Sales from Heartland Payment Systems Inc.'s card-processing business totaled $17.1 billion during the second quarter, which ended June 30, up 28.6% from $13.3 billion during the same period last year. The company did not report the number of transactions it processed during the quarter. The Princeton, N.J.-based payments processor attributed the growth in sales to the addition of "larger and more profitable merchants" to its processing platform. Meanwhile, interchange costs accounted for $282 million of the company's $375.5 million in total expenses for the quarter, up 15.1% from $245 million during the same period last year. Overall expenses rose 18.4% from $317.2 million a year ago. The company reported second-quarter net income of $11.5 million, up 10.6% from $10.4 million during the same period last year. Revenues rose 18.4%, to $394.6 million from $333.4 million.