VADs As Destination Therapy
How LVADs Evolved into a Permanent or Destination Therapy
According to the landmark REMATCH (Randomized Evaluation of Mechanical Assistance for the Treatment of Congestive Heart Failure) trial published in the November 2001 New England Journal of Medicine, end-stage heart failure patients who received an LVAD device (HeartMate® XVE, also known as HeartMate® I) had a 52.1% chance of surviving one year, compared with a 24.7% survival rate for patients on medical management.
At two years, however, the likelihood of survival was only 22.9% for the LVAD patients versus 8.1% for those on medical therapies. The use of LVAD as destination therapy remained rare while efforts were directed at improving pump technology.
In January of 2010 the HeartMate® II, a next generation device—smaller and now completely quiet—was approved by the FDA for destination therapy. In a head to head comparison with the earlier Heartmate® I device, the two year survival rate was 58% (HeartMate® II) versus 23% (HeartMate® XVE). In addition, patients reported significant improvements in their quality of life. Currently Thoratec's HeartMate® II is the preferred choice for destination therapy:
At present, modern device therapy in appropriately selected patients offers a 60% likelihood of surviving two years, whereas survival on currently available medical therapy remains below 10%.
We are actively working to further improve these impressive outcomes and are employing several third generation devices in clinical trials.
For Clinicians: Indications for Advanced Heart Failure Therapy LVAD
Left ventricular assist devices (LVADs) represent a promising option as a destination therapy for advanced-stage heart failure patients who do not respond to conventional therapy and are not good candidates for heart transplantation.
The following list of risk factors offers a quick reference for cardiologists tring to identify patients who should be considered for an LVAD as treatment for advanced heart failure. These include individuals with reduced LVEF (<30%) and
- Inability to walk one block without shortness of breath despite optimal medical therapy (OMM = ACE inhibitor, ARB or beta blocker)
- Two hospitalizations in the past 6 months despite OMM
- Inability to tolerate (OMM) due to hypotension
- Slowly declining kidney function
- Symptoms of CHF and renal, liver, and lung dysfunction must not be severe and irreversible.
It is strongly recommended that physicians explore the option of VAD implantation in early stage of the patient's disease. The further the condition progresses, the less likelihood the patient will be considered an appropriate candidate for a mechanical assist device.
As noted above, severe end organ damage such as liver cirrhosis and/or severe COPD, and/or end-stage renal disease requiring dialysis are contraindications. It is extremely important to consider LVAD therapy before the patient suffers these consequences.