The pattern goes up to a 64” bust, but as written it isn’t all that well designed to accommodate larger sizes - the shoulders and neckline end up too wide. Also the side panel width doesn’t change (but I think that it should—a person who is bigger around also tends to have wider sides).

We did it as a KAL on the ample-knitters yahoo group and modified it in various ways to address these issues.

My bust is 56”. I knit the 44” size and made up the difference by increasing the width of the side panels. Also I modified the triangles at the bottom of one sweater panel to accommodate wider hips. (I won’t do that again if I make another Heartbeat Sweater, because it makes the bottom of the sweater into an upside-down vee shape. But it looks OK for this one).

I used #5 needles and continental knitting for the first front/back panel, but the fabric was too loose. I switched to #3 needles and combination knitting for the second front/back panel.

The sweater is loose on me - my gauge-fu for garments larger than socks or hats is weak. It has some drape so it looks OK at this size, but I ended up taking in the side panels. (The photos show the original size.)