* Q2 profit also beats estimates

* Results affected by Venezuela operations (Adds background)

July 20 (Reuters) - Abbott Laboratories reported better-than-expected quarterly sales and profit as strong sales in its medical device business more than made up for the hit from an economic turmoil in Venezuela.

Abbott, which has four core divisions - nutrition, diagnostics, medical devices and branded generic pharmaceuticals, is one of the major U.S. companies to be affected by troubled operations in Venezuela.

The Latin American nation's economy contracted by 4.5 percent in the first nine months of last year as plunging oil prices, and what critics of President Nicolas Maduro see as policy missteps, took an increasing toll.

Venezuela's official annual inflation rate was the world's highest at 141.5 percent in the nine-month period.

Abbott, which rakes in two-thirds of its revenue from outside the United States, said emerging market sales increased 1.1 percent but would have risen 4.8 percent excluding the impact of Venezuelan operations.

The company's results, however, beat Wall Street estimates, largely helped by its booming medical device business, where sales rose 6.4 percent to $1.37 billion in the second quarter.

Abbott's device unit develops products for heart, diabetes and eye patients and has been helped by launches including glucose monitor FreeStyle Libre and MitraClip, which repairs heart valves less invasively.

Abbott also has been focusing on generic pharmaceuticals in emerging markets after selling its generic drugs business catering to developed markets to Mylan NV in 2014.

Sales in this unit rose 9.5 percent, excluding an unfavorable 9.1 percent effect of foreign exchange rates.

Abbott is in the process of acquiring St. Jude Medical Inc for $25 billion. St. Jude on Wednesday reported second-quarter earnings and revenue roughly in line with Wall Street estimates.

On an adjusted basis, Abbott earned 55 cents per share in the second quarter ended June 30, above the average analyst estimate of 53 cents, according to Thomson Reuters I/B/E/S.

The company's net sales rose to $5.33 billion from $5.17 billion. Analysts on average were expecting revenue of $5.24 billion. (http://prn.to/2atEUVO) (Reporting by Amrutha Penumudi in Bengaluru; Editing by Maju Samuel)