Ventricular assist devices: history, patient selection, and timing of therapy.

Timing of therapy and selection of patients in the use of ventricular assist devices (VADs) can be difficult. In general, consideration for VAD implantation is appropriate in patients with endstage heart failure who are failing optimal medical therapy and in whom no alternative traditional surgical treatment options are available. However, identifying when a particular patient has reached this point is not always straightforward. There are a broad range of medical and surgical therapies for patients with overt heart failure, and this armamentarium is constantly expanding. The risks, benefits, and expected outcomes with VAD therapy have also undergone dramatic changes over the last decade. Advances in technology have led to a proliferation of newer generation devices that are smaller, lighter, easier to implant, and more reliable than previous generation devices. This, in turn, has led to a markedly improved risk-benefit ratio, with increased durability and reduced morbidity. The indications for the implantation of ventricular assist devices have also evolved over the last several years, and specific patient presentations and goals of therapy have led to specific indications. Device therapy has traditionally been classified as bridge to recovery, bridge to transplantation, and destination therapy. However, such designations may not be well defined at the time of implantation, and recovery and response following initiation of VAD support may allow patients to change from one classification to another. The current data regarding indications and timing of device implantation are reviewed.