KWAN Jun

Jun KWAN

Inha University Hospital

キーワード :

Echocardiography is the cornerstone of cardiac imaging and provides a feasible and non-invasive method to assess cardiac dysfunction in cancer patients with chemotherapy. Therefore, all patients who are scheduled to receive cardiotoxic chemotherapy such as anthracycline（type I cardiotoxic）or trastuzumab（type II cardiotoxic）should undergo echocardiography at baseline as a means of screening. Patients should also undergo echocardiography during treatment in order to identify chemotherapy induced cardiac dysfunction（CICD）. Symptomatic decline in left ventricular ejection fraction（LVEF）of at least 5％to less than 55％or asymptomatic reduction in LVEF of at least 10％to below 55％can be defined as CICD. However, calculating LVEF with 2D echocardiography is inaccurate and insensitivity to detect subtle change of myocardial contractility and, therefore, has major limitation for the early detection of CICD. Therefore, there is major need for accurate and reproducible parameters, able to detect early, subclinical, LV dysfunction and, thus, able to identify patients at risk. In recent years, there has been increasing research in echocardiographic techniques to improve diagnosis of CICD. In addition to routine monitoring of LV systolic function, a new technology, myocardial strain imaging using speckle tracking echocardiography, allows detection of subclinical LV systolic dysfunction before it is manifest as a reduction in LVEF. Among 3 fundamental strains（longitudinal, circumferential and radial）, longitudinal strain appears to be the most reproducible and correlates best with clinical outcomes. A recent systematic review which described myocardial deformation parameters in 1504 patients during or after cancer chemotherapy found that changes in strain precede declines in LVEF and global longitudinal strain using speckle tracking imaging appears to the optimal modality, with a 10-15％early reduction in strain the most useful parameter for prediction of cardiotoxicity.^1）　Recently the American Society of Echocardiography（ASE）and the European Association of Cardiovascular Imaging（EACVI）published a report which incorporates strain imaging into the management of cancer patients with type I or type II cardiotoxic drugs. At baseline, echocardiography with strain imaging was recommended in both patients. During and after chemotherapy, echocardiography with strain imaging was recommended at completion of therapy and 6 months later in patients with type I cardiotoxic drugs（dose£240 mg/m²）, while in patients with type II cardiotoxic drugs, it was recommended every 3 months during therapy.^2） And a relative decline in global longitudinal strain＞15％on the f/u echocardiography is defined as indicative of subclinical CICD.
References
1.Thavendiranathan P et al. Use of myocardial strain imaging by echocardiography for the early detection of cardiotoxicity in patients during and after chemotherapy. J Am Coll Cardiol 2014; 63:2751-2768.
2.Plana JC et al. Expert consensus for multimodality imaging evaluation of adult patients during and after cancer therapy: a report from the American Society of Echocardiography and the European Association of Cardiovascular Imaging. J Am Soc Echocardiogr 2014;27:911-939.