Abstract 21152: Prognostic Utility of Exercise Treadmill Test in Women Is Enhanced by Application of Non-Electrocardiographic Exercise Test Variables
Objective: The limited diagnostic accuracy of the exercise treadmill test (ETT) in women with chest pain has promoted more costly stress imaging in this population. We hypothesized that non-ECG variables of ETT could enhance the utility of ETT in women.
Methods: We evaluated ETT in women referred for chest pain from 9/96 to 10/03 who had a normal electrocardiogram and no cardiovascular disease (CVD). Longterm course (all-cause mortality) and CVD morbidity (myocardial infarction, heart failure, revascularization, stroke) was analyzed in relation to ETT results.
Results: ETT were analyzed in 1,000 women (53.5 ± 10.8 y.o., 24-85). Follow-up was 6.4 ± 2.4 yr, mortality = 2.4% (0.4%/yr), morbidity = 7.9% (1.2%/yr), mortality + morbidity = 9.8% (1.5%/yr). Diagnostic ETT (≥85% maximum predicted heart rate [MPHR]) was achieved in 96.1% (961/1000). ETT was negative (NEG) (<1.0 mm horizontal ST↓ [ST↓]) in 79.1% (791/1000); positive (POS) (≥1.0 mm ST↓) in 17.0% (170/1000); nondiagnostic (ND) (no ST↓, <85% MPHR) in 3.9% (39/1000). Morbidity was greater in ND (23.1%) than in POS (11.8%) and in NEG (6.3%) (p<0.0001). Mortality + morbidity was also greater in ND (28.2%) than in POS (14.7%) and in NEG (7.8%) (p<0.0001). Further, there was an inverse relation between Duke treadmill score (DTS) and mortality + morbidity (figure) as well as between METs achieved on ETT.
Conclusion: Thus: 1) A large majority of women achieved diagnostic ETT; 2) ETT characterized by variables indicating low functional capacity (ND, DTS, METs) were associated with increased adverse outcomes; 3) Consideration of non-ECG ETT variables can enhance the prognostic utility of ETT and reduce the need for more costly tests.
Relationship between Duke treadmill score and mortality + morbidity.
- © 2010 by American Heart Association, Inc.