Abstract 210P
Background
Treatment with trastuzumab for HER2-positive breast cancer may lead to cardiotoxicity. Early, subclinical cardiotoxicity could be recognized by repeated measurements of myocardial strain.Strain imaging can be performed with cardiac magnetic resonance (CMR), the gold standard for cardiac function evaluation. However, the availability of CMR is limited and it is experienced as a burdensome procedure. Two-dimensional speckle tracking echocardiography ST-2DE might be a reasonable and more accepted alternative.We aimed to study the predictive value of early ST-2DE for left ventricular ejection fraction (LVEF) changes during trastuzumab for HER2-positive breast cancer.
Methods
HER2-positive breast cancer patients receiving trastuzumab, with or without anthracyclines, underwent 2DE-ST at baseline and after 3 and 6 months (m) trastuzumab. Cardiac magnetic resonance (CMR) imaging (with ST) was performed at baseline and 6m. We studied the correlation between 2DE-ST- and CMR-derived global longitudinal strain (GLS) and global radial strain (GRS) measured at the same time. We then associated baseline and 3m 2DE strain measurements with later CMR-LVEF, and with cardiotoxicity, defined as CMR-LVEF <45% and/or absolute decline >10% during trastuzumab.
Results
47 patients were included. Median baseline LVEF was 60.4%. GLS measurements based on 2DE-ST and CMR showed weak correlation (Pearson’s r=0.33; P=0.041); GRS measurements were uncorrelated (r=0.09; P=0.979). 2DE-LVEF at baseline and 3m were predictive of CMR-LVEF at 6m, but 2DE-ST strain measurements were not. In contrast, the change in 2DE-ST-GLS at 3m was predictive of the change in CMR-LVEF at 6m, while the change in 2DE-LVEF was not. Importantly, the 11 patients (28%) who developed cardiotoxicity had larger 2DE-ST-GLS change at 3m than those who did not (median 5.2% versus 1.7%; odds ratio for 1% difference change 1.81, 95% confidence interval 1.11 – 2.93; P=0.016; explained variance 0.34).
Conclusions
Correlations between 2DE-ST and CMR-derived measurements were weak. Nevertheless, ST appeared useful to improve the performance of 2DE to predict LVEF changes during 6m treatment, but much remains to be done.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Promotiefonds, Albert Schweitzer Hospital, Dordrecht, The Netherlands.
Disclosure
All authors have declared no conflicts of interest.