Multimodality imaging is effective in the early detection and monitoring of cardiotoxicity in cancer patients. Previous publications ^[1][29] demonstrate that the combination of echocardiography and cardiac MRI provides a more accurate assessment of left ventricular function than either modality alone. However, despite the potential benefits of multimodality imaging, there are some limitations and challenges to its use in clinical practice. These include the cost of imaging, the need for specialized training and expertise to interpret results, and the lack of standardized protocols for imaging and interpretation ^[2][28].

Echocardiography is a widely used imaging modality for the assessment of cardiac function. It is non-invasive, portable, relatively inexpensive, and does not use ionizing radiation. Echocardiography via the use of global longitudinal strain (GLS) can provide information on left ventricular ejection fraction (LVEF), regional wall motion abnormalities (RWMA), and valvular function ^[3][30]. It is particularly useful in the early detection of cardiotoxicity, when changes in LVEF can be detected before the onset of symptoms ^[4][5][6][7][1,31,32,33], with three-dimensional image acquisition preferable due to reduced intra-observer variability ^[8][9][34,35]. A change in LVEF of ≥10 percentage points or a final EF of <53% following high-dose chemotherapy with autologous stem cell transplantation was associated with a higher incidence of cardiac events ^[5][31]. A reduction in GLS of at least 15% following anthracycline treatment established a correlation between an increase in the risk of cardiac events, such as heart failure, and cardiovascular death ^[1][29]. Further, an elevated risk of later cardiotoxicity was linked to a drop in GLS of at least 2.5% within the first year after anthracycline treatment ^[2][28], and a decrease in GLS of ≥10% following treatment with immune checkpoint inhibitors was associated with an increased risk of cardiac events ^[8][34]. Global circumferential strain (GCS) is a measure of the myocardial deformation around the left ventricle in a circumferential direction during systole that can be obtained using cardiovascular imaging modalities such as echocardiography and cardiac MRI; however, preliminary studies have not proved clinical benefit ^[10][36]. Tissue doppler imaging (TDI) via echocardiography can establish early subtle changes of diastolic impairment treated with anthracyclines ^[11][37], with isovolumetric relaxation time and the evaluation standard within most accredited examinations, as well as deceleration time and E and A wave assessments ^[12][38]. Within the limitations of echocardiography are limited sensitivity and reproducibility, particularly for the detection of subtle changes in myocardial function ^[13][39], as well as a dependence on patient body habits and adequate imaging windows.

Magnetic resonance imaging (MRI) is a versatile imaging modality that can provide information on both cardiac function and structure. It can detect RWMA, changes in LVEF, and myocardial fibrosis. Myocardial fibrosis is a common finding in patients with cardiotoxicity. It is a marker of irreversible damage to the heart muscle and can be detected by late gadolinium enhancement on MRI ^[14][40], with an increased risk of subsequent heart failure in patients undergoing chemotherapy ^[15][41]. Changes in GLS on MRI are associated with an increased risk of CTRCD ^[16][42], with the extent of late gadolinium enhancement being a marker of the severity of CTRCD ^[17][22]. Previous publications have described its superiority to echocardiography in the detection of (sub)clinical CTRCD, specifically in lymphoma treated with anthracyclines ^[18][43], anthracycline use in breast cancer ^[17][22], and also its role in the diagnosis of checkpoint inhibitor therapy-induced myocarditis ^[19][44]. Myocarditic changes secondary to immune checkpoint inhibitors constitute a major diagnostic criterion ^[20][27] and are defined by the 2018 updated Lake Louise criteria ^[21][45], which describe specific features seen during T1-weighted and T2-weighted imaging acquisition. MRI is now recognized for its superior diagnostic accuracy compared to other imaging modalities, such as echocardiography and nuclear medicine imaging. However, the high cost, longer scanning time, dependence on renal function for the use of gadolinium, and lower availability of cardiac MRI in some settings limit its widespread use.

In recent years, cardiac computed tomography angiography (CCTA) has emerged as a valuable tool in the diagnosis and management of various cardiovascular diseases, including coronary artery disease and coronary anomalies ^[22][46], where a significant coronary artery stenosis is taken to be >70%. It carries a high spatial resolution, which allows for the detection of small changes in cardiac morphology and function ^[22][46]. CCTA utilizes an ECG-gated 64-slice CT scanner, with various image acquisition protocols recognized ^[23][47]. It has also been shown to be useful in the assessment of cardiomyopathy. CCTA-derived extra-cellular volume fraction followed similar dynamics when compared to LVEF and GLS measured by TTE in a breast cancer population treated with anthracyclines ^[24][48]. A major limitation is the use of ionizing radiation and contrast agents that can pose risks, particularly in patients with renal impairment ^[25][49].

Nuclear cardiac scanning is a non-invasive imaging technique that utilizes radiotracers to evaluate myocardial perfusion and function. It is an alternative imaging modality in patients who cannot undergo other imaging modalities (e.g., MRI), with multigated radionuclide angiography (MUGA) and single-photon emission computed tomography (SPECT) further acquisition methods that, via a range of radioisotopes, can assess LVEF and for perfusion defects ^[26][50]. Prior examples of its clinical use include PET imaging with fluorine-18-labeled deoxyglucose (FDG) in identifying cardiotoxicity in lymphoma patients treated with anthracyclines ^[27][51]. In this case, myocardial glucose uptake was considerably lower in those who suffered cardiotoxicity than in those who did not. The use of radiation and radiotracers within nuclear imaging can pose risks, particularly in pregnant women and patients with renal impairment, which poses some limitations to its use. If a dual-phase study is needed, this can be quite laborious and not feasible for a patient who is traveling a distance to undergo the test.