Cambridge Heart Inc. (OTC:CAMH) won a much-needed nod from the Food & Drug Administration when the watchdog agency cleared an OEM version of its microvolt T-wave alternans cardiac monitor.

The 510(k) clearance means the Tewksbury, Mass.-based firm can move forward with a deal it struck last year with Cardiac Science Corp. (NSDQ:CSCX) to incorporate the MTWA device into Cardiac Science’s Q-Stress line of heart stress-testing equipment.

The June 2009 deal between the companies marked a significant shift for Cambridge Heart, which needed to boost slumping sales of a product it says can determine the risk of a sudden heart attack. Rather than focusing on sales to physicians and hospitals, Cambridge Heart said it would look to develop an OEM version that other manufacturers could incorporate into their own products. The shift was prompted by the company’s struggles to win reimbursement for tests using the device.

In February, Cambridge Heart filed a 510(k) application with the FDA for the OEM module. With a five-year development and distribution deal already in place with Bothell, Wash.-based Cardiac Science, the regulatory clearance means the companies can focus on getting a sales and marketing operation up to speed ahead of an expected launch later this year, according to a press release.

Cambridge Heart reported sales of $802,000 for the three months ended Dec. 31, 2009, a 20 percent decrease from the same period in 2008. Cost-cutting efforts employed by the company since the first quarter of 2009, when it laid off about 33 percent of its workforce, helped pare fourth-quarter net losses some 42 percent, from $2.9 million during the fourth quarter of 2008 to $1.7 million during the just-ended quarter.

The trend continued for the full year, as Cambridge Heart narrowed its 2009 net losses to $7.4 million on $3 million in sales, compared to $10 million in losses on $4 million in sales during 2008.