Use of speckle strain to assess left ventricular responses to cardiotoxic chemotherapy and cardioprotection

The variability of ejection fraction (EF) poses a problem in the assessment of left ventricular (LV) function in patients receiving potentially cardiotoxic chemotherapy. We sought to use global longitudinal strain (GLS) to compare LV responses to various cardiotoxic chemotherapy regimens and to examine the response to cardioprotection with beta-blockers (BB) in patients showing subclinical myocardial damage. We studied 159 patients (49 14 year, 127 women) receiving anthracycline (group A, n 53, 46 17 year), trastuzumab (group T, n 61, 53 12 year), or trastuzumab after anthracyclines (group AT, n 45, 46 9 year). LV indices [ejection fraction (EF), mitral annular systolic velocity, and GLS] were measured at baseline and follow-up (7 7 months). Patients who decreased GLS by 11 were followed for another 6 months; initiation of BB was at the discretion of the clinician. Anthracycline dose was similar between group A and group AT (213 118 vs. 216 47 mg/m(2), P 0.85). Although EF was similar among the groups, attenuation of GLS was the greatest in group AT (group A, 0.7 2.8 shortening; T, 1.1 2.7; and AT, 2.0 2.3; P 0.003, after adjustment). Of 52 patients who decreased GLS by 11, 24 were treated with BB and 28 were not. GLS improved in BB groups (from 17.6 2.3 to 19.8 2.6, P 0.001) but not in non-BB groups (from 18.0 2.0 to 19.0 3.0, P 0.08). Effects of BB were similar with all regimens. GLS is an effective parameter for identifying systolic dysfunction (which appears worst with combined anthracycline and trastuzumab therapy) and responds to cardioprotection in patients administered beta-blockers.