🤖 AI Summary
Existing low-dose computed tomography (LDCT) analysis typically treats pulmonary and cardiac assessment as disjoint tasks, neglecting their physiological interdependence and shared imaging biomarkers.
Method: We propose the first interpretable cross-disease reasoning framework for integrated cardiopulmonary risk assessment from a single LDCT scan. It comprises a lung-aware module that extracts pulmonary abnormality representations, a knowledge-guided reasoning module—integrating medical knowledge graphs and clinical logic—and a cardiac representation module that generates pathophysiologically consistent cardiovascular risk predictions. Our agent-based reasoning explicitly models the “pulmonary abnormality → cardiovascular risk” pathological pathway, bridging imaging features with underlying physiological mechanisms.
Contribution/Results: Evaluated on the NLST cohort, our method significantly outperforms unidisease models and purely data-driven approaches in both cardiovascular disease screening and all-cause mortality prediction. Crucially, it produces clinically verifiable, mechanistic reasoning paths, establishing a novel paradigm for expanding the clinical utility of routine LDCT.
📝 Abstract
Low-dose chest computed tomography (LDCT) inherently captures both pulmonary and cardiac structures, offering a unique opportunity for joint assessment of lung and cardiovascular health. However, most existing approaches treat these domains as independent tasks, overlooking their physiological interplay and shared imaging biomarkers. We propose an Explainable Cross-Disease Reasoning Framework that enables interpretable cardiopulmonary risk assessment from a single LDCT scan. The framework introduces an agentic reasoning process that emulates clinical diagnostic thinking-first perceiving pulmonary findings, then reasoning through established medical knowledge, and finally deriving a cardiovascular judgment with explanatory rationale. It integrates three synergistic components: a pulmonary perception module that summarizes lung abnormalities, a knowledge-guided reasoning module that infers their cardiovascular implications, and a cardiac representation module that encodes structural biomarkers. Their outputs are fused to produce a holistic cardiovascular risk prediction that is both accurate and physiologically grounded. Experiments on the NLST cohort demonstrate that the proposed framework achieves state-of-the-art performance for CVD screening and mortality prediction, outperforming single-disease and purely image-based baselines. Beyond quantitative gains, the framework provides human-verifiable reasoning that aligns with cardiological understanding, revealing coherent links between pulmonary abnormalities and cardiac stress mechanisms. Overall, this work establishes a unified and explainable paradigm for cardiovascular analysis from LDCT, bridging the gap between image-based prediction and mechanism-based medical interpretation.