Segmental Cardiac Radiation Dose Determines Magnitude of Regional Cardiac Dysfunction

Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease

David Tran¹  Liza Thomas²  Luke Stefani²  Siddharth J. Trivedi²  Karen Byth³  Eng‐Siew Koh⁴  Queenie Lo⁴  Vikneswary Batumalai⁴  Lois Holloway⁴  Geoff P. Delaney⁴  James Otton⁴  Simon Tang⁴  Michael Jameson⁴ 

[1] Department of Cardiology Liverpool Hospital Sydney NSW Australia;Department of Cardiology Westmead Hospital Sydney NSW Australia;Research and Education Network Western Sydney Local Health DistrictWestmead Hospital Sydney NSW Australia;South Western Sydney Clinical School University of New South Wales Sydney NSW Australia;

关键词: breast cancer;    cardiotoxicity;    global longitudinal strain;    LV dysfunction;    radiotherapy;    strain echocardiography;   

DOI  :  10.1161/JAHA.120.019476

来源: DOAJ

【 摘 要 】

Background Subclinical left ventricular dysfunction detected by 2‐dimensional global longitudinal strain post breast radiotherapy has been described in patients with breast cancer. We hypothesized that left ventricular dysfunction postradiotherapy may be site specific, based on differential segmental radiotherapy dose received. Methods and Results Transthoracic echocardiograms were performed at baseline, 6 weeks, and 12 months postradiotherapy on 61 chemotherapy‐naïve women with left‐sided breast cancer undergoing tangential breast radiotherapy. Radiation received within basal, mid, and apical regions for the 6 left ventricular walls was quantified from the radiotherapy treatment planning system. Anterior, anteroseptal, and anterolateral walls received the highest radiation doses, while inferolateral and inferior walls received the lowest. There was a progressive increase in the radiation dose received from basal to apical regions. At 6 weeks, the most significant percentage deterioration in strain was seen in the apical region, with greatest reductions in the anterior wall followed by the anteroseptal and anterolateral walls, with a similar pattern persisting at 12 months. There was a within‐patient dose–response association between the segment‐specific percentage deterioration in strain at 6 weeks and 12 months and the radiation dose received. Conclusions Radiotherapy for left‐sided breast cancer causes differential segmental dysfunction, with myocardial segments that receive the highest radiation dose demonstrating greatest strain impairment. Percentage deterioration in strain observed 6 weeks postradiotherapy persisted at 12 months and demonstrated a dose–response relationship with radiotherapy dose received. Radiotherapy‐induced subclinical cardiac dysfunction is of importance because it could be additive to chemotherapy‐related cardiotoxicity in patients with breast cancer. Long‐term outcomes in patients with asymptomatic strain reduction require further investigation.

【 授权许可】

Unknown