ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the changes in the mechanical properties of the right ventricular myocardium (RVM) after chemotherapy using three-dimensional speckle tracking echocardiography (3D-STI).</p><p><b>METHODS</b>Thirty-six breast cancer patients receiving chemotherapy with pirarubicin underwent examinations with 3D-STI to test the mechanical properties of the RVM before chemotherapy and at the end of the second, fourth, and sixth cycles of chemotherapy (C2, C4, and C6, respectively). Blood levels of hs-cTnI and NT-proBNP were also examined at the same time points. Thirty-one of these patients also underwent Tc-MIBI and F-FDG myocardial perfusion/metabolism imaging at C6. Myocardial perfusion abnormalities and survival outcomes of the patients were analyzed according to radionuclide imaging results.</p><p><b>RESULTS</b>Compared with that before chemotherapy, RVGLS at C2 was significantly lowered, and both RVGLS and RVGAS were significantly decreased at C4 and further decreased at C6 ( < 0.05) in relation with the cumulative drug dose. The RVGLS and RVGAS differed significantly among patients with different levels of TAPSE, hs-cTnI, and RV-FAC decline after chemotherapy. RVGLS and RVGAS were found to significantly correlate with FAC (=0.37, 0.26), TAPSE (=0.43, 0.51), and S' (=0.21, 0.36) ( < 0.01), and showed a high sensitivity and specificity for identifying RV-FAC decline by > 5%. Myocardial perfusion/metabolic imaging showed normal myocardial perfusion in 17 patients, and abnormal myocardial segments of the RVM were detected in 14 patients, but F-FDG imaging showed that these myocardial segments were all viable; these 14 patients showed significantly decreased RVGLS and RVGAS and significantly increased hs-cTnI level compared with the patients with normal ventricular myocardial perfusion ( < 0.05). ROC curve analysis showed that an absolute value of RVGLS less than 18.2% had a sensitivity of 92.9% for diagnosis of RV impairment with a diagnostic specificity of 88.2% and an area under the curve of 0.87. RVGAS less than 26.8% had a sensitivity of 94.8% and a specificity of 86.6% for diagnosis of RV damage with an area under the curve of 0.86.</p><p><b>CONCLUSIONS</b>3D-STI can provide a reliable new approach to early diagnosis of changes in the mechanical properties of the RVM related with chemotherapy with pirarubicin in breast cancer patients.</p>