Delayed Treatment May Result in Irreversible Heart Damage
Salvaged myocardium is significantly higher when time-to-reperfusion is 90 minutes or less
WEDNESDAY, Nov. 25 (HealthDay News) -- In patients with ST-segment elevation myocardial infarction (STEMI) who receive primary percutaneous coronary intervention, time to reperfusion is associated with the level of reversible and irreversible myocardial injury, including significantly reduced salvaged myocardium with increased time to reperfusion, according to a study the Dec. 1 issue of the Journal of the American College of Cardiology.
Marco Francone, M.D., of the Sapienza University of Rome, and colleagues used cardiovascular magnetic resonance to compare outcomes in 70 patients who were divided into the following four time-to-reperfusion groups: less than or equal to 90 minutes (group I), greater than 90 to 150 minutes (group II), greater than 150 to 360 minutes (group III), and more than 360 minutes (group IV).
Compared to groups II, III, and IV, the researchers found that group I had a significantly smaller mean infarct size (8 versus 11.7, 12.7, and 17.9 percent, respectively) and smaller microvascular obstruction (0.5 versus 1.5, 3.7, and 6.6 percent respectively), resulting in significantly larger salvaged myocardium (8.5 versus 3.2, 2.4, and 2.1 percent, respectively).
"Francone et al are to be congratulated for a dramatic demonstration of the critical importance of ischemic time in the management of STEMI patients," states the author of an accompanying editorial. "Ischemic time, rather than medical contact to treatment time, should be the new gold standard for STEMI care. The STEMI treatment protocols and treatment systems need to be established, which can reduce the ischemic time to the golden hour we have discussed for so many years."