WEDNESDAY, Jan. 19 (HealthDay News) -- Twenty percent of heart attack patients stand a good chance of suffering a second attack over the following three years, an event that is nearly as likely to be caused by a new blockage as by the original one, a new study suggests.
Researchers from Columbia University Medical Center/New York-Presbyterian Hospital also found that most new blockages responsible for second heart attacks had appeared mild during the initial cardiac workup.
A group of 697 patients with acute coronary syndrome -- an umbrella term describing chest pain due to poor blood supply to the heart -- underwent angiogram and ultrasound imaging tests to track artery blockages called lesions. The group, three-quarters of whom were men, was followed for a median of 3.4 years.
"The first thing is, those who come in with a heart attack or a threatened heart attack and get a successful angiogram . . . have very low chances of a heart attack over the next three years," said study author Dr. Gregg W. Stone, director of cardiovascular research and education at New York-Presbyterian/Columbia. "That's the good news."
"I think the whole thing was certainly illustrative," Stone added. "It gave us a lot of insights into the history of atherosclerosis we didn't have."
Lesions that caused subsequent cardiac events -- including death, heart attack or progressive angina pain -- were identified as previously treated or untreated. About 20 percent of patients suffered later cardiac events over a three-year period, according to the study.
So-called "culprit" lesions, which caused the first heart attack, were found to be responsible for 12.9 percent of later events, while "non-culprit" lesions that had previously appeared mild on angiograms caused 11.6 percent of later events.
"If you do have those hidden blockages . . . they're going to obviously intensify," Stone
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