5.1. Echocardiography
In cardio-oncology, AI has significant potential in echocardiography, supporting image classification, reconstruction, automated segmentation and quantification, and risk prediction through integration of clinical data [
33].
Before cancer treatment: AI can play a critical role in the baseline cardiac assessment of patients prior to initiating potentially cardiotoxic therapies. Through automated analysis of echocardiographic parameters such as LVEF and GLS, AI can establish accurate and reproducible reference values. Moreover, AI algorithms can detect subtle structural or functional cardiac abnormalities that may not be readily apparent to the human eye, thereby enhancing diagnostic precision and improving the identification of patients at higher risk for future cardiotoxicity. Early identification of these risks can support more informed treatment planning and the implementation of preventive strategies [
34]. During cancer treatment: throughout therapy, AI enables continuous or periodic cardiac monitoring by automating the measurement of LVEF and GLS, ensuring timely detection of even minimal changes in cardiac function. By integrating imaging findings with other clinical and biochemical data, AI can help predict cardiovascular outcomes and flag early signs of cardiotoxicity, allowing clinicians to intervene before irreversible damage occurs. Additionally, AI-assisted point-of-care imaging can standardize acquisition quality across institutions and operators, improving consistency in serial follow-up studies [
34]. And finally, after cancer treatment, in the survivorship phase, AI continues to be valuable for long-term cardiac follow-up. Automated assessment tools can track functional recovery or progression of cardiac dysfunction over time and identify late-onset cardiotoxic effects that may emerge months or years after treatment completion. By integrating longitudinal imaging data with clinical and omic profiles, AI can help stratify survivors according to cardiovascular risk and guide personalized surveillance and prevention strategies [
34].
By training convolutional neural networks (CNNs), Zhang was able to carry out image segmentation to pinpoint cardiac chambers and derive measurements of heart structure and function for constructing disease-classification algorithms. Zhang’s method is designed to unlock data mining and knowledge extraction from the massive repository of stored echocardiograms, promising substantial clinical value by integrating relatively inexpensive quantitative indicators into everyday medical workflows and enabling causal understanding that relies on consistent, long-term patient follow-up [
35]. The study is considered foundational for applying automated interpretation to monitor patients over time, though its short analysis window and potential biases limit its strength. It also omits information on the gender distribution of participants, which could influence the findings.
After imaging registration and correct segmentation, automated measurements can be made [
36]. Guidelines from the American Society of Echocardiography and the European Association of Cardiovascular Imaging recommend averaging five consecutive cardiac cycles to calculate LVEF. In clinical practice, however, the process is often time-consuming, so a single representative beat is typically used to estimate LVEF [
37]. Therefore, the use of AI may have a definite impact on time-saving when calculating LVEF and other essential measurements. Another important challenge that AI has the potential to address is inter- and intra-observer variability, which affects all imaging modalities. For instance, studies have shown that LVEF measurements can differ between readers by as much as 10%. Notably, a 10% decline in ejection fraction is the same threshold used to define clinically significant cardiotoxicity, which may necessitate interruption of chemotherapy. This degree of variability poses a considerable challenge in cardio-oncology, as small reductions in LVEF are often attributed to measurement noise rather than true cardiac injury, potentially delaying detection of cardiotoxicity. Automation offers a solution to these issues by standardizing measurements and reducing variability [
38,
39]. Nonetheless, the role of the specialist remains indispensable for interpreting AI-generated results, applying clinical context, and ensuring the accuracy and reliability of automated assessments.
It is important to note that transthoracic echocardiography (TTE) has a more complex role than just appreciating GLS and LVEF, being an essential tool in cardio-oncology to assess ventricular, atrial, valvular, and pericardial structure and function in patients with current or past cancer [
4,
40].
In a large recent study, investigators assessed the use of AI for echocardiographic quantification. Using 877,983 measurements from 155,215 studies at Cedars-Sinai Medical Center (CSMC), they developed EchoNet-Measurements, an open-source DL model for automated annotation of 9 B-mode and 9 Doppler parameters. The model showed high agreement with sonographer measurements on internal CSMC and external Stanford Health Care (SHC) datasets (mean coverage probability 0.796–0.839; mean relative difference 0.096–0.120), with consistent performance across 2103 temporally distinct studies and various patient subgroups. These findings highlight AI’s potential to improve efficiency, accuracy, and workflow in cardiovascular imaging [
41].
