Shares of the medical device maker Abiomed Inc. fell sharply after the Danvers company reported lower profit in the third quarter, despite posting strong sales growth. Abiomed reported third-quarter fiscal 2013 revenue of $38.3 million, up 19 percent, compared to $32.2 million in fiscal 2012, on record quarterly patient product usage. Abiomed also reported net income of $2.7 million, or 7 cents a share, compared to net income of $2.9 million, 7 cents, in fiscal 2012.