Addition of Myocardial Perfusion Imaging to Standard Exercise Testing for Initial Diagnosis May Not Improve Outcomes for Women with Suspected Coronary Artery Disease
DynaMed Weekly Update - Volume 6, Issue 42
Guidelines from the American Heart Association recommend standard treadmill exercise testing of symptomatic women as an initial evaluation for suspected coronary artery disease (CAD) ( Circulation 2005 Feb 8;111(5):682). Exercise testing in combination with myocardial perfusion imaging (MPI) to diagnose CAD is known to have better sensitivity and specificity than standard exercise testing (Am J Cardiol 1999 Mar 1;83(5):660). Despite the absence of data showing a difference in clinical outcomes, some clinicians prefer exercise testing with MPI as the initial test when evaluating women. The WOMEN randomized trial investigated the value of adding MPI to exercise testing for initial diagnosis in 824 symptomatic women. Women with typical or atypical angina (if aged 50-60 years) or nonanginal symptoms (if ? 60 years old) were randomized to standard exercise treadmill test alone vs. exercise treadmill test plus myocardial perfusion imaging (MPI) and were followed for 2 years. The primary endpoint was incidence of major cardiac adverse events, a composite of cardiovascular mortality and hospitalization for acute coronary syndrome or heart failure.
Results were normal for 64% of initial exercise tests in the exercise test alone group and 91% of MPI tests in the MPI group. Follow-up MPI testing was performed in 18% of the exercise alone group, while 9% of the MPI group had repeat MPI. In an analysis of 93.7% of the randomized women at 2 years, there were no significant differences in major cardiac adverse events (1.7% vs. 2.3%) or in hospitalization for chest pain (3% vs. 4%) (level 2 [mid-level] evidence ). Rates of angina-free status at 2 years were similar between the groups (60.4% vs. 64.9%, not significant) (Circulation 2011 Sep 13;124(11):1239).
For more information, see the Cardiac stress testing topic in DynaMed.