Another critical potential advantage and emerging role of AI in cardio-oncology lies in its potential to identify novel markers and predictive parameters of subclinical cardiotoxicity—well before traditional measures, such as LVEF and GLS, show any detectable changes [
42,
43].
A key application of AI in cardio-oncology imaging is automated LVEF measurement using AI-assisted point-of-care echocardiography, which can streamline workflow, enhance accuracy, and enable efficient real-time cardiac monitoring during oncology visits [
33]. This approach enhances efficiency by eliminating the need for a cardiologist to be physically present at each visit, allowing reliable cardiac assessments to be performed seamlessly within oncology care settings. For example, recent studies have explored the use of AI-guided echocardiography performed by nurses with no prior ultrasound training. In one such study, each patient underwent paired limited echocardiograms—one acquired by a nurse guided by a DL algorithm and the other by an experienced sonographer without AI assistance. Five expert echocardiographers independently and blindly evaluated all studies. The results demonstrated that the DL algorithm enabled non-expert operators to obtain diagnostic-quality transthoracic echocardiograms suitable for assessing left and right ventricular size and function, as well as detecting nontrivial pericardial effusions [
44].
One notable example of how AI may increase efficacy in cardio-oncology is the FAST-EFs multicenter study involving 255 patients, which demonstrated that automated LV measurements are feasible, rapid, and highly reproducible compared with traditional visual assessment and the manual Simpson’s biplane method. The average analysis time was only 8 ± 1 s per patient, with no inter- or intra-observer variability, highlighting the efficiency and reliability of AI-assisted echocardiographic analysis [
33]. However, a limitation of the study lies in the relatively small cohort of patients.
GLS has been suggested as a more responsive indicator for the early identification of myocardial dysfunction before a measurable decline in LVEF occurs. However, some time ago, research by Farsalinos and colleagues highlighted considerable inconsistency across different echocardiography system manufacturers when assessing GLS [
45]. To address this issue, Kwan and colleagues showed that an automated deep-learning strain (DLS) workflow can help harmonize measurements across different vendors, improving inter-vendor consistency irrespective of subjective image quality [
46]. Moreover, a recent study demonstrated that, in a controlled setting, GLS measurements obtained from contemporary semi-automated clinical software are more consistent than they were a decade ago. Mid- and full-wall strain analyses were available in all but one software package. Endocardial as well as mid- and full-wall GLS measurements showed minimal inter-vendor variability, with an average maximum bias of only 0.6% strain units [
47].
In a study by Kuwahara et al., a model utilizing a dedicated software application for echocardiographic analysis was used to evaluate left ventricular function in patients undergoing chemotherapy. The primary parameter analyzed was GLS, with additional assessment of LVEF, left ventricular dimensions, mass index, left atrial volume index, and diastolic function parameters such as septal and lateral e′ velocities. The AI-assisted model achieved an intraclass correlation coefficient (ICC) of 0.81 (95% CI: 0.64–0.90) between novice and experienced clinicians, compared to 0.62 (95% CI: 0.34–0.80) with conventional methods. These results highlight the ability of AI-derived tools to provide more consistent and reliable evaluations across clinicians with varying experience levels, reducing variability in the assessment of cardiac function and enhancing reproducibility of advanced echocardiographic measurements in the cardio-oncology setting [
48].
In another study of 152 patients with HER2-positive breast cancer treated with anti-HER2 therapy and anthracyclines, AI-assisted analysis was used to obtain automated ejection fraction and GLS. These AI-derived values showed strong concordance with those obtained using standard software, with a median standard deviation of strain values of only 1.2% during serial echocardiographic monitoring, underscoring the accuracy and reliability of AI-based measurements [
49].
Moreover, recently, Salte et al. evaluated another AI method for fully automated AI-based measurement of LV GLS in echocardiography. The AI successfully identified all three standard apical views and performed cardiac event timing in 89% of patients. It also automated segmentation, motion estimation, and GLS measurement across diverse cardiac pathologies and LV function ranges. GLS measured by AI was −12.0 ± 4.1% versus −13.5 ± 5.3% by the reference method, with a bias of −1.4 ± 0.3% (95% limits of agreement: 2.3 to −5.1), comparable to intervendor variability. The fully automated analysis eliminated measurement variability and was completed within 15 s [
50]. AI-enabled, standardized GLS measurements across vendors could facilitate the detection of subtle, early signs of cancer therapy–related cardiotoxicity that may not yet produce measurable changes in LVEF.
