From the Guidelines
A Left Ventricular Assist Device (LVAD) is a mechanical pump that is surgically implanted to help a weakened heart pump blood throughout the body, specifically assisting the left ventricle and improving survival and quality of life for patients with advanced heart failure. The device takes blood from the left ventricle and pumps it into the aorta, effectively bypassing the damaged heart muscle. LVADs are primarily used in patients with advanced heart failure who are either waiting for a heart transplant (bridge to transplant), not eligible for transplantation (destination therapy), or need temporary support while their heart recovers (bridge to recovery) 1. The device consists of an internal pump connected to external components including a controller and power source that the patient carries. Patients with LVADs require ongoing anticoagulation therapy, typically warfarin with a target INR of 2.0-3.0, plus aspirin 81-325 mg daily to prevent blood clots from forming in the device, as well as strict protocols for battery management, driveline care to prevent infections, and regular medical follow-ups 1. Some key terms related to LVADs include:
- Bridge to decision (BTD)/Bridge to bridge (BTB): use of short-term MCS in patients with cardiogenic shock until haemodynamics and end-organ perfusion are stabilized
- Bridge to candidacy (BTC): use of MCS to improve end-organ function in order to make an ineligible patient eligible for heart transplantation
- Bridge to transplantation (BTT): use of MCS to keep patient alive who is otherwise at high risk of death before transplantation until a donor organ becomes available
- Bridge to recovery (BTR): use of MCS to keep patient alive while their heart recovers
- Destination therapy (DT): long-term use of MCS as an alternative to transplantation in patients with end-stage HF ineligible for transplantation or long-term waiting for heart transplantation 1. Current 2–3-year survival rates in carefully selected patients receiving the latest continuous flow devices are excellent, and comparable to early survival after heart transplantation 1. However, despite technological improvements, bleeding, thromboembolism, infection, and device failure remain significant problems, and these issues, plus the high cost of devices and implantation, have limited their wider use 1. It is recommended that such devices are only implanted and managed at tertiary heart failure centres with appropriately trained, specialist HF physicians and surgeons 1. In some patients, LV reverse remodelling and functional improvement during MCS permit removal of the ventricular assist devices (‘bridge-to-recovery, BTR)’ 1. The difficult decision to withdraw MCS may need to be made if the patient does not become eligible and DT is not possible 1. Overall, LVADs have significantly improved survival and quality of life for many heart failure patients who would otherwise have very limited treatment options 1.
From the Research
Definition of LVAD
- A Left Ventricular Assist Device (LVAD) is a mechanical circulatory support device used to treat advanced heart failure 2, 3, 4, 5, 6.
- It is designed to assist the left ventricle of the heart in pumping blood, thereby alleviating left-sided congestion and reducing right ventricular burden 5.
Purpose and Use of LVAD
- LVADs are used as a bridge to heart transplantation or as destination therapy for patients with end-stage heart failure who are not candidates for heart transplantation 3, 4.
- They can improve survival and functional capacity in patients with advanced heart failure, and their use has increased significantly in recent years 3, 4.
Types of LVADs
- There are different types of LVADs, including continuous-flow LVADs and pulsatile-flow LVADs 6.
- The choice of LVAD type depends on the individual patient's needs and the specific clinical scenario 6.
Complications and Challenges
- Right heart failure is a significant complication that can occur after LVAD implantation, and it is a major driver of morbidity and mortality 5.
- Predicting the progression of right heart failure after LVAD implantation is challenging due to complex hemodynamic interactions and the lack of established guidelines 5.