Ventricular Assist Devices In 2012/13, we raised funds to buy 10 new ventricular assist devices Ventricular assist devices (VADs) are transplanted in patients while they wait for a suitable heart transplant, which can range from a period of two weeks to eight years. Harefield Hospital has the largest ventricular assist device service in the UK, and is known throughout the world as a leader in VAD technologies. Thanks to the generosity of our donors, we’ve been able to provide a lifeline for many more seriously ill patients awaiting their transplant. Thank you for helping us to make this happen Manage Cookie Preferences Do you have a spare five minutes to help us improve our website?I'll do itNo thanks