A notable example of DL in echocardiography is EchoNet, a model trained on over 2.6 million echocardiogram images from 2850 patients. EchoNet demonstrated the ability to identify cardiac structures, assess function, and even predict systemic risk factors such as age and weight. The model accurately detected the presence of pacemaker leads (AUC = 0.89), left atrial enlargement (AUC = 0.86), and left ventricular hypertrophy (AUC = 0.75). It also provided reliable estimates of left ventricular end-systolic and diastolic volumes (R
2 = 0.74 and 0.70, respectively) and ejection fraction (R
2 = 0.50), while predicting age (R
2 = 0.46), sex (AUC = 0.88), weight (R
2 = 0.56), and height (R
2 = 0.33). Interpretability analyses confirmed that EchoNet appropriately focused on key cardiac structures during explainable diagnostic tasks and highlighted novel regions of interest when predicting complex systemic phenotypes—suggesting that such AI models may uncover new, clinically relevant imaging biomarkers beyond human perception [
42].
Another study presented EchoNet-Dynamic, a video-based AI model that analyzes full echocardiogram videos across multiple cardiac cycles. The model was trained on 10,030 annotated echocardiogram videos and demonstrated the ability to segment the left ventricle (Dice Similarity Coefficient 0.92), estimate ejection fraction (mean absolute error 4.1%), and classify heart failure with reduced ejection fraction (AUC 0.97). In an external dataset, performance remained strong, with a mean absolute error of 6.0% for ejection fraction and an AUC of 0.96 for heart failure classification. Prospective evaluation indicated variability comparable to or lower than that of human experts. By incorporating information across multiple cardiac cycles, EchoNet-Dynamic can assess subtle changes in ejection fraction with high reproducibility. The study also released the largest publicly available annotated echocardiogram video dataset to facilitate further research in AI-assisted echocardiography [
51].
Cai et al. developed MMnet, a hybrid DL and ML model designed to automate the grading of diastolic function using echocardiographic data. The model analyzes key parameters, including mitral E and A wave velocities, septal and lateral e’ velocities, tricuspid regurgitation velocity, LVEF, and left atrial end-systolic volume, extracted from 2D grey-scale, pulse-wave, and tissue Doppler images. By integrating these features, MMnet delivers accurate and efficient diastolic function grading, demonstrating the potential of AI to enhance echocardiographic diagnostics with high precision and strong clinical applicability [
52].
In a longitudinal prospective cohort study of 248 breast cancer patients receiving 240 mg/m
2 of doxorubicin, supervised machine learning algorithms were applied to identify echocardiographic strain patterns most strongly associated with subsequent cardiotoxicity. Participants underwent 2D echocardiography at baseline, 4 months, and annually thereafter, with strain and strain rate analyses performed using
TomTec Cardiac Performance Analysis software. The application of ML enabled the discovery of specific strain-based features predictive of cardiotoxicity, offering a promising approach for early detection of subclinical cardiac dysfunction in patients undergoing anthracycline therapy [
53].
Chang et al. developed an AI-based predictive model using clinical, laboratory, and echocardiographic data from patients with newly diagnosed breast cancer, preparing for anthracycline therapy (2014–2018). The model incorporated 15 variables spanning clinical characteristics, chemotherapy regimens, and echocardiographic measurements, with the most influential predictors being trastuzumab use, hypertension, and cumulative anthracycline dose. The algorithm analyzed patterns in these data to identify patients at higher risk of CTRCD and heart failure with reduced ejection fraction. The study found that the model performed well in risk stratification, highlighting its potential to support early identification and management of patients susceptible to anthracycline-induced cardiotoxicity [
54].
