Published online Jun 26, 2020. doi: 10.12998/wjcc.v8.i12.2542
Peer-review started: February 24, 2020
First decision: March 27, 2020
Revised: April 1, 2020
Accepted: June 2, 2020
Article in press: June 2, 2020
Published online: June 26, 2020
Anthracycline chemotherapy drugs in breast cancer can increase the risk of cardiac toxicity. In order to prevent the occurrence of cardiac toxicity, early and accurate prediction of cardiac toxicity is helpful for adjusting the dosage during treatment. Current methods for detecting cardiotoxicity include echocardiographic indicators, two-dimensional ultrasound speckle tracking imaging, and serum natriuretic peptide. However, these methods have some limitations. New methods need to be developed for early detection of cardiotoxicity caused by chemotherapy.
Increased left atrial volume is an early manifestation of cardiac toxicity. Real-time three-dimensional echocardiography (RT3DE) has made it possible to measure left atrial volume precisely. This method does not rely on the geometry of the left atrium, and can dynamically observe the movement and volume changes of the left atrium. But so far, most studies have only explored the relationship between left atrial volume and left ventricular diastolic function. Few studies measure left atrial volume to predict early cardiac toxicity by RT3DE.
To evaluate the RT3DE indicators during chemotherapy to observe changes in left atrium volume in breast cancer patients undergoing chemotherapy, and to assess whether such indicators can help early predict the occurrence of cardiac toxicity.
All breast cancer patients underwent surgical treatment, and four cycles of chemotherapy (T1-T4) were routinely performed after surgery. Patients underwent two-dimensional, RT3DE, or serological examinations before and after each cycle of chemotherapy. Patients were included in either a toxic group (ΔLVEF > 10%) or a non-toxic group (ΔLVEF ≤ 10%). Repeated measurement analysis of variance was used to compare changes in conventional echocardiographic indicators, serological indicators, and RT3DE indicators before and after treatment. Multivariate logistic regression was used to find independent influencing factors on cardiac toxicity. Receiver-operating characteristics (ROC) curve analysis was performed to analyze the predictive value for cardiotoxicity caused by chemotherapy.
The present study found that T4 cTnI, T4 Pro-BNP, T3 LAVmin, T4 LAVmin, T3 LAVprep, and T4 LAVprep had significant effects on cardiac toxicity, suggesting that LAVmin and LAVprep of RT3DE could be used to earlier predict the cardiotoxicity than other indicators. ROC curve analysis results showed that T4 LAVmin had the highest AUC for diagnosing cardiotoxicity (AUC = 0.947), followed by T4LAVprep (AUC = 0.899). In addition, T4 LAVmin and LAVprep were more accurate in predicting cardiac toxicity than T3 LAVmin and T3 LAVprep. These results indicated that the RT3DE index in the third chemotherapy cycle can only early alert the occurrence of cardiac toxicity, and it needs to be tested in the fourth cycle to accurately predict cardiac toxicity.
The left atrial volume detected by RT3DE is the most accurate method for predicting cardiotoxicity caused by chemotherapy, and it is expected to be used to guide clinical adjustment of the dosage and schedule in time.
Since the follow-up time is too short to accurately determine the patients with cardiotoxicity, cardiotoxic symptoms may be delayed and omitted in some patients. A larger, multi-center study should be conducted to provide useful information for the evaluation of the cardiotoxicity caused by chemotherapy drugs in the further study.