SCOTTSDALE, Ariz. – In a period of just 13 days, a 56-year-old Gilbert, Ariz., woman has felt the beating of three different hearts – all within her own chest: First, her own, failing heart. Then, in what is considered groundbreaking in the Valley, an artificial heart. And, on day 13, a donor heart.She is the first Valley patient to have been implanted with an artificial heart, a mechanical device that replaced her own heart – a bold, yet necessary intervention intended to keep her alive until a suitable donor heart would be available and she could be transplanted.