In a longitudinal retrospective study of 4309 cancer patients, echocardiographic data effectively predicted cardiac dysfunction, whereas laboratory data added little additional predictive value [
55]. Echocardiographic data alone achieved an AUC of 0.85, compared with 0.74 for laboratory data alone. The combined model incorporating both data types performed best, with an AUC of 0.91 for diagnosing cardiac dysfunction [
55]. The authors planned for the algorithm to be made available in an online risk stratification tool.
In a recent follow-up study, the research group applied ML to large-scale institutional electronic medical records to predict adverse cardiac outcomes in cancer survivors. They identified four clinically significant subgroups with distinct incidences of cardiac events and mortality, demonstrating that machine learning algorithms analyzing patient similarities over time can help identify survivors at increased risk of cardiac dysfunction [
56].
Another promising application involves AI-driven re-analysis of stored imaging data within Picture Archiving and Communication Systems (PACS). Advances in AI image interpretation now allow automated review of previously acquired studies, improving diagnostic consistency and accuracy while reducing inter- and intra-observer variability [
57].
Several vendors now provide AI-assisted tools for measuring LVEF. Evidence from a randomized clinical trial suggests that AI-based LVEF assessment may improve accuracy, efficiency, and reproducibility compared with conventional echocardiographic interpretation. Such tools have the potential to streamline clinical workflows, reduce inter-observer variability, and facilitate earlier detection of subclinical cardiac dysfunction [
58].
Table 1.
Key studies of AI applied to echocardiography.
Table 1.
Key studies of AI applied to echocardiography.
| Study | Task | AI Method | Cohort | Validation | Performance | Explainability | Main Contribution |
|---|
| Knackstedt et al. [33] | Automated LVEF & GLS | ML/DL | 255 patients, multicenter | Internal | ICC > 0.9, time 8 ± 1 s | No | Fast, reproducible EF/GLS |
| Zhang et al. [35] | Full echo interpretation | CNN | ~2850 patients | Internal | EF R2 ≈ 0.50, volume R2 ≈ 0.70 | Partial | Foundational automated echo |
| Sahashi et al. [41] | 18 echo parameters | DL | 155,215 studies | External | Mean rel. diff 0.096–0.120 | No | Large-scale automation |
| Salte et al. [50] | Automated GLS | DL | ~200 patients | Internal | Bias −1.4 ± 0.3%, LoA −5.1 to 2.3 | No | Eliminates variability |
| Kuwahara et al. [48] | GLS in chemo pts | DL | 243 patients | Internal | ICC 0.81 vs. 0.62 manual | No | Improves reproducibility |
| Ouyang et al. [51] | Beat-to-beat EF | DL video | 10,030 videos | External | MAE 4.1–6.0%, AUC 0.96 | Partial | Video-based EF |
| Ghorbani et al. [42] | Structure + phenotype | DL | 2.6 M images | Internal | Pacemaker AUC 0.89, LAE AUC 0.86 | Yes | Shows biological attention |
| Cai et al. [52] | Diastolic grading | DL + ML | ~1000 patients | Internal | Accuracy ~90% (reported) | No | Automated grading |
| Narang et al. [44] | AI-guided acquisition | DL | 240 patients | External | Diagnostic quality in >90% | No | Enables non-experts |
| He et al. [58] | AI vs sonographers | DL | 3769 studies | Prospective | Lower variability vs. humans | No | Workflow improvement |
| Cheng et al. [53] | Strain → CTRCD | ML | 248 patients | Internal | AUC ~0.80 | Partial | Early risk detection |
| Chang et al. [54] | CTRCD risk | ML | NA | Internal | AUC ~0.85 | Partial | Multivariable risk |
| Zhou et al. [55] | CTRCD prediction | ML | 4309 patients | Internal | AUC 0.91 (combined model) | No | Echo dominates prediction |
| Hou et al. [56] | Survivor phenotypes | ML | 4632 patients | Internal | Distinct event curves | No | Risk stratification |
5.2. Magnetic Resonance Imaging
CMR is widely recognized as the gold standard for assessing ejection fraction and providing non-invasive tissue characterization, offering critical information to guide treatment decisions, particularly in patients receiving potentially cardiotoxic cancer therapy [
59]. CMR can also give information/hints about the underlying mechanisms of cardiotoxicity.
A valuable study showed that DL-based fully automated analysis of left ventricular volumes and function is feasible, extremely fast and shows respectable performance without any manual corrections. Even with manual corrections—which are required for precise results in most patients—this approach remains time-efficient compared to manual analysis [
60].
