CONSHOHOCKEN, Pa. (AP) — Wireless heart-monitoring device maker CardioNet late Tuesday slashed its profit and revenue outlook for 2009.

It now expects an adjusted profit of 30 cents to 35 cents per share and $156 million to $160 million in revenue. Previously, the Conshohocken, Pa.-based company forecast a profit of 69 cents to 73 cents per share and revenue between $170 million and $175 million.

According to Thomson Reuters, analysts expected profit of 66 cents per share and $171.9 million in revenue.

CardioNet said reimbursement rates have been lower than expected, and sales volume growth has been steady but has not been as good as the company estimated.

The company said it will reduce spending, but will continue with planned investments in its sales and marketing divisions, product development, and clinical research programs. It did not estimate the size of the cost cuts.

Shares of CardioNet dived $4.32, or 26.5 percent, to $12 in premarket activity Wednesday. The stock has traded between $14.28 and $35.89 over the past year.