Nearly half of all heart bypass patients stop taking statins and aspirin after surgery — a commonly prescribed drug combination that keeps blood vessels open and the heart healthy.

That’s the upshot of the a new study out of Thomas Jefferson University that analyzed the electronic medical records of 381 heart patients who had undergone coronary artery bypass surgery.

The researchers found that only 52 percent of the patients were taking both aspirin and a statin medication — drugs usually prescribed to help stave off a second heart attack.

In addition, the results showed just 75 percent were taking only aspirin, and 67 percent a cholesterol-lowering statin. The researchers also found that those patients who had opted out of the statin had a 22 percent higher rate of LDL “bad” cholesterol, putting them at risk for heart attack.

Approximately 10 years after surgery, without the help of medications like aspirin and statins, one-half of bypass vein grafts become clogged, studies show. This can be easily prevented, however, by the long-term usage of medication that both the American College of Cardiology and the American Heart Association recommend.

“Our study confirms the significant under-utilization of both aspirin and statins in patients during long-term follow up after bypass surgery,” said Dr. Michael P. Savage, a professor of cardiology at Thomas Jefferson University.

“This suggests complacency, not only among patients, but also among healthcare providers regarding the need to continue appropriate measures after successful heart surgery.”

Aspirin has been prescribed to heart patients since the 1980s, when it was first discovered that the standby painkiller could reduce the risk of death from future cardiovascular problems by 42 percent. Statins have also been found to play a vital role in reducing post-operation heart risks since the mid-1990s.