Fully automated cardiac localization and image plane acquisition are now commercially available, significantly reducing scan and analysis time while accurately detecting artifacts and enabling corrective actions or repeat acquisitions. AI-driven methods in parallel and real-time imaging, as well as compressed sensing, support faster image capture without loss of diagnostic accuracy. Furthermore, the use of AI in CMR tissue characterization—including radiomics and texture analysis—has enhanced the assessment of scar imaging, wall thickening, and inflammation [
61].
A neural network has been developed to reconstruct cMRF T1 and T2 maps directly from undersampled spiral images in under 400 ms. The method is robust to varying cardiac rhythms, enabling rapid, real-time display of cMRF maps [
62].
Edalati et al. evaluated two AI-based DL approaches for automated slice alignment (EasyScan) and cardiac shimming (AI shim) in cardiac MRI. The models were trained and validated on datasets from over 500 subjects. In subsequent prospective studies, AI-guided slice planning reduced operator dependence and shortened scan times by approximately 2 min (∼13% faster) compared to manual planning, while improving plane accuracy. AI shim enhanced B0 magnetic field homogeneity compared with conventional volume shimming. Overall, these AI tools demonstrated more efficient, standardized, and higher-quality cardiac MRI acquisition [
63]. Despite not being built on dedicated oncologic patient populations, these studies underscore how their methodologies and insights could be meaningfully adapted to advance cardio-oncology practice.
The activity of some ICI displays cross-reactivity with cardiac proteins such as titin, which can determine myocarditis [
64]. Of note, myocardial changes associated with ICI therapy are frequently initially subclinical and asymptomatic, which makes establishing a definitive diagnosis challenging. In addition, it may be difficult to ascertain whether early cardiotoxic changes reflect new toxicity or pre-existing myocardial damage [
65]. Therefore, it is essential to use the most sensible methods in uncovering these subtle changes. CMR is most specific for tracking myocardial changes during or after myocarditis [
66]. In some studies, artificial intelligence has been employed to detect early imaging changes suggestive of subclinical myocarditis. In one such study, early gadolinium enhancement (EGE) was assessed alongside left ventricular functional parameters using AI-based algorithms applied to CMR images from patients with acute myocarditis, highlighting a significant role for EGE, according to the Lake Louise criteria, in the evaluation of patients with a clinical suspicion of acute myocarditis [
67].
Novel approaches, such as feature tracking, tagging and fast-strain-encoded CMR techniques are emerging means to assess myocardial strain using CMR [
68].
Kar et al. investigated whether AI-derived GLS from left ventricular MRI could serve as an early, independent predictor of Cancer Therapy–Related Cardiac Dysfunction (CTRCD) in breast cancer patients receiving chemotherapy. Using DENSE MRI in 32 patients at baseline and 3- and 6-month follow-ups, two DeepLabV3+ fully convolutional networks automated LV segmentation and 3D strain computation. Cox proportional hazards models incorporating clinical and contractile factors demonstrated that GLS predicted CTRCD risk independently of LVEF. This AI-guided GLS approach may enable earlier identification of at-risk patients and guide cardioprotective strategies, though the study was limited by its single-center design and lack of external validation [
69].
The StrainNet study investigated a convolutional neural network designed to perform myocardial strain analysis on cine CMR images from 161 healthy participants. The model demonstrated markedly improved accuracy in both global and segmental strain measurements compared with conventional post-processing techniques, highlighting its potential to enhance the precision and efficiency of CMR-based functional assessment [
70].
Measurements of left atrial remodeling and vascular stiffness are increasingly accessible tools for assessing long-term cardiovascular risk following cancer therapy. For instance, in two studies of patients with hematologic malignancies treated with the tyrosine kinase inhibitor ibrutinib, abnormal left atrial strain and size on echocardiography, as well as elevated native T1/T2 values on cardiac MRI, were strongly predictive of future major adverse cardiac events and other complications [
71,
72]. Using AI to automate the calculation of these parameters could greatly accelerate the process and warrants evaluation in future studies.
