MONDAY, Aug. 29, 2005 (HealthDay News) -- People taking low-dose aspirin to help their hearts benefit substantially if they continue to take it in the days before they have bypass surgery, a new Mayo Clinic study indicates.
The researchers looked at more than 1,600 people who had bypass operations at the Mayo Clinic between 2000 and 2002, and found that the in-hospital death rate for those who took aspirin in the five days before surgery was 1.7 percent, compared to 4.4 percent for those who didn't.
Some surgeons have patients stop taking aspirin before the operation for fear of excessive bleeding. But the study found no increased incidence of re-operation because of internal bleeding, said Dr. R. Scott Wright, the Mayo cardiologist who was the lead author of the report in the Aug. 30 issue of Circulation.
"We were pleased to find that the perioperative death rate was significantly lower, as well as cerebrovascular events [strokes]," Wright said. "And in those who took aspirin, there was a reduced need for postoperative blood products."
The in-hospital death rate is lowered because the aspirin does what it is supposed to do -- prevent heart attacks and other cardiac events by making blood flow more freely, he added.
"We know that many of the deaths that occur after the operation are due to ischemic heart disease," in which a coronary blood vessel is blocked, Wright said.
But although the study supports the findings of smaller studies done in other countries, the case for giving aspirin before bypass surgery is not definitively proved, he said.
"This is level 2 evidence, an observational study," Wright said. "A randomized trial is needed for definitive evidence. The data from this study would justify carrying out a randomized trial in patients getting bypass study."
"These new data from the Mayo Clinic certainly help support the case for using aspirin before surgery," said Dr. Eric Topol, chairman of the department of cardiovascular medicine at the Cleveland Clinic.
The case for using aspirin immediately after bypass surgery has been proven by a number of studies showing major benefits, Topol said, but there has been a debate about its use before surgery because "the data has been a bit mixed about bleeding hazard and graft success."
The Mayo study shows that "the bleeding hazard doesn't appear to be in any way prohibitive," Topol said.
In practice, surgeons at the Cleveland Clinic generally continue use of aspirin if the bypass patient already has been taking it, he said. But it is not yet standard procedure to start a patient on aspirin in the days before surgery, unless there are unusual features, such as a high risk of a heart attack, Topol said.
The new report is another indicator of the value of aspirin in the treatment of heart disease, Wright said.
"Patients with heart disease who are not taking aspirin should ask themselves -- and their doctors -- 'Why not?'" he added.
More information
The role of aspirin in heart disease and stroke is explained by the American Heart Association.
