Dobutamine stress perfusion MRI predicts myocardial infarction and death in patients with reduced heart function, according to a study presented at the 2007 Society for Cardiac Magnetic Resonance meeting in Rome last week.
Previous stress MRI studies have shown that abnormal results in patients with relatively low heart function at rest indicate a potential risk of adverse events. The new data validate these early findings and show that physicians can actually identify which patients within this group will die of a heart attack, said senior investigator Dr. W. Gregory Hundley, an associate professor of internal medicine and cardiology at Wake Forest University in Winston-Salem, NC.
"Patients who have existing heart disease make up a significant portion of the population. With this MR procedure, we can stratify their likelihood of a heart attack and put them in more aggressive risk prevention," Hundley said. "As the population ages, this subset of patients will increase."
Hundley and colleagues performed stress-rest MRI in 240 consecutive patients between April 1997 and May 2005. These patients had a left ventricular ejection fraction equal to or less than 55% and were poor candidates for other types of cardiac stress testing. The researchers recorded the wall motion score index of patients at rest after a low-dose injection of dobutamine(Drug information on dobutamine)/atropine.
They found a significant link between an increase in the wall motion score index of some patients and their likelihood of myocardial infarction and death. The predictive value of dobutamine-stress MRI was greater when the wall motion score index was ≥1.7 but ≤2.4. The association was statistically significant (p = 0.012).
The procedure might prove useful in clinical practice, particularly for patients who cannot be imaged well with existing imaging procedures, Hundley said.
For more information from the Diagnostic Imaging archives:
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