In radiotherapy, cardiac substructure dose metrics are more predictive of late cardiac complications than whole-heart measures. Magnetic resonance-guided radiation therapy (MRgRT) allows visualization of substructures during daily localization, offering opportunities for improved cardiac sparing. One study extended the nnU-Net deep learning framework with self-distillation (nnU-Net.wSD) for substructure segmentation in MRgRT. Across 12 substructures, the model achieved a mean Dice similarity coefficient of 0.65 ± 0.25, outperforming a standard 3D U-Net (0.583 ± 0.28;
p < 0.01), with better performance when leveraging fractionated data. Predicted contours generated dose-volume histograms closely matching clinical plans, with mean and maximum dose deviations of 0.32 ± 0.5 Gy and 1.42 ± 2.6 Gy, respectively. Volumes were largely consistent across institutions, with minor variability in coronary arteries. These results represent an important advance toward rapid and reliable cardiac substructure segmentation to enhance cardiac sparing in low-field MRgRT [
73].
Table 2.
Key studies of AI applied to cardiac magnetic resonance imaging.
Table 2.
Key studies of AI applied to cardiac magnetic resonance imaging.
| Study | Task | AI Method | Cohort | Validation | Performance | Explainability | Main Contribution |
|---|
| Böttcher et al. [60] | LV volumes & EF | DL | 50 patients | Internal | Dice ~0.94, small bias vs. manual | No | Fully automated LV |
| Hamilton et al. [62] | T1/T2 mapping | DL | Technical | Internal | Map error < 5% | No | Real-time mapping |
| Edalati et al. [63] | Planning & shimming | DL | >500 subjects | Prospective | ~13% scan time reduction | No | Faster acquisition |
| Yuan et al. [67] | Myocarditis detection | ML/DL | 21 patients | Internal | AUC ~0.90 (reported) | No | Detects EGE |
| Kar et al. [69] | GLS → CTRCD | DL | 32 patients | Internal | HR significant; GLS predictive | No | Early CTRCD signal |
| Wang et al. [70] | Myocardial strain | DL | 161 patients | Internal | Lower error vs. conventional | No | Better strain accuracy |
| Summerfield et al. [73] | MRgRT substructures | DL | 18 patients | Internal | Dice 0.65 ± 0.25 | No | Enables substructure sparing |
5.3. Computed Tomography
Cardiac CT enables promising AI applications, such as automated CAC scoring on ECG-gated non-contrast chest CT, with multiple validated methods demonstrating high accuracy [
74].
Detailed plaque characterization and quantification using CT offer valuable insights into various stages of coronary artery disease (CAD) [
75]. The same technology, combined with AI applications, may play a pivotal role in uncovering cancer-related complications, like accelerated CAD.
Staging CT scans have typically been considered inadequate for assessing CAD risk, largely because they are not cardiac-gated. However, recent work demonstrates that AI applied to non-gated CT imaging can reliably estimate CAC scores. This development suggests that CAD detection and risk stratification may be incorporated into routine oncologic imaging without the need for additional scans, radiation exposure, or cost [
76]. Shen et al. found that automated CAC derived from pre-treatment chest CT helped identify diffuse large B-cell lymphoma patients at higher risk for anthracycline-related cardiac dysfunction and MACE. However, the study was limited by a small sample size and inclusion of only Chinese patients, highlighting the need for broader validation [
77].
On the other hand, deep learning-based calcium scoring methods classify individual voxels rather than candidate lesions. Because most voxels in CT images are background rather than CAC, Wolterink et al. proposed a two-stage approach using two convolutional neural networks: the first CNN identified candidate voxels in coronary CT angiography, and the second CNN further discriminated true CAC from other candidates [
78].
An observational study of 315 non-contrast CT scans demonstrated that AI-based semi-automatic and automatic software produced Agatston, volume, and mass calcium scores, as well as the number of calcified lesions, with excellent correlation and agreement [
79].
A recent study demonstrated that a DL–based algorithm for CAC scoring after chest radiotherapy could predict future acute coronary events (ACE). The study evaluated breast cancer patients who received adjuvant radiotherapy (
n = 511) or did not (
n = 600) between 2005 and 2013. CAC Agatston scores were analyzed using the AI algorithm, and the individual mean heart dose (MHD) was calculated, with no radiotherapy scored as 0 Gy. The primary endpoint was ACE following breast surgery. CAC scores were significant predictors of ACE, suggesting that AI-based CAC assessment on simulation CT could help identify high-risk patients, though further studies are needed to confirm these findings [
80].
