Trastuzumab chemotherapy has been associated with left ventricular (LV) dysfunction. We aimed to assess early changes in LV and right ventricular (RV) mechanics associated with trastuzumab treatment for breast cancer. As well as explore whether early changes in 2-dimensional (2D)-speckle tracking echocardiography (STE) could predict later chemotherapy-induced cardiotoxicity.

Thirty-one patients with breast cancer who received Trastuzumab treatment were included. Echocardiograms were available for analysis with 2D-STE at the following time points: pretreatment (T0), 4 months (T1), and 12months (T2). All patients had a normal pretreatment LV ejection fraction (LVEF). Cardiotoxicity was defined as a decrease in LVEF of at least 10percentage points from baseline on follow-up echocardiography.

Cardiotoxicity developed in 6 of the 31 patients (19%). The mean (±SD) LVEF at T0 was 66% (±6); at T1 60% (±7); and at T2, 54% (±6). Global longitudinal strain (GLS) at T1 was the strongest indicator of subsequent cardiotoxicity (area under the curve, 0.85; cutoff value, −14.7; sensitivity, 91%; specificity, 82%; P=0.003). The average 2D LV GLS was −20.58% (±2.2) with a statistically significant decrease at T1 and T2 (LVGLS −19.35 (±2.1) and−18.55 (±2.3), P<0.001 respectively). The average 2D LV radial strain was 34.71% (±7.8) and the circumferential strain was −18.92% (±3.9). Compared with baseline (T0), LVGLS, LV circumferential strain, and right ventricular longitudinal strain at T1 and T2 were reduced significantly in patients with cardiotoxicity (P<0.05).

Trastuzumab treatment leads to early deterioration of LV GLS and circumferential strain. Right ventricular GLS and radial strain were also affected. Early changes in GLS are good predictors of subsequent development of trastuzumab-induced cardiotoxicity.