Exercise treadmill tests in patients with low cardiovascular risk: are we wasting our time?

INTRODUCTION The efficacy and cost-effectiveness of exercise treadmill testing for patients with low cardiovascular risk is unclear. This is due to the low incidence of coronary artery disease in this population and the potential for false-positive results leading to additional invasive and expensive investigation. AIM To investigate the value of exercise treadmill testing (ETT) as a predictor of coronary artery disease in patients with different levels of cardiovascular risk. METHODS An observational study was completed on an outpatient population from a chest pain clinic (n = 529). Cross-tabulations and binary logistic regressions were used to examine relationships between variables. RESULTS A negative ETT result was recorded for 72.5% of patients with low cardiovascular risk compared to 54.3% of those with moderate or high risk. Within the low cardiovascular risk group, patients with symptoms atypical for cardiac ischaemia were 11.1-fold more likely to have a negative ETT result. Of the patients with positive or equivocal ETT results, coronary artery disease was subsequently confirmed in only 23.1% of the low cardiovascular risk group compared to 77.2% of those with moderate or high cardiovascular risk. DISCUSSION Results show low cardiovascular risk patients are significantly more likely to return negative ETT results, particularly when associated with atypical symptoms. Similarly, positive or equivocal ETTs in this group are significantly more likely to be false positives. This suggests the ETT is not efficacious in predicting coronary artery disease in patients with low cardiovascular risk. Is it therefore appropriate to offer exercise testing to this cohort or should alternative management strategies be considered?