Interestingly, AI can generate a highly reliable and clinically useful cardiovascular disease risk profile from existing non-contrast chest CT scans in patients undergoing cancer treatment planning or follow-up. A DL model trained on 30,286 low-dose CT scans from the National Lung Cancer Trial successfully identified individuals at elevated risk of cardiovascular mortality (AUC 0.768), effectively transforming a lung cancer screening scan into a dual-purpose tool for cardiovascular risk assessment [
81]. Larger studies evaluating the accuracy of AI-driven CAC and atherosclerotic disease assessment from already available CT scans in breast cancer patients are currently underway. The findings may also be applicable to individuals with other malignancies who undergo non-gated chest CT [
7].
Coronary CTA radiomics identified invasive and radionuclide imaging markers of plaque vulnerability with good to excellent diagnostic accuracy, significantly outperforming conventional quantitative and qualitative high-risk plaque features. Coronary CTA radiomics may provide a more accurate tool to identify vulnerable plaques compared with conventional methods. Further larger population studies are warranted [
82].
Gernaat et al. evaluated a CNN algorithm for the automated assessment of CAC and thoracic aorta calcification (TAC) in breast cancer patients undergoing CT scans for radiotherapy planning. The study reported high reliability of the CNN algorithm in quantifying both CAC and TAC, highlighting the potential of AI to facilitate cardiovascular risk assessment in oncology patients using imaging acquired for non-cardiac purposes [
83].
Moreover, Gal et al. applied a DL algorithm for automatic quantification of CAC from CT scans in over 15,000 breast cancer patients scheduled for radiotherapy. The study demonstrated a strong correlation between the AI-derived CAC scores and cardiovascular risk, underscoring the potential of automated imaging analysis to enhance cardiovascular risk stratification in oncology populations [
84].
Importantly, yet another emerging application of AI in cardio-oncology imaging lies in the optimisation of the detection of masses. AI can improve the evaluation of cardiac masses across detection, characterization, and monitoring. Because assessment of these masses relies on analyzing tumor size, shape, and textural patterns, AI’s ability to recognize complex—and sometimes imperceptible—image features is especially valuable. Through deep learning–based differentiation of healthy and cancerous tissue, AI can precisely measure tumor dimensions, define morphology, and accurately delineate mass margins, further expanding its role in cardio-oncology [
85]. Additionally, algorithms can be incorporated, helping to determine the prognosis of the mass and to optimize its treatment [
86]. Finally, AI can assist in monitoring treatment response by tracking changes in tumor size, texture, and the emergence of any new lesions [
87].
Maffei et al. evaluated a radiomics-based AI classifier to assess the quality of automated segmentation of cardiac substructures for radiotherapy planning. Using 36 CT scans with 25 manually contoured substructures, radiomic features were extracted from both manual and automatic contours. A supervised-learning model was trained to distinguish correct from incorrect contours, achieving 82.6% accuracy and an AUC of 0.91. Key features showed strong correlation with standard quantitative metrics such as Dice index and Hausdorff distance. This approach demonstrates the potential for automated assessment of segmentation quality, which could support the expansion of autocontouring atlases and improve analysis of large radiotherapy datasets [
88].
Another study developed and evaluated a DL approach for automatic segmentation of cardiac chambers, large arteries, and localization of the three main coronary arteries in CT scans used for radiation therapy planning. The method employed an ensemble of CNNs with two output branches, one for segmentation and one for coronary artery localization, trained on reference annotations and virtual noncontrast cardiac scans. Performance was assessed using Dice score (DSC) and average symmetric surface distance (ASSD), with 2D slice DSC ranging from 0.76 to 0.88 and ASSD from 0.17 to 0.27 cm, and 3D DSC from 0.87 to 0.93 and ASSD from 0.07 to 0.10 cm. Coronary artery localization achieved DSC values of 0.80 to 0.91. Predicted dosimetric parameters showed strong correlation with planned doses (R
2 = 0.77–1.00 for chambers and large vessels; 0.76–0.95 for coronary arteries). The developed and evaluated method can automatically obtain accurate estimates of planned radiation dose and dosimetric parameters for the cardiac chambers, large arteries, and coronary arteries [
89].
