external blood pump (40) and pumped back downstream into the aorta (2) or venous system or the pulmonary artery using another suitable catheter from a second access into the femoral/radial/brachial artery or any vein and with tip thereof positioned at a desired location thus forming a ventricular vent loop. The desired cardiac circulation is maintained with smart pumping, monitoring and control while relieving the load on the heart muscle to rebuild strength thereof. The apparatus (100) provides user friendly simplified approach to ventricular venting and unloading as a means for mechanical circulatory support of the left heart, right heart or both circulations even simultaneously.

A dual lumen coaxial cannula assembly includes a first infusion tube having a first elongate body defining a first lumen therethrough, the first infusion tube having a proximal end, a distal end, and a sidewall extending circumferentially therebetween. A second drainage tube is co-axially aligned with the first infusion tube and has a second elongate body with a second lumen defined by a space between the first infusion tube and the second drainage tube. The second drainage tube has a proximal end, a distal end, and a sidewall extending circumferentially therebetween. A connector is attached to the proximal end of the first infusion tube and the proximal end on the second drainage tube. The cannula assembly further includes a distal tip connected to the distal end of the first elongate body and made of a material having a lower hardness than a hardness of the first elongate body.

A spring (3, 3) comprising a plurality of elements (30), each element (3) comprising a rigid portion (31) and a flexible beam (32), the extremities (320, 321) of the flexible beam being supported by the rigid portion (31), the flexible beam (32) having a single stable position, so that the flexible beam can be deformed when a pressure is exerted between said extremities in the direction of the rigid portion (31), and returns to said single stable position when the pressure is released, and wherein the rigid portion (31) of at least one element (30) is in contact with the flexible beam (32) of the next element between said extremities (320, 321) of the flexible beam (32), so that the spring has a negative stiffness over an operating range. The arrangement ensures a pure radial compression/expansion of the spring.

A spring (3, 3) comprising a plurality of elements (30), each element (3) comprising a rigid portion (31) and a flexible beam (32), the extremities (320, 321) of the flexible beam being supported by the rigid portion (31), the flexible beam (32) having a single stable position, so that the flexible beam can be deformed when a pressure is exerted between said extremities in the direction of the rigid portion (31), and returns to said single stable position when the pressure is released, and wherein the rigid portion (31) of at least one element (30) is in contact with the flexible beam (32) of the next element between said extremities (320, 321) of the flexible beam (32), so that the spring has a negative stiffness over an operating range. The arrangement ensures a pure radial compression/expansion of the spring.

A blood pump comprises a pump casing a blood flow inlet and a blood flow outlet connected by a passage, and an impeller. The impeller comprises blades configured to convey blood from the blood flow inlet to the blood flow outlet, the impeller being supported in the pump casing by at least one contact-type bearing comprising a surface of the impeller facing a surface of the pump casing. At least one wash out channel extends through the impeller and is in fluid connection with the passage via a first opening and with the bearing via a second opening. The wash out channel is operatively associated with a secondary pump for pumping blood through the wash out channel towards the bearing. The secondary pump is formed at least partially by said at least one wash out channel extending through the impeller along a direction having at least one tangential directional component.

The present invention discloses a self-sealing cannula and methods of its use. The self-sealing cannula can be minimally invasively placed into the heart for drawing and/or returning blood with a self-sealing function at the interface of the blood access site. The disclosed cannula can be implemented as a single lumen cannula or a double lumen cannula, which can be used with ventricular assist devices for heart support or pump-oxygenators for ECMO and respiratory support. Through a self-sealing mechanism fixed on the ventricular wall or atrial wall, a cannula body is attached to the self-sealing fixture and blood is drawn into the lumen via an external pump and returned to the circulation system through a separate cannula. In the case of the double lumen cannula embodiment, the blood will be drawn into the drainage lumen of the double lumen cannula and returned through an infusion lumen at the desired location. The present invention achieves minimally invasive insertion without surgical sutures to the heart, and allows for optimal drainage of the blood from the heart. With use of the double lumen cannula, it prevents need for multiple cannulation sites, and greatly reduces the blood recirculation. Removal of the cannula is simplified without need for suturing or insertion of a plugging member.

The disclosure provides a method of placing a cardiac drainage cannula into a patient's heart. In some embodiments, the method comprises the steps of (a) inserting the cannula percutaneously into an internal jugular vein, (b) advancing the cannula through the internal jugular vein and into the right atrium of the heart, and (c) advancing the cannula through the atrial septum into the left atrium of the heart. Further aspects of the disclosure provide a method of draining blood from the left atrium or left ventricle of a patient's heart using a cardiac drainage cannula. The disclosure also provides a cardiac drainage cannula and a mechanical circulatory support system.

Systems and related methods for supplying power to a medical device employ serially-connectable portable batteries. A method of supplying electrical power to a medical device includes discharging a first external battery to output electrical power to a second external battery. Distribution of the electrical power received by the second external battery is controlled to simultaneously charge the second external battery and output electrical power from the second external battery to supply electrical power to the medical device.