Tissue Doppler Imaging and Focal, Late-Onset Anthracycline-Induced Cardiovascular Disease in Long Term Survivors of Childhood Cancer: A Research Article.

Abstract

In anthracycline-induced cardiomyopathy, the onset of diastolic dysfunction occurs before systolic dysfunction. Although, conventional echocardiogram is the standard method to assess cardiac function post anthracycline therapy, Tissue Doppler Imaging (TDI) may detect early onset cardiac diastolic dysfunction among anthracycline-recipient survivors of childhood cancers. There are limited data on the use of TDI in assessing anthracycline-associated cardiotoxicity in children. To evaluate the role of Tissue Doppler Imaging (TDI) in assessing late-onset cardiotoxicity in survivors of paediatric cancers. This was a single site, observational, blinded study of 11 long-term survivors of childhood cancer who had been treated with anthracyclines and 22 age-matched controls. The study group and the control group underwent conventional echo and TDI; operators were blind to study group. Conventional echo measurements were obtained. TDI was used to assess systolic and diastolic parameters at the mid-interventricular septum and lateral and medial annuli of the mitral valve; these parameters included: systolic wave (S'), early diastolic wave (E'), late diastolic wave (A'), Isovolemic Contraction Time (ICT), Isovolemic Relaxation Time (IRT) and Ejection Time (ET). Myocardial Performance Index (MPI) was also calculated. Conventional echo measurements were similar in both groups. Using TDI, cases had a lower mean E' velocity (9.7 ± 1.7 cm/s vs. 11.4 ± 1.3 cm/s, p=0.004) and a lower E'/A' (1.8 ± 0.5 vs. 2.2 ± 0.4, p=0.022) at the mid-interventricular septum than controls. The mean E' septum velocity in chemotherapy-recipients who also received chest radiotherapy was 8.5±0.5 cm/s in comparison to 10.2±1.7 cm/s in those that did not receive chest radiotherapy but this not achieve statistical significance. We did not find any additional associations between TDI parameters and patients' gender, age of diagnosis, length of follow-up and dose of anthracycline. In long-term survivors of childhood cancer who received anthracyclines, diastolic dysfunction can be detected earlier by using TDI before overt systolic dysfunction. Further large-scale multicenter studies are needed.