Lassen-Schmidt et al. evaluated an iterative training approach to improve AI-based segmentation of the heart and mediastinum using 132 thoracic CT scans annotated by 13 radiologists. In three training iterations, initial manual segmentations of 5–25 CTs were used to train a nnU-Net, with subsequent iterations incorporating AI-generated pre-segmentations corrected by humans. Model performance improved consistently across iterations, achieving Dice similarity coefficients of 0.91 for the heart and 0.95 for the mediastinum. The approach reduced human annotation time by 50% for the heart and 70% for the mediastinum, and even a model trained on just five datasets achieved DCS above 0.90. This iterative workflow demonstrates an efficient method for developing accurate AI segmentation models while progressively minimizing human effort, with future work focusing on optimizing initial dataset size and pre-processing strategies [
90].
Jiad et al. implemented and evaluated an AI-based deformable image registration and organ segmentation method, termed AI dose mapping (AIDA), for estimating radiation dose to the esophagus and heart. The workflow required approximately 2 min per patient. Segmentations achieved mean Dice similarity coefficients of 0.80 ± 0.15 for the esophagus and 0.94 ± 0.05 for the heart, with Hausdorff distances at the 95th percentile of 3.9 ± 3.4 mm and 14.1 ± 8.3 mm, respectively. AIDA-derived heart doses were significantly lower than planned doses (
p = 0.04), and larger dose deviations (≥1 Gy) occurred more frequently with AIDA (
N = 26) than with manual dose accumulation (
N = 6). The study demonstrates that rapid estimation of radiation dose to thoracic tissues using AIDA is feasible, with metrics and segmentations comparable to manual approaches, supporting its potential application in radiotherapy planning [
91].
More recently, Borges et al. evaluated radiation dose distribution in auto-segmented cardiac substructures for left breast radiotherapy, emphasizing the importance of minimizing cardiac exposure as highlighted in the RTOG 1005 protocol. Anatomical structures were segmented using TotalSegmentator and Limbus AI, and the relationship between the cardiac area and other organs at risk was analyzed using log-linear regressions. The study found that dose-volume assessment protocols often overlook cardiac substructures, but automated tools can address these limitations. The authors correlated doses in the overall cardiac region with specific substructures, proposed planning limits, and suggested that statistical models could estimate doses for substructures lacking segmentation tools. Their findings also support the use of absolute dose-volume thresholds for future cause-effect evaluations [
92].
Table 3.
Key studies of AI applied to CT and radiotherapy planning.
Table 3.
Key studies of AI applied to CT and radiotherapy planning.
| Study | Task | AI Method | Cohort | Validation | Performance | Explainability | Main Contribution |
|---|
| Shen et al. [77] | CAC → CTRCD | DL | 1468 patients | Multicenter | AUC ~0.75–0.80 | No | Risk stratification |
| Gernaat et al. [83] | CAC/TAC scoring | CNN | ~2300 patients | Internal | ICC > 0.90 | No | Opportunistic screening |
| Gal et al. [84] | CAC → CV risk | CNN | 15,915 patients | External | Strong HR gradients | No | Large-scale validation |
| Kim et al. [80] | CAC → ACE | DL | ~1100 patients | Internal | CAC significant predictor | No | Post-RT risk |
| Chao et al. [81] | CV mortality | DL | 30,286 patients | External | AUC 0.768 | No | Dual-use CT |
| Kolossváry et al. [82] | Plaque vulnerability | Radiomics | 25 patients | Internal | AUC 0.84–0.90 | Partial | Radiomics > standard |
| van Velzen et al. [89] | Dose mapping | DL | 18 patients | Internal | R2 0.77–1.00 | No | Accurate dosimetry |
| Maffei et al. [88] | Segmentation QC | ML | 36 scans | Internal | AUC 0.91 | Partial | Automated QC |
| Lassen-Schmidt et al. [90] | Heart segmentation | DL | 132 scans | External | Dice 0.91–0.95 | No | Robust segmentation |
| Jiang et al. [91] | Dose accumulation | DL | 72 patients | Internal | Dice heart 0.94 | No | Fast mapping |