Duke treadmill score provides better risk stratification of CAD-suspected patients

The Duke treadmill scoring (DTS) system confers better risk stratification and provides more substantial information about the different classification of risks in patients suspected of coronary artery disease (CAD) compared with conventional treadmill reading, according to a study presented at the Asian Pacific Society of Cardiology (APSC) 2019 Congress held at the SMX Convention Center in Manila, Philippines.

Overall, 143 patients (mean age, 54.9 years; 58 percent female; 37 percent had CAD history) were eligible for inclusion and underwent treadmill exercise test (TET) for CAD evaluation. Using the conventional stratification, 0.69 percent of patients were stratified as high risk while 99.3 percent were nonhigh risk. [APSC 2019, poster 25]

After applying the DTS, one patient conventionally stratified as high risk was reclassified to intermediate risk. Among nonhigh-risk patients, 6.9 percent were restratified to the high-risk category, 12.5 percent to intermediate risk and 79.7 percent to low risk.

“Patients restratified to high risk Duke score will benefit from coronary revascularization based on the current guidelines, while those reclassified to low Duke score needs reassurance, prevention or medical management,” according to the researchers.

“Patients restratified to intermediate Duke scores need intensification of treatment and further noninvasive test for further prognostication,” they added.

A previous retrospective study of a Croatian regional hospital found that high-risk DTS result had great potential in stratifying patients for immediate coronary angiography. The findings suggested that DTS is a viable tool in prioritizing patients for coronary angiography in a transitional clinical setting. [Coll Antropol 2008;32:375-380]

In the current cross-sectional, prospective, descriptive study by Morilla and colleagues, patients who underwent TET at the outpatient department of the Philippine General Hospital, Section of Cardiology, for the suspicion of CAD were included. The researchers obtained and analysed clinical and treadmill parameters. They also collected, compared and analysed the results of prognostic stratification of patients using conventional vs DTS.

“There is a need to use a validated tool such as the DTS to improve prognostication of patients undergoing treadmill,” the researchers said. “We recommend study on Duke scores and their outcomes in the future.”

TET is used to screen and prognosticate CAD, which is the leading cause of death in the Philippines, according to the researchers.

DTS is a risk stratification tool that predicts cardiovascular events among patients evaluated for chest pain using TET and classifies them into low-, intermediate- and high-risk group, with the aim of identifying high-risk patients who will benefit from coronary revascularization.

“Conventional treadmill reading refers to diagnostics result with or without risk stratification,” the researchers said. “Duke scores, in addition to the conventional result being used at a tertiary hospital, might improve management of patients.”