Abstract
AIMS: Left atrial strain (LAS) is a novel speckle-tracking technique used in the assessment of left atrial function. It has been shown to be a marker for adverse cardiac events (heart failure, myocardial ischemia, and atrial fibrillation). This study aimed to assess the role of LAS in assessing risk for diastolic dysfunction and myocardial ischemia in stress echocardiography (SE) before and after treadmill exercise. METHODS AND RESULTS: Patients undergoing routine Bruce protocol SE had LAS measurements (reservoir, conduit, and contractile strain) assessed before and after maximal treadmill exertion. Changes in LAS were measured and compared based on the result of the SE. Consecutive SE (n = 420) were analyzed (mean age 62 ± 5 years, 37% female). LAS was able to be estimated before and after stress in 367 patients, including 313 Normal SE, 32 Ischemic SE, and 22 Abnormal DST. All LAS measurements (reservoir, conduit, and contractile strain) increased significantly in Normal SE. The LAS measurements did not significantly change for patients with Ischemic SE and Abnormal DST. Using a receiver operator curve analysis and linear regression, apical 4-chamber reservoir LAS was found to be the best differentiator between Normal SE and abnormal tests (Ischemic SE and Abnormal DST). CONCLUSION: Change in LAS before and after treadmill exercise differentiated Normal SE and abnormal SE (Ischemic SE and Abnormal DST). It may represent a novel non-invasive assessment for diastolic stress echocardiography.