Boston Scientific Corp. (BSX.N: Quote, Profile, Research) posted a lower-than-expected quarterly profit on Friday as sales of its flagship drug-eluting heart stents fell by 32 percent.

The cardiovascular device maker, whose shares slipped in pre-market trade, said second-quarter profit, excluding charges, was $271 million, or 18 cents per share, compared with $412 million, or 31 cents per share, a year ago.

On that basis, the consensus estimate on Wall Street was for a profit of 19 cents per share, according to Reuters Estimates.

Net earnings were $115 million, or 8 cents per share, and included a special after-tax charge of $9 million, or less than a penny per share. That compares with a year-ago loss of $4.26 billion, or $3.21 per share, including an after-tax charge of $4.54 billion, or $3.42 per share, relating to the acquisition of Guidant.

Quarterly sales dipped to $2.07 billion, missing Reuters Estimate consensus of $2.09 billion. In the year-ago quarter, Boston Scientific recorded sales of $2.11 billion.

Sales of its drug-eluting heart stents were $437 million in the quarter, down from $647 million in the year-ago period.

Pro forma sales of cardiac rhythm management products acquired in the Guidant deal were $529 million, which included $383 million of sales of implantable cardioverter defibrillators known as ICDs. In the 2006 period, cardiac rhythm management sales were $354 million, which included $273 million of ICD sales.

Looking ahead, Boston Scientific, whose shares have been languishing for the past year near five-year lows, forecast third-quarter sales of $2.0 billion to $2.1 billion and net earnings of 3 to 8 cents per share.

At this stage, the stock is trading on revenue and ICD sales, so the good news for the company is that the revenue number is within the range of expectations, said Joanne Wuensch, an analyst with BMO Capital Markets, adding that the earnings outlook is below expectations.